METHOD FOR MONITORING A MULTI-LAYERED SYSTEM

摘要

A method for monitoring a multi-layered system below a surface comprising a slow layer and a fast layer; the method comprising: transmitting one or more seismic waves fr om one or more seismic sources through the multi-layered system; receiving signals emanatin g from the multi-layered system in response to the one or more seismic waves with one o r more receivers located a distance from the one or more seismic sources; identifying one or more critically refracted compressional (CRC) waves amongst the signals; and inferring information abo ut a change in the slow layer based on the one or more CRC waves; wherein the CRC wave is a refracted wave which has traveled along an interface between the fast layer and an adjacent layer.