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Are the Benches at Mormon Point, Death Valley, California, USA, Scarps or Strandlines?

Published online by Cambridge University Press:  20 January 2017

Jeffrey R. Knott*
Affiliation:
Department of Geological Sciences, California State University, Fullerton, P.O. Box 6850, Fullerton, California, 92834-6850
John C. Tinsley III
Affiliation:
United States Geological Survey, 345 Middlefield Road MS-975, Menlo Park, California, 94025
Stephen G. Wells
Affiliation:
Desert Research Institute, 2215 Raggio Parkway, Reno, Nevada, 89512
*
1To whom correspondence should be addressed. E-mail: [email protected].

Abstract

The benches and risers at Mormon Point, Death Valley, USA, have long been interpreted as strandlines cut by still-stands of pluvial lakes correlative with oxygen isotope stage (OIS) 5e/6 (120,000–186,000 yr B.P.) and OIS-2 (10,000–35,000 yr B.P.). This study presents geologic mapping and geomorphic analyses (Gilbert's criteria, longitudinal profiles), which indicate that only the highest bench at Mormon Point (∼90 m above mean sea level (msl)) is a lake strandline. The other prominent benches on the north-descending slope immediately below this strandline are interpreted as fault scarps offsetting a lacustrine abrasion platform. The faults offsetting the abrasion platform most likely join downward into and slip sympathetically with the Mormon Point turtleback fault, implying late Quaternary slip on this low-angle normal fault. Our geomorphic reinterpretation implies that the OIS-5e/6 lake receded rapidly enough not to cut strandlines and was ∼90 m deep. Consistent with independent core studies of the salt pan, no evidence of OIS-2 lake strandlines was found at Mormon Point, which indicates that the maximum elevation of the OIS-2 lake surface was −30 m msl. Thus, as measured by pluvial lake depth, the OIS-2 effective precipitation was significantly less than during OIS-5e/6, a finding that is more consistent with other studies in the region. The changed geomorphic context indicates that previous surface exposure dates on fault scarps and benches at Mormon Point are uninterpretable with respect to lake history.

Type
Research Article
Copyright
University of Washington

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References

Anderson, D.E., and Wells, S.G. Latest Quaternary lacustrine events of Lake Manly: A record from ten shallow cores along a 75 km transect in southern Death Valley basin. Geological Society of America Abstracts with Programs 28, (1996). 83 Google Scholar
Axen, G.J., Fletcher, J.M., Cowgill, E., Murphy, M., Kapp, P., MacMillan, I., Ramos-Velazquez, E., and Aranda-Gomez, J. Range-front fault scarps of the Sierra El Mayor, Baja California: Formed above an active low-angle normal fault?. Geology 27, (1999). 247 250.2.3.CO;2>CrossRefGoogle Scholar
Bascom, W.N. The relationship between sand size and beach-face slope. Transactions, American Geophysical Union 32, (1951). 866 874.Google Scholar
Beck, W., Donahue, D.J., Jull, A.J.T., Burr, G., Broecker, W.S., Bonani, G., Hajdas, I., and Malotki, E. Ambiguities in direct dating of rock surfaces using radiocarbon measurements. Science 280, (1998). 2132 2135.CrossRefGoogle Scholar
Blackwelder, E. Lake Manly: An extinct lake of Death Valley. Geographical Review 23, (1933). 464 471.CrossRefGoogle Scholar
Blackwelder, E. Pleistocene lakes and drainage in the Mojave region, southern California. Jahns, R.H. Geology of Southern California. (1954). California Division of Mines and Geology Bulletin 170, Sacramento. 35 40.Google Scholar
Bull, W.B. The alluvial-fan environment. Progress in Physical Geography 1, (1977). 222 270.Google Scholar
Bull, W.B., and McFadden, L.D. Tectonic geomorphology north and south of the Garlock fault, California. Doehring, D.O. Geomorphology in Arid Regions. (1977). State Univ. of New York, Binghampton. 115 136.Google Scholar
Burchfiel, B.C., Molnar, P., Zhang, P., Deng, Q., Zhang, W., and Wang, Y. Example of a supradetachment basin within a pull-apart tectonic setting: Mormon Point, Death Valley, California. Basin Research 7, (1995). 199 214.CrossRefGoogle Scholar
Curry, H.D. “Turtleback” fault surfaces in Death Valley, California. Geological Society of America Bulletin 49, (1938). 1875 Google Scholar
Dorn, R.I. A rock varnish interpretation of alluvial-fan development in Death Valley, California. National Geographic Research 4, (1988). 56 73.Google Scholar
Dorn, R.I., Jull, A.J.T., Donahue, D.J., Linick, T.W., and Toolin, L.J. Accelerator mass spectrometry radiocarbon dating of rock varnish. Geological Society of America Bulletin 101, (1989). 1363 1372.2.3.CO;2>CrossRefGoogle Scholar
Dorn, R.I., Jull, A.J.T., Donahue, D.J., Linick, T.W., and Toolin, L.J. Latest Pleistocene lake shorelines and glacial chronology in the Western Basin and Range Province, U.S.A.: Insights from AMS radiocarbon dating of rock varnish and paleoclimatic implications. Paleogeography, Paleoclimatology, Paleoecology 78, (1990). 315 331.Google Scholar
Drewes, H. (1963). Geology of the Funeral Peak Quadrangle, California, on the east flank of Death Valley. United States Geological Survey Professional Paper 413.CrossRefGoogle Scholar
Enzel, Y., Brown, W.J., Anderson, R.Y., McFadden, L.D., and Wells, S.W. Short-duration Holocene lakes in the Mojave River drainage basin, Southern California. Quaternary Research 38, (1992). 60 73.Google Scholar
Gilbert, G.K. Lake Bonneville. (1890). Google Scholar
Hooke, R.L. Geomorphic evidence for Late-Wisconsin and Holocene tectonic deformation, Death Valley, California. Geological Society of America Bulletin 83, (1972). 2073 2098.CrossRefGoogle Scholar
Hunt, C. B, and Mabey, D. R. 1966, Stratigraphy and structure Death Valley, California. U.S. Geological Survey Professional Paper 494-A.Google Scholar
Jannik, N.O., Phillips, F.M., Smith, G.I., and Elmore, D. A 35Cl chronology of lacustrine sedimentation in the Pleistocene Owens River system. Geological Society of America Bulletin 105, (1991). 1146 1159.2.3.CO;2>CrossRefGoogle Scholar
Keener, C., Serpa, L., and Pavlis, T.L. Faulting at Mormon Point, Death Valley, California: A low-angle normal fault cut by high-angle faults. Geology 21, (1993). 327 330.Google Scholar
Knott, J.R., Sarna-Wojcicki, A.M., Meyer, C.E., Tinsley, J.C. III, Wells, S.G., and Wan, E. Late Cenozoic stratigraphy and tephrochronology of the western Black Mountains piedmont, Death Valley, California: Implications for the tectonic development of Death Valley. Wright, L.A., and Troxel, B.W. Cenozoic Basins of the Death Valley Region. (1999). CrossRefGoogle Scholar
Ku, T., Luo, S., Lowenstein, T.K., Li, J., and Spencer, R.J. U-series chronology of lacustrine deposits in Death Valley, California. Quaternary Research 50, (1998). 261 275.CrossRefGoogle Scholar
Li, J., Lowenstein, T.K., Brown, C.B., Ku, T.L., and Luo, S. A 100 ka record of water tables and paleoclimates from salt cores, Death Valley, California. Paleogeography, Paleoclimatology, Paleoecology 123, (1996). 179 203.Google Scholar
Lowenstein, T.K., Li, J., Brown, C.B., Roberts, S.M., Ku, T.L., Luo, S., and Yang, W. 200 k.y. paleoclimate record from Death Valley salt core. Geology 27, (1999). 3 6.2.3.CO;2>CrossRefGoogle Scholar
McFadden, L.D., Ritter, J.B., and Wells, S.G. Use of multiparameter relative-age methods for age estimation and correlation of alluvial fan surfaces on a desert piedmont, eastern Mojave Desert, California. Quaternary Research 32, (1989). 276 290.CrossRefGoogle Scholar
Meek, N. The elevation of shorelines in Death Valley. San Bernardino County Museum Association Quarterly 44, (1997). 75 84.Google Scholar
Noble, L. F. 1926, Note on a colemanite deposit near Shoshone, Calif, with a sketch of the geology of a part of the Amargosa Valley. U.S. Geological Survey Bulletin 786.Google Scholar
Sears, D.H. Origin of Amargosa Chaos, Virgin Spring Area, Death Valley, California. Journal of Geology 61, (1953). 182 186.Google Scholar
Smith, G.I. Paleohydrologic regimes in the southwestern Great Basin, 0–3.2 myr ago, compared with other long records of global climate. Quaternary Research 22, (1984). 1 17.Google Scholar
Smith, G.I. Continental paleoclimatic records and their significance. Morrison, R.B. Quaternary Nonglacial Geology: Conterminous U.S. (1991). Geol. Soc. Am, Boulder. 35 41.Google Scholar
Smith, G. I. (1991b). Stratigraphy and chronology of Quaternary-age lacustrine deposits.. In Quaternary Nonglacial Geology: Conterminous U.S. Morrison, R. B., Ed., pp. 339345. Geol. Soc. Am. Boulder, CO.Google Scholar
Troxel, B.W. Significance of Quaternary fault pattern, west side of Mormon Point turtleback, southern Death Valley, California; A model for listric normal faults. Troxel, B. Quaternary Tectonics of Southern Death Valley, California Field Trip Guide. (1986). B. W. Troxel, Shoshone. 37 40.Google Scholar
Trull, T.W., Brown, E.T., Marty, B., Raisbeck, G.M., and Yiou, F. Cosmogenic 10Be and 3He accumulation in Pleistocene beach terraces in Death Valley, California, U.S.A.: Implications for cosmic-ray exposure dating of young surfaces in hot climates. Chemical Geology 119, (1995). 191 207.CrossRefGoogle Scholar
Watchman, A. A review of the history of dating rock varnishes. Earth-Science Reviews 49, (2000). 261 277.CrossRefGoogle Scholar
Wells, S.G., Bullard, T.F., Menges, C.M., Drake, P.G., Karas, P.A., Kelson, K.I., Ritter, J.B., and Wesling, J.R. Regional variations in tectonic geomorphology along a segmented convergent plate boundary, Pacific coast of Costa Rica. Geomorphology 1, (1988). 239 265.CrossRefGoogle Scholar
Wernicke, B. Low-angle normal faults in the Basin and Range Province: Nappe tectonics in an extending orogen. Nature 291, (1981). 645 648.CrossRefGoogle Scholar