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Wisconsin Glaciation of the Sierra Nevada (79,000-15,000 yr B.P.) as recorded by rock flour in sediments of Owens Lake, California

Quaternary Research

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DOI: 10.1006/qres.2000.2183

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Abstract

Chemical analyses of the clay-sized fractions of 564 continuous sediment samples (200-yr resolution) from composite core OL90/92 allow quantification of an abundance of glacial rock flour. Rock flour produced during glacier advances is represented by clay-sized plagioclase, K-feldspar, and biotite in homogeneous internal composition. The abundance of rock flour is deemed proportional to the intensity of glacies advances. Age control for the composite section is provided by combining previously published radiocarbon dates on organics, U/Th dates on ostracode shells, and U/Th dates on saline minerals from nearby Searles Lake correlated to OL92 by pollen. The rock flour record displays three levels of variability: (1) a dominant one of about 20,000 yr related to summer insolation and precipitation; (2) an intermediate one of 3000-5000 yr, perhaps related to North Atlantic Heinrich events; and (3) a minor one of 1000-2000 yr, perhaps related to North Atlantic thermohaline-driven air-temperature variation. ?? 2001 University of Washington.

Additional Publication Details

Publication type:
Article
Publication Subtype:
Journal Article
Title:
Wisconsin Glaciation of the Sierra Nevada (79,000-15,000 yr B.P.) as recorded by rock flour in sediments of Owens Lake, California
Series title:
Quaternary Research
DOI:
10.1006/qres.2000.2183
Volume
55
Issue:
1
Year Published:
2001
Language:
English
Larger Work Type:
Article
Larger Work Subtype:
Journal Article
Larger Work Title:
Quaternary Research
First page:
14
Last page:
24
Number of Pages:
11