The Quest for Black Gold

The search for oil is analogous to a treasure hunt for parties who have a vested interest in the endeavor. Though highly technological methods have been developed to significantly reduce risks, technology has not yet reached the stage of being able to locate an oil reservoir with complete accuracy every time. However, oil companies, investors and geologists can collect key data to assist them in determining locations with the potential to produce oil. Many techniques have been utilized and studied to determine locations with the likelihood of containing oil, a few of which are examined below.

Seismology: Layers of rock below the surface of the earth exhibit varying characteristics that can be evaluated to give geologists a better understanding of the underground environment. Since geologists know what types of formations are the most conducive to the formation of oil reservoirs, they can use information about the density of different rock layers to judge the probability of the presence of a reservoir. During seismic surveys for oil, shock waves are sent through the earth and the data is used to map the rock layers below. Interpretation of this seismic data suggests to scientists whether the subsurface rocks have the characteristics favorable for containing an oil reservoir.

Magnetism: Researchers can measure magnetic fields to obtain clues about the presence of oil deep underground. Slight variations in the earth’s magnetic field can provide clues about the presence of an oil reservoir. Sedimentary rock, which is usually not magnetic, most commonly contains oil deposits, while igneous and metamorphic rock are typically magnetic and do not contain oil deposits. Magnetic surveys can be carried out at the surface of the earth to obtain information about a specific area, or from the air to provide a broadened view of the earth’s magnetic field.

Gravity: Researchers also measure and analyze data about the earth’s gravitational field to locate producing oil reservoirs. Small variations in the earth’s gravitational field can be used to suggest the presence of an oil reservoir below the surface.

Stratigraphy: By studying relationships between fossils, rock characteristics, wells and electrical data, researchers gain useful knowledge about the type and positioning of underground rock layers. Through careful analysis of the subsurface characteristics, researchers can better determine whether the conditions are suitable for oil exploration.

Several methods are used to determine the locations of oil reservoirs before drilling operations begin, and research continues to improve the accuracy of data collected via these methods. Investors, scientists and oil companies are driven to make considerable efforts to improve oil prospecting endeavors due to the inherent risk and the substantial payoff for success. More effective methods of locating oil prior to the commencement of drilling will reduce the cost associated with prospecting and thus facilitate a higher return on oil investments.