Exploration seismology / Сейсморазведка

Exploration seismology deals with the use of artificially generated elastic waves to locate mineral deposits (including hydrocarbons, ores, water, geothermal reservoirs, etc.), archaeological sites, and to obtain geological information Гог engineering. Exploration seismology provides data that, when used in conjunction with other geophysical, borehole, and geological data and with concepts of physics and geology, can provide information about the structure and distribution of rock types. Usually, seismic exploration is part of a commercial venture and. hence, economics is an ever-present concern. Seismic methods alone cannot determine many of the features that make for a profitable venture and. even when supplemented by other data, a unique interpretation is rarely evident. Seismic exploration usually stops long before unambiguous answers are obtained and before all has been learned that might possibly be learned, because in someone’s judgment further information is better obtained in some other way, such as by drilling a well. Seismic methods are in continual economic competition with other methods.
Almost all oil companies rely on seismic interpretation for selecting the sites for exploratory oil wells. Despite the indirectness of the method-most seismic work results in the mapping of geological structure rather than finding petroleum directly-the likelihood of a successful venture is improved more thaii enough to pay for the seismic work. The enormous detail produced by 3-D techniques has opened up a huge reservoir engineering potential. Likewise, seismic methods are important in groundwater searches and in civil engineering, especially to measure the depth to bedrock in connection with the construction of large buildings, dams, highways, and harbor surveys, and to determine whether blasting will be required in road cuts, if potential hazards such as limestone caves or forgotten mine workings underlie building sites, if tunnels or mine drifts are likely to encounter water-filled zones, or if faults arc present that might be hazards to a nuclear power plant. On the other hand, seismic techniques have found little application in direct exploration for minerals because they do not produce good definition where interfaces between different rock types are highly irregular. However, they are useful in locating features such as buried channels in which heavy minerals may be accumulated.