Optimization of fracture morphology and parameters in Songbei tight gas reservoir

The Songhezi formation in Songbei is in an ultra-deep tight gas reservoir, with multiple thin sublayers distributed vertically. In order to improve single-well production, in view of the unfavorable conditions such as large horizontal stress difference and lack of natural fractures in Shahezi formation, the basic research based on physical simulation and related mathematical simulations for Shahezi formation was carried out. A chart for judging complex fractures in Shahezi formation in the tight gas reservoir and the corresponding technology for choosing fracturing process optimally were established, which could help to realize targeted reservoir reformation under different lithologies and different blocks. 14 wells were tested in the field, among which 5 wells were tested with a gas production exceeding 10×10⁴ m³. Furthermore, the wells producing an industrial gas flow after fracturing accounted for 71%, which improved the overall development effect of deep gas wells in Songbei. The research results provide strong technical support for the submission and effective development of exploration reserves in Daqing Oilfield, and have reference and guiding significance for other similar oilfields in China.