Origin, Accumulation and Production of Petroleum and Natural Gas

Oil and gas are made up of prehistoric plant and animal remains. Plant remains have been converted to coal, and animal remains have been converted to oil and gas. These relics sank into the waters, accumulating on the ocean floor and becoming buried behind many kilometers of sediments. There are two types of hydrocarbon reservoirs in the crust: conventional and unconventional. Oil and gas exploration and development in the world has progressed from conventional to unconventional reservoirs.

The study of hydrocarbon accumulation characteristics is crucial element of oil and gas geology research because it can suggest the formation and enrichment of oil and gas. It is also crucial for oil and gas exploration and development. Unconventional oil and gas resources (such as tight gas) are becoming a larger part of global energy consumption, and their accumulation process is more complex than conventional oil and gas.

The process of extracting hydrocarbons and sorting the mixture of liquid hydrocarbons, gas, water, and particles, removing non-saleable ingredients, and selling the liquid hydrocarbons and gas is known as production. Petroleum production entails extracting crude oil and, in many cases, accompanying natural gas from the Earth.