Seismic monitoring of carbonate reservoirs in a desert environment has remained one of the final time-lapse frontiers due to the low 4D signal produced by carbonates combined with potentially high 4D noise resulting from complex and changing near-surface geology. Here we show how a hybrid acquisition system utilizing buried receivers, combined with time-lapse processing, can achieve highly repeatable data capable of detecting weak 4D signal. For surveys acquired under similar climatic conditions, average NRMS values of 2–5% have been observed, enabling detection of small reservoir signal related to fluid injection in a carbonate reservoir. Small increases in 4D noise when comparing surveys acquired during different seasons masks the 4D signal and remains a challenge. The use of multiple baseline surveys can help overcome this issue. Monitoring larger areas will require bigger receiver spacing than the 50 m grid used here, but receiver decimation tests show that unacceptable increases in 4D noise result from sparser grids. Novel designs using DAS technology may be the key to more efficient acquisition systems.
Presentation Date: Monday, September 16, 2019
Session Start Time: 1:50 PM
Presentation Start Time: 4:45 PM
Location: 225B
Presentation Type: Oral
