279 Days How Difficult Is It To Drill A 10,000-meter-deep Well
Mar 05, 2024
On the afternoon of March 4, in the deep Tako 1 well of PetroChina's Tarim Oilfield, located in the hinterland of the Taklimakan Desert in Xinjiang, after 279 days of hard work, the drilling depth finally exceeded 10,000 meters and is currently continuing to advance towards the target depth of 11,100 meters. This is also the first well in my country with a vertical depth of more than 10,000 meters so far. Not only did it once again set the record for the deepest well in Asia, it also set a record in the world today for the shortest time it took to drill a 10,000-meter-deep well.
279 days! Set a record for the shortest time to drill a 10,000-meter-deep well
my country's first Wanmike exploration well was drilled to a depth of 10,000 meters. It not only once again broke the record for the deepest well in Asia, but also set a record in the world today for the shortest time to drill a 10,000-meter-deep well. The drilling process of the Wanmike exploration well is shown on the big screen.
On May 18, 2023, the 10,000-meter drilling rig erected its derrick
May 30, 2023, blast the whistle and start drilling
June 3, 2023 Breaking through 1,000 meters in 4 days
July 27, 2023 5856 meters, more than half of the well depth, drilled into ultra-deep layers
October 25, 2023 8000 meters drilling into difficult formation
December 25, 2023 9000 meters drilled into ultra-deep layer
March 4, 2024 10,000 meters broke through the 10,000-meter mark
The oil and gas burial depth of the Tarim Basin ranks among the top in the world.
It only took 279 days from the whistle blowing to start drilling to the day when the drill exceeded the 10,000-meter mark. After entering a depth of 8,000 meters, drilling time increases, which also means that the difficulty increases.
The Tarim Basin is one of the few large-scale oil and gas basins in the world dominated by high-temperature and high-pressure ultra-deep oil and gas reservoirs. The rocks that generate oil and gas are buried deep underground. Ultra-deep oil and gas resources account for about 19% of the world's total. Currently, traces of oil and gas have been found in most of the 13 sets of formations deposited in the basin, and the cumulative proven oil and gas reserves exceed 5 billion tons of oil equivalent. These oil and gas resources are mainly contained in ultra-deep formations.
To extract these oil and gas resources buried deep underground, drilling 10,000-meter-deep wells is undoubtedly a very challenging super project. It represents the highest level of drilling technology in the world today, and also faces a series of world-class technical problems.
How difficult is it to drill a 10,000-meter-deep well?
Ultra-deep wells in the Tarim Basin are benchmarked against 13 global engineering difficulty indicators. Seven difficulty indicators, including high temperature and pressure, high sulfur content, gravel thickness, salt layer thickness and casing damage, and brine pressure coefficient, rank first in the world. These extreme underground conditions have brought unprecedented challenges to drilling wells 10,000 meters deep.
Wang Chunsheng, Chief Expert of PetroChina Tarim Oilfield Enterprise: Our underground temperature is as high as 210°C, and the chemical additives, downhole tools, sealing materials and electronic components used in drilling are very easy to fail. The second is the high pressure, which is as high as 150 to 200 MPa, far exceeding the seawater pressure at the deepest point of the Mariana Trench, the deepest point on earth. Instruments and instruments are easily damaged by high pressure, and high-density drilling fluids and cement slurries cannot flow smoothly.
In addition to the test of high temperature and high pressure, drilling 10,000-meter-deep wells also needs to deal with complex and changing formation pressures. During the drilling process, safety risks such as well leakage, well kick, and well collapse always threaten the safe progress of the project. In addition, the stratum 10,000 meters underground is as hard as a grindstone, and drilling progress is extremely slow. Currently, only half a meter is drilled an hour on average, and in extreme cases less than 10 centimeters.
Zhang Zhi, deputy manager of PetroChina's Tarim Oilfield Exploration Division: In order to successfully complete the 10,000-meter-deep drilling project, we have condensed the "top ten" technical challenges and the "five major" stuck technologies, organized the scientific and technological forces of industry, academia and research, and carried out interdisciplinary and interprofessional Jointly tackle key problems across units, strengthen theoretical methods of extreme working conditions and research on materials withstanding extreme high temperatures and pressures, accelerate breakthroughs in engineering technology and equipment, and facilitate the exploration and development of oil and gas resources deep within 10,000 meters.
