Figure 1.
Architecture of gravity-driven thrust systems, based on the Pará-Maranhão basin, offshore Brazil (Zalan, 2005). The pre-kinematic section is shown in green and has been stacked up into a deepwater thrust belt on the lower slope. Sedimentation has continued (tan-yellow tones) and eventually buried the thrust belt. These syn-kinematic deposits are ponded in fault-related basins within the extensional domain, upslope from the thrust belt. The sediments show characteristic geometry of growth strata, thickening toward the main extensional faults and forming off-lapping depositional wedges that become progressively younger up the slope. Cumulative stratal shortening in the contractional domain should balance the net extension, here shown by the separation of pre-kinematic strata along the main detachment.