Fossil Energy – Exploration
China National Offshore Oil Corporation (CNOOC) has made a significant breakthrough in deep metamorphic buried-hill exploration in the South China Sea, marking China’s first offshore discovery of metamorphic sandstone and slate buried hills
Exploratory well WZ10-5S-2d at the Weizhou 10-5 South oil and gas field in the Beibu Gulf encountered 211 meters of oil- and gas-bearing formations.
CNOOC CEO Zhou Xinhuai stated that this discovery will guide future deep and buried hill exploration and support the company’s strategy to advance theories and technologies for deep offshore resources, strengthen technological self-reliance, and ensure a stable energy supply.
Xu Changgui, CNOOC’s Chief Geologist, noted that the company has recently intensified innovation to tackle complex geological challenges in deep formations and buried hills.
In the Beibu Gulf Basin, CNOOC has made significant discoveries in Paleozoic granite and Proterozoic metamorphic formations, paving the way for large-scale exploration of buried hills and enhancing the potential for secondary development in mature oilfields.
Meanwhile, China’s oil and gas production continues to grow steadily. Data from the National Bureau of Statistics show that in the first half of 2025, industrial crude oil output reached 108 million tonnes, up 1.3 percent year-on-year, while industrial natural gas production hit a record 130.8 billion cubic meters, up 5.8 percent.
Earlier this week, CNOOC also confirmed the discovery of the Huizhou 19-6 oilfield in the eastern South China Sea, with proven reserves exceeding 100 million tonnes.
It is China’s first large-scale integrated clastic oilfield found in deep to ultra-deep layers, marking another milestone in the country’s offshore energy exploration.
