Sedimentary biomarker and isotopic indicators of the paleoclimatic history of the Walker Lake basin, western Nevada
نویسنده
چکیده
-Walker Lake, a terminal saline lake in western Nevada, has experienced major fluctuations in its water level due to changes in the regional climate during Quaternary times. As part of a paleoclimatological study of western Nevada, we have investigated organic matter 6 ~3C and C/N values and lipid biomarker contents of sediments deposited at various periods over the past 150 thousand years of lake history. Surficial sediments from two cross-lake transects contain mostly lake-derived organic matter. Diagenetic losses of organic matter are evident in deeper sediments, and the proportion of aquatic and terrigenous organic materials changes in response to variations in preservational factors. Source identification of organic matter is complicated by the probability that Walker Lake has experienced desiccation at various times in its history which impacts the degree of preservation of organic substances.
منابع مشابه
Evaluating sedimentary geochemical lake-level tracers in Walker Lake, Nevada, over the last 200 years
Walker Lake, a hydrologically closed, saline, alkaline lake located along the western margin of the Great Basin of western United States, has experienced a 77% reduction in volume and commitment drop in lake level as a result of anthropogenic perturbations and climatic fluctuations over the last century. The history of lake-level change in Walker Lake has been recorded instrumentally since 1860...
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