Oil is the lifeblood of modern society. With the development of society, the energy crisis has become a major constraint on economic development. According to statistics from 2011, Venezuela in South America currently has the largest oil reserves in the world, with proven reserves reaching nearly 300 billion barrels, accounting for about 20% of the global estimated reserves. It is predicted that the prospective reserves exceed 500 billion barrels. Among the top ten countries with the largest oil reserves, six belong to the Middle East region, with total oil reserves reaching 900 billion barrels, accounting for more than 50% of the global reserves, making it a veritable treasure trove of oil.
Ancient animals (forming oil fields) or plants (forming coal fields) were buried in large quantities. With the increase in temperature and pressure, chemical changes such as decomposition occurred, and after millions of years of enrichment, oil and coal fields were formed. However, for the formation of oil and coal fields, it is crucial to have a stable sedimentary environment and sufficient source rocks. Sedimentary deposits often form on the Earth's surface and are easily damaged by later weathering and erosion. Therefore, in mountainous belts with intense weathering and erosion, such deposits are rarely found. To search for oil and coal, we need to look for relatively stable basins, and the Middle East is an ideal environment for this. China's Daqing, Shengli, and Changqing oil fields are also located in such areas.
The amount of oil reserves depends on three factors: source, migration, and storage. "Source" refers to hydrocarbon-rich organic source rocks. High-quality hydrocarbon source rocks are often associated with the mass extinction of organisms caused by oceanic anoxic events. Since the Cambrian explosion of life, the Earth has experienced multiple oceanic anoxic events, with the last global oceanic anoxic event occurring more than 50 million years ago. "Migration" refers to the decomposition and migration of buried organic matter over a long period of time due to rising temperature and pressure, eventually converging to areas with storage space, which is the key to the enrichment and accumulation of oil and gas. "Storage" refers to the preservation of oil fields. Shallow burial makes them vulnerable to damage, while deep burial makes them difficult to exploit and utilize.
From 600 million years ago to 50 million years ago, when the Tethys Sea closed, the Middle East region had been in a relatively stable tensional environment for more than 500 million years, forming a series of basins. These basins experienced almost all oceanic anoxic events and accumulated a large amount of hydrocarbon source rocks. Coupled with the lack of large-scale mountain-building activities, the oil reservoirs were well preserved. These conditions have created the Middle East's treasure trove of oil.