Abstract

Silver Lake, located just north of Baker, San Bernardino County, California, has undergone dramatic hydrologic changes over the past 15,000 years. For this thesis, semi-quantitative estimates of ostracod abundances serve as a hydrogloic proxy and are as used to infer past hydrolgic changes. The data suggest a three-step trend from wet late Glacial to a less wet early Holocene to a dry late Holocene. Conditions became unfavorable for ostracod growth as Silver Lake transitioned from a  perennial lake to its present day playa lake state. This long-term change reflects the transition from the cold wet late Glacial to the warm dry Holocene. This long-term change is likely related to insolation forcing of winter and summer precipitation variability and their respective influences on Mojave River run-off. Future work will analyze the oxygen isotopic values of these ostracods to determine changes in the lake water's isotopic history.