Investigating the Early Pleistocene Seismite and Environment of the Ancient Waucobi Lake Beds in Owens Valley, CA
Abstract
A 2.4-2.5 Ma seismite layer, ~1.5 meters thick, has been identified in the Plio-Pleistocene Waucobi Lake Beds in Owens Valley, CA. The seismite is immediately overlain by a distinct change in lacustrine facies from alkaline conditions suggested by the zeolite, phillipsite, to fresh water conditions suggested by diagenetic clays such as illite and montmorillonite. This facies change implies a deepening of Waucobi Lake at the same time that Searles Lake, 235 km to the south, underwent desiccation. Since both lakes are believed to have been an integral part of the drainage pathway of the paleo-Owens River, we speculate that the tectonic event which triggered the seismite also reconfigured the drainage of the paleo-Owens River such that more water was stored in the Waucobi basin and flow to Searles Lake was reduced or terminated.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2012
- Bibcode:
- 2012AGUFMPP11A2002D
- Keywords:
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- 1041 GEOCHEMISTRY / Stable isotope geochemistry;
- 1637 GLOBAL CHANGE / Regional climate change;
- 3617 MINERALOGY AND PETROLOGY / Alteration and weathering processes;
- 8169 TECTONOPHYSICS / Sedimentary basin processes