| Summary: | American Geophysical Union Fall Meeting, 10-14 December 2018, Washington D.C. We present seismic data collected in 2018 of the structure of the opening of the central Atlantic Triassic to early Jurassic rifted margin, and of the Upper Jurassic to Early Cretaceous north Atlantic Mesozoic rift basins and rifted margins. We present crustal-scale images with a 6-km-long streamer, and new coincident wide-angle seismic data with ~10-km-spaced OBs across several transects in regions where previous work is from the 80 and mid 90's. New images of the Galicia Interior Basin (GIB) display an asymmetric tectonic and crustal structure, and prominent thinning at the basin center. The basin is characterized by large-scale normal faults that are laterally bounded by transfer fault structures. Fault-block structure indicates that GIB and the Deep Galicia Margin (DGM) -where break up occurred- where kinematically linked. New images of the Tagus Abyssal Plain display the transition from continental crust to exhumed mantle and, crossing the J-anomaly ridge, to the oceanic crust, providing clues of the interaction between magma and tectonics. Finally, seismic data from NW Africa display a rather different structure, with upper Triassic evaporite-diapirs extruding from fault-blocks of highly extended possibly continental crust, with Early Jurassic (drilled) synrift deposits in tilted blocks Peer Reviewed
|
|---|