TY - JOUR
T1 - Late quaternary environmental changes in the upper Las Vegas valley, Nevada
AU - Quade, Jay
N1 - Funding Information:
C. Vance Haynes and Martin Mifflin advised me at all stages of this study. To them both I am grateful. My thanks also to W. Pratt for analyses of the mollusks and to R. Thompson for that of the pack-rat middens. The University of Arizona provided laboratory facilities and the Desert Research Institute drafting and typing services. Funding for this study comes from the Graduate Research Fund of the University of Arizona. NSF Grant ER-8216725 awarded to C. V. Haynes. the Desert Research Institute, and the U.S. Geological Survey.
PY - 1986/11
Y1 - 1986/11
N2 - Five stratigraphic units and five soils of late Pleistocene to Holocene age crop out in dissected badlands on Corn Creek Flat, 30 km northwest of Las Vegas, Nevada, and at Tule Springs, nearer to Las Vegas. The record is dominantly fluvial but contains evidence of several moister, marsh-forming periods: the oldest (Unit B) dates perhaps to the middle Wisconsin, and the more widespread Unit D falls between 30,000 and 15,000 yr B.P. Unit D therefore correlates with pluvial maximum lacustrine deposits elsewhere in the Great Basin. Standing water was not of sufficient depth or extent during either period to form lake strandlines. Between 14,000 and 7200 yr B.P. (Unit E), standing surface water gradually decreased, a trend also apparent in Great Basin pluvial lake chronologies during the same period. Groundwater carbonate cementation and burrowing by cicadas (Cicadae) accompany the moist-phase units. After 7200 yr B.P., increased wind action, decreased biotic activity, and at least 25 m of water-table lowering accompanied widespread erosion of older fine-grained deposits. Based on pack-rat midden and pollen evidence, this coincides with major vegetation changes in the valley, from sagebrush-dominated steppe to lower Mohave desertscrub.
AB - Five stratigraphic units and five soils of late Pleistocene to Holocene age crop out in dissected badlands on Corn Creek Flat, 30 km northwest of Las Vegas, Nevada, and at Tule Springs, nearer to Las Vegas. The record is dominantly fluvial but contains evidence of several moister, marsh-forming periods: the oldest (Unit B) dates perhaps to the middle Wisconsin, and the more widespread Unit D falls between 30,000 and 15,000 yr B.P. Unit D therefore correlates with pluvial maximum lacustrine deposits elsewhere in the Great Basin. Standing water was not of sufficient depth or extent during either period to form lake strandlines. Between 14,000 and 7200 yr B.P. (Unit E), standing surface water gradually decreased, a trend also apparent in Great Basin pluvial lake chronologies during the same period. Groundwater carbonate cementation and burrowing by cicadas (Cicadae) accompany the moist-phase units. After 7200 yr B.P., increased wind action, decreased biotic activity, and at least 25 m of water-table lowering accompanied widespread erosion of older fine-grained deposits. Based on pack-rat midden and pollen evidence, this coincides with major vegetation changes in the valley, from sagebrush-dominated steppe to lower Mohave desertscrub.
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U2 - 10.1016/0033-5894(86)90094-3
DO - 10.1016/0033-5894(86)90094-3
M3 - Article
AN - SCOPUS:0022860859
SN - 0033-5894
VL - 26
SP - 340
EP - 357
JO - Quaternary Research
JF - Quaternary Research
IS - 3
ER -