—Property of generating fracture network is the major factor that influences economical and effective exploitation of tight sandstone reservoir. Besides horizontal stress contrast, rock brittleness and natural fracture property are significant factors that affect fracture network extension. By using a new evaluation method of creating fracture network, the complexity of fracture network for tight sandstone cores and shale gas cores were compared after fracturing experiments. This method uses Soundless Cracking Agent (SCA) which could apply continuous expansion force to create fracture network in cores. It also combines with acoustic emission instrument to monitor the fracture propagation pattern. The experimental result shows that one simple planar fracture pattern was likely to be formed in tight sandstone cores, while one complex fracture without dominant fracture was more likely to be created in shale cores. Rock brittleness is not the significant factor that influences fracture network creation for tight sandstone reservoir. This method is a easy and reliable way to evaluate ability of forming fracture network in tight sandstone reservoir after hydraulic fracturing. It also shows the difference of fracture network generation mechanism between shale gas reservoir and tight sandstone reservoir.
—Acoustic emission, brittleness, fracture network evaluation, tight sand reservoir.
Xin Lei, Shicheng Zhang, Bo Xiao are with the College of Petroleum Engineering, China University of Petroleum, Beijing 102249, China (e-mail: email@example.com, firstname.lastname@example.org, email@example.com).
Tiankui Guo is with the College of Petroleum Engineering, China University of Petroleum, Huadong 266580, China (e-mail: firstname.lastname@example.org).
Cite:Xin Lei, Shicheng Zhang, Tiankui Guo, and Bo Xiao, "New Evaluation Method of the Ability of Forming Fracture Network in Tight Sandstone Reservoir," International Journal of Environmental Science and Development vol. 6, no. 9, pp. 688-692, 2015.