GSA 2020 Connects Online

Paper No. 173-1
Presentation Time: 10:05 AM

CRYOGENIAN RIFTING IN DEATH VALLEY, CALIFORNIA (USA)


NELSON, Lyle L.1, SMITH, Emily F.1, HODGIN, Eben B.2, CROWLEY, James L.3, SCHMITZ, Mark D.3 and MACDONALD, Francis A.4, (1)Department of Earth and Planetary Sciences, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218, (2)Department of Earth and Planetary Sciences, Harvard University, 20 Oxford St, Cambridge, MA 02138, (3)Department of Geosciences, Boise State University, Boise, ID 83725, (4)Department of Earth Science, University of California Santa Barbara, Santa Barbara, CA 93109

Death Valley (California, USA) hosts iconic stratigraphic records of Neoproterozoic rifting and Cryogenian snowball Earth glaciations, but the lack of direct geochronological constraints has permitted a variety of correlations and age models. Here, we report two precise zircon U-Pb isotope dilution–thermal ionization mass spectrometry dates for the Kingston Peak Formation, which demonstrate correlations to the Sturtian and Marinoan glaciations and contribute to the global calibration of their respective durations. When integrated with stratigraphic data sets from across the region, these dates calibrate the development of overlapping unconformities through episodic and spatially variable structural uplift and exhumation. This constrains intervals of local rift-related tectonism, magmatism, and subsidence that can be compared to the broadly coeval records of supercontinent break-up along the western Laurentian margin.