Incremental Gains from Revisiting 4D Timeshifts on Forties
P.S. Rowbotham, E.C. Colledge, P.T. Rose, L.A. Singer and G.W. Byerley
Event name: First EAGE Workshop on Practical Reservoir Monitoring
Session: Realising the Value of Data
Publication date: 06 March 2017
Info: Extended abstract, PDF ( 1.37Mb )
Price: € 20
The Forties Field has a rich history of 4D seismic for selecting and de-risking infill drilling targets. Improvements in 4D acquisition and processing are leveraged by regularly reprocessing vintage seismic datasets. These improvements allow new target concepts to be developed, but also create new challenges in interpretation. Warping of time-lapse datasets prior to differencing can reduce 4D noise and enhance 4D amplitude signal for interpretation. However, warping can also damage 4D signal. An understanding of the behaviour of warping on the 4D data through numerical modelling and forward wedge modelling has helped to show why 4D warping can result in disagreement with the well production history. Parameterisation testing produces an improved differentiation between 4D noise and signal, and a better timeshift interpretation volume.