Fault reactivation analysis of the Cleaver Bank High based on 3D seismic Data

Abstract

The dominant fault trends in the southern part of Dutch offshore are NW-SE and NE-SW, which formed during the Paleozoic. During post-Carboniferous tectonic phases, only few new faults formed at Rotliegend level, but the pre-existing basement faults were reactivated repeatedly and penetrated into Rotliegend sediments. Under different tectonic regime and stress direction, different trends of basement faults were reactivated from different angles. The high quality of 3D Seismic data allows for an improved fault analysis in Cleaver Bank High, which is located in the central part of Dutch offshore. Five distinct fault trends were recognized at Base Zechstein level, including NW-SE, NNW-SSE, WNW-ESE, NE-SW and N-S. This study determined when the faults were reactivated since the Permian, and found oblique reactivation on pre-existing faults in the study area. This information leads to a better understanding on the structural development. Reactivation of old faults resulted in the formation of new petroleum traps or the destruction of originally exited ones. So the improved understanding of the fault reactivation also helps to decrease the risk of petroleum exploration.