Loess caves of Austria - UdC [PDF]

37

CADERNOS DO LABORATORIO XEOLÓXICO DE LAXE

ISIDRO PARGA PONDAL

37

ISSN: 0213-4497 Depósito Legal: C 1054-1984 Imprime: Tórculo Artes Gráficas S.A. Portada: Microgours de pigotita(Isla de Ons, Pontevedra, España (Foto C.E. Aradelas) Maquetación y supervisón del inglés: Ana Martelli Editor científico: Juan Ramón Vidal Romaní

Esta publicación se ha realizado con papel procedente de una fuente gestionada responsablemente

CAD. LAB. XEOL. LAXE 37 (2013)

ISSN: 0213-4497

ÍNDICE Pág. 1. GEOLOGICAL SKETCH AND THE NONKARSTIC CAVES OF THE BAKONY MOUNTAINS IN HUNGARY Eszterhás, I. and Szentes, G.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

11

2. FIRST DATA ON TESTATE AMOEBAE IN SPELEOTHEMS OF CAVES IN IGNEOUS ROCKS González López, L., Vidal-Romaní J. R , López Galindo, M .J., Vaqueiro Rodríguez, M. and Sanjurjo Sánchez, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

37

3. DEVELOPMENT TRENDS OF TAFONI FORMS (INCIPIENT STAGES) de Uña Álvarez, E.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

57

4. LOESS CAVES OF AUSTRIA – A PREVIEW Pavuza, R. and Plan, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

65

5. TL ESTIMATION OF AGES OF POTTERY FRAGMENTS RECOVERED FROM GRANITE CAVES IN THE NW COAST OF SPAIN Sanjurjo-Sánchez, J., Vidal Romaní, J. R., Vaqueiro Rodríguez, M., Costas Vázquez, R. and Grandal D’Anglade, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

73

6. GEOMORPHOLOGICAL MAPPING OF GRANITE CAVES Costas Vázquez, R., Suárez Pérez, R. M. and Vaqueiro Rodríguez, M. . . . .

89

7. NEW DATA ON THE LITHOSTRATIGRAPHY OF BEIRAS GROUP (SCHIST GREYWACKE COMPLEX) IN THE REGION OF GÓIS-ARGANIL-PAMPILHOSA DA SERRA (CENTRAL PORTUGAL) Meireles, C., Sequeira, A. J. D., Castro, P. and Ferreira, N. . . . . . . . . . . . . . .

105

CAD. LAB. XEOL. LAXE 37 (2013)

8. ASSESSING THE SOIL PHYSICAL CHARACTERISTICS OF THE GALLERY WOODS AREA AT THE HYDROGRAPHIC MARIANA SUBCATCHMENT FOR ENVIRONMENTAL CONSERVATION Camargo, M. F., Roque, C. G., Umetsu, R. K., Cardoso, T. R., Montanari, R. and Paz González, A.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

125

9. GROWTH AND PRODUCTIVITY OF PURGING NUT (JATROPHA CURCAS L.) CROP GROWN ON AN OXISOL IN TANGARÁ DA SERRA (MT, BRASIL) Dalchiavon, F. C., Dallacort, R., Colleti, A. J., Montanari, R. and Paz-Ferreiro, J.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

139

10. The Valborraz tungsten mine: Description of a potential source of arsenic pollution Cárdenes, V., Paradelo, R., Rubio, A. and Monterroso, C.. . . . . . . . . . . . . . .

147

11. CATASTROPHES VERSUS EVENTS IN THE GEOLOGIC PAST: HOW DOES THE SCALE MATTER? Gutak, J. M. and Ruban, D. A... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

163

12.CONTRIBUTION TO THE STUDY OF FE-TI MINERALIZATION FROM S. TORPES BEACH (SINES, SETÚBAL, PORTUGAL) Moura, A. and Pinto, F... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

181

Director de la publicación

J.R. VIDAL ROMANÍ Comité Científico A. Marcos (Oviedo); L.G. Corretgé (Oviedo); R. Vegas (Madrid); J. R. Martínez Catalán (Salamanca); F. Noronha (Porto); H. Chaminé (Aveiro); H. Granja (Braga); G. Sores de Carvalho (Braga); A. Varela (Cervo); R. Rodríguez (Madrid); R. Arenas (Madrid); C. R. Twidale (Adelaide); J. R. Vidal Romaní (A Coruña); Díaz Fierros, F. (Santiago) Editores

Seminario de Estudos Galegos. Área de Xeoloxía e Minería. Universidade da Coruña. Instituto Universitario de Xeoloxía. Objetivos de la revista Revista dedicada a la geología de Galicia en general y a la del Hercínico en particular. En consecuencia no está restringida a ningún tema de geología, o relacionado, en tanto que se refiera a temas gallegos, si bien recoge todos los que se refieren al hercínico peninsular ibérico. Se considerarán casos especiales cuando a juicio del Comité Científico de la revista sea conveniente. Periodicidad Anual con números extraordinarios dedicados a temas monográficos intercalados. Suscripción El precio es variable para cada volumen en función del número de trabajos incluidos en cada uno de ellos. Para suscripciones dirigirse a la Secretaría del Instituto Universitario de Xeoloxía, Edificio Servicios Centrales de Investigación, Campus de Elviña s/n 15071 Coruña, Spain. Teléfono (+34) 981 167000, extensión 2910. Información general Los trabajos se presentarán en CD o por correo electrónico con el texto preparado en Word 2000 o versiones más modernas para Apple Macintosh o PC. Los dibujos, gráficos o fotografías en blanco y negro deben ser adjuntadas por separado e indicar en el ejemplar mecanografiado en qué lugar del texto recomienda su inserción. Aquellas personas que no puedan enviar el texto en soporte informático, deberán hacerse cargo de los gastos que suponga para la revista realizar ese trabajo.

El trabajo deberá El trabajo incluirdeberá TÍTULO: incluir Español TÍTULO: e Inglés Español en minúsculas, e Inglés en palabras minúsculas, clave palabras en Inglés clave en Inglés y Abstract eny Inglés. Abstract en Inglés. Las citas bibliográficas Las citas bibliográficas dentro del texto dentro se pondrán del textoen se mayúscula pondrán enymayúscula la abreviatura y lapara abreviatura los para los siguientes autores siguientes será:autores "et al.".será: "et al.". Los textos enviados Los textos serán enviados sometidos serána la sometidos crítica dea los la crítica Censores de los Científicos Censoresdesignados Científicospor designados por la Revista. la Revista. Bibliografía:Bibliografía: Autores en mayúsculas Autores en ymayúsculas las revistasyolas textos revistas citados o textos en cursiva. citados en cursiva. Los autores de Loslosautores trabajos de deberán los trabajos incluir deberán su dirección incluir su completa, dirección incluido completa, código incluido postal. código postal. Separatas

Separatas

Se enviará a Se cada enviará autor auncada PDFautor con un el artículo PDF conenellaartículo versiónen final. la versión final. Envío de manuscritos Envío de manuscritos - Los trabajos- Los originales trabajos seoriginales enviarán a:se enviarán a: Instituto Universitario Instituto Universitario de Xeoloxia de Xeoloxia Edificio Servicios Edificio Centrales Servicios de Centrales Investigación de Investigación Campus de Elviña Campus s/nde Elviña s/n Telephone: (+34) Telephone: 981 167000 (+34) Ext. 981 167000 2910 Ext. 2910 Fax: (+34) 981 Fax: 167172 (+34) 981 167172 [email protected] [email protected] 15071 A Coruña 15071 (Spain) A Coruña (Spain) Incluyendo dirección Incluyendo habitual dirección y teléfono. habitual y teléfono. — Una vez — terminada Una vezlaterminada impresión,lalos impresión, originaleslosserán originales devueltos serán a su devueltos autor/es,a si su así autor/es, lo si así lo desean y expresan. desean y expresan. — El número —máximo El número de hojas máximo quedesehojas admitirá que por se admitirá trabajo será por trabajo quince será (15) incluyendo quince (15) incluyendo figuras, fotografías, figuras,mapas, fotografías, etc.. Para mapas, trabajos etc.. Para de mayor trabajos extensión de mayor se extensión ruega consultar se ruega al ediconsultar al editor científico.tor científico. — El Instituto —Universitario El Instituto Universitario de Geología de se reserva Geología el se derecho reservadeeldevolver derecho al deautor/es devolveraqueal autor/es aquellos que no sellos ajustan que no a estas se ajustan normas. a estas normas.

Director of the Director publication of the publication

J.R. VIDAL J.R. ROMANÍ VIDAL ROMANÍ Scientific committee Scientific committee

A. Marcos (Oviedo); A. MarcosL.G. (Oviedo); Corretgé L.G. (Oviedo); CorretgéR.(Oviedo); Vegas (Madrid); R. VegasJ. (Madrid); R. Martínez J. R. Catalán Martínez Catalán (Salamanca);(Salamanca); F. Noronha (Porto); F. Noronha H. Chaminé (Porto); H. (Aveiro); Chaminé H. (Aveiro); Granja (Braga); H. Granja G. (Braga); Sores de G. Sores de Carvalho (Braga); Carvalho A. Varela (Braga); (Cervo); A. Varela R. Rodríguez (Cervo); R.(Madrid); RodríguezR.(Madrid); Arenas (Madrid); R. ArenasC.(Madrid); R. C. R. Twidale (Adelaide); Twidale J.(Adelaide); R. Vidal Romaní J. R. Vidal (A Coruña); Romaní (A Díaz Coruña); Fierros,Díaz F. (Santiago) Fierros, F. (Santiago) Editors

Editors

Seminario deSeminario Estudos Galegos. de Estudos Área Galegos. de Xeoloxía Área dee Minería. Xeoloxía Universidade e Minería. Universidade da Coruña. da Coruña. Instituto Universitario Instituto Universitario de Xeoloxía.de Xeoloxía. Objectives of Objectives the journalof the journal

Journal devoted Journal to the devoted geology to the of Galician geology in of general Galicianand in general to the Hercynian and to theinHercynian particular.in particular. Therefore, it Therefore, is not restricted it is not to any restricted subject toof any geology, subjector ofrelated geology, subject, or related if it is subject, referred if ittois referred to Galician subjects, Galician though subjects, it includes though allitreferred includestoallthe referred Iberiantopeninsular the IberianHercynian. peninsularSpecial Hercynian. Special cases will becases takenwill intobeaccount taken into when account the Scientific when theCommittee Scientific of Committee the journal of considers the journal considers them convenient. them convenient. Periodicity Periodicity

Annual with Annual extraordinary with extraordinary issues devoted issues to intercalated devoted to monographic intercalated monographic subjects. subjects. Subscription Subscription

The price varies The for price each varies volume for each according volumeto according the number to of thepapers number included of papers therein. included For therein. For subscription subscription contact the Secretariat contact the of Secretariat the Instituto of the Universitario Instituto Universitario de Xeoloxia,deEdificio Xeoloxia, Edificio Servicios Centrales ServiciosdeCentrales Investigación, de Investigación, Campus de Campus Elviña s/n de 15071 Elviña Coruña, s/n 15071 Spain. Coruña, Spain. Telephone (+34) Telephone 981 167000, (+34) 981 extension 167000, 2910. extension 2910. General information General information

Papers will be Papers submitted will be in submitted CD or by e-mail in CD or with bythe e-mail text with in Word the text 2000inorWord later2000 versions or later for versions for Apple Macintosh AppleorMacintosh PC. or PC. The drawings, The graphics drawings, or photographs graphics or photographs in white and in black white must andbe black attached mustseparately, be attachedand separately, and indicate in the indicate typescript in the original typescript where original you recommend where you the recommend insertion the thereof. insertion thereof. Those persons Those whopersons cannot send who the cannot textsend in computing the text insupport computing will support have to pay will the havecharges to pay the charges for this conversion. for this conversion.

The paper will Thehave paperto will include haveTITLE: to include Spanish TITLE: and Spanish English and in lowercase, English inkey lowercase, words inkey words in English and Abstract English and in English. Abstract in English. The bibliography The bibliography quotations within quotations the text within will the be in text uppercase will be in foruppercase the first author for theand firstthe author and the abbreviation abbreviation for the othersfor will thebeothers "et al.". will be "et al.". The sent texts Thewill sentundergo texts will the undergo consideration the consideration of the Scientific of theCensors Scientific appointed Censorsbyappointed the by the Journal. Journal. Bibliography:Bibliography: Authors in uppercase Authors in and uppercase cited journals and cited or texts journals in italics. or texts in italics. The authors of Thetheauthors paper of must theinclude paper must theirinclude complete their address, complete including address, postal including code. postal code. Offprint

Offprint

Each author Each will receive author awill PDF receive with the a PDF finalwith version the final of theversion papers.of the papers. Remittance ofRemittance papers of papers

- The original- The papers original will be papers sent to: will be sent to: Instituto Universitario Instituto Universitario de Xeoloxia de Xeoloxia Edificio Servicios Edificio Centrales Servicios de Centrales Investigación de Investigación Campus de Elviña Campus s/nde Elviña s/n Telephone: (+34) Telephone: 981 167000 (+34) Ext. 981 167000 2910 Ext. 2910 Fax: (+34) 981 Fax: 167172 (+34) 981 167172 [email protected] [email protected] 15071 A Coruña 15071 (Spain) A Coruña (Spain) indicating habitual indicating address habitual and telephone. address and telephone. — Once the printing — Onceof thethe printing originals of the is finished, originalsthe is finished, originals the willoriginals be returned willtobeitsreturned author/s, to its author/s, if they wish and if they indicate wish and so. indicate so. — The maximum — The number maximum of the number pages of to the be admitted pages to will be admitted be 15 (fifteen) will be including 15 (fifteen) figures, including figures, photographs,photographs, maps, etc.. For maps, the papers etc.. Forofthe longer papers extension, of longer please extension, consultplease the scientific consult the edi-scientific editor. tor. — The Instituto — The Universitario Instituto Universitario de Xeoloxia de reserves Xeoloxia its right reserves to return its right those to papers return those whichpapers are which are not adjusted not to these adjusted rules. to these rules.

Director da publicación Director da publicación

J.R. VIDAL J.R. ROMANÍ VIDAL ROMANÍ Comité Científico Comité Científico A. Marcos (Oviedo); A. MarcosL.G. (Oviedo); Corretgé L.G. (Oviedo); CorretgéR.(Oviedo); Vegas (Madrid); R. VegasJ. (Madrid); R. Martínez J. R. Catalán Martínez Catalán (Salamanca);(Salamanca); F. Noronha (Porto); F. Noronha H. Chaminé (Porto); H. (Aveiro); Chaminé H. (Aveiro); Granja (Braga); H. Granja G. (Braga); Sores de G. Sores de Carvalho (Braga); Carvalho A. Varela (Braga); (Cervo); A. Varela R. Rodríguez (Cervo); R.(Madrid); RodríguezR.(Madrid); Arenas (Madrid); R. ArenasC.(Madrid); R. C. R. Twidale (Adelaide); Twidale J.(Adelaide); R. Vidal Romaní J. R. Vidal (A Coruña); Romaní (A Díaz Coruña); Fierros,Díaz F. (Santiago) Fierros, F. (Santiago) Editores

Editores

Seminario deSeminario Estudos Galegos. de Estudos Área Galegos. de Xeoloxía Área dee Minería. Xeoloxía Universidade e Minería. Universidade da Coruña. da Coruña. Instituto Universitario Instituto Universitario de Xeoloxía.de Xeoloxía. Objectivos daObjectivos revista da revista Revista dedicada Revista á xeoloxía dedicada deáGalicia xeoloxía ende xeral Galicia e á do enHercínico xeral e á do enHercínico particular.en Enparticular. consecuenEn consecuencia, non está cia, restrinxida non estáa restrinxida ningún tema a ningún de xeoloxía, tema de ou xeoloxía, relacionado, ou relacionado, en tanto que en se tanto refira que a se refira a temas galegos, temas si ben galegos, recollesitodos ben recolle os que todos se refiren os que ao se hercínico refiren peninsular ao hercínico ibérico. peninsular Se consiibérico. Se considerarán casosderarán especiais casos cando especiais a xuizocando do Comité a xuizoCientífico do Comité daCientífico revista sexa da conveniente. revista sexa conveniente. Periodicidade Periodicidade Anual con números Anual con extraordinarios números extraordinarios dedicados a temas dedicados monográficos a temas monográficos intercalados.intercalados. Suscrición

Suscrición

O prezo é variable O prezopara é variable cada volume para cada en función volumedo ennúmero funciónde dotraballos número incluídos de traballos en incluídos cada en cada un deles. Para un suscriciones deles. Para suscriciones dirixirse á Secretaría dirixirse ádoSecretaría Instituto do Universitario Instituto Universitario de Xeoloxía,de Xeoloxía, Edificio Servicios Edificio Centrales Servicios de Centrales Investigación, de Investigación, Campus de Elviña Campus s/nde15071 Elviña Coruña, s/n 15071 Spain. Coruña, Spain. Teléfono (+34) Teléfono 981 167000, (+34) 981 extensión 167000, 2910. extensión 2910. Información Información xeral xeral Os traballos Os presentaránse traballos presentaránse en CD ou por en correo CD ouelectrónico por correo co electrónico texto preparado co textoenpreparado Word en Word 2000 o versións 2000máis o versións modernas máis para modernas Apple Maxintosh para AppleoMaxintosh PC. o PC. Os debuxos, Os gráficos debuxos, ou fotografías gráficos ouenfotografías blanco e negro en blanco debene negro adxuntarse debenpor adxuntarse separadopor e indiseparado e indicar no exemplar car no mecanografiado exemplar mecanografiado en que lugar en doque texto lugar se recomenda do texto searecomenda súa inserción. a súa inserción. Aquelas persoas Aquelas que non persoas podan queenviar non podan o textoenviar en soporte o textoinformático, en soporte informático, deberán facerse deberán cargofacerse cargo dos gastos que dossupoña gastos para que supoña a revistapara realizar a revista ese traballo. realizar ese traballo. O traballo deberá O traballo incluirdeberá TÍTULO: incluir Español TÍTULO: e Inglés Español en minúsculas, e Inglés en palabras minúsculas, chave palabras en Inglés chave en Inglés e Abstract ene Inglés. Abstract en Inglés.

As citas bibliográficas dentro do texto poránse en maxúscula e a abreviatura para os seguintes autores será: "et al.". Os textos enviados serán sometidos á crítica dos Censores Científicos designados pola Revista. Bibliografía: Autores en maxúsculas e as revistas ou textos citados en cursiva. Os autores dos traballos deberán incluir a súa dirección completa, incluído código postal. Separatas Enviaráse a cada autor un PDF co artículo na versión final. Envío de manuscritos - Os traballos originais enviaránse a: Instituto Universitario de Xeoloxía Edificio Servicios Centrales de Investigación Campus de Elviña s/n Telephone: (+34) 981 167000 Ext. 2910 Fax: (+34) 981 167172 [email protected] 15071 A Coruña (Spain) incluindo dirección habitual e teléfono. — Unha vez terminada a impresión, os originais serán devoltos ao seu autor/es, si así o desexan e expresan. — O número máximo de follas que se admitirá por traballo será quince (15) incluindo figuras, fotografías, mapas, etc.. Para traballos de maior extensión rógase consultar ao editor científico. — O Instituto Universitario de Xeoloxía resérvase o dereito de devolver ao autor/es aqueles traballos que non se axusten a estas normas.

Cadernos Lab. Xeolóxico de Laxe Coruña. 2013. Vol. 37, pp. 11 - 36

ISSN: 0213-4497

Geological sketch and the non-karstic caves of the Bakony Mountains in Hungary

ESZTERHÁS, I.1 and SZENTES, G.2

(1) Köztársaság út 157, H-8045 Isztimér, Hungary, [email protected] (2) Alte Frankfurter Str. 22 b, D-61118 Bad Vilbel, Germany, [email protected]

Abstract The about 4000 km2 Bakony Mountains form the most extensive region of the Trans-Danubien Mountains between Lake Balaton and Marcal River. They have a typical medium relief, including plateaux of various heights, and denudated fault blocks interspersed with inter mountain basins. In the southern and western areas of the mountains, basalt cones and basaltic sheets are frequently found. In the central area, the variously sloping landscape is inclined towards the blocks. Limestone and dolomite predominate, and there are extensive karst regions and numerous karst caves. Of course, from the point of view of the non-karstic caves, these regions are insignificant. Significantly smaller is the occurrence of quartziferous (sandstone and conglomerate) and basalt rocks, however 147 non-karstic cave are known in these rocks and, in addition, 35 artificial cavities, considered as caves, are listed. The authors describe the geology, the geomorphology and the non-karstic cave development of the Bakony Mountains. Furthermore, typical examples of the caves have been selected and presented according to the different rock formations and development types. Key words: sandstone; geyserites; gas bubble; explosion cave; geyserite cave; tectonic cave; atectonic cave; break down cavity; consequence cave; talus cave; cavity between basalt columns; alkaline solution cave; ice cave; flooded cave.Abstract

12 Eszterhás and Szentes

INTRODUCTION The Bakony Mountains form a section of the 4000 km2 of the Trans-Danubien Mountains between Lake Balaton and Marcal River. They have a typical medium relief, including plateaux of various heights, and denudated fault blocks interspersed with intermontane basins. In the southern and western areas of the mountains, basalt cones and basaltic sheets are frequently found. In the central area, the variously sloping landscape is inclined towards the blocks. Limestone and dolomite predominate, and there are extensive karst regions and numerous karst caves. Of course, from the point of view of the non-karstic caves, these regions are insignificant.

CAD. LAB. XEOL. LAXE 37 (2013)

As a result of systematic research by the Volcanspeleological Collective, 147 natural non-karst caves and 35 artificial cavities have been listed in the Bakony Mountains. Fifty-six non-karstic caves have developed in basalt. Forty-one caves are listed in the geyserite of the Tihanyi Peninsula. Thirtytwo non-karstic caves appear in the Miocene calcareous conglomerate and 10 caves are known in the Pannonian quartziferous sandstone. Furthermore, 7 caves have developed in basaltic tuff and one in loess. Artificial cavities have generally been dug in basalt tuff and loess (Fig. 1). The present study intends to summarize the development of the non-karstic caves and to demonstrate their speleological significance.

CAD. LAB. XEOL. LAXE 37 (2013)

Geological sketch and the non-karstic caves 13

Fig. 1. Location of the non-karstic caves or the clusters of non-karstic caves in the Bakony Mountains

SKETCH OF THE GEOMORPHOLOGY The Bakony Mountains make up the most extensive region of the TransDanubien Mountains (3974 km2) which extends from the Zala River Valley to the Móri Trench and from Lake Balaton to the Little Hungarian Plain. The mountains are divided into three main areas along NE–SW trending fault lines, the Northern Bakony Mountains, the Southern Bakony

Mountains and the Balaton Upland. Other less significant areas of the mountains are the Keszthelyi Mountains, the Tapolca Basin and the Bakony Foreland (Fig. 1). The Northern and Southern Bakony Mountains are divided by the Veszprém- Devecser Trench, while the Veszrém – Ngyvázsony Trench separates the Southern Bakony Mountains and the Balaton Upland. The Tertiary and Quaternary uplifts formed the present elevation of the region. Young

14 Eszterhás and Szentes

tectonic movements uplifted the land more and more towards the north. The highest point of the mountains is Mount Kőris 701 m above the sea level, which rises in the north of the region. The main constituents of this region are the karstic limestones and dolomites. Many characteristic surface and subsurface karstic forms are to be found in the covered and in the opened karst regions (JUHÁSZ, 1987). The Northern Bakony Mountains make up the the highest and most extensive area in the region. The land itself is a forest covered karst, which is dotted with many romantic valleys. The creeks eroded the covering gravel sheet and have cut deep canyons into the underlying limestone or dolomite. The largest basin is the loess covered Zirci Basin, which is surrounded with the large blocks of the Northern Bakony Mountains. Surface water occurrence is insignificant, therefore, settlements are to be found only near the karst springs. The easternmost parts of the mountains are the Tési Plateau and the Bodajki Block. This is a karst region with creeks and dry valleys, with barren rock surface and patches of forest with sinkholes and caves. Southern Bakony is surrounded by the towns of Veszprém – Devecser - Sümeg and Tapolca. The eastern part, the Veszprémi Plateau, is a barren dolomite plateau from 250 to 300 m above sea level. In the western part limestone is dominant and contains many diverse karstic features. South of the Séd Valley a layer of gravel covers a basalt plateau. The 601 m high Mount Kab and Mount Agár are the most extensive stratovolcanoes in the region. The basalt is underlain by limestone and pseudokarstic depressions which appear on the basalt surface due to karstic corrosion of the

CAD. LAB. XEOL. LAXE 37 (2013)

buried limestone layers. Fertile basins are also to be found in the western area. An unusual surface formation, an altiplanation surface, is the “Stone Sea” in the Kali Basin, whilst Castle Hill at Sümeg, a western block of the Southern Bakony, is composed of Cretaceous limeston. The Keszthelyi Mountains, the westernmost part of the Bakony Mountains, are adjacent to the Balaton Uplands. The mountains consist of limestone and dolomite blocks, which are bordered on either side by steep multiple faults. Between the blocks several small basins are to be found. In the north-western part of the basalt formation the Mount Tátika Group occurs. The volcanic series of the Balaton Upland is an intra-plate monogenetic volcanic formation. The volcanic landforms are composed of denudated maars, tuff rings, spatter cones, lava lakes, valleyfilling lava flows and lava fields. The basalt has broken through and covered the loose Pannonian sediments of the Tapolca Basin. The overlying hard basalt trap has prevented denudation and thus has developed witness buttes. In some witness buttes, for instant on Mount Szent György, spectacular columnar basalt forms occur. Volcanic activity has played an important role in the formation of the Tihanyi Peninsula. The Inner Lake and the Outer Lake are the apparent remains of two calderas (BUCKÓ, 1970). Several hundred geyser cones have developed as a result of postvolcanic activity (CHOLNOKY, 1931). The base formation of the peninsula is the yellowish white Pannonian sand and clay, which crops out in the steep banks of the Lake Balaton. In the postvolcanic period erosion has significantly denuded the volcanic forms themselves and revealed the fossil surface beneath the

CAD. LAB. XEOL. LAXE 37 (2013)

Pannonian sediments. Recent valley patterns and alluvial fans have developed over the complete Bakony Mountain range. GEOLOGICAL SETTINGS The Bakony Mountains are basically composed of sedimentary rocks, which have been superimposed by young basaltic formation and geyserite in the Tihanyi Peninsula (GYALOG, 2005). The oldest formation is the Ordovician and Silurian series of phyllite and clay schist near the village of Alsóörs in the Balaton Upland. Permian red sandstone and conglomerate overlie the folded Palaeozoic bedrock with angular unconformity. Large Permian outcrops are to be found in the eastern part of the Bakony Mountains and in the Balaton Upland. The thickness of the formation is some 800 m (JUHÁSZ, 1987). The Triassic sequences have typical classical stratigraphy. The Lower Triassic strata are composed of clay shale and marl layers interspersed with thin laminated limestone and dolomite. This formation can be observed in the Southern Bakony Mountains and in the Balaton Upland. In the Middle Triassic, thick bedded dolomite has been deposited, associated to a lesser extent with limestone. This dolomite forms the Veszprémi Dolomite Plateau. Near the town of Balatonfüred, light coloured drab, bedded, nodular Füredi Limestone is characteristic, which reflects a basin facies development. The Upper Triassic thick bedded limestone and dolomite are to be found throughout the Bakony Mountains. The most prevalent and thickest rock is a carbonate platform formation, the thick bedded, light grey Great Dolomite or

Geological sketch and the non-karstic caves 15

Hauptdolomite. In the Northern Bakony Mountains, the Dachstein Limestone appears in a narrow belt. The Lower- the Middle- and the Upper Jurassic formations are to be found throughout over in the Bakony Mountains. Limestone and marl series are typical of the Lower Jurassic among others on the Tési Plateau. Also associated with the Lower Jurassic period it is the black shale-related manganese ore deposit near the village of Úrkut. The red ammonitic limestone is a typical Middle Jurassic formation in the central region of the mountains. Limestone series also occur in the Upper Jurassic. Cherty limestone was deposited in the Lower Cretaceous period in the Zirci Basin. Limestone was deposited in the Middle Cretaceous period. In the Upper Cretaceous marl, claey marl and coal seams formed near the settlements of Ajka and Csehbánya. A unique formation, which is economically important, is the Lower Cretaceous bauxite, which occurs extensively in the central region of the mountains. In the Eocene, terrestrial red clay is overlain by coal measures in the Northern Bakony Mountains, which are, in turn, overlain either by Eocene Nummulites Limestone or by algal carbonate platform sediments. The Nummulites Limestone often overlays the bauxite deposits (GYALOG, 2005). Allothigene bauxite accompanied by marl and claey marl has deposited in the Oligocene. The Miocene sedimentary sequence is either basin fill in the intermontane basins or occurs in the rims of the basins. Coarse sand and conglomerate together with calcareous sandstone form the Lower Miocene in the Eastern Bakony Mountains, which is overlain by claey, sandy coal seams in the Várpalotai and

16 Eszterhás and Szentes

Szentgáli Basins. Extensive Lajtha Limestone deposits represent the Middle Miocene in both the Western Bakony Mountains and in the Tapolcai Basin. Coarse-grained calcareous sandstone and conglomerate are to be found in the central and southern part of the mountains, and are significant as regards nonkarstic cave development. The topset beds of the basins are limnic sandy and claey sediments, which were deposited in the Upper Pannonian Stage of the Pliocene. In some places, quartziferous sandstone occurs, which is suitable for nonkarstic cave development. In the Upper Pannonian, intensive basalt volcanism has occurred, which has resulted in alkaline basalt and basalt tuff. Occasionally the basalt structure is scoriaceous. The witness buttes and tuff rings in the Tapolcai Basin and the basalt plateau of Mount Kab embellish the basalt landscape. In the Balaton Upland,

CAD. LAB. XEOL. LAXE 37 (2013)

various basalt tuff outcrops are to be found. As a result of numerous phases of volcanic activity, the thickness of the basalt formation varies from 50 to 200 metres. In the crater basins and in the depressions of the tuff rings, oil shale occurs, originating from the algae which have settled there. The post volcanic activity has created the geyserite in the Tihanyi Peninsula. The basalt, basalt tuff and the geyserite are the most significant of the rocks surrounding the non-karstic caves in the Bakony Mountains (Fig. 2). On the mountain sides, accumulated loess is the most characteristic formation from the Pleistocene. The soft deposit offers a suitable material to construct artificial caves and cellars, but one natural cavity is also known in the loess. Colluvium, redeposited tuff, fluvial sand and pebbles together with swamp deposits such as turf were deposited in the Holocene.

Fig. 2. Geological map of the surrounding rocks of the non-karstic caves in the Bakony Mountains

CAD. LAB. XEOL. LAXE 37 (2013)

NON-KARSTIC CAVE DEVELOPMENT IN THE BAKONY MOUNTAINS The petrographic structure of the mountains is very varied. As a consequence, the 1000 caves which are to be found show diverse appearance and development (BERTALAN, 1958; ESZTERHÁS, 1983, 1984). The majority of the rocks are karstic limestone and dolomite, therefore, approximately 85% of the caves are karstic. The most significant karstic caves are the 4000 m long Csodabogyós Cave, the 3600 m long Alba Regia Cave, the 2400 m long Cserszegtomaji Well Cave and the hydrologically important Spring Cave of Héviz. There are also numerous non-karsic caves. Within the framework of this study we cannot describe all of these caves. We only intend to present some examples

Geological sketch and the non-karstic caves 17

to show the diversity of the non-karstic caves. Up to 2011, 147 natural non-karstic caves and 35 artificial cavities have been listed in the Bakony Mountains. The total length of the natural non-karstic caves is 991 m. The longest caves are the 151 m long Pulai Basalt Cave (Fig. 6, Pict. 4), the 72 m long Halász Árpád Cave (Fig. 8) and the 51 m long Kapolcsi Pokol Hole (Fig. 5, Pict. 3). Eighty-four non-karstic caves have developed in sedimentary rocks such as sandstone, conglomerate, geyserite and loess, while 63 caves have formed in basalt and basalt tuff (ESZTERHÁS and SZENTES, 2004, 2009, 2010). The nonkarstic caves according to their development can be classified into 16 genotypes with four categories (ESZTERHÁS, 1993; OZORAY, 1960; SZENTES 2010) (Table I.).

18 Eszterhás and Szentes

CAD. LAB. XEOL. LAXE 37 (2013)

Genotypes of the Caves

Examples:

I. Syngenetic caves 1. Gas bubble cavities

Gas bubble cavity in the Castle Hill of Szigliget

2. Explosion Caves a) steam explosion caves 3. Caves in geyserite.

Explosion Cave near the village of Gödrös Tihanyi Spring Cave

II. Postgenetic Caves 1. Caves originated through mass movement a) Tectonic caves - Caves formed parallel to the rim of the outcropping rock - Caves developed perpendicular to the rim of the outcrop - Caves formed along the downcast faults of the basalt layers

Kapolcsi Pokol Hole Lower Cave of Kőudvar Pulai Basalt Tuff Cave

b) Atectonic caves

Vadlány Hole

c) Break up Caves

Pulai Basalt Cave

d) Consequence caves

Basalt Quarry Cave near the village of Badacsonytomaj

e) Talus caves

Little Sárkány Ice Cave

2. Fragmentation caves a)Caves originated through temperature and moisture variation - Fragmentation caves

Kő-hegyi Cave

- Cavities between basalt columns

Lépcső-menti Cave

3. Caves originated through chemical weathering a) Alkaline solution caves

Upper Hole of the Aranyház Geyser Cone in Tihanyi Peninsula

III. Complex cave development Gas bubble + Artificial

Halász Árpád Cave

Geysirite deposition + Alkaline solution

Csúcs- hegyi Spring Cave in Tihanyi Peninsula

IV. Artificial cavities

Cave Monastery in Tihanyi Peninsula

Table I.: Genotypes of the non-karstic caves in the Bakony Mountains

CAD. LAB. XEOL. LAXE 37 (2013)

The syngenetc cavities, which formed concurrently with the processes of the rock formation, belong to the first category. Three different types of syngenetic caves occur in the Bakony Mountains. Three gas bubble cavities open in the Castle Hill of Szigliget and on Mount Kab. Four caves are the result of a steam explosion and 41 caves have

Fig. 3. Survey of the Kő-hegyi Cave

Geological sketch and the non-karstic caves 19

developed concurrently with the geyserite deposition on the Tihanyi Peninsula. Only the central part of the geysirite, caves are syngenetic, their further cave development due to alkaline solution. Unfortunately, 20 geyser cones with caves were demolished for building material in the first part of the 20th century.

20 Eszterhás and Szentes

Fig. 4. Survey of the Tihanyi Spring Cave

CAD. LAB. XEOL. LAXE 37 (2013)

CAD. LAB. XEOL. LAXE 37 (2013)

Fig. 5. Survey of the Kapolcsi Pokol Hole

Geological sketch and the non-karstic caves 21

22 Eszterhás and Szentes

Most of the non-karstic caves have postgenetic origin and show various genotypes. The tectonic caves originated through mass movement, and were formed as a result of the shifting of the rock masses. Thirty-four tectonic caves are known in the Bakony Mountains. The basalt surface forms steep rims, because of the intense denudation of the surrounding sediments. As a consequence of that, the basalt layer lost the support and cracks are forming in the basalt. The cracks develop into caves after the further denudation of the sediments. Finally, some rims break down and collapse. Three different orientations of the potential cave developing cracks can be distinguished, in consequence of that three different types of tectonic caves are to be found. These are the caves which have developed perpendicular to the rim of the outcrop, caves which have formed parallel to the rim of the outcropping rock

CAD. LAB. XEOL. LAXE 37 (2013)

formation, and caves have formed along the downcast faults of basalt layers. Twentyone tectonic caves have formed parallel to the rim of the outcropping rock in the Bakony Mountains. The most significant are the 51 m long Kapolcsi Pokol Hole (Fig. 5, Pict. 3), the 39 m long Remete Cave near the village of Zalaszántó and the 26 m long Araszoló Cave. Twelve tectonic caves have developed perpendicular to the rim of the outcrop. The denudation of certain parts of the basalt rims varies. The blocks which denudate faster, down fault and separate themselves from the neighbouring basalt layers, forming perpendicular faults to the rim. The dilatation of the dominant faults results in this type of tectonic caves. Such caves include the Lower Cave of Kőudvar, the Gyöny-tavi Cave near the village of Köveskál and probably the partly collapsed Bél-féle Sárkány Cave. The Pulai Basalt Tuff Cave has formed by the downcast faults of basalt layers.

Pict. 1. Entrance to the Csúcs-hegyi Spring Cave in the geyser cone

CAD. LAB. XEOL. LAXE 37 (2013)

Atectonic caves were formed by the dilatation of the cracks as the rock mass moved down the slope. Five of these caves can be observed in the Basalt Street on Mount Kovácsi. From the rim, basalt blocks have separated off, and are sliding down on the convex slope of the sandstone and marl surface. The sliding induces cracks in the basalt blocks, which can widen into cave size as they slide further. Caves originating from such dilatation are the 24 m long Vadlány Hole (Fig. 7. Pict. 5.), the 12 m long

Geological sketch and the non-karstic caves 23

Kőkamra and the 7 m long Basalt Street Niche. Break up Caves form when the roof of a cavity loses its stability and collapses partly or completely due to the lower layers being washed out. The original cavity becomes filled with debris and in the upper part develops a new hollow, the so-called break up cave. The most significant break up cave in the Bakony Mountains is the 151 m long Pulai Basalt Cave (Fig. 6, Pict. 4) (ESZTERHÁS, 1986).

Pict. 2. Remains of the Explosion Cave of the Castle Hill of Szigliget

The consequence caves are a particular example of caves which have originated through collapse. The natural collapse of ceilings in artificial cavities (mine, cellar, dungeon) may form apparently natural

holes in the higher elevations of a system. In the Bakony Mountains, only one consequence cave is known, the 3 m long Basalt Quarry Cave near the village of Badacsonytomaj.

24 Eszterhás and Szentes

CAD. LAB. XEOL. LAXE 37 (2013)

Pict. 3. Kapolcsi Pokol Hole

Pict. 4. Pulai Basalt Cave, in the background disc-shaped isingerit can be seen on the wall

CAD. LAB. XEOL. LAXE 37 (2013)

Three talus caves represent the pseudocaves in the Bakony Mountains. The Little Sárkány Ice Cave and the Big Sárkány Ice Cave on Mount Szent György and the Gyöngy- tavi Pseudocave near the village of Köveskál are to be found between the accumulated basalt blocks below the basalt rims. Fifty-four caves have developed through fragmentation in the Bakony Mountains. Fragmentation through temperature and moisture variation attacks the basalt, the sandstone and the conglomerate, which results in smaller caves and rock shelters. Thirty-seven caves have formed through typical fragmentation. The rock forming minerals react to altering physical influences (temperature, moisture) with different volumetric expansions, which cause tiny cracks, then holes which occur in the place of fragmenting minerals. These type of fragmentations are to be found in Kő-

Geological sketch and the non-karstic caves 25

hegyi Cave (Fig. 3) near the village of Szentbékálla, in the Kerek-kő Cave near the settlement of Gyulakeszi, which has developed in sandstone and in Northern Cave near the village of Ajkarendek which has formed in conglomerate. The specific fragmentation of the basalt forms cavities between basalt columns. These are narrow, high caves or shafts. Seventeen cavities between basalt columns are listed among the basalt columns of the rims. In Mount Szent György, the Lépcső-menti Cave (Pict. 7) and the Kilátó-alatti Cave, in Mount Badacsony the Hedera Cave, the Cirmos Cave and in Mont Somlyó the Sziklakonyha Cave are to be found between the basalt columns. In Mount Tátika, the Fekete-oszlopos Cave has formed between the basalt colums which have slid apart. In the Bakony Mountains, it is difficult to separate the cave development originating from altiplanation, from that origination from fragmentation.

Pict. 5. Basalt blocks in Vadlány Hole

26 Eszterhás and Szentes

Fig. 6. Survey of the Pulai Basalt Cave

CAD. LAB. XEOL. LAXE 37 (2013)

CAD. LAB. XEOL. LAXE 37 (2013)

Chemical weathering has resulted in the formation of different types of solution caves. Acidic solution, which forms cavities in karstic rock, is not the subject of the present study. The non-karstic rocks (basalt, geyserite, sandstone) contain large amounts of silicate. In the nature, the resulting acid can not dissolve the siliceous material. Solution is only possible in an alkaline environment. The lye on the surface or in the subsurface zone can originate from postvolcanic activity or, rarely, from the decomposition

Fig. 7. Survey of the Vadlány Hole

Geological sketch and the non-karstic caves 27

of the organic acids. Alkaline solution has been partly responsible for the formation of what were originally syngenetic geysirite caves in the Tihanyi Peninsula. The geysirite formation is diverse as regards the deposition and the chemical reactions of the solutions. The precipitated and consolidated silicate (geysirite) dissolves, if the pH value of the solution exceeds 8. Accordingly, solutions over pH8 produce geyser activity in the 41 geyserite caves alkaline solution occurred (ESZTERHÁS, 1987-b).

28 Eszterhás and Szentes

Another cave development category is the complex cave development. It is possible in each individual caves to detect several cave forming factors. Nevertheless, it is necessary to create a category where the presence of several cave forming factors are approximately equivalent. In this case, it is difficult to define the main factor. Such a cave is the 72 m long Halász Árpád Cave (Fig. 8) on Mount Kab. The cave is partly artificial because a series of gas bubble cavities have connected to the tunnel of a mining company. We can also include here the geysirite caves in the Tihanyi Peninsula, which have formed partly syngenetically with geysirite deposition and partly postgenetically by alkaline solution. Some artificial cavities are considered to be caves by the local population. In the Bakony Mountains, 28 cave-dwellings in loess have been listed. Nineteen of these cave-dwellings have collapsed, only 9 cavities of the Tatár Holes near the village of Balatonkenese are still in existence. In the Tihany Peninsula, a Cave Monastery was carved in the basal tuff nine centuries ago. Seven cavities of the monastery can still be seen. DESCRIPTION OF SOME CHARACTERISTIC CAVES ACCORDING TO THE TYPES OF CAVE DEVELOPMENT AND THE SURROUNDING ROCK The present study has selected and reviews the 18 most significant and characteristic caves of the 147 natural nonkarstic caves and 35 artificial cavities in the Bakony Mountains. Ten caves open in sandstone. Each of the 10 sandstone caves have developed by fragmentation through temperature and moisture variation. A peculiar surface

CAD. LAB. XEOL. LAXE 37 (2013)

formation, the “Stone Sea” of Mount Kő is to be found at 207 m above the sea level to the west of the village of Szentbékálla. Here the most characteristic rock figure is the Kelemen Stone. The covering rock slab of the stone formation is subject to movement. The 2.5 meter wide and 90 cm high entrance to the Kő-hegyi Cave (Fig. 3.) opens in the south-western side of Kelemen Rock. The cave is a 3.25 m long gradually narrowing, lenticular niche. The surrounding rock is Pannonian siliceous sandstone. The cementation of the sandstone is uneven. The fragmentation of the loosest part of the sandstone has resulted in a cave. In several locations of the Bakony Mountains, calcareous or siliceous conglomerate occurs. Thirty-two small caves are known in conglomerate formation. Mount Ajka near the village of Ajkarendek is composed of Miocene marly limestone, which is overlain by Upper Pliocene marly, limy quartz and limestone pebble conglomerate. Three caves are to be found in the conglomerate at the boundary between the two rock layers. The most characteristic is the 6.5 m long crawling passage of Northern Cave. The cave development began with the formation of a cavity through the loosening and eroding of the underlying sediments. The resulting small cavities in the fragmented conglomerate, gradually formed into larger cavities. Geysirite occurs mainly on the Tihanyi Penninsula. Smaller outcrops of geysirite are located in the Koloska Valley and near the village of Pula. It is reputed that originally 130 – 150 geyser cones existed on the Tihany Peninsula. Seventy-nine cones were identified in 1983, but many of them were partly demolished (ESZTERHÁS 1987-b). Since the development of the

CAD. LAB. XEOL. LAXE 37 (2013)

geyserites, caves are dependent on the geyser cones, many of these caves are the victims of quarry operations. Recently, 22 geyserite caves or the ruins of geyserite caves were identified. The most important caves are the Csúcs-hegyi Spring Cave and the Tihanyi Spring Cave. The Tihanyi Spring Cave is a gated show cave (Fig. 4). The fourteen metre long cave is composed of two chambers and two bigger niches. The walls are decorated with spectacular solution forms, which also form the vault of the ceiling. In the first chamber, two striking joints and a layered hydroquartzite formation overlain by compact limy-siliceous geyserite can be observed. Some solution forms are covered with secondary calciferous coatings. Near the cave entrance and in the second chamber, walnut and apple-sized opal concretions can be seen. The artificial widening in the cave crops out nicely the structure of the geyser cone. The Csúcs-hegyi Spring Cave (Pict. 1) opens in the Tihanyi Peninsula in the western side of Mount Nyereg. The entrance to the cave is 3.2 m high and 2.7 m wide. Behind the entrance runs a 4.2 m long and 3 m wide oval chamber. There is no vaulting, in the wall only minor salient and flares appear. From the chamber a 6.5 metre high and 20 – 25 cm diameter chimney opens to the surface. Between the chimney and the cave entrance a 4.3 m high blind chimney rises. The surrounding geysirite is made up of cellular hydro-quartzite with minor lime content. Compact chalcedony occurs in a 3-4 m section of the chamber. On the hydroquartzite surface solution forms, there are traces of the cave having developed in an alkaline solution. Fifty-six caves have formed in the alkaline basalt in the Bakony Mountains.

Geological sketch and the non-karstic caves 29

We describe the most characteristic ten basalt caves. Two gas bubble cavities formerly existed in the basalt dyke of Castle Hill at Szigliget Village. One of the cavities has been completely demolished. The remains of the other cavity in columnar basalt, the so-called Explosion Cave of Castle Hill of Szigliget (Pict. 2) still exists (ESZTERHÁS, 1987-a). The surface of the bell shaped, 130 cm long hole is perfectly smooth. An 85 cm long syncline in the foreground indicates the original 215 cm length of the cavity. At the end of the hole, a 5-6 cm diameter tube dipping down at an angle can be observed, which probably marks the place of inflow of the blowing gases. The 51 metre long Kapolcsi Pokol Hole (Fig. 5, Pict. 3) has formed parallel to the rim of the outcropping basalt (ESZTERHÁS, 1984-a, 1985). The basalt is underlain by a loose sandstone layer and its rim has broken away. The basalt blocks have not slid down on the slope, but leant against the bedrock, forming a tectonic cave, which is parallel to the verge. In the sandstone, thick basalt blocks dam up the seeping water, which emerges in the cave as a spring. This spring feeds a small lake. The size of the lake varies, because after the water reaches a certain level a siphon system drains it. On the western slope of Mount Tátika there is a similar original tectonic cave, the 39.2 m long Remete Cave. Behind the 1.2 m wide and 3 m high entrance a gradually narrowing, funnel-shaped corridor leads to the high and narrow main passage. The vertical extent of the cave is 20.4 m, but the average width is only 40-50 cm. The cave wall is composed of columnar basalt. The basalt columns are coated with white calcite speleothems, which stems from the

30 Eszterhás and Szentes

overlaying calcareous sand (ESZTERHÁS, 1987-a). The Lower Cave of Kőudvar is to be found also in Mount Tátika. Behind the 1 m high and 60 cm wide entrance runs a 5.1 m long crawling passage. The significance of the cave is the perpendicular development to the rim of the basalt outcrop (ESZTERHÁS, 1988-a). The 151 meter long and 21 m deep Pulai Basalt Cave (Fig. 6, Pict. 4) is a break up cave (ESZTERHÁS, 1985). The 25-30 m thick basalt is underlain by soluble limestone. Along the cracks in the basalt, seeping water has dissolved holes in the limestone, into which the basalt layer has broken. The cave is accessible through a narrow shaft, which leads to a bigger chamber. From this chamber various small passages and shafts open in different directions. The cave wall shows nicely the different basalt layers, which are the witness to the several thousand years of volcanic activity. In the cave, a rare silicate mineral can be found, the disc-shaped isingerit.

CAD. LAB. XEOL. LAXE 37 (2013)

The atectonic Vadlány Hole (Fig. 7, Pict. 5) is the most remarkable cave on the Mount Kovácsi. The irregular quadrangular entrance shaft to the cave is a 45 degree slope, which is divided into two openings by a jammed rock slab. Beneath the shaft a 2.7 m wide chamber opens out, which continues in a 6.8 m long, 1 m wide and 2 – 2.8 m high rectangular Entrance Passage. The walls are composed of fragmented gray basalt. The cave belongs to the atectonic development group of the postgenetic caves (ESZTERHÁS, 1988-b; OZORAY, 1960; SZENTES, 1971). The depths of the cave have formed concurrently with the Basalt Street on the surface. The basalt layer lost its support, tipped out and slid down on the concave slope. This movement has generated parallel and perpendicular expanding cracks to the main strike of the Basalt Street. One of the perpendicular cracks forms the longitudinal extent of the cave and several smaller parallel cracks can be observed in the wider parts of the cave.

CAD. LAB. XEOL. LAXE 37 (2013)

Geological sketch and the non-karstic caves 31

Pict. 6. Ice formations in summer in Big Sárkány Ice Cave

Pict. 7. Lépcső-menti Cave between the basalt columns in Mount Szent György

The Basalt Quarry Cave near the village of Badacsonytomaj is to be found in the wall of an abandoned basalt quarry. The cavity is a 5 m wide and 2.4 m high niche. The embayment of the hole is 2.9 m. The small cavity is the only consequence cave in the Bakony Mountains. The hole was created by a break down during quarry operation. The Little Sárkány Ice Cave opens on the northern side of Mount Szent György between the debris of collapsed basalt columns (ESZTERHÁS, 1994-b). The entrance to the cave is 2 m wide and 1 m high. The zigzag labyrinth is passable for a length of 6.7 m. The cave is a so-called dynamic ice cave. In the summer season (March-September), the temperature of the outward flowing air is below freezing point, therefore, the condensed water gets cold

enough to form an ice crust on the basalt blocks. The speed of the outward flowing air is 5 – 15 m/sec, which spasmodically speeds up sometimes in every few minutes. In winter, the inflowing air does not cause ice coating. Nearby, in the 31 m long Big Sárkány Ice Cave the ice coating can similarly be observed (Pict. 6). The cavities between basalt columns are specific fragmentation caves of the basalt rims. With favourable climatic and petrographic conditions the basalt rim can sometimes form 20-30 m high columns. The fragmentation results in single columns, which collapse later in the ultimate stages of their development. If the gravel can trickle from between the gaps in the columns, then high, narrow cavities form. Seventeen cavities between basalt columns have been

32 Eszterhás and Szentes

listed in the Bakony Mountains. Most of them are to be found on Mount Szent György, for instance the 37 degree sloping, 2.3 m long and 7.6 m high Lépcső-menti Cave (Pict. 7). One of the most significant non-karstic cave in the Bakony Mountains is the Halász Árpád Cave (Fig. 8). Halász Árpád was a geologist and cave explorer in the region. The cave is a 72 m long horizontal passage 4-5 m beneath the surface. Two shaft entrances lead to the cave (ESZTERHÁS 1988-c). The cave is filled with water up to the entrance shafts for the greater part

CAD. LAB. XEOL. LAXE 37 (2013)

of the year, only in a very dry summer is 20-25 m passable in the upper section. A complete study was carried out in the year 1987, after pumping the water out from the cave. The results have not clearly proved the origin. Probably, the holes were a range of gas bubble cavities, which were connected artificially during the mining operation and were used as a shelter and a store. In some places on the wall ropy lava formations and conical lava speleothems can be seen. After the mining operations were abandoned, groundwater has filled up the cavities.

Fig. 8. Survey of the Halász Árpád Cave

In the basalt tuff, 7 caves have been listed. The most interesting is the Explosion Cave near the settlement of Gödrös. The 3 m high and 1.5 m wide entrance to the cave opens in the wall of an abandoned quarry. The 6.5 m deep cave is a 16 m long maze. The basalt tuffite walls were decorated

with 3-4 mm sized calcite pizolites, which have been completely looted. The cave has developed through steam explosion (ESZTERHÁS, 1988-c). Due to a decrease in pressure, the streaming hot water, which was of volcanic origin and travelling upwards, suddenly volatilized.

CAD. LAB. XEOL. LAXE 37 (2013)

The consequent explosion stretched apart the loose, pyroclastic rock. In this way, an irregular-shaped hole was formed which was filled with a hot solution. From this solution precipitated minerals cemented the walls of the hole and deposited the calcite pizolite coating. The cave, which originally

Geological sketch and the non-karstic caves 33

had no surface connection, was opened by quarry operations in 1930. The Pulai Basalt Tuff Cave opens near the highway between the towns of Veszprém and Tapolca. The 10 m long low, but wide crawling passages of the cavity have been formed by the downcast faults of basalt layers.

Fig. 9. Survey of the No. 2 Monk’s Dwelling in the Tihanyi Peninsula

34 Eszterhás and Szentes

CAD. LAB. XEOL. LAXE 37 (2013)

Pict. 8 Monk’s Dwelling in Tihanyi Peninsula

As well as the 35 artificial cavities in the Bakony Mountains it is worth considering the Cave Monastery, the socalled monk’s dwellings (Pict. 8.), which have been carved in the basalt tuffite of the Tihanyi Peninsula (ESZTERHÁS, 1987b; MEDNYÁNSZKY, 2009). The No. 2 Monk’s Dwelling (Fig. 9) is a complex hole. The base area of the 3 m high main chamber is 6 x 3.5 m. Behind the chamber a 2.5 x 1.3 m sized cell opens where a carved grave is to be found in the bottom. In the MiddleAges, between the years 850 and 1350 active religious life took place in the monastery. Orthodox hermits from Greece lived here, and hollowed out their reclusories, chapel and dining-room. Later, the monastery was abandoned and through the centuries

was devastated by collapses and looting. Recently, as a scheduled monument, the ruins have been partly renovated. Near the village of Balatonkenese there were once 28 holes carved in the loess wall, but today only nine cavities remain. The local people call them Tatár (Tartar) Holes, however, their origin most probably is not from the age of the Tartar Invasion (1241-42), and this is just a folk tale (MEDNYÁNSZKY, 2009). The cavities were mentioned first in the year 1676. The biggest hole is the No. 7 Tartar Hole. The hole consists of two chambers, one 6 m long and the other 5 m long. Memorials and wall scrapes identify many cavity-dwellers and at the present time the hole is used as an occasional bivouac place.

CAD. LAB. XEOL. LAXE 37 (2013)

SUMMARY The Bakony Mountains are the most complex geological region in Hungary. The mountains are composed of numerous sedimentary (chemogenic, clastic, and biogenetic) and volcanic (basalt and basalt tuff) rock formations. As a consequence, the speleology of the region is diverse. There are a large number of horizontal and vertical, wholly or partly flooded, cold or thermal water originating karstic caves. The non-karstic caves, which number 147, have developed through gas bubble, steam explosion, and geyserite deposition. There are also tectonic, atectonic, break up, talus, fragmentation and alkaline solution originating non-karstic caves. Some of them are flooded and two of them have ice coating. BIBLIOGRAPHY BERTALAN, K. (1958). Magyarország nem karsztos eredetű barlangjai (Nonkarstic Caves of Hungary) - Karszt- és Barlangkutatási Tájékoztató (jan-jún), Budapest: p.13-21. BUCKÓ, E. (1970). A Tihanyi-félsziget geomorfológiája, In Bialik: Magyarázó a Balaton környéke 1:10.000 építésföldtani térképsorozatához – Tihany. (Geomorphology of the Tihanyi Peninsula, In Bialik: Explanatory Note for the Engineering Geological Map of Lake Balaton Region – Tihany, 1 : 10 000) Hungarian Geological Survey Publication, Bp. 1970. p. 47-55. CHOLNOKY, J. (1931). Tihany, morfológiai megfigyelések (Morphological Observations In Tihany Peninsula) Matematikai és Természettudományi

Geological sketch and the non-karstic caves 35

Értesítő (48. köt. 1. füzet), Budapest p. 225- 227. ESZTERHÁS, I. (1983). A Bakony barlangjai (Caves of the Bakony Mountains) - in Mészáros: Bakony, Balaton-felvidék - Medicina Könyvkiadó, Budapest p. 45-71. ESZTERHÁS, I. (1984). Lista a Bakony barlangjairól (List of the Caves in the Bakony Mountains) - Folia musei historico-naturalis Bakonyiensis, Zirc p. 13-30. ESZTERHÁS, I. (1985). A Kapolcsi Pokollik (The Kapolcsi Pokol Hole) - Folia musei historico-naturalis Bakonyiensis, Zirc p. 39-42 ESZTERHÁS, I. (1986). A Pulaibazaltbarlang és környéke (The Pulai Basalt Cave and its surrounding)- Karszt és Barlang (I. füzet), Budapest p. 23-32. ESZTERHÁS, I. (1987-a). A Bakony bazaltbarlangjai (Basalt Caves in the Bakony Mountains) - Föld és Ég (22. évf. 12.sz). Budapest p. 360-364. ESZTERHÁS, I. (1987-b). A Tihanyifélsziget barlangkatasztere (List of the Caves in the Tihanyi Peninsula) – Bakony Természettudományi Kutatásának Eredményei (18. köt). Zirc p. 1-84. ESZTERHÁS, I. (1988-a). A Tátika bazaltbarlangjai (Basalt Caves in Mount Tátika) – Folia musei historico-naturalis Bakonyiensis (7. sz.) Zirc, p. 13-22. ESZTERHÁS I. (1988-b): A Kovácsi-hegy bazaltbarlangjai (Basalt Caves in Mount Kovácsi) Folia musei historico-naturalis Bakonyiensis (7. sz), Zirc, p. 23-36. ESZTERHÁS, I. (1988-c). A magyarországi bazaltbarlangok kutatottságának eredményei (Results of Basalt Cave Research in Hungary) – Karszt és Barlang (1988 I. füzet), Budapest p. 15-20.

36 Eszterhás and Szentes

ESZTERHÁS, I. (1984-a). A Pokol-lik (The Pokol Hole) – Lychnis, a Vulkánszpeleológiai Kollektíva kiadványa, Kapolcs p. 28-35. ESZTERHÁS, I. (1984-b). Magyarország jégbarlangjai (Ice Caves in Hungary) – Lychnis, a Vulkánszpeleológiai Kollektíva kiadványa, Kapolcs p. 36-42. ESZTERHÁS, I. (1993). Genotypes of caves in volcanic rocks in Hungary – Conference on the karst and research activities of educational and research institutions in Hungary, Jósvafő p. 81-86. ESZTERHÁS I. and SZENTES, G. (2004). Magyarország nemkarsztos barlangjainak katasztere – (A List of Non-karstic Caves in Hungary) http//:geogr.elte.hu/nonkarstic ESZTERHÁS, I. and SZENTES, G. (2009). Overview of the Non-karstic Caves in Hungary, 15th International Congress of Speleology, Kerrwille, Texas, USA 2009, Proceedings, Vol. 3, p.1474 - 1480 ESZTERHÁS, I. and SZENTES, G. (2010). Caves formed in Volcanic Rock in

CAD. LAB. XEOL. LAXE 37 (2013)

Hungary, Part I-II., XIV. Syposium on Vulcanspeleology, Queensland, Australia 2010, Proceedings, p. 179-196. GYALOG, L. (2005). Magyarázó Magyarország fedett földtani térképéhez, 1:100 000 (Az egységek rövid leírása), (Explanation Note for Geological Map of Hungary, 1 : 100 000, Short descriptions of the units) Budapest, Hungarian Geological Survey. JUHÁSZ, Á. (1987). Évmilliók emlékei – (Relics from Millions of Years) Gondolat Kiadó, Budapest p. 1-562. OZORAY, G. (1960). The genesis of non-karstic natural cavities as elucidated by Hungarian examples –Karszt- és Barlangkutatás (II. kötet), Budapest p.127-136. MEDNYÁNSZKY, M. (2009). Magyarországi barlanglakások (Cave-dwellings in Hungary) – TERC Kereskedelmi és Szolgáltató Kft. Budapest p. 89-91, 177- 182. SZENTES, G. (1971). Caves formed in the volcanic rocks of Hungary – Karszt- és Barlangkutatás (VI. kötet), Budapest p. 117-129.

Cadernos Lab. Xeolóxico de Laxe Coruña. 2013. Vol. 37, pp. 37 - 56

ISSN: 0213-4497

First data on testate amoebae in speleothems of caves in igneous rocks

González López, L.1, Vidal-Romaní, J.R. 1, López Galindo, M. J.1, Vaqueiro Rodríguez, M.1 and Sanjurjo Sánchez, J.1

(1) Instituto Universitario de Geología. Universidad de Coruña, 15071 Coruña, Spain. Corresponding author email address: [email protected]

Abstract The testate amoebae form part of the habitual troglobios in caves developed in igneous rocks (plutonic and volcanic) where the little light, the persistence of humidity, the availability of silica and organic matter allow these protozoa to develop their biological cycle. This work presents a first inventory of species of amoebae testate identified in caves in igneous rocks from different parts of the World. Key words: testate, caves in igneous rocks, amorphous opal speleothems.

38 González et al.

INTRODUCTION Massifs formed by igneous rocks are characterized by their low porosity and scarce solubility, so in these cases runoff normally moves on the surface. However, runoff may drain exceptionally underground through the systems of cavities related to fractures, faults or diaclases when they are open totally or partially. When these types of caves are very large they are considered pseudokarstic systems as they are developed in non soluble rocks and are also differentiated from the karst sensu sctricto, characteristic of calcareous massifs (VIDAL ROMANÍ & VAQUEIRO 2007; Vidal Romaní et al., 2110 a y b). Pseudokarst is also distinguished because water circulation is normally produced at low velocity as trickles which disperse slowly onto the floor, walls or ceiling of the caves. In physical continuity with these trickles, it is normal to find specific deposits (speleothems) of small dimensions and characterized by a varied mineralogical spectrum, the most frequent mineral species being: amorphous opal, evansite, pigotite, alophane, or even carbonates (FORTI, 2005; VIDAL ROMANÍ et al., 2110 a y b). These types of speleothems were first described by Caldleugh in 1829, and during a long time it was considered that they were due to the rock weathering produced by the water (VIDAL ROMANÍ et al., 1979; VIDAL ROMANÍ, 1983; VIDAL ROMANÍ & VILAPLANA, 1984; WEBB & FINLAYSSON, 1984). For this reason, these deposits were first characterized almost exclusively by their mineralogy ignoring their relationship with the activity of microorganisms which lived in these caves. Later, the introduction of the scanning electronic microscopy in the

CAD. LAB. XEOL. LAXE 37 (2013)

study of these speleothems (KASHIMA et. al, 1987; VIDAL ROMANÍ et al. 1984, 1988) has showed the existence of a close relationship between the troglobiotic activity carried out by cyanobacteria, diatoms, testate amoebae, fungi, etc., and the formation of these deposits (justifying the name of biospeleothems that some authors give to them (Forti, 2001; VIDAL ROMANÍ et al., 2110 a y b)). Obviously, the greater volume of water and also its greater persistence inside a cave, when compared to what takes place outside, allow to originating the necessary conditions for the development of microorganisms (BASTIAN et al., 2009; SAIZ-JIMÉNEZ et al., 2011) transforming these caves (given their scarce light, abundance of organic matter and availability of silica) into a suitable habitat for the testate amoebae (VIDAL ROMANÍ et al., 2110 a and b). Though a significant microbiological activity exists in the karstic environment sensu stricto (NORTHUP & LAVOIE, 2001), the great abundance of water makes the physical processes, especially chemical, prevail with the corresponding formation of speleothems (by dissolutionprecipitation), even inhibiting the processes developed by the microorganisms that need more stable and quite environments, and essentially a slower water dynamics. Perhaps the best demonstration of what happens with the microorganisms in karstic and pseudokarstic environments is the same existence of testate amoebae, characteristic of the pseudokarst, whose tests are so small and delicate that they do not resist a short transport process and are simply destroyed by the change of the humidity conditions inside the cave, undoubtedly causing the death of the protozoan and the immediate dismemberment of its test. For the specific

CAD. LAB. XEOL. LAXE 37 (2013)

case of the pseudokarstic environments developed in massifs of igneous rocks, the organic activity influences on the formation of the biospeleothems in two phases: first, the destruction of the silicates of the rock which are dissolved in the infiltration water and second, the generation of speleothems, especially those containing amorphous opal

First data on testate amoebae in speleothems 39

(VIDAL ROMANÍ et al., 2110 a y b), when Si dissolved in water precipitates due to the oversaturation by evaporation when the water contribution to the systems ends. In this work, we refer generically to all the igneous rocks grouped in 4 sets whose chemical and mineralogical compositions may vary substantially (Table 1).

Table 1 . Types of igneous rocks (intrusive and extrusive) with their mineralogical composition and percentage of SiO2.

As it may be observed in the acid and intermediate rocks, silica is one of the most abundant chemical element (ranging between 50 and 80%), which explains that the amorphous opal is the most frequent mineralogy of these speleothems, but not the only one, in caves of these types of rocks. On the contrary, the proportion of silica in the basic and ultrabasic igneous rocks is lower (ranging between 50 and 30%), and in these cases it may happen that amorphous opal speleothems

are scarce, do not form, or even coexist with calcium carbonate speleothems (WOO et al., 2008; BEINLICH & AUSTRHEIM, 2012; OKLAND et al., 2012). TESTATE AMOEBAE Amoebae are protozoa or unicellular organisms that may live either naked or protected by a test both in subaerial or subterranean environments. The test may

40 González et al.

be formed by secretations of proteinaceous type, or by plates of calcite, amorphous silica (idiosomes), and in the agglutinated amoebae by mineral or organic particles like pollen grains, plates of other amoebae, or remains of other microorganisms (diatoms, collembolan, etc.) (Fig. 1) which share the subterranean environment. There is a lot of literature on amoebae species in calcareous caves (WOO et al., 2008; BEINLICH & AUSTRHEIM, 2012; OKLAND et al., 2012) though normally referred to as naked amoebae which, together with other organisms, form part of the stygobios that lives in the water mass which circulates through the cave. This work is a study of the troglobites from caves in igneous rocks,

CAD. LAB. XEOL. LAXE 37 (2013)

focussed on testae amoebae that appear in the sedimentary registry (speleothems) preserved in these caves. In caves developed in igneous rocks, amoebae segregate plates of amorphous silica (idiosomes) with a specific spatial distribution pattern, size or geometry (Figs. 2 and 3). Some species develop spines on their tests perhaps to ensure their stability on the speleothem surfaces when water seeps over them (Fig. 4). Testate amoebae, also those with amorphous silica idiosomes, are not exclusive of caves in igneous rocks and are represented in subaerial environments: free continental waters (rivers, lakes, springs), soils, peat bogs or biofilms developed over tree barks (WYLEZICH et al., 2002).

Fig.1. Amphitrema wrightianum (?) Berrocal del Rugidero, Badajoz, Spain. Fig. 2 Idiosomes of Tracheleuglypha dentata. Porteliña, Galicia, Spain. Fig. 3 Idiosomes of Euglypha rotunda. Peña del Hierro, Huelva, Spain. Fig. 4 Euglypha strigosa. Austria

CAD. LAB. XEOL. LAXE 37 (2013) First data on testate amoebae in speleothems 41

Fig. 5. Different species of testate amoebae. Porteliña, Galicia, Spain. A-C-D: Trinema linare; B: Euglypha rotunda

42 González et al. CAD. LAB. XEOL. LAXE 37 (2013)

CAD. LAB. XEOL. LAXE 37 (2013)

An amoeba’s test has a flask-shaped form and is 100 µm long and maximum 50 µm width though the ones studied in our work are larger (Fig. 5). In one of the edges, there is an opening (pseudostome) frequently located on the narrowest part of the test with a border of very varied morphology (Figs. 6, 7 and 8) where there are the pseudopodia used to trap aliments and to move the protozoan. This pseudostome may be surrounded by modified plates which contain one or several teeth (Fig. 9). Sedimentary environments with acid pH, either caves in igneous rocks or superficial environments, are characterized by the weak drainage energy and bad water retention during the dry period, causing very quick environmental changes from wet to dry in very short time intervals. Perhaps that is why the organisms which colonize these environments, in our case the testate amoebae, develop strategies to survive draught preserving the humidity as well as to defend themselves from other predatory organisms. MATERIAL AND METHODS In this work, the results of the study of samples from caves in igneous rocks from different parts of the World (Spain, Portugal, Austria, Sweden, Argentina, Swaziland, Madagascar, Western and South Australia) are presented. In most of the study cases, specimens of testate amoebae associated to speleothems were identified. The samples were conveniently protected in bags or boxes depending on their fragility grade and dimensions to avoid their physical deterioration during their transportation to the laboratory. Once in the laboratory, they were examined, without previous treatment, at the stereoscopic microscope Nikon SMZ1500

First data on testate amoebae in speleothems 43

and photographed with a Nikon DS.Fi1 in order to select the best specimens. For their observation under the SEM, they were prepared according to the standard protocol which consisted in a not very aggressive desiccation (they were stored during a week in a vacuum desiccator of silica-gel) so as to avoid the production of artifacts, essentially the polygonal cracking of the amorphous opal layers. After their desiccation, the samples were metalized by spattering with a thin gold layer of 50-100 Å with cathode pulverization equipment BAL-TEC SCD 004. The use of carbon spattering was avoided because the normal analytic determinations in this type of sample could have masked the carbon content of some of the very abundant organic remains (palynomorphs, mites, collembola, bacteria, etc.). The samples thus prepared were studied under the scanning electronic microscope JEOL JSM 6400 selecting different magnification levels to locate and identify the organic and mineral elements in each studied sample. The sedimentary mineralogy, texture and structure of the samples were taken into consideration only as complementary information to define the dynamics and biogeochemical conditions of the environment. An inventory of the different species of amoebae identified in the speleothems is presented herein. The aspect of these protozoa is very much influenced by the time elapsed between the cave water appearance and the observation moment, obviously better preserved when the sample was taken during or immediately after the wet period of the cave. The amoebae were located on the external surface of the speleothems protected in small depressions or in the open voids of the porous fabric of the speleothem (Figs. 10 and 11). Their preservation state depends on

Fig. 6. Euglypha rotunda. Porteliña, Galicia, Spain. Arrow: pseudostome. Fig. 7 Tracheleuglypha dentata. Ávila, Spain. Arrow: pseudostome. Fig. 8 Trinema complanatum. Porteliña, Galicia, Spain. Arrow: pseudostome. Fig. 9 Pseudostome with toothed idiosomes of Euglypha rotunda (arrows) Porteliña, Galicia, Spain

44 González et al. CAD. LAB. XEOL. LAXE 37 (2013)

CAD. LAB. XEOL. LAXE 37 (2013)

whether the sample was collected during the wet stage when all the amoebae were alive and the test was intact, or during the dry stage when the test could be disintegrated totally or partially. In the transition stage from dry to wet, it was observed the colonization, in different grades, of the test by cyanobacteria which could cover them completely (Figs. 12, 13 and 14). According to this interpretation, different transformation states are distinguished: intact located on the speleothem surface (Figs. 4, 6, 7 and 8) or in different destruction phases with the test partially collapsed by flattening (Figs. 15 and 16) or totally dismantled with release of idiosomes, which are gradually

First data on testate amoebae in speleothems 45

incorporated into the speleothem as elements of its sedimentary fabric (Fig 17). They may appear as isolated individuals, in sets of several specimens (not necessarily of the same specie) (Figs. 5 and 18), sometimes of different sizes (Fig. 5) and also physically associated apparently (Fig. 13 and 19). In caves developed in igneous rocks, two big types of speleothems are distinguished: flowstone (Fig. 20) and cylindrical (Figs. 21 and 22) (VIDAL ROMANÍ et al., 2010 a and b) which will deposit indistinctly on the ceiling, wall or floor of the caves. Specimens of testate amoebae were found in both types of speleothems, though in greater quantity in the cylindrical ones (Figs. 21 and 22).

Fig. 10. Trinema enchelys protected in holes of the porous granular fabric. Trapa, Galicia, Spain. Fig. 11 Corythion dubium included in the polymineral granular material. Hölick Grotta, Sweden. Fig. 12 Trinema sp. with cyanobacteria covering its test. Trapa, Galicia, Spain Fig. 13 Set of Trinema sp. with cyanobacteria covering its test. Trapa, Galicia, Spain

46 González et al. CAD. LAB. XEOL. LAXE 37 (2013)

Fig. 14. Trinema sp. with cyanobacteria covering its test. Trapa, Galicia, Spain. Fig. 15 Assulina muscorum. Peña del Hierro, Huelva, Spain Fig. 16 Corythion dubium. Castelo das Furnas, Portugal. Fig. 17 Idiosomes of Corythion sp. Castelo das Furnas, Portugal

CAD. LAB. XEOL. LAXE 37 (2013) First data on testate amoebae in speleothems 47

Fig. 18 Set of Corythion dubium. Hölick Grotta, Sweden. Fig. 19 Trinema lineare. Western Australia Fig. 20 Flowstone. Las Jaras, Córdoba, Spain Fig. 21 Cylindrical speleothem. Las Jaras, Córdoba, Spain

48 González et al. CAD. LAB. XEOL. LAXE 37 (2013)

Fig. 22. Cylindrical speleothem. Skalbeberguet, Sweden. Fig. 23 Sphenoderia lenta. Porteliña, Galicia, Spain. Fig. 24. Physochila (Nebela) griseola. Porteliña, Galicia, Spain. Fig. 25 Centropyxis sp. Castelo das Furnas, Portugal

CAD. LAB. XEOL. LAXE 37 (2013) First data on testate amoebae in speleothems 49

50 González et al.

CAD. LAB. XEOL. LAXE 37 (2013)

RESULTS AND DISCUSSION

berg, 1872) (Fig. 4), Sphenoderia lenta (Schlumberger, 1845) (Fig. 23), Tracheleuglypha dentata (Moniez, 1888) (Fig. 7), Assulina muscorum (Greeff, 1888) (Fig. 15). Species of the family Trinematidae (Hoogenraad & De Groot, 1940): Trinema complanatum (Penard, 1890) (Fig. 8), Trinema enchelys (Ehrenberg, 1838) (Fig. 10), Trinema lineare (Penard, 1890) (Fig.19), Corythion dubium (Taranek, 1881) (Fig.16). Species from the Family Nebelidae (Taranek, 1882): Physochila (Nebela) griseola (Wailes & Penard, 1911) (Fig.24). Some specimens provisionally assigned to the Family Centropyxidae (Jung, 1942) (Fig.25) were identified. In the following table we can observe how the distribution of species of the analysed samples is presented:

The direct observations under the scanning electronic microscope and the later study of the obtained graphic documentation allowed us to identify the different species of the testate amoebae present. The habitual genera of testate amoebae from caves in igneous rocks correspond to Trinema, Euglypha, Corythion and Centropyxis with the distinct feature of having flattened morphologies and small size. Apparently, the genera inherent to edaphic environments, according to Lousier (1974, 1982), coincide with the ones found in our caves. The following species of testate amoebae were identified: Species from the Family Euglyphidae (Wallich, 1864): Euglypha rotunda (Wailes, 1911) (Fig. 6), Euglypha strigosa (Ehren-

1

Euglypha rotunda Wailes Euglypha strigosa Ehrenberg Sphenoderia lenta Schlumberger Tracheleuglypha dentata Moniez Assulina muscorum Greeff Trinema complanatum Penard Trinema enchelys Ehrenberg Trinema lineare Penard Corythion dubium Taranek Nebela griseola Penard

2

3

4

5

6

7

8

x x

x

x

x x x x x

x x x x

10 11 12 13 14

x x x

x

9

x x

x

x x x x

x

x x

x

x

x

x

Table 2. Distribution of species identified in the different locations geographically marked with a number: (1) Swaziland, Gobholo; (2) Austria; (3) Western Australia and South Australia; (4) Spain, Ávila; (5) Spain, Córdoba, Las Jaras; (6) Spain, Badajoz, Berrocal del Rugidero; (7) Spain, Galicia, A Trapa; (8) Spain, Galicia, Louro; (9) Spain, Galicia, Porteliña; (10) Spain, Huelva, Peña del Hierro; (11) Portugal, Castelo da Furna; (12) Sweden, Falkberget; (13) Sweden, Hölick Grotta; (14) Sweden, Tröllhallet.

CAD. LAB. XEOL. LAXE 37 (2013)

The observations made in different caves in igneous rocks (Table 2) allowed us to elaborate a quite varied inventory of species where a few are exclusive of a location. Though the work was carried out on a geographically diverse sample (with clear prevalence of samples from Spain and Sweden) (Mapa 1), a great homogeneity in the distribution of the identified amoebae species may be observed. This indicates that, in spite of the different bioclimatic conditions of the external environment of the cave, the pseudokarstic microsystem is very similar inside; thus, in our opinion, it explains the similarity of the spectrum of the identified species. It is obvious that a greater sampling should be studied, both in the number of studied speleothems and the origin zones. Some authors (AOKI et al. 2007) assign the testate amoebae a very important role in the silica cycle based on the fact that the high solubility of the amorphous (or biogenic) opal, main mineral of the test, provides a great mobility to the silica. However, considering the scarce volume of speleothems in caves in igneous rocks and the

First data on testate amoebae in speleothems 51

scarce abundance of tests that are in them, this affirmation seems to be not very plausible from the sedimentary point of view. It is convenient to take into account that most of the speleothems are formed by mineral clasts of quartz, feldspar and mica coming from the granular disaggregation of the rock due to physical weathering. The biogenic fraction (and more specifically, the amorphous opal) is reduced to a superficial film of some few micra thick that in some cases covers the whole surface of the speleothems being either cylindrical or planar, and only in cases of repeated re-dissolution gives rise to the formation of not very thick rhythmical structures. The tests will disperse over this thin film of amorphous opal (Fig. 22) but never in large concentrations of individuals. Possibly at global scale and considering the large water volumes that move in the terrestrial surface, large rates of the silica mobilization may be quantified. But at the scale of speleothems from caves in igneous rocks studied in this work, the importance of this mineral (amorphous opal) or of the silica is practically symbolic.

52 González et al.

CAD. LAB. XEOL. LAXE 37 (2013)

TEMPERATE ZONE

WARM ZONE

TEMPERATE ZONE

COLD ZONE

g h

a b

c

d

e

f

i

j

L

m

k

n

COLD ZONE

Map 1. World’s climatic zones with the main granites and granitoids areas in grey. Locations from which the samples were taken: a. Galicia - Northwestern Spain; b. Minho - Northern Portugal; c. Guadarrama Sierra - Central Spain; d. Girona- Northeastern Spain; e. Austria; f. Central Sweden; g. Anillaco, La Rioja - Argentina; h. Sierra Grande de Córdoba - Argentina; i. Gobholo, Swaziland – Southeastern Africa; j. Andringrintra Massif – Madagascar; k. Eyre Peninsula – Southern Australia – Australia; l. Hyden Rock – Western Australia – Australia; m. Devil’s Marbles – Northern Territory – Australia; n. Darwin - Northern Territory – Australia

CAD. LAB. XEOL. LAXE 37 (2013)

First data on testate amoebae in speleothems 53

CONCLUSIONS

BIBLIOGRAPHY

Testate amoebae with amorphous opal idiosomes are common microorganisms in pseudokarstic environments developed in massifs of igneous rocks. There is a great homogeneity in the spectrum of species represented that appear to have a great independency from the weather conditions existing outside the cave and also from the type of igneous rock in which they have developed. The determinant factors seem to be the following: first, the humidity (independently from the frequency and persistence of the wet period) in the caves; second, the availability of silica in the cavity. The preservation state of the tests is a reliable microenvironmental indicator of the underground environment that allows knowing the humidity grade existing therein at the time the sample was collected: well-preserved tests in humid period, bad preserved tests in dry period, tests colonized by cyanobacteria in the reestablishment of the humidity conditions in the cave.

AOKI, Y., HOSHINA, M. and MATSUBARA, T. (2007). Silica and testate amoebae in a soil under pineoak forest. Geoderma 142:29–35. ARMYNOT du CHATELET, E., GUILLOT, F., RECOURT, P., VENTALON, S. and TRIBOVILLARD, N. ( 2010). Influence of sediment grain size and mineralogy on testate amoebae test construction. Comptes Rendus - Geoscience. 342(9), 710-717. BASTIAN, F., ALABOUVETTE, C. and SAIZ-JIMENEZ, C. (2009). Bacteria and free-living amoeba in the Lascaux Cave. Res.Microbiol. 160(1), 38-40. BEINLICH, A. and AUSTRHEIM, H. (2012). In situ sequestration of atmospheric CO2 at low temperature and surface cracking of serpetinized peridotite in mine shafts. Chemical Geology, 33233, 32-44. CALDCLEUGH, A. (1829). On the geology of Rio de Janeiro. Trans.Geol.Soc. London, 2, 69-72. COPPELLOTTI, KRUPA O. and GUIDOLIN, L. (2003). Taxonomy and ecology of ciliate fauna (Protozoa, Ciliophora) from karst caves in North-East Italy. Subterr. Biol. 1: 3–11 CLARKE, K. J. (2003). Guide to the identification of soil protozoa - testate amoebae. Soil Biodiversity Programme Research Report No. 4 ed. D. W. Sutcliffe, editor. The Ferru House, Far Sawrey, Ambleside, Cumbria: CEH-Windermere in collaboration with the Freshwater Biological Association. FORTI, P. (2001). Biogenic speleothems: an overview. Int. J. Sepeleol., 30ª(1/4), 3956.

ACKNOWLEDEMENTS We must thank very much Dr. Edward A. D. Mitchell, Dr. Ralf Meisterfeld and Dr. David Wilkinson who helped out with the testate amoebae identifications and specific bibliography at our beginning. We also thank Rabbe Sjöberg, Rudolf Pavuza, Rune Magnusson, Johanes Lundberg and Darron Raw for the remittance of samples of speleothems. This work was founded with the Project PROXIES II (CGL2011-30141) of the Ministry of Economy and Competitiveness of Spain.

54 González et al.

FORTI, P. (2005). Genetic processes of cave minerals in volcanic environments. An overview. Journal of Cave and karst studies, v.67, nº1, 3-13. GARCÍA-SÁNCHEZ, A. M., ARIZA, C., UBEDA, J. M., MARTÍN-SÁNCHEZ, P. M., JURADO, V., BASTIAN, F., ALABOUVETTE, C., and SAIZJIMÉNEZ, C. (2013). Free-living amoebae in sediments from the Lascaux Cave in France. International Journal of Speleology. 42(1), 9-13. KASHIMA, N., IRIE, T. and KINOSHITA, N. (1987). Diatom contribution of coralloid speleothems, from TogawaSsakaidani-Co Cave in Miyazaki Prefecture, Central Kyushu, Japan. International Journal of Speleology, 16, 95-1200. LOUSIER, J. D. (1974). Effects of experimental soil moisture fluctuations on turnover rate of testate amoebae. Soil Biol Biochem. 6:19–26. LOUSIER, J. D. (1982). Colonization of decomposing deciduous leaf litter by Testacea (Protozoa, Rhizopoda): Species succession, abundance and biomass. Oecologia 52:381–388. MAZEI, Y., BELYAKOVA, O., TRULOVA, A., GUIDOLIN, L. and COPPELLOTTI, O. (2012). Testate amoebae communities from caves of some territories in European Russia and North-Eastern Italy. Protistology, 7: 42-50. MITCHELL, E. A. D., CHARMAN, D. J. and WARNER, B. G. (2008). Testate amoebae analysis in ecological and paleoecological studies of wetlands: past, present and future. Biodivers.Conserv. 17(9), 2115-2137. NORTHUP, D. E. and LAVOIE, K. H. (2001). Geomicrobiology of caves: a review. Geomorcrobiology Journal, 18, 199-222.

CAD. LAB. XEOL. LAXE 37 (2013)

OGDEN, C. G. and HEDLEY, R. H. (1980). An Atlas of Freshwater Testate Amoebae. Oxford: Oxford University Press. OKLAND, I., HUANG, S., DAHLE, H., THORSETH, I. H. and PEDERSEN, R. B. (2012). Chemical Geology, 318319- 75-87. RAVEN, J. A. and GIORDANO, M. (2009). Biomineralization by photosynthetic organisms: Evidence of coevolution of the organisms and their environment? Geobiology 7:140–154. SMITH, H. G., BOBROV, A. and LARA, E. (2008). Diversity and biogeography of testate amoebae. Biodivers.Conserv. 17(2), 329-343. VIDAL ROMANÍ, J. R., GRAJAL, M., VILAPLANA, J. M., RODRÍGUEZ, R., MACIAS, F., FERNÁNDEZ, S. and HERNÁNDEZ PACHECO, E. (1979). Procesos actuales: micromodelado en el granito de Monte Louro, Galicia España (Proyecto Louro). Actas IV Reunión G. E. T. C., Banyoles (España), 246-266. VIDAL ROMANÍ, J. R. (1983). El Cuaternario de la provincia de A Coruña. Geomorfología granítica. Modelos elásticos de formación de cavidades. Tesis Doctoral. Servicio de Publicaciones. Universidad Complutense, Madrid. VIDAL ROMANÍ, J. R. and VILAPLANA, J. M. (1984). Datos preliminares para el estudio de espeleotemas en cavidades graníticas. Cadernos do Laboratorio Xeolóxico de Laxe, 7: 305-324. VIDAL ROMANÍ, J. R., TWIDALE, C. R., BOURNE J. and CAMPBELL, E. M. (1998). Espeleotemas y formas constructivas en granitoides. In: Investigaciones recientes en la Geomorfología española. (Ortiz, A. G. & Franch, F. S., Eds.) 1ª edición. Barcelona: Actas Reunión de

CAD. LAB. XEOL. LAXE 37 (2013)

Geomorfología (Granada). 777-782. VIDAL ROMANÍ, J. R., BOURNE, J. A., TWIDALE, C. R. and CAMPBELL, E. M. (2003). Siliceous cylindrical speleothems in granitoids in warm semiarid and humid climates. Zeitschrift für Geomorphologie, 47(4): 417-437. VIDAL ROMANÍ, J. R. and VAQUEIRO, M. (2007). Types of granite cavities and associated speleothems: genesis and evolution. Nature Conservation 63, 41-46. VIDAL ROMANÍ, J. R., SANJURJO SÁNCHEZ, J., VAQUEIRO RODRÍGUEZ, M. and FERNÁNDEZ MOSQUERA, D. (2010 a). Speleothem development and biological activity in granite cavities. Geomorphologie. Relief, processus, environment , (4), 337- 346. VIDAL ROMANÍ, J. R., SANJURJO SÁNCHEZ, J., VAQUEIRO, M. and FERNÁNDEZ MOSQUERA, D. (2010 b). Speleothems of Granite Caves. Comunicações Geológicas, 97: 71-80. WALOCHNIK, J. and MULEC, J. (2009). Free-living amoebae in carbonate precipitating microhabitats of karst caves and a new vahlkampfiid amoeba, Allovahlkampfia spelaea gen. nov., sp. nov.

First data on testate amoebae in speleothems 55

Acta Protozool. 48(1), 25-33. WEBB, J. A. and FINLAYSON, B. L. (1984). Allophane and opal speleothems from granite caves in south-east Queensland. Australian Journal of Earth Sciences , 31, 341-349. WILKINSON, D. M. and MITCHELL, E. A. D. (2010). Testate amoebae and nutrient cycling with particular reference to soils. Geomicrobiol.J. 27(6-7), 520-533. WILKINSON, D. M. (2008). Testate amoebae and nutrient cycling: peering into the black box of soil ecology. Trends in Ecology and Evolution. 23(11), 596-599. WOO, K. S., CHOI, D.W. and LEE, K. C. (2008). Silicification of cave corals from some lava tube caves in the Jeju Island, Korea: Implications for speleogenesis and a proxy for paleoenvironmental change during the Late Quaternary. Quaternary International, 176-177, 82-95. WYLEZICH, C., MEISTERFELD, R., MEISTERFELD, S. and SCHLEGEL, M. (2002). Phylogenetic analyses of small subunit ribosomal RNA coding regions reveal a monophyletic lineage of euglyphid tesytate amoebae (order Euglyphyda). J. Eukaryot. Microbiol., 49(2), 108-118.

Cadernos Lab. Xeolóxico de Laxe Coruña. 2013. Vol. 37, pp. 57 - 64

ISSN: 0213-4497

Development trends of tafoni forms (incipient stages)

DE UÑA ÁLVAREZ, E1

(1) Area: Physical Geography. University of Vigo.Research Group (GEAAT): Archaeology, Antiquity,Territory.Campus As Lagoas – 32004 Ourense. [email protected]

Abstract Forms called tafoni, diversified in different stages, are complex natural systems. The systematic register of their measurements is performed in order to infer relative ages and to use the results to reconstruct landscape evolution. The analysis of depth measures of the cavities developed into several tafoni demonstrates, for incipient cases in Galicia (NW of Iberian Peninsula), trends with different evolutionary trajectories. Depth measures were processed with robust statistical techniques. The development of tafoni combines linear and non-linear phases. This behaviour is related to the increase of complexity through self-organisation. Key words: Tafoni; Galicia: development

58 De Uña Álvarez, E

RESEARCH FRAMEWORK Tafoni are small caves frequently developed in granitic rocks. Their interpretation has created a range of nominal categories defined by morphological and dimensional features. These forms are usually basal and lateral hollows on the undersides of blocks, boulders and sheet structures extended upwards into the rock mass (TWIDALE & BOURNE, 2008). The debate remained about the definition of the cause, either physical or chemical, and about configuration controls, their age and evolution. Tafoni show a size range from several centimetres to several metres with diverse opening plane shape (spherical, hemispherical, elliptical or irregular). The most common features of these cavities in granite terrains are cross-section in arch shape; their inner walls may be regular, flaked, honeycombed, ribbed or scalloped (TWIDALE & VIDAL, 2005). The features of morphological design and the dimensions are related to the starting control of the generative fields. This work has been developed in a sector of Galicia (NW of Iberian Peninsula). The rock basement is granite and granodiorite. The analysis is oriented towards variabil-

CAD. LAB. XEOL. LAXE 37 (2013)

ity patterns in the development of the inner walls. The systematic register of the depth of cavities into several tafoni demonstrates the behaviour of their development with different evolutionary trajectories for the cases in Galicia. This approach provided results about morphological diversity (DE UÑA, 2004; DE UÑA & VIDAL, 2008). Tendencies towards regularity or irregularity are outlined. STUDY AREA Field data were recorded for several cases developed in two locations (Fig. 1). This study only displays the results for selected cases. First sample comes from Os Castelos (20-160 m a.s.l.) in the Coruña massif and second sample comes from Vilar-Mende (180-480 m a.s.l.) in the Ourense massif. All the tafoni are active forms in development. The host rocks are not moved or split. The position of these cavities is always upon the edge of the granitic intrusion.Types were assigned according to the position of an initial discontinuity plane of growth in their host unity. Basal type defines forms developed beneath boulders or blocks. Sidewall type defines forms developed in quite sloped surfaces of rock.

Development trends of tafoni forms 59

Figure 1. Study area: location of the samples.

CAD. LAB. XEOL. LAXE 37 (2013)

60 De Uña Álvarez, E

CAD. LAB. XEOL. LAXE 37 (2013)

ANALYSIS In order to typify the growth stage of each tafoni, the selected measures are the maximum depth of each cavity inside the main hollow (Table 1). This depth measure (cm) is the value of the vertical axis inside a cavity (Fig. 2). Minimum number of the

inner cavities in the samples is three; maximum number of the inner cavities in the samples is twelve. All depth data have been processed with statistics techniques. These techniques have an instrumental value, as they discriminate between possibilities of permanence, transition or change in the tafoni development.

Table 1. Selected cases (tafoni) Type

Location

Position*

D1

IC

D2

Basal a b c

Mende Vilar Castelos

250 m 480 m 20 m

16 130 100

4 9 5

14 70 68

Side-wall a b c

Mende Mende Castelos

190 m 180 m 160 m

15 60 200

3 12 5

14 52 70

* m a.s.l. D1 = Maximum depth in basal and side-wall forms (cm). IC = Number of inner cavities. D2 = Maximum depth of the inner cavities (cm).

Research results provide the trends in the inner diversification of the tafoni throughout their development. Multiple states in continuous change are presented where growth in depth reveals cascade sequences of creation, persistence, or transformation related to critical configurations. Previous studies in this area (DE UÑA & VIDAL, 2006) prove that the opening of

the tafoni is a self-reinforcing process starting from a discontinuity plane. Their shape is usually a circle or an ellipse, with strong positive correlation between the measures of the length and the width (Spearman coefficient >0.90). However, the trends of growth in depth may be different. The statistical analysis of their values allows understanding it.

Figure 2. Depth measures from main cavity (left), inner cavities (right).

CAD. LAB. XEOL. LAXE 37 (2013)

First stage of analysis has an exploratory character. Box-plots from depth cavities in the selected tafoni (Fig. 3) reveal three possible conditions. Very incipient development (a), in basal and side-wall forms, has similar values (maximum depth 80 cm), y posiblemente se clasificaría como un Cambisol (F.A.O., 2006). Las muestras se secaron al aire y se tamizaron por 2 mm antes de su análisis. El pH se determinó en una suspensión acuosa y en KCl 0,1N (en ambos casos con una relación sólido líquido 1:2,5), según se describe en GUITIÁN & CARBALLAS (1976). Para las determinaciones de elementos totales las muestras fueron molidas en un mortero de ágata. Las concentraciones de C, N y S totales se determinaron en un analizador Elementar Vario Macro. Las concentraciones totales

CAD. LAB. XEOL. LAXE 37 (2013)

de metales pesados y As se determinaron por fluorescencia RX en un equipo Phillips PW 1404, con tubo de rayos X de Sc-Mo. RESULTADOS Y DISCUSIÓN Todas las muestras tomadas fueron ácidas o fuertemente ácidas, siendo los valores de pH más bajos para los suelos de mina que para los suelos naturales (Tabla 2). Aunque los suelos naturales llegan a presentar valores de pH en agua por encima de 5 (C4 y C5), todos los suelos (naturales y de mina) presentaron valores de pH en KCl menores de 5, llegándose en algunos casos a valores extremos por debajo de 3 (M3, M7, M8). Estos valores de pH son los esperados para suelos sobre materiales de partida ácidos bajo un clima húmedo; además, en el caso de los suelos de mina, especialmente cuando existen sulfuros, la tendencia a la acidificación es más acusada, por lo que no es raro observar valores tan bajos como los encontrados aquí.

CAD. LAB. XEOL. LAXE 37 (2013)

Suelos naturales

Suelos de mina

Precipitados

The Valborraz tungsten mine: Description of 155

pHw

pHKCl

C total (%)

N total (%)

C/N

S total (%)

C1

4,8

3,8

5,7

0,42

14

0,05

C2

4,3

3,6

10,6

0,75

14

0,06

C3

4,9

3,9

8,4

0,50

17

0,04

C4A

5,0

3,9

2,4

0,26

9

0,02

C4C

5,4

4,4

1,3

0,20

6

0,04

C5A

5,8

4,8

3,3

0,30

11

0,04

C5Bw

5,4

3,9

0,4

0,09

5

0,02

C5C1

5,4

3,9

0,3

0,08

3

0,02

M1A

4,0

3,3

2,9

0,18

16

0,41

M1C

3,8

3,4

0,61

0,08

8

0,45

M2

5,2

3,9

6,0

0,41

15

0,06

M3

3,5

2,8

0,25

0,05

5

0,78

M4

3,9

3,5

0,23

0,07

4

0,21

M5

3,9

3,9

6,0

0,42

14

0,42

M6

3,8

3,6

0,39

0,05

8

0,44

M7A

3,1

3,0

0,61

0,07

9

0,59

M7C

3,0

2,9

0,52

0,06

9

0,53

M8

3,3

2,9

5,1

0,29

18

0,36

M9

4,6

4,2

0,21

0,04

6

0,20

O

3,9

3,9

2,59

0,20

13

0,90

Tabla 2. Propiedades generales de los suelos.

Las concentraciones de carbono y nitrógeno totales, que indican el contenido en materia orgánica de los suelos, oscilaron notablemente entre muestras, siendo mayores en los horizontes superficiales que en los subsuperficiales, como es lógico. En general, los suelos naturales presentaron concentraciones mayores de C y N que los suelos de mina, aunque hay que destacar que en algunos de estos últimos las concentraciones fueron muy elevados (M1, M2, M5, M8).

Todos los suelos de mina están enriquecidos en azufre con respecto a los naturales, se hallen estos dentro o fuera del recinto de la mina, indicando así la presencia de mayores cantidades de sulfuros en los residuos mineros que en los materiales de partida de los suelos naturales. El contenido de azufre es muy bajo en estos (inferior al 0,06%), mientras que es significativamente mayor en los suelos de mina (entre 0,06 y 0,60%, con un 0,90% como valor máximo en el precipitado de óxidos de hierro). La

156 Cárdenes et al.

presencia de sulfuros en los materiales de partida es seguramente la fuente de acidez de los suelos, puesto que se ha encontrado una elevada correlación negativa entre el contenido de azufre y el pH en agua (r = -0.90**). Este elemento también está relacionado con la presencia de As, como se verá (Figura 5). La Tabla 3 muestra las concentraciones totales de Fe, metales pesados y As en las muestras. Los suelos situados en la mina presentan concentraciones de Fe (8,2-23,6%) mayores que las de los suelos situados fuera de la misma (3,2-6,7%), lo que indica que el material de partida es más rico en hierro en la zona de la mina. Las concentraciones de Zn no fueron particularmente altas, y en todo caso los suelos de la mina estuvieron en el mismo

CAD. LAB. XEOL. LAXE 37 (2013)

rango que los suelos fuera de la mina. Las concentraciones de Cu y Ni fueron muy variables dentro de los diferentes suelos de mina, aunque en general se observó que los suelos dentro de la mina tienen concentraciones ligeramente mayores que los suelos control. Las concentraciones de estos tres elementos se encontraron por debajo de los valores considerados fitotóxicos (KABATA-PENDIAS & PENDIAS, 1984), con las excepciones del Ni en el suelo M1, y Cu en los suelos M1 y M3. Globalmente, las concentraciones de Cu, Ni y Zn en los suelos de la mina pueden considerarse moderadas, especialmente teniendo en cuenta que las zonas afectadas por minería metálica pueden presentar valores mucho más elevados para estos elementos (JOHNSON et al., 1995).

CAD. LAB. XEOL. LAXE 37 (2013)

Suelos naturales

Suelos de mina

Precipitados Fitotoxicidad

The Valborraz tungsten mine: Description of 157

Fe (%)

Ni (mg kg-1)

Cu (mg kg-1)

Zn (mg kg-1)

As (mg kg-1)

C1

12,4

34

61

74

3423

C2

10,4

64

95

144

2212

C3

8,5

18

38

62

1210

C4A

6,7

53

48

86

45

C4C

6,2

20

33

94

29

C5A

3,2

19

37

53

104

C5Bw

3,4

23

22

56

72

C5C1

4,0

31

22

70

65

M1A

17,3

128

130

85

10318

M1C

18,0

109

9

43

14419

M2

9,9

66

16

104

4954

M3

21,4

39

295

59

1101

M4

9,6

31

5

64

5926

M5

23,6

108

88

32

14475

M6

8,8

nc

nc

53

5669

M7A

10,0

54

28

53

8243

M7C

9,8

34

10

49

10045

M8

9,3

nc

nc

nc

13460

M9

8,2

40

50

106

5713

O

31,5

nc

nc

nc

39578

-

100

125

400

20-50

Tabla 3. Composición total de las muestras, y umbrales de toxicidad en suelo según Kabata-Pendias y Pendias (1984).

Las concentraciones de As de los suelos dentro de la mina (sean naturales o desarrollado sobre residuos) son mucho mayores que la de los suelos control (C4 y C5), que ya de por sí son bastante elevadas para lo común en suelos naturales, que no suelen presentar concentraciones superiores a 10 mg kg-1 (ADRIANO, 2001). Estas

elevadas concentraciones de As en suelos naturales presumiblemente no contaminados se pueden explicar teniendo en cuenta que el fondo geoquímico para la región es de unos 20 mg kg-1 (GUITIÁN OJEA, 1992), y que los suelos tienden a incrementar sus concentraciones de As con respecto al material de partida. Así, los suelos naturales

158 Cárdenes et al.

desarrollados sobre pizarras en la región pueden llegar a presentar concentraciones de arsénico por encima de 150 mg kg-1 (MACÍAS & CALVO, 2008), por lo que los valores de los suelos C4 y C5, entre 29 y 104 mg kg-1, aún siendo elevados, entran dentro de lo esperado. Sin embargo, esto no puede explicar las altísimas concentraciones de As de los suelos dentro de la mina, no encontrándose ningún valor por debajo de 1000 mg kg-1, y superándose en muchos casos los 10000 mg kg-1. Los tres suelos naturales (C1 a C3) presentan concentraciones en el rango 12103423 mg kg-1, con un valor medio de 2282 mg kg-1, mientras que los suelos de mina (M1-M9) presentan valores mayores, entre

CAD. LAB. XEOL. LAXE 37 (2013)

5669-14475 mg kg-1, con un valor medio de 8575 mg kg-1. La mayor concentración corresponde a los precipitados de óxidos de hierro, que alcanzan un valor de casi 40000 mg kg-1. Estos valores son tan altos que no puede dudarse de que su origen no es natural, sino antropogénico y ligado a las actividades mineras en la zona, y parece también claro que los suelos naturales (C1C3) han debido ser contaminados de algún modo por causa de la propia actividad. Se ha encontrado también una correlación positiva entre la concentración de arsénico y el porcentaje de azufre (r=0.84**), de modo que se puede decir que la presencia del arsénico en estas muestras está ligada a sulfuros como la arsenopirita.

CAD. LAB. XEOL. LAXE 37 (2013)

The Valborraz tungsten mine: Description of 159

Figura 5. Variación del pH y la concentración de As con la concentración de S.

Desde el punto de vista toxicológico, si el valor del LC50 en humanos se establece en 1 mg kg-1, y teniendo en cuenta que muchos de los suelos dentro de la mina presentaron concentraciones de arsénico entre 1000 y 10000 mg kg-1, podemos calcular que la cantidad de suelo contaminado que sería necesario ingerir para alcanzar este umbral en un adulto de 70 kg oscilaría entre 7 y 70 gramos, mientras que para un niño de 25 kg serían entre 2,5 y 25 gramos. Aunque es improbable que un humano pueda consumir estas cantidades de suelo, hay que recordar que el LC50 indica la dosis letal para el 50% de una población, por lo que el riesgo asociado a esta zona es notablemente alto.

En la actualidad se están realizando estudios sobre las formas químicas en las que se encuentra el As en los suelos de la mina, así como sobre su movilidad y disponibilidad potencial para las plantas. Se maneja como hipótesis que el abundante hierro de las rocas de la zona, precipitado en grandes cantidades en las zonas mal drenadas de la zona, podría jugar un papel importante en la movilidad del As. Varios autores han destacado ya la baja movilidad del As debido a la baja solubilidad de la escorodita en las escombreras y la elevada capacidad de los oxihidróxidos de hierro para la adsorción de As (RICHMOND et al., 2004; GARCÍA-SANCHEZ et al.,

160 Cárdenes et al.

2010), y en esta dirección apunta el hecho de que las mayores concentraciones de As total hayan sido encontradas en los precipitados de óxidos de hierro. CONCLUSIONES Los suelos de las minas de Valborraz presentan concentraciones anormalmente altas de arsénico, originadas como consecuencia de la minería del tungsteno que se desarrolló principalmente durante la primera mitad del siglo XX. Aunque hasta el momento no se han encontrado indicios de que esto haya dado lugar a un caso de contaminación del agua, las elevadas concentraciones de As hacen de la zona un área potencialmente peligrosa. Estas grandes cantidades de As en los suelos deben estar principalmente en formas no solubles o de escasa movilidad, puesto que hasta ahora no se ha detectado contaminación por arsénico en las aguas de la zona, a pesar de que el área de la mina es atravesada por torrentes de montaña. La elevadísima concentración de As encontrada en los óxidos de hierro precipitados en una de las zonas de encharcamiento sugiere un papel protagonista de este elemento en la inmovilización del As, que podría ser retirado de la disolución bien por coprecipitación o bien por adsorción sobre los óxidos de hierro. Sin embargo, y aunque se demostrase que el As aparece en formas poco móviles en las condiciones actuales, hay que tener en cuenta que cualquier modificación en las condiciones físicas o químicas del área contaminada puede dar lugar a cambios en la especiación y movilidad de este elemento, con efectos potencialmente negativos sobre el medio ambiente y la salud humana.

CAD. LAB. XEOL. LAXE 37 (2013)

REFERENCIAS ADRIANO, D. C. (2001). Trace elements in terrestrial environments. Biogeochemistry, bioavailability and risk of metals. Springer, New York. BODEGA, F. (1982). Resultados de la investigación en el Grupo “Tres Amigos”, Casayo (Orense). Cadernos do Laboratorio Xeolóxico de Laxe, 6, 441458. BOYLE, R. W. and JONASSON, I. R. (1973). The geochemistry of arsenic and its use as an indicator element in geochemical prospecting. Journal of Geochemical Exploration, 2, 251-296. CÁRDENES, V., DE LA HORRA, R., MONTERROSO, C., GARCÍAGUINEA, J. and PAIS, V. (2008). Depósitos de pizarras para cubiertas en la Península Ibérica. En: Resúmenes VII Congreso Geológico de España. Sociedad Geológica de España, Las Palmas de Gran Canaria. MARTÍNEZ CORTIZAS, A. and PÉREZ ALBERTI, A. (1999). Atlas climático de Galicia. Xunta de Galicia, Santiago de Compostela. DANI, S. U. (2010). Arsenic for the fool: An exponential connection. Science of the Total Environment, 408, 1842–1846. F.A.O. (2006). World Reference Base for Soil Resources 2006. Food and Agriculture Organization of the United Nations, Rome. GARCÍA-GUINEA, J., LOMBARDERO, M., ROBERTS, B. and TABOADA, J. (1997). Spanish Roofing Slate Deposits. Transactions of the Institute of Mineral Metallurgy, Section B, 106, 205-214. GARCÍA-SÁNCHEZ, A., ALONSOROJO, P. and SANTOS-FRANCÉS,

CAD. LAB. XEOL. LAXE 37 (2013)

F. (2010). Distribution and mobility of arsenic in soils of a mining area (Western Spain). Science of the Total Environment, 408, 4194-4201. GARCÍA TATO, I. (1996). Valdeorras de cara al año 2000. Instituto de Estudios Valdeorreses, Ourense. GUITIÁN OJEA, F. (ed.) (1992). Atlas geoquímico de Galicia. Xunta de Galicia, Santiago de Compostela. GUITIÁN, F. and CARBALLAS, T. (1976). Técnicas de análisis de suelos. Ed. Pico Sacro, Santiago de Compostela. GURRIARÁN, R. (2000). Da prerromanización ao wolfram: Apuntamentos históricos das explotacións mineiras en Valdeorras. Instituto de Estudios Valdeorreses, Ourense. HURLBUT, C. S. and KLEIN, C. (1985). Manual of Mineralogy. 20th ed. John Wiley and Sons, New York. I.A.R.C. (1982). Monographs on the Evaluation of the Carcinogenic Risk of Chemicals to Humans, vol. 23, Some Metals and Metallic Compounds. IARC, Lyon. JOHNSON, M. S., COOKE, S. A. and STEVENSON, J. K. (1994). Revegetation of metalliferous wastes and land after metal mining. En: Hester, R. E., Harrison, R. M. (Eds.), Mining and its environmental impact. Royal Society of Chemistry, Cambridge, pp. 31-48. JULIVERT, M., MARCOS, A. and TRUYOLS, J. (1972). L´évolution paléogéographique du Nord-Ouest de l´Espagne pendant l´Ordovicien-Silurien. Bulletin de la Societé Géologique de Bretagne, 4, 1-7. JUNG, M. C. and THORNTON, I. (1994). Heavy metal contamination in soils and plants around a copper-tungsten

The Valborraz tungsten mine: Description of 161

mine in South Korea. Environmental Geochemistry and Health, 16, 92. KABATA-PENDIAS, A. and PENDIAS, H. (1984). Trace elements in soils and plants. CRC Press, Boca Raton. LIDE, D. R. (1996). CRC Handbook of Chemistry and Physics. 77th ed. CRC Press, Boca Raton. LIU, C., LUO, C., GAO, Y., LI, F., LIN, L., WU, C. and LI, X. (2010). Arsenic contamination and potential health risk implications at an abandoned tungsten mine, southern China. Environmental Pollution, 158, 820-826. MACÍAS, F. and CALVO, R., 2008. Niveles genéricos de referencia de metales pesados y otros elementos traza en suelos de Galicia. Consellería de Medio Ambiente e Desenvolvemento Sostible, Xunta de Galicia, Santiago de Compostela, 229 pp. MARCOS, A. (1973). Las series del Paleozoico inferior y la estructura herciniana del occidente de Asturias (NW de España). Trabajos de Geología, 6, 1-113. ÖZCAN, A. and ÇAĞATAY, M. N. (1988). Tungsten exploration in semiarid environment: Central Anatolian massif, Turkey. Journal of Geochemical Exploration, 31, 185-199. PÉREZ-ESTAÚN, A. (1978). Estratigrafía y estructura de la rama S de la Zona Asturoccidental-Leonesa. Memorias del Instituto Geológico y Minero de España, 92, 1-151. RICHMOND, W. R., LOAN, M., MORTON, J. & PARKINSON, G. M. (2004). Arsenic removal from aqueous solution via ferrihydrite crystallization control. Environmental Science and Technology, 38, 2368-2372.

162 Cárdenes et al.

SMEDLEY, P. L. and KINNIBURGH, D. G. (2005). Arsenic in groundwater and the environment. En: O. Selenius (Ed.), Essentials of Medical Geology: Impacts of the Natural Environment on Public Health. Elsevier, Amsterdam, pp. 263-299.

CAD. LAB. XEOL. LAXE 37 (2013)

TERRÓN MENDAÑA, T. (1989). El estraperlo del wólfram en las minas de Casaio. Instituto de Estudios Valdeorreses, Ourense. VAUGHAN, D. J. (2006). Arsenic. Elements, 2, 71-75.

Cadernos Lab. Xeolóxico de Laxe Coruña. 2013. Vol. 37, pp. 163 - 180

ISSN: 0213-4497

Catastrophes versus events in the geologic past: how does the scale matter?

GUTAK, J. M.1 and RUBAN, D. A.2,3*

(1) Department of Physical Geography and Geology, Kuzbass State Pedagogical Academy, Kuznetsov Street 6, Novokuznetsk, Kemerovo Region, 654041, Russian Federation; [email protected], GutakJaroslav@ yandex.ru (2) Division of Mineralogy and Petrography, Geology and Geography Faculty, Southern Federal University, Zorge Street 40, Rostov-na-Donu, 344090, Russian Federation; (3) contact address: P.O. Box 7333, Rostov-na-Donu, 344056, Russian Federation; [email protected], [email protected] *corresponding author

Abstract Catastrophes were common in the geologic past, but their distinction from other events is necessary. Besides magnitude (strength), scales of events are important in a solution of this task. Several examples, which involve Late Paleozoic and Quaternary megafloods, Hadean and Phanerozoic extraterrestrial impacts, and Phanerozoic mass extinctions, ensure that scaling by spatial extent and diversity of consequences facilitates tracing the boundary between catastrophes and “ordinary” events. This boundary, however, is dynamic and its position depends on our subjective needs. Considerations of the geologic past should not mix catastrophes of different scales. The event analysis helps to avoid such a pitfall, and, therefore, it should be preferred to neocatastrophism in modern geoscience. Key words: Catastrophe; event; megaflood; extraterrestrial impact; mass extinction.

164 Gutak et al.

Introduction The Hawaiian creation chant entitled Kumulipo gives a spectacular example of how ancient Polynesians perceived a mix of gradual and sudden events in the development of nature (Beekwith, 1981). Surprisingly, modern geoscientists are faced with the same challenge, namely a clear distinction between catastrophes and other (“ordinary”) events. Much has been said about past geologic catastrophes and the rise of neocatastrophism (e.g., Dury, 1980; Berggren & van Couvering, 1984; Karrow, 1989; Hickey, 1992; Schönlaub, 1996; Hallam, 2005; Babin, 2007; Marriner et al., 2010). Babin (2007) has demonstrated recently that event analysis is a desired perspective for modern geoscience. Some classifications of geologic events exist (e.g., Ruban, 2006), but an appropriate distinction of catastrophes from other events is yet to be achieved. This problem appears to be highly complex, and it requires a multi-dimensional solution. An objective of the present essay is consideration of some catastrophes discussed in modern geoscience literature in order to demonstrate that their scale was not less important than their magnitude (their distinction is explained below). This can apparently help to create a basis for further distinction of catastrophes from “ordinary” events in the geologic past. Brief theoretical outline The geologic event is nothing more than an occurring (or already occurred) change (Ruban, 2006). Although modern geoscience often focuses on extraordinary events (e.g., Boggs, 2006; Rey & Galeotti, 2008), which are, in particular, meaningful

CAD. LAB. XEOL. LAXE 37 (2013)

for stratigraphical correlation purposes, these constitute only a small part of all events that occurred in the geologic past and were either preserved or not in the available geologic record. Catastrophes are, undoubtedly, events, but only a few events are catastrophes. So, how are the latter to be specified? Avoiding an in-depth analysis of the large amount of relevant literature (e.g., Milne, 2000; Posner, 2004; Bostrom & Ćirković, 2008), it is simple to state that catastrophes are distinguished as a large-scale process with dramatic consequences. Catastrophes are often (but likely not-necessarily) sudden, selfaccelerating, and highly-complex events. The main characteristic of a catastrophe is its magnitude, i.e., strength. E.g., 95% of life went extinct at a time of the Permian/Triassic mass extinction (Erwin, 2006). This suggests an outstanding magnitude. Global warming by 60C is forecasted to happen during the next decades according to one of the proposed scenarios (Houghton, 2009). This also indicates a magnitude of this potential catastrophe. Taking into account magnitudes of geologic events, one can rank them within the same class and with the same units. E.g., the percentage of species went extinct can help to rank biotic crises. A comparison of events belonging to different classes is a more difficult task (because of different units), which will be possible only on the basis of certain subjective judgements. But if even this is possible, it is definitely not enough to make a distinction from “ordinary” events. The geologic environment is very complex. It has physical dimensions (area and depth), complexity (various geologic bodies and processes), and dynamics (duration, abruptness, and frequency). Thus, one needs to measure the scale of past events, and, consequently,

CAD. LAB. XEOL. LAXE 37 (2013)

Catastrophes versus events in the geologic past 165

to consider their spatial extent, diversity of consequences, and temporal expression.

in this paper in order to illustrate the scaling of catastrophes in the geologic past. These include megafloods, mass extinctions, and extraterrestrial impacts. In all cases, representative examples are considered. They are taken from different time slices of geologic time (Fig. 1).

Examples Three particular subjects reflected in modern geoscience literature are mentioned

Fig. 1. Catastrophic events considered in the present essay. The geologic time scale is after OGG et al. (2008).

166 Gutak et al.

Megafloods: scaling by spatial extent Several megafloods are known from geologic history. One of them is the so-called Missoula Floods. During the Pleistocene, Lake Missoula occupied a large territory in the northwestern part of the USA (chiefly Washington and Oregon). Periodic ruptures of the ice dam, established by a tongue of the Cordilleran Ice Sheet, produced major floods (see reviews in Bretz, 1969; Anderson & Anderson, 2010; see also Appendix) also termed jökulhlaups (van Loon, 2009; Anderson & Anderson, 2010). It is reasonable to note that the differences between such megafloods from glacial lake outburst floods are rather artificial (Bennett & Glasser, 2009). Now, up to 90 floods linked with the Missoula lake are reported from the time interval of 18–15 ka, although there is evidence that similar floods occurred through the entire Pleistocene (O’Connor & Baker, 1992; Benito & O’Connor, 2003; Clague et al., 2003 Pluhar et al., 2006; Anderson & Anderson, 2010; Medley & Burns, 2010). Medley & Burns (2010) traced the history of these floods back to 780 ka at least. Lake Missoula was up to 200 m deep, and its volume was about 2700 km3, which allowed peak discharges of 13000000 m3/s and the duration of one flood during about a week (Anderson & Anderson, 2010). Each event devastated a very large area and re-shaped the landscape now termed channeled scabland. The Missoula Floods, however, were catastrophic for only the northwestern part of the USA (and, probably, neighbouring parts of Canada). They may be, probably, recognized as such on a continental, but not global scale. The other famous megaflood, sometimes called Noah’s Flood, occurred in the

CAD. LAB. XEOL. LAXE 37 (2013)

Black Sea Region. It is assumed that the Black Sea with its relatively low level (150 m below present) was isolated from the Marmara Sea and the Mediterranean at the beginning of the Holocene; sudden opening of the Bosporus Gateway at ~ 8.5–7 ka allowed a rapid water discharge with a consequent drowning of the Black Sea shelves and quick retreat of the shoreline (Ryan & Pitman, 1999; Ryan et al., 2003; Yanko-Hombach et al., 2007; Lericolais et al., 2009; Anderson & Anderson, 2010). In the worst case, the sea-level rose by ~0.5 m/day with horizontal shifts of the shoreline by ~1 km/ day (Anderson & Anderson, 2010). Despite strong geological argumentation, this scenario faces some criticism (Görür et al., 2001; Aksu et al., 2002; YankoHombach et al., 2007). If the Black Sea Flood was true, it was a catastrophe with consequences for earlier human cultures developed along the coasts of the preexisting lake (Ryan & Pitman, 1999). Indeed, the whole ecosystem of the Black Sea and neighbouring territories changed dramatically. There might have been some consequences for the Marmara Sea (and, less probably, for the Mediterranean Sea) as well as for the water exchange between the Black Sea and the Caspian Sea. However, it is unlikely that this dramatic event was a catastrophe on the global scale. Some megafloods are reported from Southern Siberia. In the Middle Frasnian (Late Devonian), there was a voluminous discharge of fresh water from the large Kohai Lake that took place in the Minusa Depression to the marine basin, which embraced the Kuznetsk Basin (Gutak & Antonova, 2006a,b). This became possible after breakup of a natural barrier somewhere in the Kuznetsk Alatau. Together

CAD. LAB. XEOL. LAXE 37 (2013)

Catastrophes versus events in the geologic past 167

with water, a lot of clastic sediment was delivered. The relevant red-coloured deposits are preserved as a clinoform with structures typical for diluvial (i.e., formed as a result of flood) beds. A sudden megaflood occurred in the same Kuznetsk Basin in the Permian (Gutak, 2008). The thickness of the relevant diluvial deposits is up to 17 m. They bear large cordaite stems (Photo 1). This megaflood event was also linked with water discharge from a lake in the Minusa Depression. It appears that rapid burial of organic matter with voluminous clastic material delivered by megafloods in the Kuznetsk Basin facilitated formation of coals (Gutak, 2008). Megafloods from glacial-dammed lakes are also reported from the Late Pleistocene of the Altay (Butvilovkij, 1993; Grosvald, 1999; Rudoy, 2002; Gutak et al., 2008). The largest Tchuja Lake was up to 140 x 70 km in size with depth up to 300 m (Gutak

et al., 2008). Destruction of ice dams resulted in cataclysmic outflow of lake waters, which occurred within some days. Peak water discharges in the Altay reached 18000000 m3/s (Rudoy, 2002). Specific landforms like giant ripples (Photo 2) and flood terraces (Photo 3) were created by these floods. The whole landscape became a scabland (Rudoy, 2002) similar to that described in North America (see above). Interestingly, megafloods took place in the Altay until the mid-Holocene (Rudoy, 2002; Gutak et al., 2008), which permits one to hypothesize that not only the landscape, but also prehistoric human societies were affected by these events. In all three cases, water discharges were, undoubtedly, catastrophic and perturbed the local palaeoenvironments and sedimentation regime. However, these catastrophes are recognizable only on the regional scale limited by the territory of Southern Siberia.

Photo. 1. Permian diluvial bed with a cordaite stem (~ 7 m in length) in the Kuznetsk Basin. I. DULIĆ stays for scale. Photo by JA.M.G.

168 Gutak et al.

CAD. LAB. XEOL. LAXE 37 (2013)

Photo 2. Giant ripples of ancient megaflood in the Altay. The height of ripples is up to 20 m. Photo by JA.M.G

Photo 3. Megaflood terrace in the Altay. The entire terrace was formed as a result of single flood episode. Photo by JA.M.G.

CAD. LAB. XEOL. LAXE 37 (2013)

Catastrophes versus events in the geologic past 169

All above-mentioned megafloods were, undoubtedly, natural catastrophes. Their direct actions and consequences were restricted to particular regions even if large. On a larger scale, they were just peculiar geologic events. There is, however, an example of megaflood with global-scale consequences. This was a cataclysmic discharge of fresh water (6 x 100 m3/s) from the proglacial Lakes Agassiz and Ojibway to the Atlantic Ocean, which perturbed major circulation patterns, produced the short-term cooling at ~8.2 ka, and induced the global sea-level change (Clarke et al., 2004; Kendall et al., 2008; LeGrande, 2009; Anderson & Anderson, 2010). It was earlier hypothesized that outflow from the same Lake Agassiz might have been responsible for the Younger Dryas event, but this idea is now under critical examination (Teller et al., 2005; Broecker et al., 2010).

the Cretaceous/Paleogene boundary and produced global wildfires, giant tsunami waves, climate perturbations, and the wellknown mass extinction (Alvarez, 2008; Schulte et al., 2010). This scenario generated various criticisms. Some authors propose another cause (e.g., volcanism) of the environmental catastrophe (Courtillot, 2007), others suggest another impact event (Keller, 2008), some provide an evidence that the hypothesized impact was not so destructive (Belcher et al., 2004, 2005), and some still question an idea of sudden mass extinction (Stow, 2010). Anyway, the above-mentioned scenario provides an example of global-scale environmental perturbation, which altered all levels of the biosphere and atmosphere and had such exceptional outcomes like 100 m-tsunami waves and planetary-persisting wildfires (Wolbach et al., 1990; Vajda et al., 2001; Dypvik & Jansa, 2003; Alvarez, 2008). Even if some dinosaurs and ammonites passed the Cretaceous/Paleogene boundary (Fassett et al., 2002; Machalski & Heinberg, 2005; Fassett, 2009; Machalski et al., 2009; Rovelli et al., 2010), these were “Dead Clades Walking” in terms of Jablonski (2004). In other words, this was a catastrophe with the highest possible diversity of consequences for the Earth’s geologic evolution. Another extraterrestrial impact has been recently hypothesized to happen at the end-Pleistocene (Firestone et al., 2007; Kennett et al., 2009). This idea faces strong criticism (e.g., Surovell & Holliday, 2009; Broecker et al., 2010; see also Appendix), but the relevant disputes are not yet ended. If this ~12.9 ka event occurred, it was a catastrophe, which provoked megafaunal extinctions and interruption of early human cultures in North America; moreover,

Extraterrestrial impacts: scaling by diversity of consequences Extraterrestrial impacts are not uncommon in the geologic past (Abbott & Isley, 2002; Napier, 2008). Some of them were extraordinary with respect to diversity of consequences. The most spectacular were those events that occurred in the very early history of the Earth. Collisions with large (with a size up to that of Mars) extraterrestrial bodies were able to melt significant portions of the crust, to remix the core and mantle, to strip the atmosphere, and to re-homogenize the entire planet; it remains under discussion how many such catastrophes occurred before 4.45 Ga and which of them was responsible for creation of the Moon (Zhang, 2005). An extraterrestrial body with the size of about 10 km collided with the Earth at

170 Gutak et al.

CAD. LAB. XEOL. LAXE 37 (2013)

this impact might have been responsible for the Younger Dryas global cooling (Firestone et al., 2007; Kennett et al., 2009). Thus, despite its lesser magnitude, the endPleistocene catastrophe (of course, if further proved) seems to be comparable by diversity of its consequences with what happened at the Cretaceous/Paleogene boundary. The Odessa hypervelocity impact occurred in the Pleistocene on the southern High Plains of North America; it devastated local ecosystems, although this effect was limited to a radius of 2 km (Holliday et al., 2005). This event likely did not trigger any significant changes in climate or biosphere. The Eltanin impact took place in the South Pacific at ~ 2.15 Ma, when a large (up to 4 km in size) extraterrestrial body collided with the Earth (Ward & Asphaug, 2002). Although it altered the bottom sediments and produced a giant tsunami wave (Flores et al., 2002; Ward & Asphaug, 2002), this impact apparently did not affect the Earth’s climate or biosphere (Flores et al., 2002). Were these two events catastrophes with respect to diversity of their consequences? If we consider only the sequence of the Earth’s collisions with other bodies, each event constituting this sequence should be judged catastrophic. In contrast, when one addresses the geologic evolution with its entire complexity, the Odessa and Eltanin impacts were close to “ordinary” events. Mass extinctions: expression A in the 1982; lam

scaling

by

temporal

series of mass extinctions occurred geologic past (Raup & Sepkoski, Sepkoski & Raup, 1986; Hal& Wignall, 1997; Hallam,

2005; Bambach, 2006; Racki, 2009). Five of them (end-Ordovician, Frasnian/ Famennian, Permian/Triassic, end-Triassic, and Cretaceous/Paleogene) are considered major, and they are often called the Big Five. Scaling of mass extinctions by their temporal expression is difficult even if possible. Both duration and abruptness are excluded as significant parameters. On one hand, there are certain pitfalls in their evaluation (e.g., van Loon, 1999). On the other hand, consideration of neither duration nor abruptness facilitates a distinction of catastrophes from “ordinary” events. E.g., the end-Ordovician mass extinction linked with a glaciation (Munnecke et al., 2010) was apparently longer and less abrupt than the asteroid-triggered Cretaceous/Paleogene mass extinction (Alvarez, 2008; Schulte et al., 2010). However, both were recognizable biotic catastrophes. Consideration of frequency poses a more complicated task. One may assume that higher frequency of events means they were “ordinary” in the geologic past. If so, major mass extinctions (the Big Five) were catastrophes, whereas minor mass extinctions (all others except for Big Five), significantly more frequent, were not. Alternatively, minor mass extinctions were “lesser” catastrophes. A distinction of major and minor mass extinctions, however, seems to be outdated. On one hand, it has been realized that some “minor” biotic collapses were comparable in their magnitude with those “major” (e.g., Ruban & Tyszka, 2005). On the other hand, even such dramatic mass extinctions like that Permian/Triassic (Erwin, 2006) were not so all-embacing. E.g., Xiong & Wang (2011) reported a rather gradual floristic turnover across the Permian–Triassic transition, but not mass extinc-

CAD. LAB. XEOL. LAXE 37 (2013)

Catastrophes versus events in the geologic past 171

tion. When Luo et al. (2008) recognized the so-called Lilliput Effect among conodonts at a time of mass extinction, Chunikhin (2008) documented an opposite pattern (i.e., increase in body size) among conchostracans. Moreover, some new significant biotic crises have been recognized. An example is the Early Silurian crisis, although its nature remains debated (Ruban, 2008; Lehnert et al., 2010). Consequently, all mass extinctions known from the geologic past should be considered together as events of the same sequence. This conclusion implies that the frequency of mass extinctions in the geologic past was high. There were no periods without mass extinctions, and in some periods like the Devonian or the Permian, life on the Earth experienced a series of such perturbations. Following the assumption given above, such high frequency indicates that mass extinctions were not catastrophes, which is evidently wrong. Increasing the resolution of our analysis, we can see that the Permian provides a fascinating example. The first mass extinction of this period was mid-Capitanian in age (Bond et al., 2010a,b). Further studies are necessary in order to understand whether it predated the earlier-hypothesized end-Guadalupian mass extinction (e.g., Stanley & Yang, 1994; Hallam & Wignall, 1997) or the latter should be re-considered as the midCapitanian (additionally, Clapham et al. (2009) suggested rejecting any Permian biotic catastrophe until the Permian/Triassic). And the next mass extinction took place already at the Permian/Triassic boundary (Erwin, 2006). Such a concentration of events within the time interval of just ~10 Ma does not disprove their catastrophic nature. The frequency of events does not matter for a distinction of catastrophes from the

“ordinary” events as well as the whole temporal expression of events. Geologic history can consist of a chain of “ordinary” events, a chain of catastrophes, or a chain of “ordinary” events superimposed by catastrophes. Discussion The examples presented above suggest that catastrophes can be distinguished from other events in the geologic past by their spatial extent and diversity of consequences. In other words, two-dimensional scaling does matter. It appears to be a sufficient supplement to the ranking of events by their magnitude. But where is the boundary between catastrophes and “ordinary events” according to the scaling? Focusing on smaller areas and only particular aspects of the geologic history increases the importance of some events and makes them catastrophes. This means the noted boundary is dynamic, depending on our needs, and, consequently, it is rather subjective. Both Missoula (and analogous megafloods in Southern Siberia) and Agassiz– Ojibway megafloods were catastrophes as well as the Chicxulub and Eltanin extraterrestrial impacts. But these pairs do not include catastrophes of comparable scales (Fig. 2). It appears that the geologic history of the Earth should include only global-scale and highly-comprehensive catastrophes. Regional-scale and less-comprehensive (i.e., lessdiverse) events, if even such outstanding as the Noah’s Flood or the Odessa impact, were “ordinary” from the planetary point of view. This means that sequences of events should be established separately for the Earth and the particular regions as well as for the selected aspects of the planetary evolution and this evolution taken in the whole. Any mix of these sequences should be avoided.

172 Gutak et al.

CAD. LAB. XEOL. LAXE 37 (2013)

Fig. 2. Conceptual scaling of megafloods (black: 1 - Missoula, 2 - Altay, 3 - Agassiz-Ojibway) and extraterrestrial impacts (grey: 4 - Eltanin, 5 - Chicxulub). Distinction between catastrophes and “ordinary” events can be made provisionally depending of subjective needs and preferences (few possible examples of such a distinction are shown by dashed lines).

The consideration presented just above is a very important premise for broad implications of the event analysis in modern geoscience. This analysis focuses on a recognition and distinction of events and establishes their characteristics later. The event analysis is not biased by consideration of the only somewhat exceptional (Ruban, 2006). This technique allows multi-level and dynamic distinction between catastrophes and other events, which is inevitable as suggested by examples presented in this essay. If so, modern geoscientists should not only favour event analysis, but make its clear distinction from approachs of neocatastrophism (the latter is a general term for concepts, which treat catastrophes as the main events in the geologic history or even as the driving force of the Earth’s development). Similarly-sounded suggestion by Babin (2007) is, therefore, not an appeal, but valuable instruction.

Conclusions Examples of megafloods, extraterrestrial impacts, and mass extinctions known from geologic history demonstrate that not only magnitude, but also scale is important for a clear distinction of catastrophes from “ordinary” events. Two-dimensional scaling, which involves spatial extent and diversity of consequences, is implied in order to establish the nature of events. However, recognition of catastrophes is rather a subjective procedure, which depends heavily on our needs. The boundary between catastrophes and “ordinary” events is subjective. When the geologic past is discussed, it should be stated clearly what scale is considered. E.g., only those events, which appeared globally and altered several aspects of the Earth’s evolution, should be evaluated as catastrophes in the geologic history of the entire planet.

CAD. LAB. XEOL. LAXE 37 (2013)

Catastrophes versus events in the geologic past 173

The present essay offers a tentative treatment of the problem of geologic event scaling. Further conceptual discussion of catastrophes is necessary. But even more important is a balanced consideration of catastrophes and “ordinary” events. Focusing on only the former is not a way to clear understanding of the geologic past.

References

Acknowledgements The authors gratefully thanks J.R. Vidal Romaní (Spain) for his editorial support and P.F. Karrow (Canada) for his preliminary review of this paper. The help with literature provided by P.F. Karrow (Canada), W. Riegraf (Germany), A.J. van Loon (Netherlands/Poland), Q. Wang (China), and other colleagues is appreciated. Brief communications with E.A. Medley (USA) and R. Rovelli (USA), who both are thanked, allowed us to account for some very new results. D.A.R. acknowledges feedback from his students attending the lectures on geologic event analysis at the Southern Federal University (Russia). Appendix Two professional descriptions of the Pleistocene Lake Missoula and its catastrophic floods are available on-line at: http://www.glaciallakemissoula.org/ http://vulcan.wr.usgs.gov/Glossary/Glaciers/IceSheets/description_lake_missoula. html A balanced overview of debates on the hypothesis about the Younger Dryas extraterrestrial impact is available on-line at: http://www.csicop.org/si/show/did_a_ cosmic_impact_kill_the_mammoths/

Abbott, D. H. And Isley, A. E. (2002). Extraterrestrial influences on mantle plume activity. Earth and Planetary Science Letters, 205: 53–62. Aksu, A. E., Hiscott, R. N., Mudie, P. J., Rochon, A., Kaminski, M. A., Abrajano, T. and Yaşar, D. (2002). Persistent Holocene outflow from the Black Sea to the Eastern Mediterranean contradicts Noah’s Flood hypothesis. GSA Today, 12: 4–10. Alvarez, W. (2008). T. rex and the Crater of Doom. Princeton University Press, Princeton, 185 pp. Anderson, R. S. and Anderson, S.P. (2010). Geomorphology: The Mechanics and Chemistry of Landscapes. Cambridge University Press, Cambridge, 637 pp. Babin, C. (2007): Autour du catastrophisme: Des mythes et legendes aux sciences de la vie et de la Terre. Vuibert, ADAPT/ SNES, Paris, 170 pp. Bambach, R. K. (2006). Phanerozoic biodiversity and mass extinctions. Annual Review of Earth and Planetary Sciences, 34: 127–155. Beekwith, M. W. (1981). The Kumulipo: A Hawaiian Creation Chant. University of Hawaii Press, Honolulu, 257 pp. Belcher, C. M., Collinson, M. E. and Scott, A.C. (2004). Fireball passes and nothing burns—The role of thermal radiation in the Cretaceous-Tertiary event: Evidence from the charcoal record of North America. Geology, 31: 1061–1064. Belcher, C. M., Collinson, M. E. and Scott, A.C. (2005). Constraints on the thermal energy released from the Chicxulub impactor: new evidence from

174 Gutak et al.

multi-method charcoal analysis. Journal of the Geological Society, London, 162: 591–602. Benito, G. and O’Connor, J.E. (2003). Number and size of last-glacial Missoula floods in the Columbia River valley between the Pasco Basin, Washington, and Portland, Oregon. Geological Society of America Bulletin, 115: 624–638. Bennett, M. R. and Glasser, N. F. (2009). Glacial Geology: Ice Sheets and Landforms. Wiley-Blackwell, Chichester, 385 pp. Berggren, W. A. and van Couverig, J. A., Eds. (1984). Catastrophes and Earth History. Princeton University Press, 464 pp. Boggs, S., Jr. (2006). Principles of Sedimentology and Stratigraphy. Pearson Prentice Hall, Upper Saddle River, 662 pp. Bond, D. P. G., Wignall, P. B., Wang, W., Izon, G., Jiang, H.-S., Lai, X.-L., Sun, Y.-D., Newton, R. J., Shao, L.-Y., Védrine, S. and Cope, H. (2010a). The mid-Capitanian (Middle Permian) mass extinction and carbon isotope record of South China. Palaeogeography, Palaeoclimatology, Palaeoecology, 292: 282–294. Bond, D. P. G., Hilton, J., Wignall, P. B., Ali, J. R., Stevens, L. G., Sun, Y. and Lai, X. (2010b). The Middle Permian (Capitanian) mass extinction on land and in the oceans. Earth-Science Reviews, 102: 100–116. Bostrom, N. and Ćirković, M.M. (2008). Introduction. In: Bostrom, N. & Ćirković, M.M. (Eds.). Global Catastrophic Risks. Oxford University Press, Oxford, pp. 1–29. Bretz, J. H. (1969). The Lake Missoula floods and the channeled scabland.

CAD. LAB. XEOL. LAXE 37 (2013)

Journal of Geology, 77: 505–543. Broecker, W. S., Denton, G. H., Edwards, R. L., Cheng, H., Alley, R. B. and Putnam, A.E. (2010). Putting the Younger Dryas cold event into context. Quaternary Science Reviews, 29: 1078–1081. Butvilovskij, V. V. (1993). Paleogeografija poslednoge oledenenija i golotsena Altaja: sobytijno-katastrofitcheskaja model’ [Palaeogeography of the Last Glacial and the Holocene of the Altay: event-catastrophic model]. Tomskij universitet, Tomsk, 253 pp. (in Russian) Chunikhin, S. A. (2008). Taksonomitcheskaja kharakteristika granitsy permi i triasa po konkhostrakam [Taxonomic characteristics of the Permian/Triassic boundary by conchostracans]. In: Papin, Yu.S. (Ed.). Bio - i litostratigrafitcheskie rubezhi v istorii Zemli. TyumGNGU, Tyumen, pp. 261–265. (in Russian) Clague, J. J., Barendregt, R. W., Enkin, R. J. and Foit, N., Jr. (2003). Paleomagnetic and tephra evidence for tens of Missoula floods in southern Washington. Geology, 31: 247–250. Clapham, M. E., Shen, S. and Bottjer, D.J. (2009). The double mass extinction revisited: reassessing the severity, selectivity, and causes of the end-Guadalupian biotic crisis (Late Permian). Paleobiology, 35: 32–50. Clarke, G. K. C., Leverington, D. W., Teller, J. T. and Dyke, A. S. (2005). Paleohydraulics of the last outburst flood from glacial Lake Agassiz and the 8200 BP cold event. Quaternary Science Reviews 23, 389–407. Courtillot, V. (2007). Evolutionary Catastrophes - The Science of Mass

CAD. LAB. XEOL. LAXE 37 (2013)

Catastrophes versus events in the geologic past 175

Extinction. Cambridge University Press, Cambridge, 173 pp. Dury, G. H. (1980). Neocatastrophism? A further look. Progress in Physical Geography, 4: 391–413. Dypvik, H. and Jansa, L.F. (2003). Sedimentary signatures and processes during marine bolide impacts: a review. Sedimentary Geology, 161: 309–337. Erwin, D. H. (2006). Extinction: How Life on Earth Nearly Ended 250 Million Years Ago. Princeton University Press, Princeton, 306 pp. Fassett, J. E. (2009). New chronologic and stratigraphic evidence confirms the Paleocene age of the dinosaur-bearing Ojo Alamo Sandstone and Animas Formation in the San Juan Basin, New Mexico and Colorado. Palaeontología Electrónica, 12 (1-3A): 1–146. Fassett, J. E., Zielinski, R. A. and Budahn, J. R. (2002). Dinosaurs that did not die: Evidence for Paleocene dinosaurs in the Ojo Alamo Sandstone, San Juan Basin, New Mexico. Geological Society of America Special Paper, 356: 307–336. Firestone, R. B., West, A., Kennett, J. P., Becker, L., Bunch, T. E., Revay, Z. S., Schultz, P. H., Belgya, T., Kennett, D. J., Erlandson, J. M., Dickenson, O. J., Goodyear, A. C., Harris, R. S., Howard, G. A., Kloosterman, J. B., Lechler, P., Mayewski, P. A., Montgomery, J., Poreda, R., Darrah, T., Que Hee, S. S., Smith, A. R., Stich, A., Topping, W., Wittke, J. H. and Wolbach, W. S. (2007). Evidence for an extraterrestrial impact 12,900 years ago that contributed to the megafaunal extinctions and the

Younger Dryas cooling. Proceedings of the National Academy of Sciences, 104: 16016–16021. Flores, J.-A., Sierro, F. J. and Gersonde, R. (2002). Calcareous plankton stratigraphy around the Pliocene “Eltanin” asteroid impact area (SE Pacific): documentation and application for geological and paleoceanographic reconstruction. Deep Sea Research Part II: Topical Studies in Oceanography, 49: 1011–1027. Görür, N., çağatay, M. N., Emre, Ö., Alpar, B., Sakınç, M., Islamoğlu, Y., Algan, O., Erkal, T., Keçer, M., Akkök, R. and Karlık, G. (2001). Is the abrupt drowning of the Black Sea shelf at 7150 yr BP a myth? Marine Geology, 176: 65–73. Grosvald, M. G. (1999). Evrazijskie gidrosfernye katastrofy i oledenenie Arktiki [Eurasian hydrospheric catastrophes and the glaciation of Arctic]. Nautchnyj mir, Moskva, 128 pp. (in Russian) Gutak, Ja. M. (2008). Diluvial’nyj sedimentogenez v istorii Zemli [Dilavial sedimentation in the history of the Earth]. In: Japaskurt, O.V. & Maslov, A.V. (Eds.) .Tipy sedimentogeneza i litogeneza i ikh evoljutsija v istorii Zemli. Vol. 1. IGG UrO RAN, Ekaterinburg, pp. 187-189. (in Russian) Gutak, Ja. M. and Antonova, V. A. (2006a). Krasnotsvetnye otlozhenija v pribrezhno-morskokih fatsijakh (model’ formirovanija na primere pozdnedevonskikh otlozhenij Kuzbassa) [Red-coloured deposits in the nearshore facies (formation model by example of Late Devonian deposits of the Kuzbass)]. Izvestija Bijskogo otdelenija Russkogo geografitcheskogo obtschestva, 26: 95-97. (in Russian)

176 Gutak et al.

Gutak, Ja. M. and Antonova, V. A. (2006b). Red-coloured adjournment in seashore facies (formation model on an example of the Upper Devonian adjournment of Kuzbass). Proceedings of the XVIIIth Congress of the CarpathianBalkan Geological Association, September 3–6, 2006, Belgrade, Serbia. Belgrade, pp. 193–196. Gutak, Ja. M., Antonova, V. A., Bagmet, G. N., Gabova, M. F., Savitskij, V. R. and Tolokonnikova, Z. A. (2008). Otcherki po istoritcheskoj geologii Kemerovskoj oblasti [Discourses on the historical geology of the Kemerovo Region]. Izdatel’stvo KuzGPA, Novokuznetsk, 133 pp. (in Russian) Hallam, A. (2005). Catastrophes and Lesser Calamities - The Causes of Mass Extinctions. Oxford University Press, Oxford. 240 pp. Hallam, A. and Wignall, P.B. (1997). Mass Extinctions and their Aftermath. Oxford University Press, Oxford, 320 pp. Hickey, L. J. (1992). Dragged toward Armageddon: A Changing Paleontological Viewpoint on Catastrophism. AAPG Anuual Convention. Abstracts. Calgary, pp. 55– 56. Holliday, V. T., Kring, D. A., Mayer, J. H. and Goble, R.J. (2005). Age and effects of the Odessa meteorite impact, western Texas, USA. Geology, 33: 945–948. Houghton, J. (2009). Global Warming. The Complete Briefing. Cambridge University Press, Cambridge, 438 pp. Jablonski, D. (2004). The evolutionary role of mass extinctions: disaster, recovery and something in-between. In: Taylor, P.D. (Ed.). Extinctions in the history of life. Cambridge University Press, Cambridge, pp. 151–177.

CAD. LAB. XEOL. LAXE 37 (2013)

Karrow, P. F. (1989). Quaternary continental stratigraphy and eocatastrophism. Quaternary Science Reviews, 8: 277–282. Keller, G. (2008). Cretaceous climate, volcanism, impacts, and biotic effects. Cretaceous Research, 29: 754–771. Kendall, R. A., Mitrovica, J. X., Milne, G. A., Tornqvist, T. E. and Li, Y. (2008). The sea-level fingerprint of the 8.2 ka climate event. Geology, 36: 423–442. Kennett, D. J., Kennett, J. P., West, G. J., Erlandson, J. M., Johnson, J. R., Hendy, I. L., West, A., Culleton, B. J., Jones, T. L. and Stafford, T. W., Jr. (2009). Wildfire and abrupt ecosystem disruption on California’s Northern Channel Islands at the Allerød-Younger Dryas boundary (13.0-12.9 ka). Quaternary Science Reviews, 27: 2530–2545. LeGrande, A. (2009). The 8,200Year BP Event. In: Gornitz, V., Ed. Encyclopedia of Paleoclimatology and Ancient Environments. Springer, Dordrecht, pp. 938–943. Lehnert, O., Männik, P., Joachimski, M. J., Calner, M. and Frýda, J. (2010). Palaeoclimate perturbations before the Sheinwoodian glaciation: A trigger for extinctions during the ‘Ireviken Event’. Palaeogeography, Palaeoclimatology, Palaeoecology, 296: 320–331. Lericolais, G., Bulois, C., Gillet, H. and Guichard, F. (2009). High frequency sea level fluctuations recorded in the Black Sea since the LGM. Global and Planetary Change, 66: 65–75. Luo, G., Lai, X., Shi, G. R., Jiang, H., Yin, H., Xie, S., Tong, J., Zhang, K., He, W. and Wignall, P.B. (2008). Size variation of conodont elements of the Hindeodus-Isarcicella clade

CAD. LAB. XEOL. LAXE 37 (2013)

Catastrophes versus events in the geologic past 177

during the Permian-Triassic transition in South China and its implication for mass extinction. Palaeogeography, Palaeoclimatology, Palaeoecology, 264: 176–187. Machalski, M. and Heinberg, C. (2005). Evidence for ammonite survival into the Danian (Paleogene) from the Cerithium Limestone at Stevns Klint, Denmark. Bulletin of the Geological Society of Denmark, 52: 97–111. Machalski, M., Jagt, J. W. M., Heinberg, C., Landman, N. H. and Håkansson, E. (2009). Dańskie amonity - obecny stan wiedzy i perspektywy badań. Przegląd Geologiczny, 57: 486-493. Marriner, N., Morhange, C. and Skrimshire, S. (2010). Geoscience meets the four horsemen?: Tracking the rise of neocatastrophism. Global and Planetary Change, 74: 43–48. Medley, E. A. and Burns, S. F. (2010). Ancient cataclysmic floods in the Pacific Northwest; ancestors to the Missoula Floods. Geological Society of America Abstracts with Programs, 42 (5), 310. Milne, A. (2000). Doomsday: The Science of Catastrophic Events. Praeger, Westport, 208 pp. Munnecke, A., Calner, M., Harper, D. A. T. and Servais, T. (2010). Ordovician and Silurian sea-water chemistry, sea level, and climate: A synopsis. Palaeogeography, Palaeoclimatology, Palaeoecology, 296: 389–413. Napier, W. (2008). Hazards from comets and asteroids. In: Bostrom, N. & Ćirković, M.M. (Eds.). Global Catastrophic Risks. Oxford University Press, Oxford, pp. 222–237. O’Connor, J. E. and Baker, V. R. (1992). Magnitudes and implications of peak discharges from glacial Lake

Missoula. Geological Society of America Bulletin, 104: 267–279. Ogg, J. G., Ogg, G. and Gradstein, F. M. (2008). The Concise Geologic Time scale. Cambridge University Press, Cambridge, 177 pp. Pluhar, C. J., Bjornstad, B. C., Reidel, S. P., Coe, S. R. and Nelson, P. B. (2006). Magnetostratigraphic evidence from the Cold Creek bar for onset of ice-age cataclysmic floods in eastern Washington during the early Pleistocene. Quaternary Research, 65: 123–135. Posner, R. (2004). Catastrophe:Risk and Response. Oxford University Press, Oxford, 322 pp. Racki, G. (2009). Wielkie wymimierania i ich przyczyny. Kosmos, 58: 529–545. Raup, D. W. and Sepkoski, J. J., Jr. (1982). Mass extinctions in the marine fossil record. Science, 215: 1501–1503. Rey, J. and Galeotti, S., Eds. (2008). Stratigraphy terminology and practice. TECHNIP, Paris, 166 pp. Rovelli, R., Garb, M.P. and Landman, N.H. (2010). Death and recovery at the K/T boundary: evidence from new sites in New Jersey. Geological Society of America Abstracts with Programs, 42 (5), 255. Ruban, D. A. (2006). Sobytijnyj analiz v naukakh o Zemle [Event analysis in the Earth Sciences]. UPL RGU, Rostov-naDonu, 18 pp. (in Russian) Ruban, D. A. (2008). Silurian biotic crises in the northern Greater Caucasus (Russia): a comparison with the global record. Paleontological Research, 12: 387–395. Ruban, D. A. and Tyszka, J. (2005). Diversity dynamics and mass extinctions of the Early-Middle Jurassic foraminifers: A record from the Northwestern Caucasus.

178 Gutak et al.

Palaeogeography, Palaeoclimatology, Palaeoecology, 222: 329–343. Rudoy, A. N. (2002). Glacier-dammed lakes and geological work of glacial superfloods in the Late Pleistocene, Southern Siberia, Altai Mountains. Quaternary International, 87: 119–140. Ryan, W. and Pitman, W. C., III (1999). Noah’s Flood: The New Scientific Discoveries about the Event that Changed History. Simon and Schuster, New York, 319 pp. Ryan, W. B. F., Major, O. C., Lericolais, G. and Goldstein, S. L. (2003). Catastrophic flooding of the Black Sea. Annual Review of Earth and Planetary Sciences, 31: 525–554. Schönlaub, H.-P. (1996). Scenarios of Proterozoic and Paleozoic catastrophes: A review. Abhandlungen der Geologischen Bundesanstalt, 53: 59–75. Schulte, P., Alegret, L., Arenillas, I., Arz, J. A., Barton, P. J., Bown, P. R., Bralower, T. J., Christeson, G. L., Claeys, P., Cockell, C. S., Collins, G. S., Deutsch, A., Goldin, T. J., Goto, K., Grajales-Nishimura, J. M., Grieve, R. A. F., Gulick, S. P. S., Johnson, K. R., Kiessling, W., Koeberl, C., Kring, D. A., MacLeod, K. G., Matsui, T., Melosh, J., Montanari, A., Morgan, J. V., Neal, C. R., Nichols, D. J., Norris, R. D., Pierazzo, E., Ravizza, G., Rebolledo-Vieyra, M., Reimold, W. U., Robin, E., Salge, T., Speijer, R. P., Sweet, A. R., Urrutia-Fucugauchi, J., Vajda, V., Whalen, M. T. and Willumsen, P.S. (2010). The Chicxulub Asteroid Impact and Mass Extinction at the Cretaceous-Paleogene Boundary. Science, 327: 1214–1218.

CAD. LAB. XEOL. LAXE 37 (2013)

Sepkoski, J. J., Jr. and Raup, D. (1986). Periodicity in mass extinction events. In: Elliott, D. K. (Ed.). Dynamics of Extinction. Wiley, New York, pp. 3–36. Stanley, S. M. and Yang, X. N. (1994). A double mass extinction at the end of the Paleozoic Era. Science, 266: 1340– 1344. Stow, D. (2010). Vanished Ocean: How Tethys Reshaped the World. Oxford University Press, Oxford, 300 pp. Surovell, T. A. and Holliday, V. T. (2009). Non-reproducibility of Younger Dryas extraterrestrial impact results. Geological Society of America Abstracts with Programs, 41( 7): p. 595 Teller, J. T., Boyd, M., Yang, Z., Kor, P. S. G. and Fard, A. M. (2005). Alternative routing of Lake Agassiz overflow during the Younger Dryas: new dates, paleotopography, and a reevaluation. Quaternary Science Reviews, 24: 1890–1905. Vajda, V., Raine, J. I. and Hollis, C. J. (2001). Indication of Global Deforestation at the Cretaceous-Tertiary Boundary by New Zealand Fern Spike. Science, 294: 1700–1702. van Loon, A. J. (1999). The meaning of `abruptness’ in the geological past. Earth-Science Reviews, 45: 209–214. van Loon, A. J. (2009). Reflections on subglacial megafloods: their possible cause, occurrence, and consequence for the global climate. Geologos, 15, 115– 128. Ward, S. N. and Asphaug, E. (2002). Impact tsunami-Eltanin. Deep Sea Research Part II: Topical Studies in Oceanography, 49: 1073–1079. Wolbach, W. S., Gilmour, I. and Anders, E. (1990). Major wildfires at the Cretaceous/Tertiary boundary. In: Sharpton, V.L. & Ward, P.D. (Eds.). Global Catastrophes in Earth

CAD. LAB. XEOL. LAXE 37 (2013)

Catastrophes versus events in the geologic past 179

History; An Interdisciplinary Conference on Impacts, Volcanism, and Mass Mortality. Geological Society of America Special Paper, 247: 391–400. Xiong, C. and Wang, Y. (2011). Permian–Triassic land-plant diversity in South China: Was there a mass extinction at the Permian/Triassic boundary? Paleobiology, 37: 157–167.

Yanko-Hombach, V., Gilbert, A. S., Panin, N. and Dolukhanov, P. M., Eds. (2007). The Black Sea Flood Question: Changes in Coastline, Climate, and Human Settlement. Springer, Dordrecht, 971 pp. Zhang, Y. (2005). The age and accretion of the Earth. Earth-Science Reviews, 59, 235–263.

Cadernos Lab. Xeolóxico de Laxe Coruña. 2013. Vol. 37, pp. 181 - 196

ISSN: 0213-4497

Contribution to the study of Fe-Ti mineralization from S. Torpes beach (Sines, Setúbal, Portugal)

MOURA, A.1 and PINTO, F.2

(1) Departamento de Geociências, Ambiente e Ordenamento do Território. Faculdade de Ciências da Universidade do Porto. Centro de Geologia da Universidade do Porto. Rua do Campo Alegre 4167-007 Porto, Portugal (2) Mestrando no 2º Ciclo em Geologia da Faculdade de Ciências da Universidade do Porto (Portugal) em 2012-13.

Abstract Three samples from the natural heavy concentration of the upper back sands at S.Torpes beach was analysed by microscopy, MEV and microprobe in order to characterize the mineralogical composition of the ore minerals. Because of the strong homogeneous granulometry the sand was only divided in two fractions, above and below the 125 micron sieve. Each fraction was subjected to magnetic separation by magnet hand and heavy liquid (bromoform). The paramagnetic fraction was subjected to Frantz electromagnet. Magnetic and paramagnetic fractions were studied in reflection microscopy, SEM and electronic microprobes. These techniques showed that the heavy fraction of these sands is composed on average by magnetite (71%), ilmenite (12%), hematite (8%) and mixed grains (9%). Textural aspects of the three main mineral compositions as well as its chemical composition and structural formula were further characterized. We also identified minor amounts of monazite and alteration minerals (rutile, psudorutile, ilmenorutile and titanite) and sulphides, all in very small amounts. It was possible to determine the mineralogical “average” composition of the sand combining the results of this study with the study of Pombo et al. (2006). Key words: Sines; beach; opaque minerals; ilmenite; magnetite.

182 Moura and Pinto

1. INTRODUÇÃO A praia de S. Torpes (concelho de Sines, distrito de Setúbal) encerra a única ocorrência significativa de areias titaníferas da costa ocidental da Península Ibérica. No intuito de melhor conhecer esta mineralização, foi feito um estudo de caracterização dos concentrados naturais de minerais pesados. O trabalho de CASTRO LEANDRO (1942) constitui, tanto quanto sabemos, o único estudo efectuado sobre esta ocorrência de Fe-Ti. Trata-se de uma “breve notícia” na qual o autor refere a localização, enquadramento geológico, bem como a existência de magnetite e ilmenite na areia e fornece uma análise química das areias negras. O local aparentemente só voltou a ser estudado já este século, em dois trabalhos de cariz sedimentológica (POMBO et al., 2006 e CASCALHO et al., 2006). No primeiro desses estudos os autores amostraram quatro locais dos quais o denominado G3 corresponde à área da praia de S. Torpes. Nesse trabalho os autores caracterizaram apenas a fracção de minerais pesados transparentes. CASCALHO et al., 2006 estudaram cerca de três dezenas de amostras de praia e da plataforma continental entre Caminha e Vila Real de Santo António, das quais três da área emersa da costa próxima de Sines. Ambos os trabalhos tiveram como objectivo caracterizar os processos de dinâmica costeira através do estudo de associações de minerais pesados transparentes. O presente trabalho tem como principal objectivo caracterizar os minerais pesados opacos (metálicos) das areias titaníferas da praia de S. Torpes (Fig. 1) tendo como objecto de estudo uma amostragem de concentrados naturais colhidos in situ. 2. ENQUADRAMENTO GEOLÓGICO

CAD. LAB. XEOL. LAXE 37 (2013)

REGIONAL A geologia da área é dominada pelo maciço magmático máfico de Sines que aflora a cerca de 8 Km da praia de S. Torpes. Na área da praia e da duna correlativa, são abundantes os sedimentos soltos (areias e cascalhos) de idade Plistocénico - Holocénico (INVERNO et al., 1993), que estão assentes sobre estratos metassedimentares do Mesozóico e do Paleozóico tendo estes uma distribuição muito limitada, em afloramento, na área. O maciço ígneo de Sines é um complexo gabro-diorítico zonado, com cerca de 10 km2 de área emersa que se prolonga alguns quilómetros para ocidente, sob o mar. O maciço foi estudado por CANILHO (1972, 1989). Fazem ainda parte do maciço, sienitos distribuídos na parte externa, e filões de brechas ígneas de natureza básica. 3. METODOLOGIA DE TRABALHO A metodologia compreendeu duas partes, uma fase inicial em que se utilizaram técnicas de preparação das amostras (fase 3.2 a 3.5) e uma fase posterior de técnicas de análise (3.6 a 3.9). 3.1. Amostragem A praia de S. Torpes tem um alinhamento NNW-SSE e dimensões médias de 1500 x 50 km (Fig. 2). Foram colhidas dez amostras na camada de areias negras superficial (concentrado natural com ~3cm de espessura). De modo a diminuir a contaminação com minerais transparentes, teve-se o cuidado de recolher material no centímetro mais superficial. A amostragem foi efectuada num período entre marés-vivas, altura em que o

CAD. LAB. XEOL. LAXE 37 (2013)

concentrado natural de minerais pesados é mais espesso. As amostras foram colhidas espaçadas ~100 m ao longo do alinhamento

Contribution to the study of Fe-Ti mineralization 183

médio da praia. Foram estudadas três dessas amostras, tomadas aleatoriamente.

Fig. 1. Mapa geológico simplificado da região. Baseado em Inverno et al., 1993.

184 Moura and Pinto

3.2. Separações granulométricas Numa observação macroscópica é notório que a areia é bastante bem calibrada e que o diâmetro do seu grão corresponde a uma areia fina. No intuito de determinar a distribuição da areia por diferentes fracções granulométricas utilizamos os peneiros de malha 250, 125 e 63 micra. Posteriormente, face aos resultados obtidos (ver mais à frente) optamos por considerar apenas duas fracções: maior e menor que 125 micra. 3.3. Separações com íman de Nd-Fe-B Dado que as amostras correspondiam a concentrados naturais, quase completamente negros e em grande parte constituídos por magnetite, optamos por fazer uma separação dessa componente altamente magnética. Este procedimento foi efectuado de modo a optimizar o funcionamento do separador electromagnético Frantz. Simultaneamente conseguiu-se assim diminuir a quantidade de amostra submetida à separação por líquidos pesados. Na separação por íman de mão, colocou-se cada fracção de cada amostra numa superfície plana e horizontal com uma área suficientemente grande de modo a permitir que os grãos ficassem suficientemente espaçados entre si. Este procedimento teve em vista diminuir a hipótese de se atraírem minerais com fraca susceptibilidade magnética, “arrastados” pelos mais magnéticos. 3.4. Separações por líquidos pesados O líquido denso utilizado foi o bromofórmio (CHBr3) a 96%, que apresenta uma densidade de 2,89. Este fluido faz com que as partículas de densidade inferior flu-

CAD. LAB. XEOL. LAXE 37 (2013)

tuem, as de superior afundem e as de igual, permaneçam em suspensão. Permite em particular a eliminação do quartzo, feldspato e mica. 3.5. Separações electromagnéticas Foi utilizado um electroíman isodinâmico Frantz de 115V e 2,5A. Fizeram-se passar cada uma das fracções não atraídas pelo íman de mão. Utilizaram-se inclinações entre 10º e 15º para um e outro eixo do aparelho, e uma amperagem de 1,1A a que corresponde uma potência de 125W. O objectivo desta técnica é separar cada amostra em duas fracções, uma paramagnética e outra diamagnética (por vezes designada não magnética). 3.6. Estudo na lupa binocular Esta técnica foi utilizada para aferir a performance do separador Frantz, isto é para garantir a eficácia da amperagem aplicada às amostras em estudo. 3.7. Estudo metalográfico (microscopia em luz reflectida) Foi uma das técnicas mais importantes utilizadas na identificação e caracterização dos grãos de minerais pesados opacos presentes nas amostras. Permitiu também estimar as proporções relativas das diferentes fases minerais em cada fracção e no total da amostra. Na fracção magnética de cada amostra identificaram-se 300 grãos da fracção < 125 micra e 300 grãos da fracção > 125 micra. Na fracção paramagnética, e para cada amostra, estudaram-se 100 grãos de cada uma das fracções maior e menor que 125 micra.

CAD. LAB. XEOL. LAXE 37 (2013)

3.8. Microscopia electrónica de varrimento (MEV) Foi utilizado um microscópio de modelo JEOL JSM 35C / Noran Voyager, do Centro de Materiais da Universidade do Porto (CEMUP), na observação de imagens produzidas por electrões retrodifundidos (ER). Foram observadas as amostras em lâmina delgada polida da fracção paramagnética e em secção polida da fracção magnética, ambas da granulometria maior que 125 micra. 3.9. Análises na microssonda eletrónica Foi utilizado uma microssonda de modelo JEOL JXA-8500 F equipada com 5 espectrómetros WDS (wavelenghts dispersive spectrometer) com 10 cristais analisadores e um espectrómetro EDS (energy dispersive spectrometer) do Laboratório Nacional de Energia e Geologia (LNEG). Foram efectuadas cerca de duas dezenas de análises pontuais em vários grãos de três amostras (duas

Contribution to the study of Fe-Ti mineralization 185

da fracção magnética e uma da paramagnética). O uso desta técnica teve como principal objectivo identificar pequenas inclusões e intercrescimentos em vários minerais, bem como obter análises químicas pontuais dos elementos principais das fases analisadas. 4. RESULTADOS Face à homogeneidade da granulometria da areia, utilizamos algumas amostras num teste passando cada uma delas pelos três peneiros referidos no ponto 3.2. Oitenta e nove por cento da massa das amostras passaram no peneiro 250 micra e menos de 1% passou no peneiro de 63 micra. Visto que a fracção > 250 micra correspondia apenas a 11% (em peso) das amostra-teste e por não ser provável que a fracção granulométrica imediatamente inferior tivesse uma mineralogia diferente, optamos por utilizar apenas o peneiro 125 micra na separação granulométrica, ficando assim com uma fracção superior e outra inferior a este calibre (Fig. 3).

186 Moura and Pinto

Fig. 2. Imagem Google Earth da praia de S. Torpes.

CAD. LAB. XEOL. LAXE 37 (2013)

CAD. LAB. XEOL. LAXE 37 (2013)

Contribution to the study of Fe-Ti mineralization 187

Fig. 3. Granulometria (em percentagem) das amostras estudadas em função do peneiro 125 micra. À esquerda encontra-se representada o fracionamento granulométrico obtido em quatro amostras teste em que se usaram os peneiros 250 e 63 micra no intuito de estimar a quantidade de material acima e abaixo daqueles peneiros.

Tendo em vista separar os minerais pesados dos restantes, passou-se cada uma das quatro fracções de cada amostra (Tabela 1) no bromofórmio. Verificou-se, como esperado, que a quase totalidade dos grãos das fracções magnéticas apresentavam uma densidade superior à do líquido, afundando. Em cinco de seis amostras remanescentes (cuja areia não foi atraída pelo íman de mão) verificou-se uma situação idêntica, tendo afundado 99,50% dos grãos.

Na outra amostra verificou-se que 37 % em peso (5,2 g) eram de areias menos densas que o bromofórmio. Assim, verificamos que apenas numa das amostras (amostra 1) foi incorporada, na amostragem efectuada no terreno, uma percentagem de minerais leves (14%) com alguma relevância. Tendo em vista a separação por susceptibilidade magnética dos grãos, sujeitaram-se as fracções que não foram atraídas pelo íman de mão à ação do separador eletromagnético (Tabela 2).

188 Moura and Pinto

CAD. LAB. XEOL. LAXE 37 (2013)

Amostra 1 2 3

< 125 micra

> 125 micra

TOTAL

mag.

rem.

mag.

rem.

mag.

rem.

84%

16%

43%

56%

57%

43%

12,741 g 43%

25,674 g

57%

23%

15,684 g 47%

77%

23,086 g

53%

23%

15,315 g

77%

22,901 g

38,415 g 31%

69%

38,770 g 33%

67%

38,216 g

Tabela 1. Pesos das diferentes frações das amostras analisadas (mag. – fração atraída pelo íman de mão; rem. – fração remanescente não atraída pelo íman de mão).

Amostra

125 micra remanescente

TOTAL remanescente

Paramag.

Diamag.

Paramag.

Diamag.

Paramag.

Diamag.

1

83 13

17 3

92 35

8 11

91

9

2

92 53

8 5

63 49

37 29

73

27

3

90 48

10 5

61 48

39 31

70

30

Tabela 2. Resultados, em percentagem, da separação pelo eletroíman Frantz, das amostras remanescentes, correspondentes ao material que não foi atraído pelo íman de mão. Paramag.- fração paramagnética, Diamag.fração diamagnética. Os valores inferiores dizem respeito à percentagem de acordo com o total da amostra (soma das frações Paramag. + Diamag. + Magnética).

O estudo metalográfico das frações magnética e paramagnética de cada uma das frações (125 micra), totalizou a identificação de 1800 grãos opacos correspondente à fração magnética e 600 minerais opacos da fração paramagnética. Como se verifica nos histogramas da Fig. 4, não houve uma diferença significativa na composição mineralógica das frações maior e menor que 125 micra. Verifica-se assim que a fração magnética é composta por ~78% de magnetite e ~7% de ilmenite. A fração para-

magnética compreende ~52% de magnetite e ~28% de ilmenite. Na globalidade das frações magnética e paramagnética verificase a existência de ~71% de magnetite, ~12% de ilmenite, sendo os restantes ~17% constituídos por hematite (8%), grãos de ilmenite com magnetite (5%), grãos de hematite com magnetite (2%) e grãos de ilmenite com hematite (2%). Os estudos no MEV foram efetuados sobre as frações paramagnética e magnética. Foram identificados grãos de mag-

CAD. LAB. XEOL. LAXE 37 (2013)

netite, hematite, ilmenite, rútilo, monazite, titanite, enstatite e biotite. Obteve-se também uma análise semi-quantitativa e pontual em vários grãos. Em cinco análises em magnetites verificou-se que o teor em titânio variava no intervalo 2-7 % e o teor em ferro entre 56 e 70 %. Em 11 análises efectuadas em grãos de ilmenite verificou-

Contribution to the study of Fe-Ti mineralization 189

se que o teor em titânio variava entre 30 e 37 % e o de ferro entre 22 e 38 %. Em quatro análises efectuadas em grãos de rútilo observaram-se teores de 43 a 58 % Ti e