Experimental soft‐sediment deformation: structures formed by the liquefaction of unconsolidated sands and some ancient examples

Sedimentology - Tập 43 Số 2 - Trang 279-293 - 1996
Geraint Owen1
1Department of Geography, University of Wales Swansea, Singleton Park, Swansea, SA2 8PP,UK

Tóm tắt

ABSTRACTThe effects of liquefaction in saturated sand bodies under a variety of driving forces are described from shaking table experiments, and structures from the geological record are presented which are analogous to the experimental structures. The collapse of sloping heaps of cross‐bedded sand under a gravitational body force generates low‐angle, essentially uncontorted stratification. A basal zone of shearing may be present, with steepened and folded foresets. Stretching of foresets may be accommodated on normal faults, and bottomsets may be contorted into inclined folds. In natural systems the substrate may also liquefy, causing deformation driven by an unevenly distributed confining load. Stratification in the surface bedform is flattened, and stratification in the substratum contorted. Experiments failed to produce relative displacement at the interface between stacked sand bodies. Liquefaction of gravitationally unstable systems in sands generates load structures comparable to those from sand‐mud systems. Recumbent‐folded deformed cross‐bedding is formed by current shear over a liquefied bed, as has been inferred from field and theoretical analyses. Shear of nonliquefied sand forms angular folds. Other deformation mechanisms, such as fluidization or seepage, may generate structures similar to all of these. Local water‐escape structures driven by fluidization occur in the upper parts of some liquefied sand bodies. They include cusps, sand volcanoes and clastic dykes. Transient cavities formed in some experiments and seemed to be preserved as breached cusps. Although the experiments tried to isolate individual driving forces, driving forces may operate together, and there may be a continuum between deformation driven by water escape and deformation driven by loading. Different structures from those described here may form where liquefaction develops in a buried layer as opposed to at the sediment surface.

Từ khóa


Tài liệu tham khảo

Allen J.R.L., 1970, The angle of initial yield of haphazard assemblages of equal spheres in bulk, Geol. Mijnb., 49, 13

10.1111/j.1365-3091.1972.tb00005.x

10.1144/gsjgs.134.1.0019

Allen J.R.L., 1982, Sedimentary Structures: their Character and Physical Basis

Allen J.R.L., 1982, Late Pleistocene (Devensian) glacio fluvial outwash at Banc‐y‐Warren, near Cardigan (west Wales), Geol. J., 17, 21

Allen J.R.L., 1985, Principles of Physical Sedimentology

10.1016/0037-0738(86)90006-0

10.1111/j.1365-3091.1972.tb00024.x

Ambraseys N., 1969, Liquefaction of soils induced by earthquakes. Bull. seismol, Soc. Am., 59, 651

Amick D., 1990, Characteristics of seismically induced liquefaction sites and features located in the vicinity of the 1886 Charleston, South Carolina earthquake, Seismol. Res. Lett., 61, 117, 10.1785/gssrl.61.2.117

Anketell J.M., 1970, On the deformational structures in systems with reversed density gradients, Ann. Soc. geol. Pol., 40, 3

10.1061/(ASCE)0733-9410(1993)119:3(543)

Bartsch‐Winkler S., 1984, Bedding types in Holocene tidal channel sequences, Knik Arm, Upper Cook Inlet, Alaska, J. sedim. Petrol., 54, 1239

10.1111/j.1365-3091.1970.tb00189.x

10.1139/e92-136

10.1111/j.1365-3091.1979.tb00976.x

10.1111/j.1365-3091.1979.tb00355.x

Dzulynski S., 1966, Sedimentary structures resulting from convection‐like pattern of motion, Ann. Soc. geol. Pol., 36, 3

Dzulynski S., 1962, On load‐casted ripples, Ann. Soc. geol. Pol., 32, 147

Dzulynski S., 1965, On ripple-load convolution. Bull. Acad. pol. Sci., Ser. Sci. geol. geogr., 13, 135

Finn W.D.L., 1970, Proc. 3rd Eur. Symp. Earthquake Eng., 253

10.1144/GSL.JGS.1957.113.01-04.19

10.1130/0016-7606(1966)77[1315:MEOTER]2.0.CO;2

Gray W.A., 1968, The Packing of Solid Particles

Greensmith J.T., 1965, Calciferous Sandstone Series sedimentation at the eastern end of the Midland Valley of Scotland, J. sedim. Petrol., 35, 223

10.1130/0091-7613(1992)020<0008:BSSDRN>2.3.CO;2

10.1002/gj.3350100203

Hendry H.E., 1975, Penecontemporaneous recumbent folds in trough cross‐bedding of Pleistocene sands in Saskatchewan, Canada, J. sedim. Petrol., 45, 932

10.1111/j.1365-3091.1982.tb01717.x

Housner G.W., 1958, The mechanism of sandblows, Bull. seismol. Soc. Am., 48, 155, 10.1785/BSSA0480020155

10.1680/geot.1993.43.3.351

10.1061/(ASCE)0733-9410(1983)109:2(172)

Jones B.G., 1972, Deformation structures in siltstone resulting from the migration of an Upper Devonian aeolian dune, J. sedim. Petrol., 42, 935

Jones G.P., 1962, Deformed cross‐stratification in Cretaceous Bima Sandstone, Nigeria, J. sedim. Petrol., 32, 231

Kolbuszewski J., 1950, Notes on the deposition of sands, Research, 3, 478

10.1007/BF01802902

10.1144/GSL.SP.1987.029.01.12

10.1306/212F7F1D-2B24-11D7-8648000102C1865D

10.1111/j.1365-3091.1975.tb00290.x

10.1111/j.1365-3091.1976.tb00051.x

Lowe D.R., 1974, The characteristics and origins of dish and pillar structures, J. sedim. Petrol., 44, 484

10.1002/gj.3350220509

10.1144/GSL.SP.1987.029.01.08

10.1007/978-94-011-0731-0

10.1130/0016-7606(1971)82[359:DOLLIE]2.0.CO;2

McKee E.D., 1962, Laboratory studies on deformation in unconsolidated sediment, Prof. Pap. US geol. Surv., 450, D151

McKee E.D., 1962, Experiments on intraformational recumbent folds in crossbedded sand, Prof. Pap. US geol. Surv., 450, D155

10.1144/GSL.SP.1995.094.01.06

10.1111/j.1365-3091.1994.tb01403.x

10.3208/sandf1972.14.4_25

Owen G.(1985)Mechanisms and controls of deformation in unconsolidated sands: an experimental approach.PhD thesis University of Reading.

10.1144/GSL.SP.1987.029.01.02

10.1306/D42679B5-2B26-11D7-8648000102C1865D

Owen G., 1995, Soft‐sediment deformation in upper Proterozoic Torridonian sandstones (Applecross Formation) at Torridon, northwest Scotland, J. sedim. Res., 65, 495

Pickering K.T., 1985, Flat stratification: two ancient examples ‐ discussion, J. sedim. Petrol., 55, 627

10.1007/978-3-642-61887-1

Ramberg H., 1981, Gravity, Deformation and the Earth's Crust

Rettger R.E., 1935, Experiments on soft‐rock deformation, Bull. Am. Ass. petrol. Geol., 19, 271

Rust B.R., 1968, Deformed cross‐bedding in Tertiary‐Cretaceous sandstone, Arctic Canada, J. sedim. Petrol., 38, 87

Seed H.B., 1979, Soil liquefaction and cyclic mobility evaluation for level ground during earthquakes, Proc. Am. Soc. Civ. Eng., J. Soil Mech. Found. Div., 105, 201

Seed H.B., 1971, Simplified procedure for evaluating soil liquefaction potential, Proc. Am. Soc. Civ. Eng., J. Soil Mech. Found. Div., 97, 1249, 10.1061/JSFEAQ.0001662

10.1144/sjg05040328

Selley R.C., 1962, The experimental production of sedimentary structures in quicksands, Proc. geol. Soc. London, 1599, 101

10.1017/S0016756800055175

10.1016/0031-0182(71)90036-8

Stewart H.B., 1956, Contorted sediments in modern coastal lagoon explained by laboratory experiments, Bull. Am. Ass. petrol. Geol., 40, 153

10.1016/0031-0182(73)90014-X

10.5575/geosoc.93.791

10.1016/0037-0738(93)90076-H

Youd T.L., 1977, Packing changes and liquefaction susceptibility, Proc. Am. Soc. Civ. Eng., J. Geotech. Eng. Div., 103, 918