The second phase of drilling for natural gas by Deep Sea No 1, the world's first 100,000 metric ton deep-sea, semisubmersible oil production and storage platform has ended.

For over a decade, China has accelerated its exploration of oil and natural gas in the deep sea. From 2012 to 2022, the number of China National Offshore Oil Corporation's deep-water drilling platforms increased from three to 10, of which three are ultra-deep-sea drilling platforms, capable of drilling as deep as 3,000 meters.

This second phase of the drilling in waters off South China's Hainan province has unearthed 12 wells with a total depth of 60,000 meters. Such deep drilling is closer to the Earth's crust to exploit the resources there. Yet deeper drilling leads to greater difficulties; the pressure increases as one drills deeper. According to earlier reports, in the second phase of drilling, the platform encountered pressure as high as 69 million Pascals, or 1,000 times that in a pressure cooker.

Its success means a huge technological breakthrough, coming just three years after the first phase of platform in June 2021. With the second phase of production of natural gas starting soon, the gas field will see its usable reserve rise from 100 billion cubic meters to 150 billion cubic meters and its annual production of natural gas rise from 3 billion to 4.5 billion cubic meters, which will increase the share of natural gas in China's energy mix.