压前测试评价在异常高压致密气藏应用研究

压裂测试技术的选择及其分析对压裂设计原则和规模大小的确定至关重要，开展气藏压前测试评价技术可以达到认识储层应力特征、滤失特征和裂缝延展特征的目的，验证裂缝垂向延伸高度与软件模型的一致性。以沙特阿拉伯鲁卜哈里盆地X2S井为例，针对储层物性认识不清的问题开展了注入/压降测试，求取储层有效渗透率；针对交叉偶极声波测井数据解释储层地应力剖面表现出缝高难控制的特征，开展了小型压裂测试及井温测井，计算储层应力剖面和缝长、缝高延展特征；针对侧钻斜井的问题开展了阶梯测试，求取了孔眼摩阻和近井筒摩阻。系统的压前测试评价技术可获取探井致密气藏改造的重要井层资料，对指导主压裂安全施工具有重要作用，为国内异常高温高压致密砂岩气藏压裂提供了借鉴。

APPLICATION AND RESEARCH OF PREFRAC TESTING TECHNOLOGY IN ABNORMAL HIGH PRESSURE TIGHT GAS RESERVOIR

The application of PreFrac technology and analysis of acquired data is important to determine design principle and job size of the fracturing.Through PreFrac evaluation，stress characteristics of the reservoir can be acquired，filtration characteristics and fracture height extension feature can be recognized，and the fracture height and vertical extension also can be verified with software models.In this paper，MFO test，Step Rate test，MiniFrac test and temperature logging technology are implemented in X2S which is located in Rub Al Khali Basin in Saudi Arabia，reservoir parameters are evaluated，the physical property，rock stress property，leak off coefficient and fracture extension character are recognized，fracturing technology is optimized，and the fracturing job is improved and implemented successfully.PreFrac testing is useful for acquiring reservoir parameters and important for safety of oilfield job implementation，also gives good advisements for similar condition well′s stimulation in domestic.