Updated: 9:25PM CET: The initial version of this article did not specify that the subject was the world's largest metamorphic rock oilfield. This oversight has now been corrected, and we apologize for any confusion.
A crucial discovery for China, aiming to reduce its energy dependence, has come to light with the Chinese oil company China National Offshore Oil Corporation, better known as CNOOC, reportedly uncovering the world's largest metamorphic rock oil deposit in the Bohai Sea. This is reported by Naftemporiki.
The Bozhong 26-6 oil field, discovered in 2022, has now confirmed record levels of hydrocarbon reserves following a series of drilling operations, potentially exceeding 1.3 billion barrels (over 200 million cubic meters).
The gigantic deposit was found in metamorphic rocks in the Bohai Sea, a small inland sea located at the northern tip of the East China Sea and northwest of the Yellow Sea, on the northeastern coast of China.
Spanish geologist Jorge Navarro mentions that the giant deposit was found in an area known as "buried hills".
Oil and gas are typically stored in sedimentary rocks, like sandstones, which normally do not undergo significant alterations or major losses in porosity and permeability due to burial and compression. However, some of these sedimentary rocks, if buried under high temperatures and pressures, undergo a series of physicochemical processes that destroy almost all their porosity and permeability. If these metamorphosed rocks are brought back to the surface by tectonic forces, their petrophysical properties improve. In such a way that, if buried again, they are capable of hosting hydrocarbons.
An example of metamorphosed rocks is shale, from which shale oil is extracted in the USA. Shale oil is produced within the shale when subjected to high temperatures that can be used as fuel known as shale oil.
New Production Record
This discovery is of vital importance for a country like China, which seeks to reduce its energy dependence and maintain a huge current account surplus. China is the world's largest importer of many raw materials, including oil.
China achieved a new record in oil and natural gas production at the end of last year. The national crude oil production averaged 4.16 million barrels per day, according to data from the Chinese government. In this way, the "Asian giant" continues to be the sixth-largest producer of crude oil in the world, approaching Iraq, which is the fifth-largest oil producer in the world, with 4.3 million barrels per day.
China's crude oil production increased to 208 million metric tons in 2023, representing a 1.6% increase compared to the production levels of 2022.
