Expressions of shallow gas in the Netherlands North Sea

Abstract Surface and sub-surface expressions of shallow gas in the Netherlands part of the southern North Sea are described, using standard E&P 2D and 3D seismic surveys, as well as higher frequency acoustic surveys. Surface expressions observed are pockmarks, which are geomorphologic features at the seabed indicative for venting of gas, and cemented sandstones. The subsurface expressions found comprise both phenomena indicating efficient trapping of gas in reservoir sands, such as shallow bright spots and flat spots, and phenomena, which are indications of migration or leakage to the seab... Mehr ...