INVERSION OF EASTERN MIDCONTINENT RIFT DURING RODINIA BREAK UP AND EFFECTS ON NORTH AMERICAN SEDIMENT ROUTING

Reconstructing the location and timing of basement topography in continental interiors is critical to understand the tectonic and geodynamic processes that modify stable cratonic lithosphere; however, these regions commonly have a sparse and poorly accessible geologic record making this a challenging task. New detrital zircon U-Pb provenance data (n=19) derived from subsurface core samples from the Michigan Basin, USA, tracks Paleozoic sediment routing patterns within the relatively small basin, a region ~ 400 km x 300 km. The results reveal intra-basin heterogeneity in provenance that persists through at least the Middle Devonian. U-Pb dates show three distinct provenance signatures that are determined by sediment deposition location within the basin: regions dominated by sediment from local exposures of the Granite/Rhyolite Province, regions with sediment from the northern Archean craton, and a single area dominated by sediment from western North America. . The segmentation of provenance signatures suggests basement topography altered sediment routing patterns in the Michigan Basin and may have been an important feature for continental-scale drainage organization. The provenance patterns observed in this study follow boundaries consistent with the eastern arm of the ca. 1 Ga. Midcontinent Rift with implications for timing and topographical manifestations of rift inversion. Specifically, sediment routing patterns support the maintenance of basement topography consistent with rift inversion during the final breakup of Rodinia. Subsidence analysis provides context for these observations. Although this work focuses on results from the sedimentary record, the observations provide spatio-temporal constraints for the rise and decay of intracratonic topography informative to a wide range of geoscientists.