基于频域分析法的缝洞型油藏岩溶孔道识别方法  

Identification method of karst channels in fracture-cavity reservoirs based on frequency domain analysis

作　　者：孙致学[1] 杨旭刚 王晓光 谭涛[3,4] 冯建伟 SUN Zhixue;YANG Xugang;WANG Xiaoguang;TAN Tao;FENG Jianwei(School of Petroleum Engineering,China University of Petroleum(East China),Qingdao City,Shandong Province,266580,China;School of Energy,Chengdu University of Technology,Chengdu City,Sichuan Province,610059,China;Research Institute of Exploration and Development,Northwest Oilfield Company,SINOPEC,Urumqi,Xinjiang,830011,China;Key Laboratory of Enhanced Oil Recovery for Fracture-Vug Reservoirs,SINOPEC,Urumqi,Xinjiang,830111,China)

机构地区：[1]中国石油大学(华东)石油工程学院,山东青岛266580 [2]成都理工大学能源学院,四川成都610059 [3]中国石化西北油田分公司勘探开发研究院,新疆乌鲁木齐830011 [4]中国石化缝洞型油藏提高采收率重点实验室,新疆乌鲁木齐830111

出　　处：《油气地质与采收率》2021年第1期57-63,136,共8页Petroleum Geology and Recovery Efficiency

基　　金：国家自然科学基金项目“基于离散-连续介质模型的水-EGS传质传热机理及数值模拟研究”(51774317)。

摘　　要：精准识别注采井间岩溶孔道是缝洞型油藏治理水窜通道、扩大注水波及,进而实现该类强非均质性油藏均衡驱替的关键问题。以古暗河岩溶缝洞型油藏为研究对象,提出针对该类油藏岩溶孔道的识别方法。通过对比时域模拟器与频域模拟器的模拟结果,验证了频域模拟器的准确性和高效性,得到了岩溶孔道区域内参数变化所反映的地层特征。研究结果表明,应用谐波压力响应分析的方法识别岩溶孔道具有抗干扰、成本低和准确度高的优点。缝洞型油藏内压力传输主要遵循岩溶孔道,不同位置水头响应的振幅和相位存在不同程度的削减和偏移,通过综合分析各位置的水头响应对于谐波信号的振幅削减度和相位偏移度,即可识别测试点所处区域。结果显示,幅度几乎为0的响应,其测试点位于基质中;相位偏移度较低的幅度响应,其测试点位于岩溶孔道中;相位偏移度较高的幅度响应,其测试点位于靠近岩溶孔道的基质中。Accurately identifying karst channels between injection and production wells is a key issue to the treatment of water channeling in fracture-cavity reservoirs,expansion of waterflood swept volume,and further achievement in balanced displacement of such strongly heterogeneous reservoirs.Taking karst fracture-cavity reservoirs in the palaeo-subterranean river as the research object,we propose a method for identifying karst channels in such reservoirs.Through comparison be⁃tween the results obtained respectively from the time domain simulator and the frequency domain simulator,the accuracy and high efficiency of the latter are verified,and the formation characteristics reflected by the parameter changes in karst channels are obtained.Research shows that harmonic pressure response analysis can identify karst channels with resistance to interference,low cost,and high accuracy.Pressure is transmitted in fracture-cavity reservoirs mainly via karst channels.For head responses at different positions,the amplitude drops and the phase shifts to different degrees.Through comprehen⁃sive analysis of amplitude reduction and phase shift of the head response at each position to the harmonic signal,we can identify the area where the test point is located.The results show that for the response with an amplitude of almost 0,the test point is located in matrices;for the amplitude response with slight phase shift,the test point is located in karst chan⁃nels;for the amplitude response with pronounced phase shift,the test point is located in the matrices close to karst chan⁃nels.

关 键 词：缝洞型油藏 岩溶孔道 频域 谐波响应 振幅削减度 相位偏移度 塔河油田 

分 类 号：TE122[石油与天然气工程—油气勘探]