Advances in Active Tectonics and Speleotectonics
Book of Abstracts
Ivo Baroň, Kurt Decker, Esther Hintersberger,
Ivanka Mitroviċ, & Lukas Plan (Eds.)
Natural History Museum Vienna & University of Vienna, Austria
20. – 24. September, 2015
Advances in Active Tectonics and Speleotectonics
Date: September 20 – 24, 2015
Venue and arrival Natural History Museum Vienna Burgring 7 1010 Vienna, Austria
Public transport – Subway station U2 and U3 “Volkstheater”, tram & bus stop 1, 2, 46, 49, 71, D, 48A “Dr.-Karl-Renner-Ring”, Public transport router planner: www.anachb.at Arrival by car – we suggest parking your car in your hotel considering regulated parking in the center of Vienna (http://www.wien.gv.at/english/transportation/parking/shortterm.htm)
Program overview
• Sunday, 20 September Ice breaker party (including registration and Speleotect movie projection) Meeting point at 18:30 at the “Gate” (facing Burgring street – see map below)
• Monday, 21 September 8:00 registration; 8:30 Oral presentations – presentation room (next to main visitors entrance – see map below) Afternoon: Field trip to the central Vienna Basin – meeting at 13:30 at the “Gate” (visit to Heurigen-Restaurant included)
• Tuesday, 22 September 8:30 Oral and poster sessions – presentation room
• Wednesday - Thursday, 23 - 24 September Field trip to southern Vienna Basin and surroundings (Eisenstein and Emmerberg Caves), and Periadriatic Fault (Obir Caves & Dobratsch; Carinthia) Meeting point on Wednesday at 8:00 at the “Gate” (facing Burgring street – see map below), transport back to Vienna with latest arrival on Thursday at 21:00 (please consider it when booking your next transport or accommodation, individual arrangement upon request possible).
Registration desk will be opened on Sunday from 18:30 to 20:00 next to the Gate (entrance from the Burgring street) and on Monday from 8 to 8:30 next to the Main visitors entrance
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Organizers
Ivo Baroň (Natural History Museum, Vienna) Kurt Decker (University of Vienna) Esther Hintersberger (University of Vienna) Ivanka Mitroviċ (Natural History Museum and University of Vienna) Lukas Plan (Natural History Museum, Vienna)
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AATS Workshop Program:
Sunday 20 September, 2015 19:00 23:59 Ice-breaker party and the Speleotect movie projection (meeting at Gate at 18:30 p.m.)
Monday 21 September, 2015 8:30 8:40 Invitation, acknowledgements and organizing remarks Organizers 8:40 9:20 Key note talk: State-of-arts of the active-tectonics studies Raul Perez-Lopez 9:20 9:35 Coffee break
Near-surface and ground-surface active tectonics: 9:35 10:15 Earthquake research from space by using InSAR Henriette Sudhaus (DE) 10:15 10:30 Active Tectonics in the Eastern Alps and Surroundings Kurt Decker (AT) 10:30 11:10 Coffee break 11:10 11:30 Sediment burial dating as a tool in active tectonics research - chances and challenges Lüthgens, C., Neuhuber, S., Braumann, S., Fiebig, M.
Jamšek Rupnik P., Atanackov J., Jež J., Milanič B., 11:30 11:50 Database of active faults in Slovenia Celarc B., Novak M. & Bavec M. Quaternary tectonics on the Sudetic Marginal Fault as revealed by trenching and Štěpančíková P., Tábořík P., Hartvich F., Stemberk J., 11:50 12:10 geophysics (Kamenička site) Corominas O. Fault linkage model of strike-slip and normal faults in the Vienna Basin (Austria) based on Hintersberger E., Decker K., Lomax J., Fiebig M., 12:10 12:30 paleoseismological constraints Lüthgens C.
12:30 13:30 Lunch 13:30 20:00 Excursion Vienna Basin
Tuesday 22 September, 2015 Speleotectonics & Speleoseismites I.: 8:30 9:10 Cave Damage Caused by Neotectonics and Earthquakes ̶ or Not? Anfried Becker (CH) Quaternary faulting in the Tatra Mts. from the perspective of the cave morphology and 9:10 9:50 Szczygieł J. fault-slip analysis 9:50 10:10 Coffee break 10:10 10:25 Quaternary fault activity revealed in caves in the Eastern Alps Plan L., Baroň I., Grasemann B., Mitrovic I. Are we able to identify co-seismic deformation in caves? Comparative Study of naturally 10:25 10:45 Mitrovic I., Plan L., Grasemann B., Baroň I. and experimentally sheared calcite speleothems 10:45 11:00 Coffee break
Monitoring of active tectonics and related phenomena: 11:00 11:40 Slow aseismic fault slip recorded across Europe Josef Stemberk, Mathew D. Rowberry (CZ) 11:40 12:00 Relationship between CO2 content in fault caves and microseismicity Perez-Lopez R. 12:00 12:20 Monitoring of caves in mining areas: Case studies from Brazil Auler A.S., Souza T.A.R. Baroň I., Plan L., Grasemann B., Mitrovic I., Stemberk 12:20 12:40 Current fault activity observed in caves of the Eastern Alps J.
12:40 14:00 Lunch
Speleotectonics & Speleoseismites II.: Elisa Kagan (IL) et Bar-Matthews M., Ayalon A., 14:00 14:40 Soreq Caves: a 200,000 year-long dated speleo-seismite earthquake archive Braun Y., Agnon A. Braun Y., Kagan E., Bar-Matthews M., Ayalon A., Dating speleoseismites near the Dead Sea transform and the Carmel fault: clues to 14:40 15:00 Agnon A. coupling of a plate boundary and its branch
15:00 15:15 Coffee break Pérez-López R., Garduño-Monroy V.H., Rodríguez- 15:15 15:35 Mega earthquake affecting the Cacahuailpa cave, Mexico Pascua M.A., Israde-Alcántara I. Gribovszki K., Bokelmann G., Mónus P., Kóvacs K., 15:35 15:55 Constraints on Long-Term Seismic Hazard From Vulnerable Stalagmites Konečný P., Lednická M., Hegymegi E., Novák A. 15:55 16:10 Coffee break
Poster session: Small-scale seismites in cave clastic deposits: preliminary results from the Kalacka Cave, 16:10 16:15 Szczygieł J., Wróblewski W., Mendecki M. Tatra Mts., Poland 16:15 16:20 The seismothems of the Emine-Bair-Khosar Cave (Crimea) Kalush I., Ridush B. Recent evidences of Plio-quaternary tectonic activity in the Constantine Basin (North-East 16:20 16:25 Mohammedi Y., Djellit H., Hamidatou M. of Algeria) Pérez-López R., Bañón E., Patyniak M., Durán-Valsero 16:25 16:30 Speleoseismology of Benis cave: evidence of a M6 paleoearthquake 75 yr BP J.J., Giner-Robles J.L., Rodríguez-Pascua M.A., Martínez-Díaz J.J. Speleotectonic constrains from the ‘Tripa tou Fournari’ cave, Thessaloniki, Greece (a 16:30 16:35 Pennos C., Lauritzen S.-E., Gkarlaouni C., Sotidiadis Y. preliminary report). 16:35 16:40 Morphostructure analysis of Waitzendorf and Diendorf faults - Some preliminary results Stemberk J. jr., Decker K., Štěpančíková P. Installation of an automated fault displacement monitoring system at a geological test 16:40 16:45 Rowberry M.D., Martí X., Stemberk J. site in northern Bohemia 16:45 17:05 Coffee break and discussion
Active tectonics and speleogenesis: Age of the allogenic quartz pebbles from Snežna jama, Huda luknja and Špehovka for 17:05 17:25 Mihevc A., Häuselmann P., Fiebig M. implication of tectonic uplift Kamnik Alps and Karavanke, Slovenia 17:25 17:45 Active tectonics and hypogean caves: a view from the Apennines of Italy Menichetti M. Non karst caves of the Polish Flysch Carpathians and their connection with stages of mass 17:45 18:05 Margielewski W., Urban J., Szura C. movement formation: tectonic constraints, dating and classification Tectonic inception and the one-eighth relationship that constrains deglacial neotectonism 18:05 18:25 Faulkner T. and cave development in most Caledonide marbles 3
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Advances in Active Tectonics and Speleotectonics 2015, Vienna, Austria
Monitoring of caves in mining areas: Case studies from Brazil
Augusto S. Auler1 & Tatiana A. R. Souza1 1 Instituto do Carste, Rua Aquiles Lobo 197, Belo Horizonte, 30150-160, Minas Gerais, Brazil, [email protected]
Under Brazilian legislation, subsoil features, including caves and mineral deposits, belong to the union and can only be exploited according to strict laws. Detailed geological and biological studies should be performed in each cave in order to determine its significance level: Maximum, High, Medium or Low (Auler & Piló, 2015). No environmental impact is allowed in maximum significance caves and a buffer zone must be established, taking into consideration the preservation of cave dynamics, including hydrogeology, structural integrity, ecosystem conservation, etc. Although caves of high, medium and low significance can be subject to environmental impacts, buffer protection zones must also be applied until the approval of studies, a complex procedure that may take at least 1.5 years. Out of the many factors that have to be taken into consideration in establishing the protection buffer zone, cave integrity in relation to present or future blasting scenarios is among the most complex. Because these new laws came into application in 2008, it is extremely common for caves to be located in close proximity (or even inside) quarries, resulting in mining closure and considerable financial losses. Variations related to rock type (caves in iron-ore, limestone and quartzite), distinct fragility of various features in caves (speleothems, rock projections, etc) and structural and lithological changes on the terrain between the blasting site and the caves make calculations related to explosive amount and blast design difficult. There is no established Peak Particle Velocity (PPV) criteria for caves, and thus, adaptations from international standards related to very sensitive structures (e.g. historical building or monuments of special value or significance) have been adopted, resulting in PPV between 5 – 15 mm/sec. Cave monitoring for physical integrity in Brazil initially involves a detailed characterization of zones more susceptible to breakdown, sometimes including joint aperture measurements and modelling. A second step deals with high resolution photograph monitoring according to Moura et al. (2013). A cave fragility zoning is thus established, allowing for the determination of the cave areas more favourable to collapse. Regular visits and repeated photographs in the same sites enable the determination of even minute changes in the cave configuration. In parallel, seismograph monitoring allows for control of the blasting intensity and correlations to possible cave damage. Results so far have showed that the propensity of cave collapse varies widely between caves and a similar blasting intensity can produce very distinct results depending on several cave and rock properties. A conservative approach must, therefore, be adopted in order to minimize cave damage.
References: Auler, A.S.; Piló, L.B. 2015. Caves and mining in Brazil: The dilemma of cave preservation within a mining context. In: Andreo B. et al (Eds). Hydrogeological and Environmental Investigations in Karst Systems. Springer, p. 487- 496. Moura, V.; Auler, A.S.; Leão, M.; Alt, L. 2013. Photographic and sediment monitoring procedures and initial results for a Brazilian iron ore cave. In: 20th National Cave and Karst Management Symposium, Carlsbad, p. 153-162.
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Current fault activity observed in caves of the Eastern Alps
Ivo Baroň1, Lukas Plan1, Bernhard Grasemann2, Ivanka Mitroviċ1,2, Josef Stemberk3
1 Karst and Cave Group, Natural History Museum, Burgring 7, 1030 Vienna, Austria, [email protected], [email protected] 2 Department of Geodynamics and Sedimentology, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria, [email protected], [email protected] 3 Institute of Rock Structure and Mechanics ASCR, V Holešovičkách 94/41, 182 09 Prague, Czech Republic, [email protected]
Within the framework of the FWF project “Speleotect” (2013-2017), we observe recent activity of the major fault systems of the Eastern Alps, related to the Neogene and Quaternary lateral extrusion of parts of the Eastern Alps towards the Pannonian Basin, such as the (1) Salzach-Ennstal- Mariazell-Puchberg (SEMP), (2) Mur-Mürz, (3) Periadriatic, (4) Lavanttal, and (5) Vienna Basin marginal faults. This lateral extrusion is coeval with north-south shortening of the collision realm between the Adriatic Plate and the Bohemian Massif (European Plate). Totally seven high-accuracy 3D crack-gauges TM71 with automated reading devices were installed in six selected karst caves with tectonic faults younger than the particular caves. The recorded micro-displacement events have been compared to known regional fault kinematics and to regional seismic activity (seismic data provided by the ZAMG). Already within the first year of observation, several micro displacement events were registered; these events sometimes revealed the same mechanisms as the geologically documented kinematics of the particular active faults, but in some cases performed completely opposite kinematics. These micro displacement events occurred in seismically rather quiet periods, however, usually about 1 – 10 days prior to local seismic events of different magnitudes (varying between ML 0.1 and 3.3) most probably related to regional elastic strain changes. Further, in some caves gravitational mass movements were recorded that accompanied the tectonic moments.
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Cave damage caused by neotectonics and earthquakes ̶ or not?
Arnfried Becker1 1 Max-Planck-Str. 6, D-76351 Linkenheim-Hochstetten, Germany; [email protected]
Damage of speleothems in caves may have different reasons. Most unlikely they are related to paleo-earthquakes or active tectonics, at least in intra-plate Central Europe. Usually, they are caused by flood events, particularly in Alpine caves during periods of high and long lasting rainfalls and snowmelt. Unpleasant is cave damage due to vandalism, accidentally caused by frequent and careless visits of caves (also by bears for instance!), digging for archaeological remains, blasting in nearby quarries or willful damage and smear of speleothems. Also creep of sediments and ice in caves causes damage of embedded speleothems. With regard to ice, cave damage may be difficult to recognize because ice melts and may disappear without a trace. Cave damage due to ice creep caused a lot of confusion in the speleo-science community because, at first glance, it looked like strong earthquakes could have been the reason for the damage seen. With the dating of speleothems it became clear that most of the broken speleothems are old, i.e. of Pleistocene age. Just in the periglacial regions of Central Europe ice formation in subcutaneous caves with only a few tenth of meters sedimentary coverage probably was a common phenomenon during the last ice-age. Careful mapping and observations of the cave damage features finally clarifies that most likely ice creep caused most of the cave damage seen in Central European caves. Finally, also erosion of sediments below speleothems and flowstones causes instabilities and damage in caves. Displacements along fractures and bedding planes may have endogenetic reasons, i.e. are an expression of tectonic deformation, or exogenetic reasons caused by slope instabilities. Caves are frequently located in a topographically exposed position. Slumping, sliding, toppling and ice-push at the base of a surface-glacier may cause all kinds of fracture and bedding plane displacements which are not an expression of active tectonics. Again, careful mapping and detailed observations may avoid misinterpretations. For the investigation of earthquake damage in caves a whole bunch of methods developed in paleoseismology can be used in addition to speleothem damage investigations, which are the investigation of co-seismic fault displacements, rockfalls and soft-sediment deformation features in unconsolidated cave deposits. Primarily controlled by the distance of the caves from the earthquake epicenter, the focal depth and, of course, the intensity/magnitude of the earthquake, it is also important to keep in mind the depth of caves and site effects with respect to earthquake damage. Subcutaneous caves or caves in an exposed topographic position may be much more severely hit by earthquake shaking than deeply buried caves. That means that even favourable caves with sensitive speleothems and cave deposits in the near-vicinity of the epicenter of a strong earthquake may not show any damage. In paleoseismology we talk about geological archives which may preserve information about past strong earthquakes. Of these the most important archives are fault-scarps, lake deposits, features related to slope instabilities and caves. Each archive has strengths and weaknesses, and, generally, archives are not evenly distributed in the surroundings of an earthquake epicenter. Thus, it is important to combine the observations from different archives to receive as much information as possible about the paleo-earthquake. We called this approach "integrated paleoseismology" wherein speleoseismology is a powerful and integral part.
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Dating speleo-seismites near the Dead Sea transform and the Carmel fault: clues to coupling of a plate boundary and its branch
Yael Braun1, Elisa Joy Kagan2, Miryam Bar-Matthews2, Avner Ayalon2 & Amotz Agnon3 1 Department of Marine Geo-Sciences, University of Haifa, 199 Aba Khoushy Ave. Mount Carmel, Haifa, Israel, [email protected] 2 Geological Survey of Israel, Malki St 10, Jerusalem, 95261, Israel, [email protected] 3 Institute of Earth Sciences, Hebrew University of Jerusalem, Jerusalem 91904, Israel, [email protected]
An analysis of two published earthquake archives from the prehistoric Holocene provides insight into the interaction between two sectors of the Dead Sea transform (DST) and its side branch - the Carmel fault (CF). The two sectors considered are the Dead Sea basin (DSB) and the Jordan Valley (JV). The archives are based on datable damaged cave deposits (speleoseismites). The first archive is based on a pair of caves in the Judean Hills, 40 km west of the DSB. The second archive is recovered from a cave in the city of Haifa adjacent to the CF. In order to identify possible patterns of interaction within the DSB-JV-CF fault system, we compare the seismic event ages obtained from the two study sites using the same proxy, namely speleoseismites. The two archive sites are potentially affected by the same fault system, yet separated by 110 km. A very strong seismo- tectonic event affecting the entire region would give same ages (to within dating uncertainty) at both archives. Separate, local events, from either sector would record separately in either archive. We compare results from these studies with on-fault and archaeological paleoseismic studies from the CF and the Jordan Valley. Nine pre-historical Holocene speleoseismites were identified in Denya Cave, Haifa, interpreted to represent two seismic events (4.8±0.8 ka and 10.4±0.7 ka). For the same time period six speleoseismites were identified at the Judean Hills caves (Soreq and Har-Tuv caves) and cluster to two events (~5 ka, 8.6 ka). Together with other paleoseismic studies from the CF and JV regions, temporal correlation between cave archives implies coupling between the main fault sectors (DSB, JV), and CF branch. Specifically, the event at ~5 ka, well-recorded at both the Haifa and Judean Hills caves, manifests coupling. However, the penultimate Haifa cave event at ~10.5 ka seems to be limited to the northern region, along with the JV. The ~5 ka event could signify a CF rupture or a very large JV-DSB event, as well as a seismic event on one of the faults which triggers an event on the others. Using a simplified model, we list possible earthquake scenarios in order to better understand the tectonic regime of the region. Uncertainties may prevent differentiation of close events, but quiescent intervals or clustered earthquake events, are resolved.
8 Advances in Active Tectonics and Speleotectonics 2015, Vienna, Austria
Active Tectonics in the Eastern Alps and Surroundings
Kurt Decker1
1 Department of Geodynamics and Sedimentology, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria, [email protected]
Seismologic, tectonic, geomorphological, geodetic, and paleoseismological data from key structures of the Eastern Alps such as the floor thrust of the orogenic wedge, the major extrusion-related wrench faults, the metamorphic Tauern dome, the Brenner detachment fault exhuming the Tauern dome, and faults in the European foreland are used to identify the main structures compensating active shortening across the Alpine orogen. Data indicate that shortening encompasses a combination of ductile stacking, backthrusting, and tectonic exhumation in the western and central parts of the Eastern Alps and Southern Alps, and the lateral escape of crustal wedges in the east. Active E- to NE-directed lateral escape of the Alpine units between major reactivated Miocene wrench faults is well constrained by seismotectonic and paleoseismological data from the Vienna Basin Transfer Fault (e.g., Decker et al., 2005; Hintersberger et al., 2014), the Salzach-Ennstal- Mariazell-Puchberg Fault (Plan et al., 2010), and the Lavanttal Fault (Popotnig & Decker, 2011). It can be shown that active kinematics and slip rates are broadly comparable to the Miocene ones. Lateral escape is particularly important for compensating shortening of the easternmost Alps where wedges move out of the convergence zone at velocities of about 1-2 millimeters per year. Active deformation in the western transect of the Eastern Alps seems to be related to ductile aseismic thickening below the Tauren dome and the continuous tectonic exhumation of the dome below the west-directed Brenner detachment (Reiter et al., 2005). Ductile stacking at depth apparently causes both, continuous folding of the surface structures determined from Pliocene and Quaternary brittle deformation structures, and the uplift of the metamorphic dome at 1.5 –2 mm/a as shown by precise levelling data and large-scale geomorphic features like the geometry of drainage systems. Seismicity patterns indicate that thickening at depth is linked to south-directed backthrusting of the Southern Alps rather than to active north-directed thrusting along the Alpine floor thrust. The present inactivity of the northern floor thrust is corroborated by late Pleistocene fluvial terraces overlying the frontal thrusts without offset (van Husen, 1971). Older Pleistocene terraces, however, show significant vertical offsets at the crossing of these thrust faults. The described scenario of backthrusting, ductile thickening of the central part of the orogen, surface uplift, and the changing activity of the north-directed floor thrust is tentatively compared with orogenic wedge models. Models encompass repeated switches from foreland-directed thrusting to stages of basal accretion and backthrusting, which are required for maintaining the taper of the wedge. Such switches may be reflected by the Quaternary deformation history of the Eastern Alps. The proposed model is indicative for a locked Alpine floor thrust and for a stress coupling between the Alpine orogenic wedge and the European foreland. Such coupling is corroborated by the orientation of the recent maximum compressive stresses in the Bohemian Massif and the reactivation of crustal-scale strike-slip faults under N-S to NNW-SSE-directed compression there. Active faults in the Bohemian Massif include the East Sudeten Fault (Štěpančíková et al., 2010), the Diendorf-Cebin Fault (Roštínský et al., 2013), and the Hluboká Fault (Popotnig et al., 2013; Porpacy et al., 2014).
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References Decker, K., Peresson, H., & Hinsch, R., 2005. Active tectonics and Quaternary basin formation along the Vienna Basin Transform fault. Quaternary Sci. Rev., 24, 307-322. Hintersberger, E., Decker, K., Lüthgens, C., Fiebieg, M., 2014. Geological evidence for earthquakes close to the destroyed Roman city of Carnuntum. Schriftenreihe der der Deutschen Gesellschaft für Geowissenschaften, 85: 443. Plan, L., Grasemann, B., Spötl, C., Decker, K., Boch, R. & Kramers, J., 2010. Neotectonic extrusion of the Eastern Alps: Constraints from U/Th dating of tectonically damaged speleothems. Geology, 38, 483-486. Popotnig, A. & Decker, K., 2011. The kinematic evolution and tectonic geomorphology of the active Lavanttal Fault System, Austria. Geophysical Research Abstracts, 13, EGU2011-9818 Popotnig, A., Tschegg, D. & Decker, K., 2013. Morphometric analysis of a reactivated Variscan fault in southern Bohemian Massif (Budějovice basin, Czech Republic). Geomorphology, 197, 108-122. Porpaczy, C., Popotnig, A., Tschegg, D., Decker, K., 2014. Tectonic evolution of the Hluboká fault in southern Bohemia and ist implication for the formation of the Budejovice basin. Schriftenreihe der der Deutschen Gesellschaft für Geowissenschaften, 85: 447. Reiter, F., Lenhardt, W. & Brandner, R., 2005. Indications for activity oft he Brenner normal fault zone (Tyrol, Ausrtria) from seismological and GPS data. AJES 97: 16-23. Roštínský, P., Pospíšil, L. & Švábenský, O., 2013. Recent geodynamic and geomorphological analyses of the Diendorf–Čebín Tectonic Zone, Czech Republic. Tectonophysics, 599: 45-66. Štěpančíková, P., Hók, J., Nývlt, D., Dohnal, J., Sýkorová, I. & Stemberk, J., 2010. Active tectonics research using trenching technique on the south-eastern section of the Sudetic Marginal Fault (NE Bohemian Massif, central Europe). Tectonophysics, 485: 269-282. Van Husen, D., 1971. Zum Quartär des unteren Ennstales von Großraming bis zur Donau. Verh. Geol. B.-A., 1971/3, 511-521.
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Tectonic inception and the one-eighth relationship that constrains deglacial neotectonism and cave development in most Caledonide marbles
Trevor Faulkner1
1 Limestone Research Group, Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK. Email: [email protected]
The repeatedly-glaciated 40,000km2 region of central Scandinavia has over 1000 individual marble outcrops that contain nearly 1000 recorded karst caves. The metamorphic grade of the marble stripe karst bedrock varies up to amphibolite facies, giving it negligible primary porosity, in complete contrast to the setting for most caves in sedimentary limestones. Allied to this is the fine-scale foliation and consequent lack of bedding-plane partings. Indeed, the foliation is commonly vertical in the western part of the study area, where sub-horizontal openings are along joints or other fractures. The deepest cave is only 180m deep, despite marble outcrop vertical ranges reaching over 900m. Caves tend to cluster together and are positioned randomly in a vertical dimension, whilst commonly remaining within 50m of the overlying surface. Additionally, despite some marble outcrops being several tens of kilometres in length, there are no regional scale caves, and karst hydrological system distances are invariably shorter than 3.5km. The mean cave length and depth are only 85m and 9m. Because these caves are relatively short and epigean and there is a complete absence of long, hypogean, cave systems, speleogenesis by the (chemical) inception horizon hypothesis is unlikely. A tectonic inception model proposes that it is only open fracture routes that could provide the opportunity for dissolution and enlargement into cave passages in the Caledonide marbles. It is hypothesised that the dimensions of these fractures are related to the magnitude, and perhaps to the frequency, of local earthquakes and commonly-small neotectonic movements. These arose mainly from the isostatic rebound that accompanied deglaciation at the end of each major Pleistocene glaciation. The openings formed along inception surfaces between the limestone and adjacent aquicludes and at inception fractures that are entirely within the limestone and are commonly (though not universally) parallel to, or orthogonal to, the foliation. The model builds on reports of a ‘partially detached’ thin upper crustal layer in similar settings in Scotland. It is supported by observations of later neotectonic movements at the centimetre scale, as indicated by sharp edges and slickensides in most relict cave passages and sporadically on the surface. The present maximum subsurface cave distance (i.e. the distance of a passage to the nearest land surface) is commonly less than one-eighth of the depth of the local glaciated valley. This probably also equals the depth of the ‘partially detached’ layer. Fracture generation was thus likely related to the scale of isostatic uplift. That would partly determine the magnitude of seismicity caused by the differential pressure change and differential uplift that occurred along valley walls as each major Pleistocene icesheet margin receded from west to east. The maximum one-eighth relationship is also maintained in other Caledonide marble terranes in Scandinavia (except in northern Norway, where longer-range tectonic movements may apply), Scotland, Ireland and New England (USA). This suggests that many of the caves in these areas were formed by similar processes.
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Constraints on Long-Term Seismic Hazard From Vulnerable Stalagmites
Katalin Gribovszki 1,2, Götz Bokelmann1, Péter Mónus2, Károly Kovács2, Pavel Konečný3, Markéta Lednická3, Erika Hegymegi2 & Attila Novák2 1 Department of Meteorology and Geophysics, University of Vienna, A-1091 Vienna, Althanstrasse 14. (UZA II), Austria, [email protected] 2 Geodetic and Geophysical Institute, Research Centre for Astronomy and Earth Science, Hungarian Academy of Sciences, H-9400 Sopron, Csatkai E. utca 6-8., Hungary, monus@seismology.hu 3 Institute of Geonics, Academy of Sciences of the Czech Republic, Studentská 1768, 70800 Ostrava-Poruba, Czech Republic, [email protected]
Earthquakes hit urban centers in Europe infrequently, but occasionally with disastrous effects. This raises the important issue for society, how to react to the natural hazard: potential damages are huge, and infrastructure costs for addressing these hazards are huge as well. Obtaining an unbiased view of seismic hazard (and risk) is very important therefore. In principle, the best way to test Probabilistic Seismic Hazard Assessments (PSHA) is to compare with observations that are entirely independent of the procedure used to produce the PSHA models. Arguably, the most valuable information in this context should be information on long-term hazard, namely maximum intensities (or magnitudes) occurring over time intervals that are at least as long as a seismic cycle. Such information would be very valuable, even if it concerned only a single site. Long-term information can in principle be gained from intact stalagmites in natural caves. These have survived all earthquakes that have occurred, over thousands of years - depending on the age of the stalagmite. Their “survival” requires that the horizontal ground acceleration (HGA) has never exceeded a certain critical value within that period. We are focusing here on a case study in the Little Carpathians in Slovakia. A specially shaped (candle stick style: high, slim and more or less cylindrical form), intact and vulnerable, 4 m high stalagmite (IVSTM) in Plavecká priepast cave has been examined in 2013 and 2014. This IVSTM is suitable for estimating the upper limit for HGA generated by pre-historic earthquake. We determined by in-situ, non-destructive measurements the natural frequency and the harmonic oscillations of IVSTM, and in geo-mechanical laboratory the material properties (the density, the Young’s modulus and the tensile failure stress) of broken speleothem specimens have been measured. Based on the laboratory measurements and a simple mechanical model, the theoretical natural frequency (f0), the harmonic oscillations (f1, f2) and the HGA values resulting in failure (ag) have been calculated for IVSTM. The critical HGA level determined by this technique can be caused even by a low or moderate size earthquake.The age and the growth rate of one column in the Plavecka priepast cave was determined by taking core samples from two different heights. The interpretation of IVSTM from Plavecká priepast cave gives critical HGA values for different times in the past, therefore curves of critical HGA backward into the past have been constructed, for the surface and for the cave. This technique can yield important new constraints on seismic hazard, as geological structures close to Plavecká priepast cave did not generate strong paleoearthquakes in the last few thousand years, which would have produced HGA larger than the upper acceleration threshold that we determine from the IVSTM. Therefore we compared the effect of the Carnuntum event (350 AD), the Markgrafneusiedler event (2500 BP) and the Jókő (Dobra Voda) earthquake (10.01.1906) and the PGA value determined by PSHA calculation (SHARE Map) to the upper limit of the horizontal ground motion calculated from the IVSTM.
12 Advances in Active Tectonics and Speleotectonics 2015, Vienna, Austria
Fault linkage model of strike-slip and normal faults in the Vienna Basin (Austria) based on paleoseismological constraints
Esther Hintersberger1, Kurt Decker2, Johanna Lomax3, Markus Fiebig4 & Christopher Lüthgens5
1 Geologische Bundesanstalt (GBA), Neulinggasse 38, 1030 Vienna, Austria, [email protected] 2 University of Vienna, Althanstrasse 14, 1090 Vienna, Austria, [email protected] 3 Justus-Liebig-University Gießen, Senckenbergstraße 1,35390 Gießen,Germany, [email protected] 4 BOKU Vienna, Peter-Jordan-Strasse , 1190 Vienna, Austria, [email protected] 5 BOKU Vienna, Peter-Jordan-Strasse , 1190 Vienna, Austria, [email protected]
The interaction and kinematic linkage of single faults within a fault system is an important issue for estimating the seismic potential of the fault system. Faults can be either linked directly by merging in greater depths or by lateral growth or indirectly by influencing each other by stress loading and unloading due to earthquakes. The Vienna Basin in Central Europe between the Alps and the Carpathians is formed by a transtentional fault system consisting of a main strike-slip fault, which delimits the basin towards the east, and from which six secondary splay normal faults branch out and cross the entire basin. They seem to be geometrically linked with the main NNE-SSW striking left-lateral strike-slip Vienna Basin Transfer Fault (VBTF) via an E-dipping detachment, the Alpine thrust fault. Moderate seismicity (Imax/Mmax = 8-9/5.7) is focused along the southern and northern tips of the VBTF, whereas there are almost no earthquake records for the central Lassee segment and the splay normal faults during the last ~ 500 years. Geological and morphological data, however, document Quaternary movement at very slow vertical velocities of < 0.1 mm/a for the normal faults and at horizontal velocity of 1-2 mm/a for the VBTF. The question therefore is if and how strongly the normal faults within the Vienna Basin are linked kinematically to the VBFT. Is there any kinematic and geometric triggering or is the linkage based on mere stress transfer? In order to address this question, the number of large earthquakes along each fault, the amount of displacement during single earthquakes as well as the recurrence intervals for each fault are key parameters. Therefore, we did paleoseismological investigations at the Lassee segment of the VBFT as well as along one of the splay normal faults (Markgrafneusiedl Fault, MF). Correlation between three paleoseismological trenches across the MF revealed evidence for 5-6 major surface- breaking events during the last ~120 ka that cut and offset gravels of a Pleistocene terrace of the Danube in the footwall of the fault. Displacement estimates based on colluvial wedges and displaced layers lead to magnitude estimates ranging between Mw = 6.3 and Mw = 7.0. In sum, the recurrence interval of severe earthquakes with magnitudes > 6 at the MF is determined to 20-30 ka. First trenching results along the VBTF show the fault within the trench dissecting the same Pleistocene Danube terrace. Based on displaced layers, tension cracks and colluvial wedges, at least 3 major earthquakes since ~ 90 ka can be determined, with the most recent one occurring after 40 ka. We then combine the paleoseismological results with Quaternary slip rates derived from geomorphic and geological constraints. Thus, we can show that our data supports the hypothesis of a strongly linked fault system with the VBTF as the main driving force.
13 Advances in Active Tectonics and Speleotectonics 2015, Vienna, Austria
Database of active faults in Slovenia
Petra Jamšek Rupnik1, Jure Atanackov1, Jernej Jež1, Blaž Milanič1, Bogomir Celarc1, Matevž Novak1, Anže Markelj1 & Miloš Bavec1
1 Geological Survey of Slovenia, Dimičeva ul. 14, 1000 Ljubljana, Slovenia, [email protected]
The territory of Slovenia is subjected to moderate seismic activity resulting from faulting at the contact zone between the Adriatic microplate and the European plate (e.g. Poljak et al., 2000). Several active fault zones exist in the area: a) South Alpine thrust zone, b) Istria-Friuli thrust zone, c) Dinaric strike-slip fault zone, d) Periadriatic strike-slip fault zone, e) Sava Folds (and thrusts) zone, and f) Zagreb Mid-Hungarian shear zone (Placer et al., 2010; Poljak et al., 2000). Despite the moderate seismic activity and the presence of several damaging to devastating historical earthquakes (M 6.8 Idrija 1511, M 6.4 Villach 1348, M 6.1 Ljubljana 1895, M 5.9 Villach 1690, M 5.7 Brežice 1917, M 5.7 Bovec 1998), active faults in that area have not been systematically mapped and parametrized in the past. To assess the earthquake hazard geological data on active faulting in addition to recent and historical seismological data (which reaches only about 1000 years back at most) has to be considered. Given the comparatively moderate rate of tectonic and seismic activity, the seismological data do not sufficiently reflect the earthquake hazard in the area. Therefore, to better assess the earthquake hazard, a catalogue of active faults of Slovenia is warranted. Active faults with surface traces of ≥ 5 km length were systematically identified and parametrized into a catalogue that will serve as an input for seismic hazard assessment. The map of active and potentially active faults of Slovenia results from compilation and critical synthesis of available geologic, paleoseismic, geodynamic, geophysical, geodetic and seismological data. Using the structure of the SHARE database of seismic sources (Basili et al., 2013), each fault and its individual segments were described with: fault name, type, strike, dip, rake, depth, length, width, area, segmentation type, slip rate and possible maximum earthquake magnitude. The quality and origin of each estimated parameter was also designated. Currently, the catalogue contains nearly 50 faults and 120 segments in the western half of Slovenia (Atanackov et al., 2014) and the database will be complete in the current year.
References: Atanackov, J., Bavec, M., Celarc, B., Jamšek Rupnik, P., Jež, J., Novak, M., Milanič, B. 2014. Seizmotektonska parametrizacija aktivnih prelomov Slovenije = Seismotectonic parametrization of active faults of Slovenia. Ljubljana, Geological survey of Slovenia: 74 p., 4 suppl. Basili, R., Kastelic, V., Demircioglu, M. B., Garcia Moreno, D., Nemser, E. S., Petricca, P., Sboras, S. P., Besana-Ostman, G. M., Cabral, J., Camelbeeck, T., Caputo, R., Danciu, L., Domac, H., Fonseca, J., García- Mayordomo, J., Giardini, D., Glavatovic, B., Gulen, L., Ince, Y., Pavlides, S., Sesetyan, K., Tarabusi, G., Tiberti, M. M., Utkucu, M., Valensise, G., Vanneste, K., Vilanova, S., Wössner., J. 2013. The European Database of Seismogenic Faults (EDSF) compiled in the framework of the Project SHARE. http://diss.rm.ingv.it/share-edsf/ Placer, L., Vrabec, M., Celarc, B. 2010. The bases for understanding of the NW Dinarides and Istria Peninsula tectonics. Geologija 53, 1: 55–86. Poljak, M., Živčić, M., Zupančič, P. 2000. The seismotectonic characteristics of Slovenia. Pure and Applied Geophysics 157, 1–2: 37–55.
14 Advances in Active Tectonics and Speleotectonics 2015, Vienna, Austria
Soreq Caves: a 200,000 year-long dated speleo-seismite earthquake archive
Elisa Kagan1, Miryam Bar-Matthews1, Avner Ayalon1, Yael Braun2, Amotz Agnon3
1 Geological Survey of Israel, 30 Malkhe Israel St. Jerusalem, 95501, Israel, [email protected], [email protected], [email protected] 2 The Leon H. Charney School of Marine Sciences, University of Haifa, 199 Aba Khoushy Ave., Mount Carmel, Haifa 3498838, Israel, [email protected] 3 The Hebrew University of Jerusalem, The Fredy & Nadine Herrmann Institute of Earth Sciences, Givat Ram, Jerusalem 91904, Israel, [email protected]
Sub-recent Quaternary formations have been used for studying paleo-earthquake behaviour. Such sedimentary deposits are not always available in all places where large earthquakes have struck. Cave deposits (e.g. speleothems) have been considered as a potential target for late Quaternary paleoseismic studies. Speleothems can provide precise U-Th ages in high-resolution. Caves provide a closed environment protected from most erosive activity. We have compiled a long-term (~200 kyr) paleoseismic record at the Soreq and nearby Har-Tuv caves, near Jerusalem. The study caves, located 40 km west of the Dead Sea Transform, record earthquake damage from Dead Sea Transform ruptures and, possibly, smaller local intraplate events. The evidence in the study caves includes collapsed ceiling blocks, severed stalagmites, collapsed stalactites, collapsed columns, changes in growth axis, and cracks and faults in cave walls. Many of these features are covered by post-damage regrowth. Non-seismic sources of collapse, such as ice-movements, ground subsidence, river flow, and cave- bears, problematic elsewhere, were considered and refuted. Neither ice cover, nor perma-frost, has occurred in this region during the investigated period. Ground subsidence does not pose a problem since the cave floors are solid carbonate rock. No evidence for river flow exists. The caves have only non-natural recent openings; therefore pre-1960’s animal or anthropogenic effects are not a possibility. More than fifty-five seismites were sampled and dated. For the past 200 millennia these collapses are grouped into 26 events, interpreted to be earthquakes. Seismite ages appear to be spatially distributed randomly throughout the cave. Some of the different types of cave damage occurred at specific times in the past 200 millennia. These two observations support seismogenic origin of damage. Of the 26 events, there are 21 collapse events that are defined by more than one seismite or by both pre and post ages. Seven quiescence intervals are discernible, with no pre or post damage ages during that time. The 26 events from 200 ka to present lead to a mean recurrence interval of approximately 6.8 ky, or 6.6-6.8 ky, depending on the time period chosen for investigation with an aperiodicity value of 0.7, lending to quasi-periodic behavior. If only the 21 events dated by more than one age are used, the recurrence interval increases to 7.8-8.6 ky, and the aperiodicity values change slightly to 0.5-0.6 with the quasi-periodic behavior persisting. This recurrence interval is argued to be much longer than that interpreted from the Dead Sea lake seismite archive earthquake history due to filtering out of the smaller earthquakes in the cave environment and the somewhat more distant location.
15 Advances in Active Tectonics and Speleotectonics 2015, Vienna, Austria
The seismothems of the Emine-Bair-Khosar Cave (Crimea)
Iuliia Kalush 1, Bogdan Ridush 1
1 Chernivtsi “Yurii Fed’kovych” National University, str. Kotsubynskogo 2, 58012, Chernivtsi, Ukraine. E-mail: [email protected]
The Crimean Mountains is one of the most active seismic regions in Ukraine. There is such geological evidence about seismicity as statistical data about earthquakes and paleoseismic dislocations, i.e. geomorphological consequences of the ancient earthquakes. However, we consider it important to identify and investigate seismothems, i.e. seismogenic structures in karst cavities (Delaby, 2001). Karst caves in Crimea possess a great potential to investigation the tectonic and paleoseismic processes particularly. Earthquakes lead to the formation of hollows, a collapse of an intermediate floor, destruction of large stalactites, stalagmites and columns in the caves. Totally, the seismothems were observed in 29 karst caves, including the Emine-Bair-Khosar Cave, where we conducted our investigation. The Emine-Bair-Khosar Cave is one of the largest caves in Crimea, situated on the plateau Chatyrdag. It is 1630 m long and 125 m deep; the volume is 160 500 m3 (Vremir Ridush, 2008). Plateau Chatyrdag is a part of the Main Ridge of the Crimean Mountains and belongs to the seismic zone with Mw=5-6 respectively to the seismic zoning of the Crimean peninsula. The examined seismothems are situated in the middle part of the cave, in the Idol’s Chamber. Among the number of fragments, four large flowstone boulders attracted our attention. They are located on the northern ledge wall of the hall, at 10-15 m above the bottom (fig. 1).
Fig. 1. A – Location of seismothems on the wall terrace in the Idol’s Chamber; B – The seismothem N 1.
They are the fragments of old massive stalactites broken off the powerful seismic shock and launched to the terrace-ledge on the wall accordingly to the trajectory of the seismic wave. We have measured the size of the stalactites, distance from the boulders to their former position, and vectors of stalactites displacement. The largest of fragments (N1, fig.1) with the size of 1.68 m in diameter and 1.4 m long, was launched at more than 2 m horizontally from its initial position. Visual observation and instrumental measurement of the seismothems allowed us to set different directions and sequence falling of these boulders. It indicates that the collapses were caused by at least two seismic events (shocks) of approximately identical intensity and magnitude, but with
16 Advances in Active Tectonics and Speleotectonics 2015, Vienna, Austria different epicenters of earthquakes. Such seismothems should be formed only during seismic shocks Mw> 7, located in the southern part of the peninsula with a period of recurrence over 1,000 years. The dating of secondary formations on these seismothems will set the period of the collapse formation and frequency of the seismic shocks. Seismothems of the Emine-Bair-Khosar Cave can be used in paleoseismological method for determining of tectonic activity and seismic zoning of Crimea.
17 Advances in Active Tectonics and Speleotectonics 2015, Vienna, Austria
Sediment burial dating as a tool in active tectonics research - OSL and cosmogenic nuclides
Christopher Lüthgens1, Sandra Braumann1, Stephanie Neuhuber1,Eike Rades1, & Markus Fiebig 1
1 Institute of Applied Geology, University of Natural Resources and Life Sciences (BOKU), Vienna, Peter-Jordan- Straße 70, 1190 Vienna, Austria, [email protected]; [email protected]; [email protected]; [email protected]; [email protected]
Deciphering the complex interactions of geomorphological and tectonic process networks requires accurate chronological reconstruction of documented events. Valuable archives of such processes are provided by the geomorphological landscape record and sedimentary deposits. A broad portfolio of numerical dating techniques is nowadays at hand to establish such chronologies. This presentation will introduce the basic principles of two of the most promising sediment burial dating approaches using either optically stimulated luminescence (OSL) signals, or cosmogenic nuclides (26Al and 10Be). Luminescence dating techniques rely on the nature of non-conductive minerals such as quartz or feldspar that store measurable radiation damage within their crystal lattices. Ionizing radiation caused by the decay of naturally occurring radionuclides as well as cosmogenic radiation lead to the build-up of a latent luminescence signal. This signal is preserved as long as the crystals remain sealed from daylight (burial), as soon as they are exposed to daylight (transport) the signal is zeroed (bleached). Because the number of trapped charge carriers correlates with the stored energy per mass unit, the mineral grains function as natural dosimeters. The intensity of the latent luminescence signal measured in the laboratory corresponds to the amount of energy stored within the crystal. Once the rate of stored energy per time is known, it is possible to calculate the time elapsed since the crystal was last exposed to daylight. Burial age dating using 26A and 10Be is a method to date the sedimentation age of Plio- and Pleistocene sediment samples. Both radiogenic isotopes are generated by cosmic ray interaction with e.g. silicon or oxygen. The ratio of produced 26Al and 10Be is constant over time and lies at ~6.6 at the surface. Once the sample is shut off from cosmic ray interaction by subsequent burial both isotopes start to decay and their ratio changes to lower values. Sample preparation for cosmogenic nuclide measurement involves physical and chemical cleaning and purification of quartz. The main goal is clean quartz where Al and Be are extracted from within the crystal lattice by acid digestion and precipitated using ion exchange columns and selective precipitation techniques. Chances and challenges of the individual approaches will be discussed as well as the potential of combining both methods. This will be illustrated against the background of the results of an initial case study from the Vienna basin. Here we sampled a fluvial, mainly conglomeratic terrace sequence close to Markgrafneusiedl. First results will be presented at the workshop.
18 Advances in Active Tectonics and Speleotectonics 2015, Vienna, Austria
Non karst caves of the Polish Flysch Carpathians and their connection with stages of mass movement formation: tectonic constrains, dating and classification
Włodzimierz Margielewski1, Jan Urban1, Czesław Szura2
1Institute of Nature Conservation, Polish Academy of Sciences, A. Mickiewicza Ave 33, 31-120 Kraków, Poland. 2Association for the Caves’ Conservation “Malinka Group”, Wisła, Poland
Non-karst caves (called also „pseudokarst caves”) commonly occur in the flysch massifs of the Outer Carpathians. Within Polish Outer Carpathians more than 1300 caves of the total length about 23.5 km have been recorded up till now (Klassek, Mleczek, 2014). Most these caves are genetically connected with gravitational mass movements, being formed during the initial stages of slope failures (as extensional cracks) as well as within the landslide landforms, as continuations of landslide head scarps within the rock substratum or within the landslide bodies and packet colluvia (Margielewski, Urban, 2003, 2005; Margielewski 2006; Lenart et al., 2014). The caves formed in the initial stage of slope failure develop owing to gradual unloading of shearing stresses in rock massifs, which are affected by external factors disturbing the slope equilibrium such as earthquakes, erosional undercuts, overloading of slopes by precipitation etc. Opening and widening of cracks owing to the relaxation of these stresses take place along natural discontinuity surfaces, joints and faults, existing within rock massifs up to the exceeding of shearing stress limits (Margielewski, Urban, 2003). Exceeding of these limits causes that the disintegrated fragment of rock massif, separated from the host massif with crack system is gravitationally moved up to the moment of the stabilisation of new dynamic slope equilibrium. The phenomenon of rock massif disintegration obviously occurs also during the main phase of landslide formation and subsequent slope deformations, producing underground cavities, i.e. caves, if they are accessible for people (Margielewski, Urban, 2005, Margielewski, 2006; Baroň et al., 2014; Lenart et al., 2014). Development and subsequent widening of extension cracks (caves) are related to two geomechanic phenomena (processes): dilation (dilatation) and dilatancy. The dilation is defined as a change in volume but not in shape of solid matter such as e.g. rock massif. The result of this process is disintegration of rock massif along gradually widened cracks (caves) into separated segments which are stable up to the moment of exceeding of marginal stress. Phenomenon of dilatancy consists in growth of matter (rock) volume and change in its shape. This process developing in granular medium is called granular dilatancy, while the process of volume increase due to the crevice propagation and widening (often within the zone of rock massif shearing destruction) is called fissure dilatancy (Kranz, Scholz, 1977; Kwaśniewski, 1986). The systems of cracks (caves, cave passages) developed along natural discontinuities within and close to the sliding zones of landslides are usually generated by this second type of dilatancy (strictly: fissure macrodilatancy) (Margielewski et al. 2007). The hitherto used classifications of non-karst caves were referred to their shape and genesis as e.g. categorisation proposed by Viték (1983), who distinguished two types of gravitationally induced caves: crevice-type and talus-type; or were based on the character of movements of rock massifs (respectively to the classification of mass movements by Dikau et al. 1996), as proposal of Lenart et al. (2014) who listed V, H and A-type of cave passages. The proposed new classification is based on two criteria: morphogenetic and geomechanic (Urban, Margielewski, 2013). The morphogenetic criterion regards the relation between the stage of slope evolution (failure) and crevice/cave development. Using this criterion the following types were distinguished (Urban, Margielewski, 2013): a) Initial caves, whose formation precedes significant mass movements; most crevice type caves in Viték’s (1983) categorisation belong to this type.
19 Advances in Active Tectonics and Speleotectonics 2015, Vienna, Austria b) Subsequent (epigenetic) caves, forming within the landslide bodies or packet colluvia; according to Viték’s (1983) classification, they represent mainly talus-type caves, however some crevice-type ones belong to this group, too. c) Intermediate caves, which occur in the cutting surface between the in situ massif and landslide bodies; their upslope walls are usually continuations of landslide main scarps. d) Multi-stage caves, formed in both, initial and main phases of slope failures. The geomechanic criterion regards the process/mechanism responsible for the cave formation. In this categorisation the following cave types are listed (Urban, Margielewski, 2013): a) Dilational caves, formed owing to the dilation process; this group is represented by crevices widened both before the landslide formation (as initial caves) and during the significant slope failure (landslide formation); in the Viték’s (1983) classification they represent the crevice-type caves. b) Dilatancy caves, formed owing to the fissure macrodilatancy sensu Kwaśniewski (1986), are located usually within the slide zones of landslides, along the boundary between the untouched substratum and disintegrated, gravitationally moved fragment of massif. c) Boulder caves, produced by chaotic movements of rock blocks usually within the colluvia and in Viték’s (1983) classification representing the talus type caves (see also: Bella, Gaál, 2010). d) Complex caves, combining features of listed above caves. The presented above classification makes possible clear and unequivocal determination of nature of caves genetically related to gravitational processes in mountain slopes. On the basis of the radiocarbon, U-series datings and palynological analysis of carbonate speleothems found in several caves as well as OSL datings of the cave sediments the attempts to determine the moment of opening and modifications of the cracks (cavities) have been conducted. The study indicates that owing to minute uranium content and large amount of detrital thorium the U-series method seemed to be useless for this purpose. The U-series datings were overestimated, much older than the ages of the same samples obtained by the radiocarbon method, which are, in turn, confirmed by palynological data (Urban et al., 2015). Using the radiocarbon method (regarding the reservoir effect) the beginning of the speleothem formation were dated. Moreover, the ages of changes from the concentric to the de-concentric speleothem growth (curvatures of growth axes), which were related to the rotation of rock blocks within the caves, i.e. rejuvenation of slope failures, were determined. These datings proved that the oldest studied caves were formed in the Late Glacial (Jaskinia Miecharska Cave in the Beskid Śląski Mts., Jaskinia Słowiańska-Drwali Cave in the Beskid Niski Mts.) (Urban et al., 2015). The beginning of the speleothem formation or their de-concentric growth was also connected with the climatic phases of high precipitation in the Late Glacial and the Holocene, during which the intensification of mass movements in the Polish and Czech parts of the Carpathians was recorded (Margielewski, 2006; Starkel et al., 2013; Pánek et al., 2013). The research was performed within a scientific project no. NCN NN306 522 738 granted by the Polish Ministry of Education and Science in 2010-2015.
References: Baroň, I., Bečkovský, D., Miča, L., 2014. Application of infrared thermography for mapping open fractures in deep- seated rockslides and unstable cliffs. Landslides, 11: 15-27. Bella, P., Gaál, L., 2010. Boulder caves – terminology and genetic types. Aragonit, 15, 1: 3-10. Dikau, R., Brunsden, D., Schrott, L. & Ibsen, M. L. (Eds.), 1996. Landslide recognition. Identification, Movement and Causes. J. Willey et Sons, pp. 1- 251. Klassek, G., Mleczek, T., 2014. Exploration and investigation of the cave in the Polish Flysch Carpathians (September 2012 - August 2014) (in Polish). In: Stefaniak, K., Ratajczak, U., Wróblewski, W., (Eds.), Materiały 48. Sympozjum Speleologicznego, Kletno 16-19.10.2014. Sekcja Speleologiczna PTP im. Kopernika, Kraków: 76 - 80. Kranz, R.L., Scholz, C.H., 1977. Critical dilatant volume of rocks at the onset of Tertiary creep. J. Geophys. Res. 82: 4893-4898. Kwaśniewski, S., 1986. Dylatancja jako zwiastun zniszczenia skały. Część 2. Mechanizm zjawisk poprzedzających zniszczenie (in Polish). Przegląd Górniczy, 42: 184-190.
20 Advances in Active Tectonics and Speleotectonics 2015, Vienna, Austria
Lenart, J., Panek, T., Dusek, R., 2014. Genesis, types and evolution of crevice-type caves in the flysch belt of the Carpathians. Geomorphology, 204: 459-476. Margielewski, W., 2006. Structural control and types of movements of rock mass in anisotropic rocks: case studies in the Polish Flysch Carpathians. Geomorphology, 77(1-2): 47-68. Margielewski, W., Urban, J., 2003. Crevice-type caves as initial forms of rock landslide development in the Flysch Carpathians. Geomorphology, 54: 325-338. Margielewski, W., Urban, J., 2005. Pre-existing tectonic discontinuities in the rocky massifs as initial forms of deep- seated mass movement development: case studies of selected deep crevice-type caves in the Polish Flysch Carpathians. In: Senneset, K., Flaate, K., Larsen, J. O., (Eds). Landslides and Avalanches, ICFL 2005 Norway. A. A. Balkema publ., London, pp. 249-256., Margielewski, W., Urban, J., Szura, C., 2007. Jaskinia Miecharska Cave (Beskid Śląski Mts., Outer Carpathians): Case study of the crevice type cave developed on sliding surface. Nature Conservation, 63 (6): 57-68. Pánek, T., Smolková, V., Hradecký, J., Baroň, I., Šilhán, K., 2013. Holocene reactivations of catastrophic complex flow-like landslides in the Flysch Carpathians (Czech Republic/Slovakia). Quaternary Research, 80, 33-46 Starkel, L., Michczyńska, D., Krąpiec, M., Margielewski, W., Nalepka, D., Pazdur, A., 2013. Holocene chrono- climatostratigraphy of Polish territory. Geochronometria, 40 (1): 1- 21. Urban, J., Margielewski, W., 2013. Types of non-karst caves in Polish Outer Carpathians – historical review and perspectives. In: Filippi, M., Bosak, P., (Eds.), Proceedings of the 16th International Congress of Speleology, 21-18.07., Brno, vol. 3, pp. 314-319. Urban, J., Margielewski, W., Hercman, H., Žák, K, Zernitska, V., Pawlak, J., Schejbal-Chwastek, M., 2015. Dating speleothems in sandstone caves - methodological aspects and practical interpretation, Polish Outer Carpathians case study. Zeitschrift für Geomorphologie 59, Suppl. 1: 183-208. Viték, J., 1983. Classification of pseudokarst forms in Czechoslovakia. Intern. Journal of Speleology, 13: 1-18.
21 Advances in Active Tectonics and Speleotectonics 2015, Vienna, Austria
Active tectonics and hypogean caves: a view from the Apennines of Italy
Marco Menichetti1
1 Earth, Life and Environmental Department University of Urbino, Campus Scientifico, 61029 Urbino - Italy, [email protected]
Hypogene speleogenesis is related to rock corrosion driven by the upward flow of aggressive deep- seated fluids. As these fluids flow through the rock mass, they transport endogenic agents that cause chemical or/and physical rock corrosion. In a carbonate massif, the permeability of the rock mass is mainly conditioned by the tectonic structures consisting of faults and fractures. At the shallow crustal level, where the deformation is mainly brittle, the spatial geometries of the fracture system can be localized or distributed throughout the rock mass. In the shear zone, the fault-damage zone has a high heterogeneity with respect to fluid permeability, which is controlled mainly by the interconnections between existing discontinuities such as bedding, joints, faults etc., and by different mechanical proprieties of the surrounding rock mass. Pore fluid pressure plays an important role in determining the pathway for fluid migration. Infiltration of pressurised fluids in the rock mass could initially occur along pre-existing discontinuities, producing a range of differently oriented brittle structures that become progressively interlinked into a “structural mesh”. Thus, the resulting bulk structural permeability within the rock mass can be regarded as “self- generated” by the infiltrating fluids. Under different stress regimes (extensional, compressional and strike-slip), the geometry of the fracture zone and mesh structures manifests either as subvertical extensional “chimneys” or “fuzzy” extensional faults with an overall component of shear across the mesh. Evidence that such mesh structures are primarily fluid-driven comes from their location with respect to the karstic massifs, from the hypogenic cave patterns and morphological sizes (including 3D maze gallery geometries), from hydrothermal alteration and veining, which indicate their role as fluid conduits, and from the presence of mineralized extension veins indicative of local overpressuring. The rising of fluids through the crust is driven mainly by seismic activity (seismic pumping), hydrothermal circulation and related mechanisms. The release of deep fluids rich in CO2 or H2S into the faults and fractures in the carbonate rocks is very common during earthquake swarms with areas of active extensional or transtensional tectonic regimes. Veining and hydrothermal alteration associated with fault-rock assemblages in hypogenic karst systems provide some information on fluid involvement in hydrothermal systems and can be used to build preliminary models for the interaction of endogenic fluids with the karst system. Evidence for fluid interactions and involvement with karstic massifs at shallow crustal depths are common both in fossil and active hypogean caves. In a tectonically active region, such the Apennines of Italy, the main sources of H2S and CO2 in the active underground karst systems can be linked to different processes driven by endogenic fluid emissions. Regional crustal degassing seems to be the prevalent source for carbon dioxide in the karst massifs, with most being released into the groundwater. Hydrogen sulfide and methane oxidation, possibly mediated by bacterial activity, are other aggressiveness fluids sources in buried Cenozoic sediments.
22 Advances in Active Tectonics and Speleotectonics 2015, Vienna, Austria
The main phase of the Apennine chain uplift, related to cave development, took place within the Pleistocene in an extensional tectonic regime. The main structures that control the underground Apenninic karst morphology are a system of N-S trending faults and networks of conjugated joint sets distributed in a primary NE-SW and secondary NW-SE directions. In particular, the strike-slip N-S faults are related to the main galleries and rooms, and control the development of the larger underground passages, while the joint systems locally condition solutional passage morphologies.
23 Advances in Active Tectonics and Speleotectonics 2015, Vienna, Austria
Age of the allogenic quartz pebbles from Snežna jama, Huda luknja and Špehovka for implication of tectonic uplift Kamnik Alps and Karavanke, Slovenia
Philipp Häuselmann1, Andrej Mihevc2 & Markus Fiebig 3
1 Philipp Haeuselmann, Schweiz. Inst. für Speläologie und Karstforschung, c.p. 818, 2301 La Chaux-de-Fonds, Switzerland, [email protected] 2 Andrej Mihevc Karst Research Institute SRC SASU, Titov Trg 2, 6230 Postojna, Slovenia, [email protected] 3 Markus Fiebig, University of Natural Resources and Life Sciences, Peter Jordan-Str. 70; A-1190 Wien; Austria, [email protected]
Here we report on the burrial age dating of alogenic quartz pebles deposited in caves in in mountain groups of Kamnik Alps and Karavanke both part of the Southern Calcareous Alps. Snežna jama is 1.6 km long horizontal cave, situated in the slopes of the Raduha ridge (Velika Raduha, 2062 m a.s.l.). The cave entrance is on the south-western slope of the Raduha. The cave was formed by an allogenic river that had later filled it with siliciclastic sediments. Since deposition, tectonic activity caused uplift of the massif and cave became relict while Savinja River cut about 900 m deep valley since then. Fluvial sediments were deposited in the main gallery of the cave. A sample of the pebbles was taken and quarz grains were selected from the other material. Burial age of quartz pebbles in Snežna jama was 3.72 ±1.33 Ma. Result of the dating fits well with a complex magnetostratigraphic picture, which was obtained by the high-resolution palaeomagnetic research and and palaeontologic data. The Karavanke Mountains are mostly presented by narrow ridges that are lowering toward E. Deeply incised valleys mostly follow the main trend of the mountain, but some of the rivers, like Paka, cut across mountains forming deep antecedent valleys in limestone. Canyon of Paka was also formed by small rivers that have catchment area on Miocene conglomerates, to sink and flow into the canyon where the springs were. As the Paka was cutting down, following the uplift of the ridge, several caves were formed. Fluvial sediments, mostly pebbles can be found in all caves. Quartz pebbles from three profiles were analysed. In cave Huda luknja quartz pebbles were collected from two profiles at 550 m and 570 m. In cave Špehovka sample was taken at elevation 640 m. The ages of two samples in Huda luknja were similar; probably the sediment was from the same cave infill phase (2.39 ± 0.38 Ma at 550 m and 2.25 ± 0.25 Ma at 570 m. The infill from Špehovka cave (637 m) is significantly older, 3.49 ±0.40 Ma. The age dates provide grounds for a first relatively firm estimate of the long-term tectonic uplift rate between Velenje basin on S and Periadriatic lineament on N of the two caves.
24 Advances in Active Tectonics and Speleotectonics 2015, Vienna, Austria
Are we able to identify co-seismic deformation in caves? Comparative Study of naturally and experimentally sheared calcite speleothems
Ivanka Mitrovic1,2, Lukas Plan1, Bernhard Grasemann2, Ivo Baroň1
1 Department of Geodynamics and Sedimentology, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria, [email protected], [email protected] 2 Karst and Cave Group, Natural History Museum, Burgring 7, 1030 Vienna, Austria, [email protected], [email protected]
Calcite speleothems are reported to be suitable for investigating past tectonic activity of a region. Scratched speleothems found in Hirschgruben cave, Northern Calcareous Alps, were naturally deformed during a strike-slip fault movement that occurred between 118 ka and ca. 9 ka, due to activity of the SEMP (Salzach-Ennstal-Mariazell-Puchberg) fault system. This is a field evidence for active displacement along the SEMP fault and the recent lateral extrusion of the Eastern Alps towards the Pannonian Basin. In order to recreate a fault conditions mapped in the Hirschgruben cave, we sampled undeformed speleothems from the same cave, cut them into blocks and sheared using a rock deformation biaxial apparatus BRAVA at INGV Rome, keeping the calcite long growth axes perpendicular to the shearing direction. Microstructural analyses of our natural samples pose evidences for changing fault behavior, including both seismic slip and aseismic creep. To investigate possible mechanisms, we implemented series of high-resolution electron beam analytical techniques including scanning electron microscope, cathodoluminescence and electron backscattered diffraction. We aimed to distinguishing between seismic slip and aseismic creep, in order to understand the past and active tectonics and seismicity. This research is a part of Speleotect project (FWF - P25884 - N29) that investigates the active tectonics of Eastern Alps in caves and has an aim to update the paleoseismic record of the Eastern Alps for regional earthquake hazard assessment.
25 Advances in Active Tectonics and Speleotectonics 2015, Vienna, Austria
Recent evidences of Plio-quaternary tectonic activity in the Constantine Basin (North-East of Algeria)
Yahia Mohammedi1,2, Hamou Djellit1 & Hamidatou Mouloud1,3
1 Centre de Recherche en Astronomie, Astrophysique et Géophysique, Bp 63 Route de l’observatoire, Bouzarèah-Alger, Alegria, [email protected] 2 Faculté des sciences de la terres/Université des sciences et de la technologie Houari Boumediene, Bab ezzouar, Alger, 3 University 20 août 1955- Skikda, Algérie
The Constantine basin is an East-West Post thrust-sheet depression, formed mostly by lagoon, lacustrine and continental deposits. The strongest earthquake recorded in the eastern Tellian Atlas (northeast Algeria) since the beginning of instrumental seismology was located at the southern border of this basin (36,46N, 6,76E, depth = 10 km, M = 5.9, from NEIC). In this presentation, we show evidences of active tectonic that affect not only the southern border but also its northern part. Three approaches were adopted: (1) the Remote sensing approach by using LandSat8 images, EO- Ali and aerial photos of 1/40 000 images; (2) the Morphotectonic approach by using Digital Elevation Models (DEM). The third is a classic geologic mapping and structural analysis directly in the field. Two successive post-Pliocene tectonic phases have been identified: (1) The first is an extension EW generating normal faults striking N-S to NNE-SSW. Generally, these faults are located on the edge of old massifs. The faults of this event show evidences of recent activity (upper Quaternary). This event is probably a subsidence response in conjunction with the current uplifting of old massifs bordering the basin. (2) The second phase is compressive. This second event is expressed by a set of NE-SW to E- W reverse and transpressif structures like the senestral Aïn Smara active fault (west of Constantine) and the dextral Aïcha Debbar active fault (NE of Constantine). The geometrical kinematics characteristics of these faults were clarified during this work.
26 Advances in Active Tectonics and Speleotectonics 2015, Vienna, Austria
Speleotectonic constrains from the ‘Tripa tou Fournari’ cave, Thessaloniki, Greece (a preliminary report).
Christos Pennos1, Stein-Erik Lauritzen1, Charikleia Gkarlaouni2 & Yorgos Sotidiadis3
1 University of Bergen, Allégt. 41 N-5020, Bergen, Norway, [email protected] [email protected] 2 Aristotle University of Thessaloniki, Department of Geophysics, University Campus GR-54124 Thessaloniki, Greece, [email protected] 3 Gaia S.A. Meleton, Monastiriou 95, GR-5642 Thessaloniki, Greece, [email protected]
This work presents the preliminary results of our study concerning the speleogenetic processes that formed the "Tripa tou Fournari" Cave (TFC) and their relation to the active tectonic regime of the area. TFC is a small vertical cave found in the vicinity of an old marble quarry in near the city of Thessaloniki (N. Greece). The vertical depth of the cave is 18 m and its projected length is almost 20 m. The width of the cave passages varies from 50 cm to 10 cm. The TFC is located at a NW-SE narrow graben that is bounded to the south by Pefka- Asvestochori normal fault (PAf). A complex network composed of antithetic smaller faults has been mapped at the hanging wall of the basin where the cave is found. PAf is oriented in N120 steeply dipping to the north and it is thought to be the western continuation of the major Thessaloniki – Gerakarou rupture zone that is responsible for the 1978 earthquake event that struck the city of Thessaloniki (M≥6.0). We studied the meso-morphological characteristics of the cave as well as the micro morphology and the cave deposits. Our results suggest that the cave was created under vadose conditions. The breccia zone that was created due to fault activity allowed the solutions to move freely into this zone. These speleogenetic agents dissolved part of the breccia zone. Breccia dissolution and removal resulted on the void creation (i.e. cave) between the fault walls. At the same time the calcite that deposited on the cave walls holds inside part of the carbonate breccia (tectonothem). To delimitate the age of the tectonothem we date the matrix using Th/U dating techniques. This will enable us to determine the age of the cave formation and will provide constrains on the fault movement.
27 Advances in Active Tectonics and Speleotectonics 2015, Vienna, Austria
Relationship between CO2 content in fault caves and microseismicity
Raúl Pérez-López1,Magda Patyniak2, Sergio Sánchez-Moral3, Enrique Bañón4, Ana Manzanares4, Jorge L. Giner-Robles5, Pablo G. Silva6, Soledad Cuezva3, Julio López-Gutierrez1 & Miguel A. Rodríguez-Pascua1 1 IGME – Instituto Geológico y Minero de España. C/Ríos Rosas 23, Madrid 28003. SPAIN, [email protected] 2 University of Potsdam, Am Neuen Palais 10, House 9 14469 Potsdam, GERMANY, [email protected] 3 CSIC – Museo de Ciencias Naturales, Madrid. SPAIN, [email protected] 4 Espeleoclub RESALTES. Molina del Segura, SPAIN, [email protected] 5Universidad Autónoma de Madrid. Madrid, SPAIN, [email protected] 6 Universidad de Salamanca. Ávila, SPAIN, [email protected]
Caves developed in areas of active faulting are a good chance for monitoring gas and temperature changes in natural depths that are related to tectonic processes. The seismic activity of the south- eastern part of Spain is very high due to the tectonic setting. Evidence of paleoseismic activity has been reported by several authors (Silva et al., 1993, Rodriguez-Pascua et al., 2008, Ortuño et al., 2012, among others) as well as paleoseismic effects in caves (Pérez-López et al., 2009). The Benis Cave is the deepest and one of the best studied in this area with a depth of -320 m underneath the surface. It is a result of the intersection between a network of phreatic vertical tubes and a fault plane of normal character, what makes the setting notably. Therefore the topography and the decoration of the cave are clearly determined by the fault activity. Furthermore pop-corn pattern on the footwall-plane in this cave could be described as a new type of seismothem showing kinematics and geometry consistent with the movement of the hanging wall and the strain tensor determined by striation and instrumental earthquakes records. Besides structural effects, monitoring of temperature and CO2 in a timespan of two years have shown a positive correlation between microseismic activities (Mw 1.0 – 3.0, in a circumcircle of up to 60 km) and sharp variations in the gas concentration (Fig. 1). This work has been partially supported by the Spanish Project SISMOSIMA, CGL2013-47412-C2-2-P and INTERGEO CGL2013-47412-C2-1-P
Figure 1 Benis Cave - CO2 variations between two successive measurements for March 2015. Due to the accuracy of the measuring advice an error of ±30 ppm has to be taken into account, shown in light grey. The bullets indicate the earthquakes occurred during the measurement series, graduated by size and colour according to the magnitude and sorted by time off occurrence and distance from the cave.
References: Pérez-López et al., 2009, Speleoseismology and palaeoseismicity of Benis Cave (Murcia, SE Spain): coseismic effects of the 1999 Mula earthquake (mb 4.8). Geological Soc. of London SP 316 , 207-216. Ortuño et al., 2012. An exceptionally long paleoseismic record of a slow-moving fault: The Alhama de Murcia fault (Eastern Betic shear zone, Spain). Geol.l Soc. of America Bull. 124(9-10), 1474-1494 Silva et al., 1993, Landscape response to strike-slip faulting linked to collisional settings: Quaternary tectonics and basin formation in the Eastern Betics, Southeast Spain. Tectonophysics 224, 289-303 Rodriguez-Pascua et al., 2008, Recent seismogenic fault activity in a Late Quaternary closed-lake graben basin (Albacete, SE Spain). Geomorphology, 102(1), 169-178.
28 Advances in Active Tectonics and Speleotectonics 2015, Vienna, Austria
Mega earthquake affecting the Cacahuailpa cave, Mexico
Raúl Pérez-López1, Victor H. Garduño-Monroy2, Miguel. A. Rodríguez-Pascua1& Isabel Israde- Alcántara2 1 IGME – Instituto Geológico y Minero de España, Área de Investigación en Riesgos Geológicos. Madrid, España. Email: [email protected] , m.rodrí[email protected] 2 Universidad Michoacana San Nicolás de Hidalgo. Morelia. México. Email: [email protected]
The “Cacahuamilpa” cave is located in the central part of Mexico (Guerrero State of Mexico). This karst system is located within the “Ixtapan” Valley, a NW- SE elongated valley. The Nevado de Toluca volcano (4558 m.a.s.l.) is the highest peak in the surroundings and the karst is determined by two fluvial channels: the “San Jerónimo” (running N-S) and the “Chontalcoatlán” (E-W) rivers. The lowest topographic point corresponds with the cave entrance of Cacahuamilpa, 1000 m.a.s.l. The Amacuzac River rises from the cave pit. This cave is included into “La Estrella” Karst System, which is constituted by lots of caves: i.e. “Cuevas Pacheco”, “Cueva Agua Brava”, “Gruta de Acuitlapán” and “Cuevas de La Estrella”, among other minor caves. The geology of the cave mainly affects the so-called Morelos Unit, a stratified limestone and dolostone sequence (Lower Cretaceous, Fries, 1960), with a maximum thickness of 900 m. The Quaternary deposits are volcanic andesitic rocks and basalts and the youngest ones are Holocene travertine. Hydrothermal activity related with active volcanoes is described in “Ixtapan” and “Tonatico” areas (35º-40ºC water temperature)(Fries, 1960).The cave topography shows almost 1 km of a main hall oriented E-W with large dimensions. The highest cupule hall is 85m and the hall width 10-15m. Large stalactites and stalagmites decorate the cave. Different evidence of paleoseismic activity is observed along the cave: (a) fallen and oriented stalagmites, (b) fallen and oriented stalactites, (c) broken travertine, (d) abrupt displacement of stalagmites and (e) systematic fractures affecting the walls and columns. The most spectacular paleoseismic feature is the fallen large stalactite "Piedra Solar", with a dimension of 4m width and longitude larger than 16m. In this work, we have analysed a set of fallen and broken stalagmites. The dimension and orientation of the stalagmites suggest an earthquake pulse responsible of the ground shaking from NE-SW and with a magnitude greater than M7.5. Absolute dating by U-Th series of the newest stalagmites, which growth on the scar of the broken ones, indicate that this earthquake could occur in the year 400 CE (Pérez-López et al., 2011). This date is in agreement with the date of a large historical earthquake which affected Teotihuacan culture and is well- oriented with the seismic ray from the Mesoamerican Trench. (Pérez-López, 2012). This work has been partially supported by the Spanish Project SISMOSIMA, CGL2013-47412-C2-2-P.
References: Fries, C. (1960). Geología del Estado de Morelos ... Instituto Geológico de México, Boletín nº 60(9), 236p. Pérez-López et al., (2011).could large palaeoearthquakes break giant stalactites in Cacahuamilpa cave? (taxco, central méxico). 2nd INQUA-IGCP-567 International Workshop on Active Tectonics, Earthquake Geology, Archaeology and Engineering, Corinth, Greece. Pérez_López, (2012). Ancient earthquakes hit the Quetzalcóatl Pyramid at Teotihuacán (México). Was it a stricken critical facility? Quaternary International 11/2012; 279-280:375.
29 Advances in Active Tectonics and Speleotectonics 2015, Vienna, Austria
Speleoseismology of Benis cave: evidence of a M6 paleoearthquake 75 yr BP
Raúl Pérez-López1, Enrique Bañón2, Magda Patyniak1, 3, Juan J. Durán-Valsero1, Jorge L. Giner- Robles4, M.A. Rodríguez-Pascua1 & Jose J. Martínez-Díaz5
1 IGME – Instituto Geológico y Minero de España. C/Ríos Rosas 23, Madrid 28003. SPAIN, [email protected] 2 Espeleoclub RESALTES. Molina del Segura, SPAIN, [email protected] 3 University of Potsdam, Am Neuen Palais 10, House 9 14469 Potsdam, GERMANY, [email protected] 4 Universidad Autónoma de Madrid. Madrid, SPAIN, [email protected] 5 Universidad Complutense de Madrid. Madrid, SPAIN, [email protected]
Caves developed in areas featured by active tectonics are commonly developed in active faults. Hence, fault-caves show a wide range of different evidence of paleoseismic records inside the cave: speleo-seismites or seismothems. Benis Cave is located at the south east part of Spain, in Murcia province. This is the deepest cave into the area, 350 m depth, and it is developed in Upper Cretaceous dolostone and Tertiary limestone. The topography of Benis shows two well-differenced part of the cave: (1) vertical phreatic tubes (0-150 m depth) and (2) Fault-plane karst cave. The first part are vertical tubes of circular section (2-3m width) developed along N-S and E-W calcite vein. This zone is decorated by scallops. The union point with the fault plane in depth (zone 2) is a fault gauge area at -150m in depth. The fault plane is N-S trending and dipping 75ºE. Striation on the fault plane suggests normal faulting with left-lateral component, in agreement with the active stress field (SHmax NE-trending). Moreover, this fault has surface expression with 5 km of length and affecting Quaternary colluvium deposits.
Paleoseismic evidence inside Benis include roof ceiling collapses related to earthquake shaking, horizontal displacement of pop-corn travertines, movements of the fault planes fossilized by speleothems and coseismic blocks broken. In this work, we have measured different evidence of the last earthquake triggered by the fault-cave: the fault coseismic offset, the fault plane and the surface trace of the fault and an earthquake of M6.5 can be inferred. Furthermore, dating lynx skeletons found inside the cave and probably related the dead with the earthquake obtained an age of 75 kyrs BP by aminoacid razemization.
Figure 1. 3D schematic sketch of the topography of Benis Cave and relationship with the main geological units and the fault This work has been partially supported by plane. Beach balls are points with paleoseismic evidence, the Spanish Project SISMOSIMA, yellow triangle is the contact point with Quaternary infill of valleys, and red triangle indicates the depth of the location of CGL2013-47412-C2-2-P and INTERGEO skeletons of Linx. The blue triangle indicates the former CGL2013-47412-C2-1-P. phreatic level before the XXth century water pumping.
30 Advances in Active Tectonics and Speleotectonics 2015, Vienna, Austria
Quaternary fault activity revealed in caves in the Eastern Alps
Plan Lukas 1, Baroň Ivo 1, Grasemann Bernhard 2 & Mitrovic Ivanka 12 1 Natural History Museum Vienna, Geology Department, Museumsplatz 1/10, 1070 Wien, Austria, lukas.plan@nhm- wien.ac.at; [email protected] 2 University of Vienna, Dep. for Geodynamic and Sedimentology, Althanstr. 14, 1090 Wien, Austria, [email protected]; [email protected];
Several caves in the Eastern Alps were investigated for indicators of active tectonics or past earthquakes such as displaced gallery sections or deformed flowstone. Broken speleothems are very common in the Eastern Alps. Extra care is necessary when describing them as indicators for active tectonics in the Alpine environment as most caves suffered from frost scattering during Pleistocene glaciations. The best investigated cave so far is Hirschgrubenhöhle in Mt. Hochschwab in the eastern part of the Northern Calcareous Alps. Its development is controlled by preferred karstification along ENE- striking sinistral faults paralleling the SEMP (Salzachtal-Ennnstal-Mariazell-Puchberg) Fault System. Fault surfaces are often associated with cohesive and non-cohesive cataclasite suggesting progressive deformation during exhumation. A branch of the sinistral SEMP cut through the cave which caused shearing of stalagmites, faulted flowstone and flowstone showing fault striations. These striations, and offsets of cave walls, prove at least 20 cm of sinistral strike-slip movement. Fault striae and faulted flowstone are overgrown by younger undeformed layers of flowstone. The youngest age of the flowstone belonging to the pre-damage generation is ca. 118 ka BP (end of the Last Interglacial) and the oldest age of post-event layer is ca. 9 ka BP (early Holocene). These ages bracket the time of the sinistral faulting which coincides with a growth hiatus of the flowstone during the last glacial period, consistent with the high alpine setting of the cave. These observations, in combination with other data, suggest that the SEMP Fault System accommodates active lateral extrusion of the central Eastern Alps with kinematics similar to the Oligocene and Miocene ones (Plan et al. 2010). A nearby cave (Potentialschacht) also shows a parallel fault with similar features but dating was not successful yet as the analyzed flowstone samples were too old or contained too much detritus. For another cave in Hochschwab (Speikbodenhöhle) preliminary dating of a normal fault indicates an activity between 364 and 51 ka BP. Considering that these caves are at altitudes between 1900 and 2100 m, long hiatuses in flowstone growth due to Pleistocene glaciations are common, because the caves were frozen and no water was available. At the eastern termination of the SEMP fault near the Vienna Basin, in Emmerberghöhle a parallel sinistral fault with 4 cm of offset was investigated. Dating of broken versus unbroken flowstones revealed a fault activity between 77 and 136 ka BP. The best examples of faulted cave galleries and deformed flowstone were found in Wartburghöhle, a part of the Obir Caves in the southernmost part of Austria. The cave is located few kilometers north of the Periadriatic Fault that separates the Eastern Alps from the Southern Alps. Deformed flowstones along a fault with 40 cm offset were dated and show an activity between 7 and 45 ka. A major breakdown event within a massive flowstone wall could be dated between 9 and 19 ka. For some caves such as Bärenkogelhöhle I (Semmering area, Styria) the orientation of the fracture and or surface morphology observed from laser scan data indicated that the deformation in the cave is caused by gravitational mass movements. Therefore these caves were not further investigated. Most of the work was done within the framework of a Project of the Austrian Science Fund (FWF) Project No: P25884-N29
31 Advances in Active Tectonics and Speleotectonics 2015, Vienna, Austria
Installation of an automated fault displacement monitoring system at a geological test site in northern Bohemia
Matt D. Rowberry1, Xavi Marti2,3 & Josef Stemberk1 1 Institute of Rock Structure & Mechanics, Czech Academy of Sciences, v.v.i, V Holešovičkách 41, 182 09 Prague 8, Czech Republic, [email protected] & [email protected] 2 Institute of Physics, Czech Academy of Sciences, v.v.i., Cukrovarnická 10, 162 53 Prague 6, Czech Republic 3 IGS Research, Calle La Coma, Nave 8, 43140 La Pobla de Mafumet, Tarragona, Spain, [email protected]
Fault displacements have been monitored at a geological test site in Bedřichov Tunnel, near Liberec, in northern Bohemia for more than a decade. The data are generated by four mechanical extensometers: two installed across faults orientated broadly NW-SE and two across faults orientated broadly NE-SW. These instruments measure rotations in two perpendicular planes and displacements in three dimensions using the moiré phenomenon of optical interference. We recently established an automatic fault displacement monitoring system based on the existing, but hitherto manual, mechanical extensometers. This system adopts entirely new approaches to data acquisition, data processing, and data interpretation. Data acquisition benefits from the fact that the tunnel incorporates 230V electrical sockets and RJ-45 Ethernet sockets which enable automatic configuration using the Dynamic Host Configuration Protocol (DHCP). From a network perspective our monitoring system comprises: a relay board with TCP/IP access so as to be able to hard reset the electronic components online; programmable cameras with 64GB of data storage and TCP/IP access; and a programmable climatic station with 1 MB of data storage and TCP/IP access. The monitoring system records the moiré patterns generated by the mechanical extensometers every five minutes along with a range of climatic parameters at each of the monitoring points. These moiré patterns are processed immediately using a pioneering generic fitting procedure. The generic fitting procedure greatly improves the sensitivity of the mechanical extensometer and so it supersedes the conventional procedure in which each moiré interference fringe is counted individually. Interpretation of the obtained data, in accord with the concept of ‘big data’, is conducted in four discrete steps: first, each data stream is compiled into a single database with synchronised timestamps; second, the database is interrogated to define specific events of interest; third, the causal sequence for each defined event of interest is analysed; fourth, the most commonly reoccurring causal sequences are constrained. The latter is particularly important as it enables us, for the first time, to provide a comprehensive assessment of the factors responsible for initiating displacements at each monitoring point and to predict the future behaviour of each fault. This automatic fault displacement monitoring system has great potential for studies of active tectonics. It can, at present, be established anywhere with a guaranteed power supply and means of telecommunications. Ongoing research continues to investigate robust technological solutions so that, in the future, the monitoring system can be installed in far more remote locations such as caves or mountainous regions. Further reading Marti, X., Rowberry, M.D., Blahůt. J., 2013. A MATLAB® code for counting the moiré interference fringes recorded by the optical-mechanical crack gauge TM-71. Computers & Geosciences 52: 164-167. Rowberry, M.D., Kriegner, D., Holý, V., Frontera, C., Llull, M., Olejník, K., Martí, X., 2015. The instrumental resolution of a moiré extensometer in light of its recent automatisation. Measurement, under review. Stemberk, J., Košťák, B., 2008. Recent tectonic microdisplacements registered in Bedřichov Tunnel “A” in the Jizerské Hory Mts (N Bohemia). Acta Geodynamica et Geomaterialia 5: 377-388.
32 Advances in Active Tectonics and Speleotectonics 2015, Vienna, Austria
Morphostructure analysis of Waitzendorf and Diendorf fault - Some preliminary results
Jakub Stemberk1,2, Kurt Decker3, Petra Štěpančíková2
1 Department of Physical Geography and Geoecology, Charles University in Prague, Albertov 6, Prague 2, 128 43, Czech republic; [email protected] 2 Institute of Rock Structure and Mechanics, Academy of Sciences of the Czech Republic, Department of Neotectonics and Thermochronology, V Holešovičkách 41, Prague 8, 182 09, Czech Republic 3 Department for Geodynamics and Sedimentology, University of Vienna, Althanstrasse 14, A-1090 Vienna, Austria
Morphologically clearly visible Waitzendorf fault and Diendorf fault are situated in Lower Austria between Retz, Pulkau and Maissau on the SE edge of Bohemian Massif. According to older research provided in this area by many authors (Fikdor et al. 1977, Decker 1999, Sieberl et al. 1986- 1998, Rötzel 1996, Havlíček 2010, etc.), these faults could be active during Quarternary. Our research have started at the beginning of summer 2015 and is focused on analysis of all available cartographic materials (geological and topographic maps), available literature and mainly on own detail geomorphological mapping of selected landforms. Spatial distribution of these landforms such as gullies, erosion trenches, dellens, alluvial plains, alluvial fans, springs, swamps, river terraces, could potentially indicate recent tectonic activity on studied faults. Moreover, stream network parameters (based on DEM data) such as changes in erosion intensity indicated in longitudinal profiles, slope gradient and Stream Length (SL) index (Hack 1973) for river basin have been analyzed. The results will also complete the research focused on tectonics in the adjacent areas, e.g. monitoring using dilatometric gauges TM71 installed in the Ledové sluje - Ice caves (Czech Rep.), etc. Some of preliminary results will be presented.
Keywords: Diendorf fault, Waitzendorf fault, active tectonics, morphostructure analysis, SL index, Bohemian Massif, Lower Austia
References: Decker, K. (1999): Tektonische Auswertung integrierter geologischer, geophysikalischer, morphologischer und strukturgeologischer Daten. Projekt N-C-036/F/98 Geogenes Naturraumpotential Horn-Hollabrunn Figdor, H. & Scheidegger, A. E. (1977) Geophysikalische Untersuchungen an der Diendorfer Störung. Verh. Geol. B.-A., 1977/3, p. 243-270. Hack, J.T. (1973): Stream-profile analysis and stream-gradient index. U.S. Geological Survey Journal of Research 1, p. 421–429.
33 Advances in Active Tectonics and Speleotectonics 2015, Vienna, Austria
Slow aseismic fault slip recorded across Europe
Josef Stemberk1 & Matt D. Rowberry1
1 Institute of Rock Structure & Mechanics, Czech Academy of Sciences, v.v.i, V Holešovičkách 41, 182 09 Prague 8, Czech Republic, [email protected] & [email protected]
The EU-TecNet monitoring network was established more than ten years ago to record fault displacements across selected tectonic structures in the shallow crust. The network comprises more than one hundred fifty sites, most of which are situated underground, spread across the globe (www.tecnet.cz). Fault displacements are recorded in three dimensions using specially designed optical-mechanical crack gauges known as TM-71s. Data obtained during the past decade demonstrate that long periods of tectonic quiescence alternate with shorter periods of increased fault activity. It has been found that these periods of increased fault activity occur contemporaneously across distinct tectonic units. These periods are interpreted to reflect the widespread redistribution of stress and strain through the shallow crust. Since 1992, two displacement cycles, each lasting several years, have been identified along major European deep seated faults including the Sudetic Marginal Fault and the Upper Rhine Graben Margin Fault. It is possible to correlate the identified displacement cycles with the strongest global earthquakes which have occurred during the past decade. The global influence of the these events is seen from the association between anomalous fault displacements and sudden changes in radon and carbon dioxide concentrations recorded in the
Bohemian Massif and Western Carpathians before both the MW = 9.1 Indian Ocean Earthquake off the coast of Sumatra on 26.12.2004 and the MW = 9.0 Tōhoku Earthquake off the coast of Japan on 11.03.2011. Furthermore, during the last fifteen years, accelerated or anomalous fault displacements have been recorded at monitoring sites situated in, or close to, the epicentre areas of some of the strongest earthquakes in Europe. Examples include the M = 5.2 Waldkirch Earthquake in Germany on 05.12.2004; the M = 3.2 Vrbové Earthquake in Slovakia on 13.03.2006; the M = 6.3 L’Aquila Earthquake in Italy on 06.04.2009; the M = 3.7 Postojna Earthquake in Slovenia on 15.01.2010; the M = 5.9 Modena Earthquake in Italy on 20.05.2012; and the M = 4.5 Ilirska Bistrica Earthquake in Slovenia on 22.04.2014. These results indicate that the strongest regional and global earthquakes do not occur randomly but, instead, result from relatively rapid or sudden changes in regional and global stress fields. Further reading Briestenský, M., Stemberk, J., Petro, L., 2007. Displacements registered around the 13 March 2006 Vrbové Earthquake, M=3.2 (Western Carpathians). Geologica Carpathica 58, 487-493. Briestenský, M., Thinová, L., Praksová, R., Stemberk, J., Rowberry, M.D., Knejflová, Z., 2014. Radon, carbon dioxide, and fault displacements in central Europe related to the Tōhoku Earthquake. Radiation Protection Dosimetry 160, 78-82. Briestenský, M., Thinová, L., Stemberk, J., Rowberry, M.D., 2011. The use of caves as observatories for recent geodynamic activity and radon gas concentrations in the Western Carpathians and Bohemian Massif. Radiation Protection Dosimetry 145, 166-172. Košťák, B., Mrlina, J., Stemberk. J., Chán, B., 2011. Tectonic movements monitored in the Bohemian Massif. Journal of Geodynamics 52, 34-44. Stemberk, J., Košťák, B., Cacoń, S., 2010. A tectonic pressure pulse and increased geodynamic activity recorded from the long-term monitoring of faults in Europe. Tectonophysics 487, 1-12. Stemberk, J., Briestenský, M., Cacoń, S., 2015. The recognition of transient compressional fault slow-slip along the northern shore of Hornsund Fjord, SW Spitsbergen, Svalbard. Polish Polar Research 36, 109-123.
34 Advances in Active Tectonics and Speleotectonics 2015, Vienna, Austria
Quaternary tectonics on the Sudetic Marginal Fault as revealed by trenching and geophysics (Kamenička site)
Petra Štěpančíková1, Petr Tábořík1,2, Filip Hartvich1, Jakub Stemberk1,2, 3 4 5 Thomas Rockwell , Ona Corominas & Neta Wechsler
1 Inst. of Rock Structure and Mechanics, Czech Academy of Sciences, Prague, Czech Rep. 2 Faculty of Science, Charles University, Prague, Czech Rep. 3 Dpt. of Geological Sciences, San Diego State University, California 4 Faculty of Geology, University of Barcelona, Spain 5 Dpt. of Geophysics, Atmospheric and Planetary Sciences, Tel-Aviv University, Israel
Paleoseismic trenching, geophysical survey, and radiometric dating were used to study the late Quaternary history of the morphologically pronounced NW-SE trending Sudetic Marginal Fault (SMF), situated at the northeastern limit of the Bohemian Massif in central Europe. In the first part of the study eighteen trenches were opened and twenty-nine electric resistivity profiles (ERT) measured at the Bílá Voda site to study the 3D distribution of a beheaded alluvial fan on the NE block of the fault. A small stream with an asymmetric valley situated about 40-60 m to the SE of the fan apex was interpreted as the source channel. Optically stimulated luminescence yielded ages of ~25.8 ± 1.6 ka for the deposits within the fan apex and radiocarbon dating 40.9 ± 2.5 ka for fault- related colluvial wedge farther from the apex. Locally preserved unfaulted strata yielded radiocarbon ages 8.2 – 9.7 ± 0.02 ka. Assuming a ~25 ka OSL age for the base of the fan apex yields a left-lateral slip rate of 2.8 to 3.5 mm/yr during Late Pleistocene and no displacement during Holocene. The study site Kamenička is situated 2 km to the south-east from Bílá Voda site, on a floodplain of the Od Tří Lip Brook with approximately 45 m left-laterally offset valley side by the SMF. While the general strike of the mountain front within the Bílá Voda area is 125° and the fault in the trenches showed strike 132° dipping to the NE (ca 75°), the mountain front segment further to the SE at the Kamenička site bends slightly to 145°. No morphological indication of the fault was observed in the floodplain, even though a detailed digital elevation model based on airborne LiDAR data was used. Thus, we conducted 25 ERT profiles including pseudo3D profiling, and areal resistivity mapping using dipole electromagnetic profiling (DEMP) in order to localize the trace of the SMF as well as to reveal the thickness of the valley infill for optimizing the position of the trenches. Three trenches (with lengths of 20, 30, and 70 m) and five test pits were excavated in order to reveal the Late Quaternary faulting. The very late Pleistocene to Holocene infill of the valley, up to 3-4m thick, was not faulted, while underlying gravels were exposed juxtaposed to crystalline bedrock at the fault zone. The fault dipping to the SW showed reverse component with gravels thrusted over the bedrock, which is in agreement with left-lateral slip within the zone where fault strike changes. The occurrence of non-faulted Holocene sediments is also in agreement with the results from Bílá Voda site.
35 Advances in Active Tectonics and Speleotectonics 2015, Vienna, Austria
Earthquake research from space by using InSAR
Henriette Sudhaus1
1 Deutsches GeoForschungsZentrum GFZ, Helmholtzstraße 6/7, 14467 Postdam, Germany, [email protected]
What makes InSAR (Interferometric Synthetic Aperture Radar) so interesting for earth sciences and what are the future prospects for earthquake research are the topics of this presentation. In a nutshell, with InSAR we can sense earth surface movements with high precision from space by using radar waves with a technology called interferometric synthetic aperture radar - InSAR. Earth surface movements are caused by tectonic plate motion and faulting, by volcanic activities that in- or deflate volcanic bodies, by large-scale fluid withdrawal that leads to compaction of rock (oil and gas production, water pumping), and others. By comparing two SAR images any distance changes between intact ground and sensor that have developed in between can be calculated. In numbers the precision of these InSAR motion measurements reaches centimetre level and can be increased in time series analyses to millimetre. The spatial resolution ranges - depending on surface conditions and sensor – from some tens of meter down to one meter. The temporal resolution depends on the time intervals at which the images are taken and with that on the revisit intervals of the sensor. These intervals decreased from about a month for older missions to between 11 and 14 days nowadays or even higher rates for missions with more than one just one sensor. The costs for the scientific use of these data is down to zero for several archived data sets and completely free of charge for the Sentinel 1 satellite data, a sensor of the European space agency ESA orbiting since last year. Large crustal earthquakes deform rocks and displace the Earth's surface. Depending on the magnitude these surface displacement can reach several meters close to the rupture and effect areas that reach out for tens to hundreds of kilometres. The characteristics of the surface motion can tell us about many characteristics of the earthquake source itself and helps to understand the development and nature of faulting. In the presentation I will discuss how InSAR can complement the classical seismological earthquake research and the benefit a better combination of the two disciplines could bring.
36 Advances in Active Tectonics and Speleotectonics 2015, Vienna, Austria
Quaternary faulting in the Tatra Mts. from the perspective of the cave morphology and fault-slip analysis
Jacek Szczygieł1 1 Department of Fundamental Geology, Faculty of Earth Sciences, University of Silesia, Będzińska 60, 41-200 Sosnowiec, Poland; [email protected]
The Tatra Mountain block is a fold-and-thrust structure which has been uplifting since the Miocene (Burchart, 1972). The rate of uplift in the Tatras is highest to the south causing tilting and rotation towards the north (Bac-Moszaszwili, 1995). Faults shifted youngest passages of the caves are evidence for the Quaternary activity of the Tatras area. Such faults were already investigated by Wójcik & Zwoliński (1959), however, their interpretation in relation to the current state of knowledge needs revision. In 8 caves on 16 sites, faults younger then passages have been recorded. Based on geomorphological observations and stress tensor reconstruction two different mechanisms are proposed as responsible for the development of these displacements. The first mechanism concerns faults that are located above the valley bottom and at a short distance from the surface, with fault planes oriented sub-parallel to the slopes. The radial extension and vertical σ1 indicate that these faults are the result of gravity sliding. Trigger mechanism was probably the relaxation after valleys incision, and not tectonic activity sensu stricto. The faults caused by the second mechanism operated under WNW – ESE oriented extension with σ1 plunging steeply toward the west. This tectonic stress field is generated as a result of tilting of the Tatra Mts. and is expressed by normal dip-slip or oblique-slip displacements. The faults of this group are located under the valley bottom and / or opposite or oblique to the slopes. The process involved the pre-existing weakest planes in the rock complex. For example in the Śnieżna Śtudnia Cave, even 400 m under the valley bottom, displacement took place along bedding plane dipping steeply to the south. Tilting toward N caused the hanging walls to move under the massif and not toward the valley. It proving that the cause of these movements was tectonic activity and not gravity (Szczygieł, 2015). Both types of faults have relatively small displacements up to ~30cm. The morphology of passages was slightly affected. Near the faults do not occur breakdowns or highly fractured zones. It could be conclude that faults with displacements of several meters interpreted by Wójcik & Zwoliński (1959) as being younger than the caves should now be classified as older structures, the surfaces of which have been commandeered and exposed by speleogenesis. The presence of neotectonic faults with greater displacements has not been excluded, but they would have had a much greater impact on morphology than the observed features (Szczygieł et al., 2015).
References: Bac-Moszaszwili M., 1995 – Diversity of Neogene and Quaternary tectonic movements in Tatra Mountains. Folia Quaternaria, 66: 131—144. Burchart J., 1972 – Fission-track age determinations of accessory apatite from Tatra Mts., Poland. Earth Planetary Science Letter, 15: 418—422. Szczygieł J., 2015 – Quaternary faulting in the Tatra Mts., evidence from cave morphology and fault-slip analysis, Geologica Carpathica, 66, In Press Szczygieł J., Gaidzik K., Kicińska D., 2015 – Tectonic control of cave development: a case study of the Bystra Valley in The Tatra Mts., Poland. Annales Societatis Geologorum Poloniae, 85, In Press Wójcik Z. & Zwoliński S., 1959 – Młode przesunięcia tektoniczne w jaskiniach tatrzańskich. Acta Geologica Polonica, 9: 319—338.
37 Advances in Active Tectonics and Speleotectonics 2015, Vienna, Austria
Small-scale seismites in cave clastic deposits: preliminary results from the Kalacka Cave, Tatra Mts., Poland
Jacek Szczygieł1, Wojciech Wróblewski2 & Maciej Mendecki3
1 Department of Fundamental Geology, Faculty of Earth Sciences, University of Silesia, Będzińska 60, 41-200 Sosnowiec, Poland; [email protected] 2 Institute of Geological Sciences, Jagiellonian University, Oleandry 2a, 30-063 Kraków, Poland; [email protected] 3 Department of Applied Geology, Faculty of Earth Sciences, University of Silesia, Będzińska 60, 41-200 Sosnowiec, Poland; [email protected]
The Kalacka Cave is 345 m long with 19 m of altitude difference and is located in the Bystra Valley in north-central part of the Tatra Mts. (Central Western Carpathians). The cave is developed in the thin-bedded limestone of the Middle Triassic and the massive limestone of Upper Jurassic of the Giewont Nappe. Previous research indicate Riss origin of the cave and Riss/Würm (Eemian in polish stratigraphy) filling by deposits from melting glaciers and backflooding as indicated two directions of palaeoflow. Faulting operated after cave passage enlargements have been recorded in the cave. In sump is 1,5 m high and 16 m long trench dug by explorers. It is partly filled by non- cemented siliciclastic deposits, predominantly fine-grained planar-laminated sandstones and siltstones. Soft sediments deformation are represented by water escape structures (various shapes conduits and wedges), ductile structures (disharmonic folds, fault-bend folds, upright antyclines) and brittle structures (autoclastic breccias, fault grading) are recognizable. The sump is located ~10 m to the west in a straight line from the displacements active after cave development. Fault-slip analysis of Quaternary faults from Kalacka Cave indicates gravity sliding due to relaxation as the cause of their activities. Despite that the displacement vector is only 10 cm long, shock triggered by such movement could initiate liquefaction of soft sediment. The liquefaction phenomenon (vulnerability index) is determined by a resonance frequency and a squared amplification coefficient. Using simple relations, well known in seismology, it can be demonstrated that the resonance frequency depends on the geometry of a ductile layer, thus the liquefaction is related to size of structure and a ground-motion frequency. It was therefore assumed that the small thickness sediment may be subjected to liquefaction by appearance of a high-frequency seismic event in the nearby surroundings. Additionally, the spatial orientation of structures makes it possible that the rockslide-triggered tremor, from the neighboring fault, could have affected the sediment. In the curvature of sump conduit change the direction from NW–SE to SW–NE, and around the curve, structures are poorly developed. To sum up, the thesis, that will be checked, is the seismites from Kalacka Cave, are not only a site with a rare structure but also the first site with seismites-like structures triggered by gravity sliding caused by relaxation.
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