Structural Modelling for Shenzi Field Development

Abstract

The Shenzi Field is a well-known sub-salt play located in the northern Gulf of Mexico Basin, production in the field is mainly from the Early Miocene DD, EE and FF turbidite reservoirs, which are generally found between 23,500–28,500 feet TVD. A petrophysical study has been carried out showing that the three reservoirs that vary in thickness from 20–180 feet have an average porosity and permeability of 21% and 500–700md, respectively.

Structural interpretation was based on pre-stack, depth migrated, rich azimuth 3D seismic data acquired in 2006. The quality of the seismic data was limited due to the presence of the salt body. A high level of uncertainty was involved when identifying the top and base of reservoir sands, since the seismic vertical resolution is around 150ft. Interpretation of the horizons was controlled by well markers and the deeper Top Oligocene reflector associated with a high impedance contrast limestone package. Halokinesis has led to the generation of a complex structure, having normal and reverse faults with Jurassic detachment planes. Analysis of pressure data revealed that these faults are most likely sealing. Three main isolated blocks were recognized and supported by MDT data, indicating three different oil-water contacts in the area.

AAPG Datapages/Search and Discovery Article #90192 © 2014 European Regional Conference and Exhibition, Barcelona, Spain, May 13-15, 2014