Syn-rift Sedimentary Provenance during Progressive Rifting along the Eastern North American Margin, U.S.A.

Our understanding of progressive rifting along continental margins and the processes leading to lithospheric break-up has greatly improved over the past decades. These advances allow for reconstructions of the kinematic, temporal, and thermal evolution of rifted margins. However, limited progress has been made in the understanding of the topographic evolution in response to progressive rifting and break-up nor the sedimentary source-to-sink dynamics of magma-poor or -rich rifted margins. The Triassic/Jurassic syn-rift basins along the Eastern North American Margin (ENAM) span the diffuse rifting, initial necking, and hyperextension phases and record the syn-rift sedimentary provenance evolution and the interplay between crustal thinning and transition to magmatic break-up. These ENAM rift basins, stretching from Canada to Florida, record the early tectonostratigraphic and 3-D geometric evolution of continental rifting, including ~30 Myr of syn-rift deposition prior to Central Atlantic Magmatic Province (CAMP) magmatism and subsequent continental break-up. The non-marine lithofacies of the Newark Supergroup comprise the initial syn-rift strata of the individual basins along the ENAM. Carnian-Sinemurian deposits occur in a series of half grabens with predominately east-dipping basin bounding faults controlled by pre-existing Appalachian structural grain. Here we present extensive new detrital zircon (DZ) and detrital apatite (DA) U-Pb results from Carnian-Sinemurian syn-rift sedimentary rocks of the Newark and Culpeper basins and reconstruct sediment dispersal pathways during progressive rifting and magmatism (CAMP). Distinct DZ and DA provenance shifts are observed in the Newark and Culpeper basins. This indicates two major paleodrainage reconfigurations occurred during progressive rifting along the ENAM due to (1) Early Norian rift flank uplift and crustal necking and (2) regional and local uplift associated with CAMP at the Triassic/Jurassic boundary. This shows the ability to track the surface response of progressive rifting and onset of magmatic break-up with DZ and DA provenance tools. These results also demonstrate the power of DA U-Pb analyses in unraveling provenance shifts, missed in DZ data, due to the ability to recognize both high and medium-T tectono-magmatic events.