method for producing an underground stratum survey report, apparatus for use in carrying it out, and survey report

摘要

"METHOD FOR PRODUCING A REPORT ON UNDERGROUND STRATEGY, APPARATUS FOR USE IN THE EVENT, AND, REPORT ON REPORT". A system for investigating underground strata. An electromagnetic field and a seismic event are applied from the same location and responses are detected using respective receivers both located at a second spaced location from the first. Responses are combined to identify the presence and / or nature of the underground reservoir. Refracted wave components are used.