Exploration for oil and gas has evolved from a basic trial-and-error drilling to the application of sophisticated geophysical techniques to predict the best locations for drilling.

Basics of Oil and Gas Traps

Oil and gas are usually associated with sedimentary rocks. The three basic types of sedimentary rocks are shales, sands, and carbonates. The shales are the sources of the hydrocarbons while the sands and carbonates act as the conduits and/or the containers.

Source Rocks

Shales often are deposited with some organic matter, for example, microscopic plant or animal matter, that become part of the rock. When the shales are squeezed under the pressure of overlying rocks and heated by the natural heat flowing from the earth, oil and gas may be formed depending on the type of organic matter involved and the temperature to which the source rock...