Dymamics of salt dome exhumation on the ocean floor, focusing on Santos basin offshore Brazil

Abstract

Salt domes (diapirs) are one of the central structures in hydrocarbon exploration. They form in the subsurface and occasionally host reservoirs from underneath. Fractures and faults formed during the upward motion of the salt may lead to leakage of gas/fluids towards the seafloor. In theory, the dynamics of fracturing could have been studied from the layers covering the salt dome. However, these layers are pushed aside while the dome advances upwards and the evidence is lost. Little is known about the real-time processes that shape a dome while it is exposed at the seafloor, therefore our understanding of salt diapirism relays on the geology on their flanks (from subsurface data) as well as from outcrops inland areas. In July 2016, we (Mahiques and Schattner) participated in a research cruise to the diapir site on the Atlantic ocean floor offshore Santos, Brazil. We collected new geological and geophysical data that sheds new light on salt domes uprising. Preliminary results provide a detailed image of salt dome exposure at the ocean floor and allow distinguish between three main stages before, during and after the exhumation of the salt. In this proposal, we seek funds that will allow us to analyze the data together and publish the research in a top journal. The collaboration between Mahiques and Schattner began in 2014. Since then we published together two papers in leading journals and presented them in international conferences. We intend to continue this fruitful collaboration and publish the study of the salt domes proposed here. (AU)