Geologists are the experts who discover oil in different places. Geologists use a variety of techniques to find oil. They also study the surrounding area for signs that there may be trapped oil. The presence of oil can be directly determined by locating the source rock and reservoir rock. Satellite images can also be used to locate oil-rich areas.
Many techniques are used, including sensitive gravity meters. These sensors can detect very small changes in the earth's gravitational field, which could indicate that there is oil flowing. When shock waves pass through rock layers, they are used to study the reflected waves for oil. Once geologists have made a discovery, drilling is used to extract the oil.
Preparation is essential for oil drilling companies before drilling for oil can begin. This includes building roads leading to the site of drilling and finding water sources. Pits are built to dispose of rock cuttings from drilling if there are no natural resources nearby.
To prevent environmental damage, pits are covered with plastic. The site may be ecologically sensitive and the extractions must be done away from it. They dig a cellar before drilling the hole.
As the drilling continues, oil is discovered. The well must be prepared for oil extraction. The well is then drained with acid. This clears the channels and allows for oil extraction. Hydrofracking can also be done by pumping in proppants. After oil starts flowing into the well the rig is taken down and equipment for oil extraction is installed.