Several rock mechanics problems in the development of shale gas in PetroChina
SHI Lin1,2, SHI Can2, TIAN Zhonglan1, ZHANG Kuangsheng3
1 China Petroleum Drilling Engineering Research Institute, Beijing 102206, China 2 College of Petroleum Engineering, China University of Petroleum-Beijing, Beijing 102249, China 3 Oil & Gas Technology Research Institute of Changqing Oilfield Branch Company, CNPC, Xi’an 710018, China
Shale gas is an important unconventional gas resource. PetroChina is using geological evaluation technology in shale gas exploration and development in the Sichuan Basin, and has made remarkable progress. At the same time, there are several rock mechanics problems found in the development of shale gas: (1) The horizontal wellbore direction problem. Due to the complex geological structure of the Sichuan Basin, the current wellbore direction is perpendicular to the direction of the maximum horizon stress and the direction of horizontal boreholes brings a series of engineering problems; (2) The problem of fracturing fluid volume: The imbibition, displacement and energization of fracturing fluid, requiring the maximum increase of fracturing fluid; (3) The reservoir protection problem: In the process of shale gas development, reservoir protection should be correctly understood, and the imbibition of fracturing fluid should be encouraged; (4) The casing deformation problem: Casing deformation is severe, causing serious economic loss. Solving these key problems can further increase shale gas production and
reduce production costs, which are of great significance.
Key words:
shale gas; horizontal stress; fracturing fluid; rock mechanics
SHI Lin, SHI Can, TIAN Zhonglan, ZHANG Kuangsheng. Several rock mechanics problems in the development of shale gas in PetroChina. Petroleum Science Bulletin, 2019, 03: 223-232.