Seismic low‐frequency effects from fluid‐saturated reservoir

Abstract

The normal incidence of Pelastic wave reflected from a thin porous dry and water saturated layer is considered. The effect of stronger reflections and travel time delays from water saturated layer is observed at low frequencies. We compared the results of laboratory modeling with “frictional-viscous” theoretical model and found that low (< 5) values of attenuation parameter Q and its approximate proportionality to frequency can explain the effect. The values of Q were determined in a separate experiment using recordings of a transmitted field for a thick porous layer, where water saturated layer had attenuation about two times higher then in a dry layer. These findings can be used for detecting and monitoring liquid saturated areas in thin porous layers.