Increasingly, it is important for the geologist to be able to know what lies beneath the ground, or deep under water, in order to locate accumulations of oil and natural gas. Seismic data allows the geologist and geophysisist to "see" what the rocks look like below the surface. To do this, they use sound waves, and the way this works is quite ingenious. A loud noise is created at the ground (or, in the case of offshore exploration, at the sea surface), and this noise moves through the layers of sediments. Some of these sound waves, having travelled through the earth, bounce back towards the surface (like an "echo", if you were to shout "IS THERE ANY OIL HERE" in a canyon). Instruments collect these echoes, and computers translate them into images similar to what you see above. The data comes back as "time it takes for the echo to return", and it's our job to turn time into depth.
Computers have come a long way in the past 50 years, and we are able to do a better and better job at "seeing" what lies beneath our feet (or boat). This increases our chances of finding oil in deeper and deeper reservoirs.
Can you locate the faults in this photo, where the rocks have slipped past one another? I see at least 15. How might these faults make an effective trap for hydrocarbons? Click here to see how.
Other Tools Used to Find Oil Include....
The Paleontological Research Institution