GSA Annual Meeting in Phoenix, Arizona, USA - 2019

Paper No. 279-2
Presentation Time: 9:00 AM-6:30 PM

GEOCHEMICAL CONSTRAINTS ON THE PROVENANCE OF EDIACARAN–CAMBRIAN SEDIMENTARY ROCKS FROM THE SOUTHWESTERN MARGIN OF LAURENTIA


WEBB, L.C.1, NELSON, L.L.2, HODGIN, E.B.3 and SMITH, E.F.1, (1)Department of Earth and Planetary Sciences, Johns Hopkins University, 3400 N Charles Street, Baltimore, MD 21218, (2)Department of Earth and Planetary Sciences, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218, (3)Department of Earth and Planetary Sciences, Harvard University, 20 Oxford Street, Cambridge, MA 02138

The break-up of the supercontinent Rodinia is often mechanistically linked to coeval changes in Neoproterozoic–Cambrian life, climate, and surface conditions, yet the timing and nature of this tectonic evolution remain debated topics. Calibration of the rift to drift transition along the western (present-day coordinates) margin of Laurentia has remained particularly contentious with suggestions ranging over a hundred million years from the early Ediacaran to the middle Cambrian. This study aims to use geochemical data of fine grained clastic rocks from late Ediacaran–Cambrian stratigraphic sections in southwestern North America to understand temporal changes in sedimentary provenance that may be associated with the weathering of rift-related volcanic rocks along this margin.