Transient electromagnetics applied to gas storage monitoring

A multichannel transient electromagnetic survey was carried out in October 1994 over an underground gas storage site in France. It will be followed by a second survey in June 1995 with exactly the same configuration. The idea is to record the differences in the electromagnetic (EM) response between minimum and maximum status of the storage. If successful, the method could reduce the cost of drilling and instrumenting wells to monitor gas movement.