| Summary: | Salt Core DV93 -1, from Badwater Basin in California's Death Valley, spans the past 192 ka. An analysis of fossil palynomorphs from 151.8 m (ca. 166 ka) to 103.5 m (ca. 114 ka) delimits four pollen zones. Zone 1, the "cheno -am" zone (151.8 to 143.5 m depth, 166 -154 ka), contains high percentages of Chenopodiaceae /Amaranthus pollen, and correlates with marine Oxygen Isotope Stage (OIS) 7. Zone 2, the juniper zone (143.5 to 117.3 m, 154 -124 ka), correlates with OIS 6 and contains high percentages of Cupressaceae pollen and low percentages of Ambrosia pollen. A simultaneous drop in juniper and increase in oak (Quercus) pollen, followed by replacement of Artemisia with Ambrosia, occurs at the Zone 2 /Zone 3 (oak zone) boundary (124 ka), corresponding to OIS Termination II warming. Zone 4, the Asteraceae zone (108.8 to 103.5 m, 119 -115 ka), contains higher percentages of Asteraceae and cheno -am pollen, indicating further warming.
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