页岩气水平井分布式光纤温度监测高效反演解释方法

An efficient inversion interpretation method for distributed temperature measurement of horizontal wells in shale gas reservoirs

为突破页岩气水平井产出剖面和有效人工裂缝参数快速智能评价技术瓶颈,采用improved dichotomy(ID)算法建立页岩气水平井分布式光纤温度监测(DTS)数据反演模型,实现页岩气水平井产出剖面和每一簇有效人工裂缝参数的高效定量解释,最终形成页岩气水平井分布式光纤温度监测高效反演解释方法。对1口现场页岩气水平井的实测DTS数据进行解释分析,根据DTS数据识别诊断出69条有效人工裂缝。裂缝半长解释结果表明:该井裂缝扩展延伸极为不均,平均有效支撑裂缝半长为61.21 m,部分压裂段内存在明显的优势裂缝,裂缝半长大于120 m;反演模拟的温度剖面与实测DTS数据拟合较好,产出剖面反演解释结果与现场PLT测试产量较为吻合,单压裂段流量最大偏差仅为0.096×10^(4)m^(3)/d,验证了反演解释方法的可靠性。

In order to promote a rapid and intelligent evaluation of production profile and effective artificial fracture parameters for horizontal wells in shale gas reservoirs,an inversion model based on the improved dichotomy(ID)algorithm was developed to interpret the distributed temperature sensing(DTS)data,which can realize an efficient quantitative interpretation of the production profile and effective artificial fracture parameters for horizontal wells in shale gas reservoirs.The measured DTS data of a horizontal well in a shale gas reservoir was analyzed.According to the DTS data,69 effective artificial fractures were identified.The interpreted results of the fracture half-length indicate that the propagation and extension of the hydraulic fractures of the well were extremely uneven.The average supported fracture half-length is 61.21 m,while there are obvious dominant fractures in some fracturing stages of which the fracture half-length is more than 120 m.The inversion simulated temperature profile can be well fitted with the measured DTS data and the interpreted results of the production profile are in good agreement with the PLT test production profile in the field.The maximum deviation of flow rate in any single fracturing stage is only 0.096×10^(4)m^(3)/d that verifies the reliability of the developed inversion model.