鄂尔多斯盆地天环坳陷克里摩里组岩溶型储层特征新认识

New understanding on karst reservoir characteristics of Kelimoli Formation in Tianhuan Depression, Ordos Basin

王立新 张茹 王菡 易志伟 曲长伟 陈艳艳 赵先然 吴金龙 李伸专

中国石化华北油气分公司，河南 郑州 450006 斯伦贝谢中国公司，北京 100015

North China Oil and Gas Company, SINOPEC, Zhengzhou 450006, China Schlumberger China, Beijing 100015, China

文中综合录井、取心、钻井及测井资料对鄂尔多斯盆地天环坳陷奥陶系克里摩里组岩溶型储层特征进行详细研究，并首次利用三维远场声波成像测井技术刻画岩溶储层在三维空间的展布特征。研究结果表明：研究区克里摩里组岩溶型储层可细分为无充填溶洞相、方解石角砾充填型溶洞相、泥质充填型溶洞相、溶沟相、裂缝相及高阻致密相等6种测井相模式；除高阻致密相外，其他测井相类型均可作为有效储集空间。三维远场声波成像显示：方解石角砾充填型溶洞相延展最远，可达距井12 m的范围；其次为无充填溶洞相，可延展至距井约5 m的范围；泥质充填型溶洞相延展规模较小，仅在井周附近有所发育。研究区岩溶发育程度与岩性相关，且受控于区域构造活动以及后期成岩作用。综合利用测井数据，尤其是三维远场声波成像测井技术，既对克里摩里组岩溶型储层特征进行了精细表征，又描绘了岩溶储层的空间展布，为研究区克里摩里组勘探部署提供了可靠依据。

Mud logging data, coring data, drilling and logging data were used to analyze the characteristics of Karst reservoir of Kelimoli Formation in Tianhuan Depression of Ordos Basin in this study, and the 3D far-field acoustic imaging technology was used to define the distribution characteristics of karst caves in 3D space for the first time. The results show that the karstic reservoir of Kelimoli Formation in the study area could be divided into six logging facies models, including non-filled karst facies, calcite breccia filled karst facies, argillaceous filled karst facies, karst gully facies, fracture facies and high resistivity tight facies. Except high resistivity tight facies, other logging facies types could be identified as effective reservoir space. Based on the results from 3D far-field acoustic imaging technology, the calcite breccia filled karst facies extended up to 12 m away from the wellbore, followed by the non-filled karst facies, which extended to about 5 m away from the wellbore. The extension scale of argillaceous filled karst facies was small, which only developed around the wellbore. The development of karst reservoir was related to lithology, and was controlled by tectonics and diagenesis in later stage. The comprehensive use of logging data, especially 3D far-field acoustic imaging logging technology not only accurately evaluates the characteristics of karstic reservoir in Kelimoli Formation, but also describes the spatial distribution of karst reservoir, which provides a strong basis for the exploration and deployment of Kelimoli Formation.

10.6056/dkyqt202301010