Time‐depth converted interpretation of regional seismic maps, offshore southeast Brazil

Abstract

Regional seismic interpretation mapping of the pre-stack time migrated data produced seven key sequence boundary maps: Sea-floor, Intra-Oligocene, Top Cretaceous, Top Albian, Top Salt, Base Salt and Top Basement. Iso-time maps were subsequently constructed for the major tectono-stratigraphic mega sequences: syn-rift-lacustrine, transitional-transgressive and drift-open marine. Significant structural elements in each of these time maps are herein described and discussed. The depth conversion of each regional map adds considerably to the structural interpretation. Most of the regional structural features are in deep-water; hence the bathymetry correction itself affects the visualization of structures. It is well known that residual misties needs adjust the mapping of depth along non-dip lines. Hence, our depth conversion of deep-water maps was adjusted for these. Several of the dip-lines utilized were pre-stack depth migrated, but mostly with seismically derived velocities over the large deep/ultra-deep-water realm.