Abstract
Currently ADNOC is conducting the world's largest continuous 3D seismic acquisition campaign of approximately 90 000km2 with the aim of covering the entire Abu Dhabi emirate subsurface (both onshore and offshore) with 3D seismic. The main objective of this campaign is to provide high quality seismic data to explore conventional and unconventional resources. The new 3D covers areas that were under-explored in the past and is of excellent quality to apply advanced technologies for interpretation and reservoir characterization. The new 3D seismic data has high-trace density, broadband frequency content, full-azimuth and long offsets, which provides paramount information for detailed subsurface imaging and characterization of complex reservoirs.
This study is focused on a 3D land seismic survey recently acquired that is currently at the time and depth imaging stage. The early-out volumes obtained from processing consist of valuable preliminary data that can be used to infer some possible exploration prospectivity features while final processing is still ongoing.
A significant benefit of the pre-stack depth migration (PSDM) method is the construction of a detailed anisotropic subsurface velocity property model. Therefore, it accounts for lateral velocity variations, which are related to geological features especially attractive to explorationists, and has a more accurate overburden representation than historical time imaging workflows. Herein, we present some examples on how the 3D PSDM volume reveals more confidence in geological features that are not so clear in a pre-stack time migrated (PSTM) volume. The preliminary results indicate how shallow hydrocarbon presence can interfere with the PSDM velocity model and how it can be solved to reveal possible exploration potential in deeper sections.
