Brutus Late Life Redevelopment: An Integrated Field Study using Legacy 4D Seismic and Geochemical Analysis

Connectivity between reservoir compartments in the Brutus Field is difficult to predict despite extensive availability of conventional 3D seismic, and historic production and pressure data, resulting in risk and uncertainty in planning future late-life development wells. It is because of this that more sophisticated tools are needed to unravel the complex structural and stratigraphic framework in this mature field, leading to an integrated approach to field development using both qualitative legacy 4D seismic data and geochemical fingerprinting data obtained as part of the reservoir surveillance activities. The 4D signals observed on the time lapse analysis of a 2012 ocean bottom node (OBN) dataset compared to a pre-production, 1999 narrow azimuth (NAZ) streamer dataset appear consistent with production, pressure and geochemical data. This integrated interpretation approach supports the probability of several remaining undrained reservoir compartments that are being targeted in the upcoming Brutus drilling campaign. One of these compartments, the J2 Reservoir U2 fault block, will be the focus of this paper.