Patent ID: 6462549
Filing Date: 2002-10-08
Classification: G01V

Abstract:
A method of determining the location of a microseismic event comprising the steps of:receiving electromagnetic data representing electromagnetic energy traveling through the earth that has been measured by an electromagnetic sensor, at least some of the electromagnetic energy being caused by a microseismic event that consists primarily of rock fracturing or activation of existing rock fractures; receiving seismic data representing vibrations in the earth caused by said microseismic event, the seismic data being measured using plurality of ground motion sensors; estimating the time at which said microseismic event occurred based at least in part on the time at which electromagnetic energy caused by the microseismic event is received by the electromagnetic sensor; and determining the location of said microseismic event using the estimated time at which the microseismic event occurred and the time at which the earth vibrations caused by the microseismic event arrived at the ground motion sensors.