—In the hydraulic fracturing process of brittle shale, stress conducting effect of rock matrix is one of the key factors to form a complex fracture network. According to this theory, the experimental study on a novel “Soundless Cracking Agent (SCA) fracturing” was initially carried out. Fracture propogation law on the multistage and simultaneous SCA fracturing of horizontal wells was explored. The fracture morphology was observed for the first time by high-energy CT scanning. The results show that SCA can create fractures by generating huge radial compressing stress and circumferential tensile stress. All weakly consolidated natural fractures and beddings could develop into fracture propagating paths along arbitrary angle. Much flaking debris is also created to prevent fractures from closing and further improves fracture conductivity. For the multistage fracturing, the induced stress caused by the former fractures will reduce the horizontal stress difference, so that for the latter fractures, it is easier to deviate from the preferred fracture plane. The simultaneous fracturing could create high-density fracture zones between two wellbores by fracture interactions between the corresponding segments of the wellbores. The excellent performance of SCA fracturing in laboratory shows great potential and vast development prospects in shale gas reservoir stimulation.
—Fracturing, horizontal wells, shale gas, soundless cracking agent.
Tiankui Guo and Zhanqing Qu are with College of Petroleum Engineering, China University of Petroleum, Huadong 266580, China (e-mail: email@example.com, firstname.lastname@example.org).
Shicheng Zhang and Hongkui Ge are with the College of Petroleum Engineering, China University of Petroleum, Beijing 102249, China (e-mail: email@example.com, firstname.lastname@example.org).
Cite:Tiankui Guo, Shicheng Zhang, Hongkui Ge, and Zhanqing Qu, "A Novel “Soundless Cracking Agent Fracturing” for Shale Gas Reservoir Stimulation," International Journal of Environmental Science and Development vol. 6, no. 9, pp. 681-687, 2015.