摘要
塔里木盆地顺北地区碳酸盐岩断溶体体系受控于深大走滑断裂,储集空间主要表现为孔洞和裂缝,其极强非均质性加剧了储层地震响应特征的复杂性。该地区断溶体的优质储层埋深不同,不利于传统反演中的低频模型建立。相约束贝叶斯同时反演技术将贝叶斯分类与叠前同时反演相结合,基于纵横波速度与密度等多弹性参数划分不同的相,并针对每一个相进行深度趋势分析,建立相应的弹性参数初始模型,共同约束反演过程,与传统反演技术相比,该技术不仅提高了反演精度,而且还增加了密度反演的稳定性。以顺北地区5号断裂带北段碳酸盐岩断溶体为研究对象,结合生产实际情况,利用弹性参数划分出缝洞灰岩与致密灰岩2种相,进而开展深度趋势分析与反演。通过单个缝洞等效模型试验及实际应用分析,相约束贝叶斯同时反演得到的密度数据与5号断裂带北段W3井和W3C井钻遇储层吻合程度较高,验证了该反演技术在研究区的适用性和结果的可靠性。
Fault-karst carbonate reservoir in Shunbei area of Tarim Basin is controlled by deep strike-slip faults and forms fault-karst system. The reservoir space mainly includes hole and fracture,its strong anisotropism aggravates the complexity of the seismic response characteristics of the reservoir. The high-quality reservoirs in the fault-karst body in this area have different burial depth,which is not conducive to the establishment of lowfrequency models in traditional inversion. The facies based Bayesian simultaneous inversion technology combines Bayesian classification with pre-stack simultaneous inversion,divides different facies based on multi-elastic parameters such as P-wave and S-wave velocity and density,and conducts in-depth trend analysis for each phase to establish initial model.Compared with the traditional inversion technology,this technology not only improves the inversion accuracy,but also increases the stability of the density inversion. Taking the carbonate fault-karst body in the northern section of the No. 5 fault zone in the Shunbei area as the research object,combined with the actual production situation,two facies,fractured-cavity limestone and tight limestone are divided by elastic parameters,and then are conducted with depth trend analysis and inversion. Through the single fracture-cavity equivalent model test and practical application analysis,the density data obtained by the Facies based Bayesian simultaneous inversion is highly consistent with the reservoirs drilled by Wells W3 and W3C in the northern section of the No. 5 fault zone,which verifies the applicability and reliability of the inversion technique in the study area and the reliability of the results.
作者
曹飞
卢志强
CAO Fei;LU Zhiqiang(Research Institute of Exploration and Production,Northwest Branch of SINOPEC,Urumqi 830011,China;Experimental Testing Technology Center,Northwest Branch of SINOPEC,Urumqi 830011,China)
出处
《天然气地球科学》
CAS
CSCD
北大核心
2022年第10期1702-1711,共10页
Natural Gas Geoscience
基金
国家自然科学基金企业创新发展联合基金项目“海相深层油气富集机理与关键工程技术基础研究”(编号:U19B6003)资助.
关键词
5号断裂带北段
断溶体
岩石物理
深度趋势
贝叶斯分类
相约束贝叶斯同时反演
North section of No.5 fault zone
Fault-karst rock mass
Petrophysics
Depth trend
Bayesian classification
Facies based Bayesian simultaneous inversion
