Two‐layer scree/snow‐avalanche triggered by rockfall (Eastern Alps): Significance for sedimentology of scree slopes

Sedimentology - Tập 61 Số 4 - Trang 996-1030 - 2014
Diethard Sanders1, Lukas Widera1, Marc Ostermann1
1Institute of Geology and Palaeontology University of Innsbruck Innrain 52 A‐6020 Innsbruck Austria

Tóm tắt

AbstractRockfalls that trigger scree‐laden snow avalanches are common in mountain ranges, but the resulting avalanche development and its role in understanding the sedimentology of scree slopes are rarely described in detail. On Riepenwand (2774 m above sea‐level, Kalkkögel range, Alps), on 6 May 2011 a 5800 m3 rockfall of dolostone detached from the flank of a gorge in the upper part of the mountain. After first collapsing into the gorge, the fragmented rock mass fell down freely for 150 m onto a talus covered by coarse‐granular snow. Rockfall impact triggered a medium‐scale avalanche that developed: (i) a lower layer A of entrained, pure snow; and (ii) an upper layer B of clay‐sized to boulder‐sized fragments mixed with snow. This ‘two‐layer scree/snow avalanche’ halted in the distal slope segment of the talus. Boulders within layer B mainly came to rest in the distal part of the avalanche deposit. Fragments smaller than cobble‐size grade did not show obvious downslope segregation. With snowmelt, the rockfall fragments dispersed in layer B were concentrated to a clast‐supported veneer that was draped over the older talus surface upon slower melting of avalanche layer A. In the grain‐size fraction ≤16 mm, a mean of 5 wt% matrix (silt‐sized to clay‐sized grains) of the rockfall‐derived scree of layer B is similar to a mean matrix content of 7 wt% within stratified talus slopes of the Kalkkögel range. This similarity suggests that a major share of matrix – widespread in stratified talus – stems from rockfalls. The characteristics of the scree veneer as melt‐lag of a scree‐laden snow avalanche will be blurred with time. Fossil talus successions may contain a substantial proportion of scree carried down by snow avalanches. The formation of a distinct sedimentary facies of snow avalanche‐deposited scree is impeded by processes of redeposition and deposit modification on talus.

Từ khóa


Tài liệu tham khảo

Ampferer O., 1907, Über Gehängebreccien der nördlichen Kalkalpen, Jahrbuch der geologischen Reichsanstalt, 57, 727

Ampferer O., 1943, Die Schlußvereisung der Kalkkögel bei Innsbruck, Sitzungsberichte der Akademie der Wissenschaften in Wien, 152, 255

10.1007/BF00874329

10.1002/ppp.3430010203

10.2307/1551249

10.2307/1551594

10.1016/S0341-8162(98)00096-4

10.1046/j.1365-3091.1998.00200.x

10.1191/095968398674390284

10.1016/j.geomorph.2009.03.017

Brandner R. Resch W.andReiter F. (2003)Das Brennermesozoikum. Sedimentäre Faziesentwicklungen in metamorphen Gesteinen und tektonische Konsequenzen. Arbeitstagung der Geologischen Bundesanstalt Blatt 148 Brenner. Geological Survey of Austria Vienna 95–98.

Braunhofer D. (2011)Erscheinungen von Schneelawinen‐Erosion auf der Innsbrucker Nordkette. Unpubl. B.Sc. thesis University of Innsbruck 29pp.

Brückl E., 1974, Morphometrie einer Schutthalde, Mitteilungen der österreichischen geographischen Gesellschaft in Wien, 116, 79

10.3189/S0022143000011242

Brun E., 1987, Avalanche Formation, Movement and Effects, 183

10.3189/002214311798043870

10.1016/S0341-8162(99)00085-5

10.1016/j.coldregions.2010.04.005

10.1029/2003JB002465

10.5194/nhess-9-2107-2009

10.2307/520447

10.1016/0012-8252(95)00065-8

10.1007/BFb0117848

10.1029/2005JF000455

10.1002/(SICI)1096-9837(199912)24:13<1229::AID-ESP42>3.0.CO;2-1

10.1016/S0169-555X(03)00226-5

10.1038/20392

10.1002/ppp.378

10.1002/esp.1861

10.1016/j.geomorph.2004.11.021

10.1016/j.coldregions.2005.05.002

10.1016/j.geomorph.2005.09.007

10.1111/j.1468-0459.2010.00388.x

10.1016/0165-232X(82)90018-0

10.1007/BF01081371

Donofrio D.A., 2008, Kurzmitteilung zu Conodonten, Echinodermen‐ und Fischresten aus dem Brenner‐Mesozoikum (Kalkkögelgruppe SW Innsbruck, Tirol) und deren Paläotemperaturen, Geo.Alp, 5, 83

10.1191/0309133303pp359ra

10.1016/S0169-555X(02)00142-3

10.1139/t93-054

10.1007/978-1-4020-4037-5_1

Fitzharris B.B., 1984, Avalanche tarns, J. Glaciol., 30, 308, 10.3189/S0022143000006146

Folk R.L., 1974, The natural history of crystalline calcium carbonate: effect of magnesium content and salinity, J. Sed. Petrol., 44, 40

Frank W., 1987, Geodynamics of the Eastern Alps, 179

10.1002/9781118684931

10.1046/j.1365-3121.1997.d01-33.x

10.1029/2000TC900014

Fuhrmann S. (2012)Der Felssturz vom 6. 5. 2011 an der Riepenwand: Volumen und Charakteristika. Unpubl. B.Sc. thesis University of Innsbruck 37pp.

10.2307/1550348

Geyssant J., 1973, Stratigraphische und tektonische Studien in der Kalkkögelgruppe bei Innsbruck in Tirol, Verhandlungen der Geologischen Bundesanstalt, 3, 377

10.2307/1550656

Graf K., 2008, Der Felssturz am “Hellhore” in Kandersteg vom 16. August 2008, Bulletin für Angewandte Geologie, 13, 97

10.1029/2006JF000547

10.1002/ppp.501

10.5194/nhess-3-491-2003

10.1016/S0169-555X(99)00072-0

10.1002/esp.494

10.1002/esp.2250

10.1002/(SICI)1096-9837(199806)23:6<545::AID-ESP876>3.0.CO;2-E

10.1007/s00254-004-1043-y

10.1007/s00248-006-9051-y

10.1007/s10035-009-0163-1

10.3189/172756408787814915

10.1029/97RG00426

10.1130/0091-7613(2001)029<0115:NVOGMF>2.0.CO;2

10.1002/jqs.955

10.1016/j.quascirev.2009.03.009

10.1111/j.1541-0064.2009.00275.x

10.1111/1468-0459.00141

10.1016/S0169-555X(00)00035-0

10.1038/272710a0

10.1016/j.coldregions.2004.03.006

10.3189/002214309788608714

Kerschner H, 1986, Zum Sendersstadium im Spätglazial der nördlichen Stubaier Alpen, Tirol, Zeitschrift für Geomorphologie, Neue Folge, 65

10.2307/1552262

Kilian S. (2008)Untersuchung der feinkörnigen Matrix in aktiven felssturzdominierten Talus‐Hängen. Unpubl. B.Sc. thesis University of Innsbruck 42pp.

10.1177/0959683609353432

Krähenbühl R., 2004, Temperatur und Kluftwasser als Ursachen von Felssturz, Bulletin für angewandte Geologie, 9, 19

Krähenbühl R., 2006, Der Felssturz, der sich auf die Stunde genau ankündigte, Bulletin für angewandte Geologie, 11, 49

Ladurner J., 1932, Die Quartärablagerungen des Sellrain (Stubaier Alpen), Jahrbuch der geologischen Bundesanstalt, 82, 397

10.1002/ppp.624

10.1306/041301720166

10.3189/S0022143000010704

Lorenzi S. (2012)Grundlawinen im Spätwinter 2012 Nordkette bei Innsbruck. Merkmale und Erosionserscheinungen. Unpubl. B.Sc. thesis University of Innsbruck 32 pp.

Luckman B.H., 1977, The geomorphic activity of snow avalanches, Geogr. Ann., 59, 31, 10.1080/04353676.1977.11879945

10.2307/1550759

Luckman B.H., 1988, Debris accumulation patterns on talus slopes in Surprise Valley, Alberta, Géog. Phys. Quatern., 42, 247

10.2307/521289

10.1130/0016-7606(1999)111<1424:DFDEOP>2.3.CO;2

10.1002/ppp.393

10.1002/ppp.620

10.1016/S0169-555X(98)00116-0

10.2307/1551773

10.1016/j.geomorph.2011.04.010

McSaveney M. J.andDavies T. R. H. (2002)Rapid rock‐mass flow with dynamic fragmentation: inferences from the morphology and internal structure of rockslides and rock avalanches. In:Landslides from Massive Rock Slope Failure(EdsS. G.Evans G.Scarascia Mugnozza A.StromandR. L.Hermanns) pp.285–304.NATO Science Series Springer Dordrecht.

Meißl G., 1998, Modellierung der Reichweite von Felsstürzen. Fallbeispiele zur GIS‐gestützten Gefahrenbeurteilung aus dem Bayerischen und Tiroler Alpenraum, Innsbrucker Geographische Studien, 28, 1

10.1029/1999JB900189

10.1002/esp.3290180405

10.1046/j.1365-3091.1999.00210.x

10.1130/0016-7606(1991)103<1365:GCOTSA>2.3.CO;2

Nötzli J., 2005, Alpiner Permafrost – ein Überblick, Jahrbuch des Vereins zum Schutz der Bergwelt, 70, 111

10.1111/j.0435-3676.2006.00302.x

10.1016/j.quascirev.2005.07.004

10.1144/GSL.SP.2002.205.01.14

Pudasaini S.P., 2007, Avalanche Dynamics. Dynamics of Rapid Flows of Dense Granular Avalanches, 602

10.1016/S0378-4371(02)01143-3

Rapp A., 1959, Avalanche boulder tongues in Lappland, Geogr. Ann., 41, 34

10.2307/520126

10.1007/s10346-010-0206-z

Reichhalter F. (2009)Untersuchung der feinkörnigen Matrix in aktiven felssturzdominierten Talus‐Hängen. Unpubl. B.Sc. thesis University of Innsbruck 35pp.

Reiter F., 2005, Indications for activity of the Brenner normal fault zone (Tyrol, Austria) from seismological and GPS data, Austrian J. Earth Sci., 97, 16

10.1111/j.1365-3091.1976.tb00047.x

10.5194/nhess-2-211-2002

10.1016/S0964-8305(97)00048-6

Sanders D, 2011, Hitherto undescribed pattern of rock cliff/talus development: The ‘breach concept’, Geophys. Res. Abstracts, 13, EGU2011‐1611

10.1007/s10347-008-0175-z

10.1007/s10347-009-0194-4

10.1017/S0022112079000525

10.1007/BF01301796

10.1007/s00015-004-1113-x

10.2307/1552151

10.2307/1551774

10.5194/nhess-2-169-2002

10.3189/172756401781819058

10.1029/2005JF000391

10.1029/2006JF000688

10.3189/002214310793146287

10.1306/031104740736

10.1002/esp.1982

Stock G. M. Luco N. Collins B. Harp E. Reichenbach P.andFrankel K. L. (2012)Quantitative rock‐fall hazard and risk assessment for Yosemite Valley Yosemite National Park California. Report Yosemite National Park Service and US Geological Survey Washington DC 92pp.

10.1016/j.coldregions.2008.01.005

10.1016/S0165-232X(03)00060-0

Van Husen D, 1987, Die Ostalpen in den Eiszeiten, 24

Voellmy A., 1955, Über die Zerstörungskraft von Lawinen, Schweizerische Bauzeitung, 73, 159

10.1002/grl.50134

10.2307/521102

10.1111/j.1472-4669.2010.00256.x

10.2307/1550981

10.1130/0016-7606(2000)112<75:UJRFAH>2.0.CO;2

10.5194/nhess-8-421-2008

10.1002/esp.3206

Thông tin
Thông tin xuất bản

Sedimentology

Tập 61 Số 4

996-1030

Thông tin tác giả