Multidisciplinary monitoring at the Izaute gas storage geophysical laboratory

Izaute is a gas storage facility operated by Total and located in the South West of France. The reservoir, at a depth of 500 m, is filled in the spring and extraction begins in the fall. This cycle is repeated on an annual basis. This site has been selected to be a geophysical laboratory for monitoring techniques due to this periodic behaviour and its easy access. A wealth of geophysical data both seismic (surface and borehole) and non-seismic has been acquired at Izaute on a permanent basis. In this presentation the various geometries used are described. Conclusions are drawn on the on the usefulness of the various techniques in monitoring the movements of the gas - water contact. In particular, the acquired experience has helped promoting downhole optical seismic sensors within more integrated monitoring configurations.