COOPER, MIKE,ANDY O'DONOVAN, ANDY LOS, RONNIE PARR, and GARY NEVILLE, BP - Amoco, Aberdeen, UK

Abstract: 4-D Seismic : Active reservoir management of the Foinaven and Schiehallion Fields, West of Shetland

The Foinaven and Schiehallion Fields were discovered in the early nineties primarily due to the bright amplitude response of the seismic data to the presence of hydrocarbon-bearing sands. Both fields were rapidly appraised during 1994 and 1995 with the 3D seismic data being used to predict the hydrocarbon pore thickness of the reservoir.The seismic data has been fundamental for development drilling and building the reservoir model. Production started from the fields in 1997 and 1998.

A joint project, Foinaven Active Reservoir Management (FARM), was set up by BP, Shell and Geco-Prakla to exploit the seismic response in monitoring the movement of fluids through the reservoir during production. The area of investigation is initially confined to the southernmost segment of the Foinaven Field. Production began from 2 subsea horizontal wells in November 1997. Seismic repeatability is enhanced by the installation of permanent ocean bottom cables, allowing the comparison of surface tow and ocean bottom data for 4-D analysis. Pre and post production data were acquired using both techniques.

On Schiehallion a parallel investigation was carried out to investigate the repeatability of surface tow data. Seismic surveys were acquired in 1993 and 1996. The 2 surveys were re-processed together in 1998 in an attempt to produce similar data sets suitable for time-lapse analysis.

The projects on both fields have already added value to the developments and significantly progressed the understanding of 4-D seismic techniques.

AAPG Search and Discovery Article #90923@1999 International Conference and Exhibition, Birmingham, England