An 8,520-meter-deep well in the Shunbei oil and gas field found in China's northwestern Tarim Basin in Xinjiang Uygur autonomous region was completed and entered test stage on Thursday, becoming the deepest onshore well in Asia, Chinanews reported on Friday.

The Shunbei 5-5H borehole has faced multiple difficulties in construction including complicated geologic structure, fracturing ground layers, high temperature of the pit bottom and hard-to-control well trajectory.

The Urumqi-based branch of China Petroleum and Chemical Corp (Sinopec), the constructor of the well, set up a special technical team to solve the problems and conduct tests. After years of efforts, they were able to develop sets of proven technologies on ultra-deep wells, which are usually above 6,000 meters in depth.

The Shunbei oil and gas field was discovered in 2016 in the Tarim Basin. Its crude oil and the gas detected are buried underground as deep as over 8,000 meters. To date, 27 ultra-deep wells have been built on the field.