The Feasibility of Permanent Land Seismic Monitoring with Buried Geophones and Hydrophones

A comprehensive onshore seismic experiment was conducted in Saudi Arabia to evaluate various configurations for seismic monitoring in a desert environment. A line of 80 receiver stations was deployed comprised of both geophones and hydrophones permanently cemented in the boreholes at four different depth levels from 0 to 30 m. This study focuses on the analysis of data acquired using a surface vibrator source. Due to the challenging near-surface conditions and poor signal-to-noise ratio observed on the pre-stack data, a dense source grid was acquired with the surface vibrator. Designing a processing sequence that was optimized for imaging and repeatability was essential. The best stack image and repeatability was obtained using data from the receivers located at 30 m. Post-stack repeatability of around 20-25 % NRMS was obtained over a large portion of the line. We observed additional improvements in imaging when using dual-sensor summation by combining the geophone and hydrophone data. In addition, virtual source redatuming was performed, which produced images with an increased continuity of some of the targeted events. Further work to fully understand the limits and opportunities of land seismic monitoring is in progress.