CNOOC announced that it had drilled a natural gas well in the ultra deep water area of Liwan 4-1 structure in the the Pearl River Mouth Basin, and tested the daily open flow of natural gas of 430000 cubic meters. This marks the first major breakthrough in the exploration of ultra deep water carbonate rocks in China

The well is located in Baiyun Sag, the largest hydrocarbon rich sag in the Pearl River Mouth Basin, with a water depth of nearly 1640m. The vertical depth of the well is nearly 3000 meters, and the completed drilling depth is nearly 4400 meters. About 650 meters of gas layer was encountered during horizontal drilling. This well reveals the vast exploration prospects in the field of ultra deep water coccidioid limestone in China, and effectively promotes the natural gas exploration process in Baiyun Depression.

In the past, exploration in China's ultra deep water field mainly focused on clastic rocks. The successful drilling of this well for the first time revealed the enormous potential of China's ultra deep water carbonate rock exploration, marking important breakthroughs in exploration understanding and operational technology in this field.

In 2024, CNOOC has achieved five important breakthroughs in exploration.

Kaipingnan Oilfield is located in the the Pearl River Mouth Basin, with proven geological reserves of 102 million tons of oil equivalent, average water depth of about 500 meters, and maximum well depth of 4831 meters. This is the largest oil field independently discovered by China in the deepwater field, and also the largest commercial discovery of nuclear complex type depressions in the world, fully demonstrating the broad prospects of deepwater exploration in China.

The Lingshui 36-1 gas field is located in the western waters of the South China Sea, with an average water depth of about 1500 meters and an average gas layer burial depth of 210 meters. The unobstructed natural gas flow rate of exploration wells exceeds 10 million cubic meters per day, marking a major breakthrough in the exploration of ultra deep and ultra shallow gas layers in China and further consolidating the resource foundation of the trillion square meter atmospheric area in the South China Sea.

The Qinhuangdao 27-3 oilfield has proven geological reserves of 104 million tons of oil, making it the first billion ton level lithological oilfield in the central and northern waters of the Bohai Sea. It is also the sixth billion ton level oil and gas field discovered by the Bohai Oilfield since 2019, the largest crude oil production base in China. The average water depth of the oilfield is about 25 meters. After drilling, the well was found to be 1570 meters deep and encountered an oil reservoir of 48.9 meters. After testing, the daily production of crude oil in a single well of the oilfield is about 110 tons, demonstrating the broad prospects of shallow exploration in the Bohai Sea. Keywords: the Belt and Road news, the Belt and Road project, overseas project.

The Wushi 16-5 structure is located in the Wushi Depression in the Beibu Gulf of the South China Sea, with an average depth of about 25 meters. The evaluation well WS16-5-4 was drilled to a depth of 4185 meters and encountered an oil reservoir thickness exceeding 65 meters. After testing, the average daily oil equivalent of the well exceeds 1000 cubic meters, achieving the breakthrough of the first test thousand cubic meter well in the Wushi Depression, and is expected to become a medium-sized oilfield. At present, the proven geological reserves of crude oil in the Wushi Oilfield Group have exceeded 100 million cubic meters. (This article is from the official website of Jian Dao: www.seetao.com. Reproduction without permission is prohibited, otherwise it will be prosecuted. Please indicate Jian Dao website+original link when reprinting.) Jian Dao website mechanical column editor/Zhou Yingwen