松北致密气藏压裂裂缝扩展形态及压裂参数优化

Optimization of fracture morphology and parameters in Songbei tight gas reservoir

松北深层致密气藏沙河子储层属超深致密气藏、纵向呈多小层分布且小层发育薄。为了提高单井产量,针对沙河子组储层水平应力差大,天然裂缝不发育等不利条件,开展基于沙河子储层物理模拟和相关数学模拟的基础研究,建立了沙河子组致密气藏复杂裂缝判断图版并形成对应的体积压裂工艺优选技术,实现了不同区块、不同岩性储层的针对性改造。现场试验14口井,5口井试气产量超过10×10^(4)m^(3),压后工业气流井占比71%,整体提高了松北深层气井的开发效果。研究成果为大庆油田勘探储量的提交以及有效开发提供了有力的技术支撑,同时对国内其它相似油田的开发生产具有借鉴指导意义。

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 10×10^(4)m^(3).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.