Virtual source method applied to horizontal well and cross‐well geometries

Abstract

The virtual source method [1, 2], an interferometry‐based technique for data driven redatuming using cross‐correlation of the recorded wavefield, is a rapidly growing technology for imaging and monitoring below complicated overburden. For VSP (non‐horizontal wells) and OBC acquisition geometries, merits of the virtual source method for reservoir monitoring have been demonstrated in previous work [3]. This concept can also be applied to crosswell geometries [4], whereby a crosswell survey is simulated by shooting a line of surface shots and recording these simultaneously into receiver arrays placed in two boreholes. In this virtual crosswell survey, the receiver array in either of the boreholes is turned into an array of virtual sources that synthesizes data kinematically equivalent to real crosswell data, as we demonstrate using field data acquired onshore US. Such virtual crosswell survey should be useful for enhanced reservoir characterization and monitoring under complex overburden for moderate interwell distances.