Interferometric reservoir monitoring with a single passive source

Abstract

Changes in the subsurface can be imaged by subtracting seismic reflection data at two different states, one serving as the initial survey or base, and the second as the monitor survey. Conventionally, the reflection data are acquired by placing active seismic sources at the acquisition surface. Alternatively, these data can be acquired from passive sources in the subsurface, using seismic interferometry. Unfortunately, the reflection responses as retrieved by seismic interferometry inherit an imprint of the passive source distribution. Therefore, monitoring with seismic interferometry requires high passive source repeatability, which is often not achievable in practice. We propose an alternative, by using active seismic data for the base survey and a single passive source for the monitor survey. By constraining the radiation pattern of the (active) base survey according to the characteristics of the (passive) monitor survey, we succeed to extract time-lapse response in the image domain. The proposed method is illustrated with numerically modeled data.