Giant landslide deposits in northwest Argentina
Abstract
Giant Quaternary landslide deposits occur along mountain fronts in the structural transition zone between the high-angle reverse-fault-bounded Sierras Pampeanas and the low-angle thrust belt of the Sierras Subandinas. There are two modes of occurrence: (1) chaotic masses without distinct geometry, and (2) masses with distinct lobate geometry similar to glacial moraines. Type (1) deposits occur where the moving rock mass followed a narrow valley and blocked the drainage. Many of these caused subsequent formation of lakes and changed the sedimentation processes on pediments at the mountain fronts. In type (2) deposits, lateral and frontal ridges are up to 10 m higher than the interior parts; in some places pressure ridges within the lobes are well preserved. Type (2) deposits show reverse grading and were deposited on relatively smooth pediments or alluvial fans. The lobate geometry strongly suggests that type (2) deposits are a product of flowage and are debris stream or sturzstrom deposits (sense of Heim, 1932 and Hsu, 1975). All investigated deposits occur in areas of demonstrated Quaternary faulting and are interpreted as the result of tectonic movements, although structural inhomogeneities in the source area may have been a significant factor for some of the landslides. No datable materialsmore »
- Authors:
- Publication Date:
- Research Org.:
- Servicio Geologico de Argentina, Buenos Aires
- OSTI Identifier:
- 6652963
- Report Number(s):
- CONF-8510489-
Journal ID: CODEN: GAAPB
- Resource Type:
- Conference
- Journal Name:
- Geol. Soc. Am., Abstr. Programs; (United States)
- Additional Journal Information:
- Journal Volume: 17; Conference: 98. annual meeting of the Geological Society of America, Orlando, FL, USA, 28 Oct 1985
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 58 GEOSCIENCES; ARGENTINA; LANDSLIDES; GEOLOGY; TECTONICS; ALLUVIAL DEPOSITS; GEOLOGIC FAULTS; GEOMETRY; ORIGIN; QUATERNARY PERIOD; SEDIMENTS; STRATIGRAPHY; CENOZOIC ERA; DEVELOPING COUNTRIES; GEOLOGIC AGES; GEOLOGIC DEPOSITS; GEOLOGIC FRACTURES; GEOLOGIC STRUCTURES; LATIN AMERICA; MATHEMATICS; SOUTH AMERICA; 580100* - Geology & Hydrology- (-1989); 580201 - Geophysics- Seismology & Tectonics- (1980-1989)
Citation Formats
Fauque, L, Strecker, M R, and Bloom, A L. Giant landslide deposits in northwest Argentina. United States: N. p., 1985.
Web.
Fauque, L, Strecker, M R, & Bloom, A L. Giant landslide deposits in northwest Argentina. United States.
Fauque, L, Strecker, M R, and Bloom, A L. 1985.
"Giant landslide deposits in northwest Argentina". United States.
@article{osti_6652963,
title = {Giant landslide deposits in northwest Argentina},
author = {Fauque, L and Strecker, M R and Bloom, A L},
abstractNote = {Giant Quaternary landslide deposits occur along mountain fronts in the structural transition zone between the high-angle reverse-fault-bounded Sierras Pampeanas and the low-angle thrust belt of the Sierras Subandinas. There are two modes of occurrence: (1) chaotic masses without distinct geometry, and (2) masses with distinct lobate geometry similar to glacial moraines. Type (1) deposits occur where the moving rock mass followed a narrow valley and blocked the drainage. Many of these caused subsequent formation of lakes and changed the sedimentation processes on pediments at the mountain fronts. In type (2) deposits, lateral and frontal ridges are up to 10 m higher than the interior parts; in some places pressure ridges within the lobes are well preserved. Type (2) deposits show reverse grading and were deposited on relatively smooth pediments or alluvial fans. The lobate geometry strongly suggests that type (2) deposits are a product of flowage and are debris stream or sturzstrom deposits (sense of Heim, 1932 and Hsu, 1975). All investigated deposits occur in areas of demonstrated Quaternary faulting and are interpreted as the result of tectonic movements, although structural inhomogeneities in the source area may have been a significant factor for some of the landslides. No datable materials have yet been found associated with the deposits.},
doi = {},
url = {https://www.osti.gov/biblio/6652963},
journal = {Geol. Soc. Am., Abstr. Programs; (United States)},
number = ,
volume = 17,
place = {United States},
year = {Tue Jan 01 00:00:00 EST 1985},
month = {Tue Jan 01 00:00:00 EST 1985}
}