碳酸盐岩断溶体内部结构识别技术及应用  

Identification technology for internal structures of carbonate fault-karst and its application

作　　者：常少英 曾溅辉[1] 徐旭辉[3] 曹鹏 崔钰瑶 李涛 CHANG Shaoying;ZENG Jianhui;XU Xuhui;CAO Peng;CUI Yuyao;LI Tao(College of Geosciences,China University of Petroleum,Beijing 102200,China;Hangzhou Research Institute of Geology,Pe-troChina,Hangzhou,Zhejiang 310023,China;Geophysical Research Institute,SINOPEC,Nanjing,Jiangsu 211103,China;BGP Intl.,CNPC,Zhuozhou,Hebei 072751,China)

机构地区：[1]中国石油大学(北京)地球科学学院,北京102200 [2]中国石油杭州地质研究院,浙江杭州310023 [3]中国石油化工股份有限公司石油物探技术研究院,江苏南京211103 [4]东方地球物理公司国际勘探事业部,河北涿州072751

出　　处：《石油地球物理勘探》2022年第2期414-422,I0007,共10页Oil Geophysical Prospecting

基　　金：中国石油天然气集团有限公司科学研究与技术开发项目“复杂碳酸盐岩储层结构表征关键地球物理技术研究”(2021DJ3701)和“海相碳酸盐岩有效储层形成与保持机理及分布预测研究”(2021DJ0503)联合资助。

摘　　要：碳酸盐岩断溶体是近年来发现的一种重要的新型碳酸盐岩圈闭类型。断溶体内部结构复杂、识别难度大,一直制约着储量潜力的充分挖掘、油藏的高效开发以及新井投产成功率的提高。常规断裂检测方法如相干、曲率、蚂蚁追踪等以表征断裂分布特征为主,不能很好地刻画断溶体圈闭的外部轮廓及内部结构特征。地震反射特征分析是识别断溶体及其内部结构特征的重要技术手段。基于实际地震资料,首先构建了断溶体“围岩—破碎带—油源主断裂区—破碎带—围岩”地质模型并分析其地震响应特征,利用断溶体顶部地震反射相位一致性特征去除上覆地层反射波形的影响,突出断溶体的弱反射振幅特征;然后利用正交合成张量梯度属性识别断溶体系统外部轮廓;最后利用去除上覆地层波形影响的数据进行波形指示反演,以张量梯度属性作为波形指示反演初始地质模型的约束条件,进而得到既能表征断溶体轮廓特征又能刻画断溶体内部结构特征的反演数据体。研究成果的实际应用为高效井优选、剩余油挖潜、提高油藏采收率以及对断溶体实施措施井建议等提供了重要的技术支持,具有较好的实用推广价值。Carbonate fault-karst is an important new type of carbonate trap discovered in recent years.The difficulty in identifying the internal structures of fault-karst,however,has been restricting the full exploration of reserve potential,the efficient development of oil reservoirs,and the improvement of the success rate of new wells put into production.Conventional methods for fracture detection such as coherence,curvature,and ant tracking mainly characterize the distribution characteristics of fractures,which cannot well describe the external outline and internal structural characteristics of fault-karst traps.In addition,seismic reflection characteristic analysis is an important technical means to identify the internal structural characteristics of fault-karst.Firstly,by the actural seismic data,a fault-karst geological model was built based on the pattern of’adjacent rock/fractured zone/main fractured zone of oil sources/fractured zone/adjacent rock’,and the seismic response characteristics of each zone were analyzed.The consistency in the seismic reflection phase at the top of fault-karst was utilized to remove the reflection waveform influence from overlying formation and highlight the reservoir characteristics of weak reflection amplitude energy of fault-karst.Then,the external outline of the fault-karst system was identified by using the gradient attributes of the orthogonal composite tensor.Finally,the data free from the influence of overlying formation waveforms was employed for waveform indication inversion,and with the tensor gradient attribute as a constraint,the inversion data volume that can characterize the external contour and internal structural characteristics of fault-karst could obtain.The practical application of the research provide important technical support for suggestions including the selection of efficient wells,the exploration of fault-karst with remaining oil potential,enhanced oil recovery,and the implementation of measure wells.Therefore,the research has a great value of applicabilit

关 键 词：断溶体油藏 缝洞结构 张量梯度 波形指示反演 小断距断裂识别 

分 类 号：P631[天文地球—地质矿产勘探]