DRILLING METHOD AND APPARATUS

摘要

A method of locating a drilling apparatus and/or a borehole in a subterranean region, comprising the steps of: (A) transmitting seismic waves into the subterranean region during a subterranean drilling operation, the seismic waves being transmitted from a location remote from said drilling apparatus; (B) detecting a seismic response from said drilling apparatus or borehole; and (C) comparing said detected response with predetermined seismic survey data of said subterranean region to determine the location of said apparatus or borehole.