Invaluable Role of Pressure Data in Reservoir Management: A Deepwater Field Experience

Abstract

This paper reviews and shares lessons on the critical role of subsurface pressure data in the successful management of Agbami Field. Agbami is a Chevron operated deepwater asset located in 4,800 ft of water with a combination of water and gas injection development strategy. Production commenced in 2008 and has remained plateau at over 240 MBOPD. The field hosts intelligent well completions with capability of real time pressure data acquisition. In addition to this suite of pressure data from downhole gauges, wireline and LWD tools have been deployed to acquire valuable pressure data in the field. Several applications of reservoir pressure data in Agbami Field are shared in this paper. First, pressure data was used in establishing connectivity between a water injector and an oil producer in a rather poor seismic amplitude area. This led to significant savings from drilling another injector to support the 20,000 BOPD producer. Second, a reservoir originally interpreted as "virgin", which was later found to be depleted is described. This reservoir re-characterization resulted in over 20% increase in oil recovery. In another case, oil-water contact in a major reservoir was estimated using wireline pressure data, resulting in the booking of additional proved volumes. One key lesson is to always integrate pressure data with other data in the field. This integration often improves the asset team's understanding of the reservoir. A best practice is to ensure that all pressure data is quality checked before use to avoid erroneous interpretation. The availability of subsurface pressure data from different tools, at different gauge depths and at different times, poses a common challenge: RM practitioners who utilize these data need to ensure proper correction is done before field application.