The region investigated in this study is situated in the Central and Northern Santos Basin, covering the areas ranging from Mexilhão to the deep and ultra deep water. RADARSAT-1 full resolution images were processed using a textural analysis based proprietary approach. The results were integrated with meteorological and oceanographic ancillary information in a geographic information system environment.
The characterization of the oil seeps widespread around the Central and Northern areas, close to Mexilhão, BMS-400, BMS-500 and around the BMS-9 and BMS-10 confirms the presence of active and leaking petroleum systems associated with salt diapirs present in the area, and is an indicator of the present-day hydrocarbon generation, migration and accumulation, therefore reducing the exploration risk in the area.
Piston Core Survey in the BM-S-31 Block, Santos Basin, Offshore Brazil
Piston Core50 Piston cores were obtained from points located using 3D geophysical data integrated with geological information. Core samples were analyzed by microbial and geochemical screening type analyses such as C1-C5 Headspace Gas, C1-C5 Sorbed Soil Gas (SSG), Total Scanning Fluorescence (TSF), hydrocarbon-specific microbes (MOST) and Gas Chromatography of C15+ (GC). Moreover, samples were analyzed by High Resolution Gas Chromatography/Mass Spectrometry (GC/MS) of saturates and aromatics compounds and diamondoids.
The final results of these analyses were compared to regionally-produced oils and other piston core results obtained in Brazilian Sedimentary Basins. The integration of all data indicates the presence of liquid thermogenic hydrocarbon in cores collected throughout the study area confirming therefore oil and gas seeps derived from very deep pre-salt and oil window post-salt source rocks. Such result is a real proof of the existence of both a marine and lacustrine petroleum system, and allows exploration to be focused on specific plays and prospects.