China has achieved a significant breakthrough in deep-Earth exploration with the drilling of a super-deep borehole in the Xinjiang Uygur Autonomous Region which reached the 10,910-meter mark, making it the deepest vertical well in Asia and the second deepest worldwide.
Located in the hinterland of the Taklimakan Desert in the Tarim Basin, "Shenditake 1" is a scientific exploratory borehole with a designed depth of 11,100 meters. In addition to searching for oil and gas resources, it is also tasked with pursuits such as exploring the evolution of Earth.
Since the start of drilling on May 30, 2023, it took only 279 days to reach a depth of 10,000 meters from the surface. However, the drilling process required an additional 300 days to complete another 910 meters after exceeding 10,000 meters.
"Every meter drilled at depths exceeding 10,000 meters poses a challenge. We have overcome difficulties such as ultra-heavy loads, wellbore instability, drill bit fatigue, tool failure, and well leakage within the formation. The drill has continuously penetrated 12 continental strata in the Tarim Basin and finally reached high-quality oil-and gas-bearing rocks in the well section from 10,851 meters to 10,910 meters. This is the first discovery of oil and gas at a depth of over 10,000 meters worldwide, greatly expanding the new field of deep oil and gas exploration beyond 10,000 meters underground," said Wang Chunsheng, chief technical expert of the Tarim oilfield branch of PetroChina, China's largest oil and gas producer.
The onshore well adopts a domestically developed automated drilling rig, which is capable of reaching depths of up to 12,000 meters. Throughout the drilling process, it set five major engineering records, including the world's deepest tailpipe cementing, the deepest wireline imaging logging, the fastest land-based drilling to surpass 10,000 meters, the deepest vertical well in Asia, and the deepest land-based coring operation in Asia.
Based on geological samples and data, researchers have drawn up Asia's first 10,000-meter geological profile, providing invaluable first-hand physical evidence for deep earth science exploration as well as oil and gas exploration.
"The successful drilling of the ultra-deep well over 10,000 meters marks another significant progress in China's deep earth exploration, following the country's achievements in deep space and deep sea explorations. A series of world-class problems and extreme challenges such as ultra-deep depth, ultra-high temperature and ultra-high pressure have been overcome in drilling the 'Shenditake 1' well, and the dual tasks of scientific exploration and oil and gas discovery have been successfully accomplished, thus promoting the iterative upgrade of engineering technology," said He Jiangchuan, vice president of PetroChina.
At present, China's onshore deep and ultra-deep oil and gas resources total 67.1 billion tons of oil equivalent, accounting for 34 percent of the country's total oil and gas resources. And only 3 billion tons of oil equivalent have been proven in China's ultra-deep formations. So far, more than 300 wells drilled in the Tarim Oilfield have reached depths exceeding 8,000 meters, delivering a total production of 19.57 million tonnes of ultra-deep oil and gas.
China's landmark deep-Earth borehole drilling project achieves 10,910-meter milestone
