Pore pressure monitoring in a chalk gas reservoir using surface-wave velocity variations

Abstract

Measurements of pore pressure variations contain important information for the production of hydrocarbon reservoirs. Here, we couple surface-wave velocity changes directly to pore pressure change using sensitivity kernels. Using these kernels for realistic pore pressure changes in the Harlingen chalk gas reservoir, we modelled yearly Rayleigh-wave velocity changes. The velocity variations appear sufficiently large to be detectable on a yearly basis using passive image interferometry. This implies that, for specific formations, field-wide pore pressure monitoring is feasible with continuous seismic noise recordings at the surface.