Because these hydrocarbons are lighter than the nearby rocks, they penetrate upward into the nearby rocks until they penetrate into the tightly impermeable rocks above, and the rocks themselves are empty. The oil accumulated in this way forms an oil field.
The reason why Arab countries are so rich in oil resources: Arabia is in the Middle East, which is an ocean with many marine life. Oil consists of the corpses of these marine life and these tropical plants.
Extended data:
There are two theories about the mechanism of petroleum formation: biological deposition and petrochemical formation. The former is widely accepted that oil is formed by the long evolution of organisms in ancient oceans or lakes, which belongs to biological deposition and cannot be regenerated. The latter thinks that oil is generated by carbon in the earth's crust, which has nothing to do with living things and is renewable.
Petroleum is mainly used as fuel oil and gasoline, and it is also the raw material of many chemical industrial products, such as solutions, fertilizers, pesticides and plastics.
There are four main links from searching for oil to using oil, namely, searching, mining, transportation and processing, which are generally called "oil exploration", "oilfield development", "oil and gas gathering and transportation" and "oil refining" respectively. There are many methods of "oil exploration", but whether there is oil underground or not is ultimately confirmed by drilling. The progress of drilling technology in a country often reflects the development of its petroleum industry.
Therefore, some countries compete to announce that they have drilled the first oil well in the world, which shows that they have taken the earliest step in the development of the oil industry. "Oilfield development" means that the distribution range of oil and gas is confirmed by drilling, and the oil well can be put into production to form a certain production scale.
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