The Research and Apllication of 3D directional drilling technology for hot dry rock in Gonghe basin, Qinghai Province?China

Abstract

In order to build the first hot dry rock development demonstration project in China, China Geological Survey deployed directional well GH-03 in Gonghe basin, Qinghai Province. However?there are many difficulties during the drilling progress?such as poor reliability of downhole tools and unstable performance of drilling fluid under high temperature, strong abrasiveness and hardness of rock, low bit footage and ROP, great possibility of sticking due to broken formation block falling, high directional difficulty under the condition of reverse formation trend in hard rock, etc. A set of high temperature hard rock efficient directional technology system has been researched and formed?such as the efficient bit, high temperature downhole motor, high temperature resistant MWD, high temperature resistant drilling fluid and cooling technology etc. Through the application of the above technical measures, the first 3D directional well GH-03 in dry hot rock has been successfully reached the target with high precision and the bit footage of GH-03 and the ROP was increased. The Research and Apllication of 3D directional drilling technology for hot dry rock in the well GH-03 can accumulate valuable experience for the construction of similar high temperature hard rock directional wells.