东营凹陷东南斜坡泥岩压实规律及超压分布  

Shale Compaction and Overpressure Distribution in Southeast Slope of Dongying Sag,Bohai Bay Basin

作　　者：杨彬[1] 张立宽[2] 张立强 雷裕红[2] 程明[2] 于岚[2] 

机构地区：[1]中国石化胜利油田分公司海洋采油厂,山东东营257237 [2]中国科学院地质与地球物理研究所,北京100029 [3]中国石油大学地球科学与技术学院,山东青岛266555

出　　处：《新疆石油地质》2015年第6期714-718,723,共6页Xinjiang Petroleum Geology

基　　金：国家自然科学基金(41372151);国家油气重大专项(2011ZX05008-004)

摘　　要：对渤海湾盆地东营凹陷东南斜坡99口井的泥岩压实曲线研究发现，泥岩压实具有平面上分带、纵向上分段的特征，平面上泥岩欠压实分布在牛庄洼陷和王家岗斜坡过渡带，而凸起带均为正常压实；纵向上分为下部的欠压实段和上部的正常压实段，欠压实段主要分布在沙二段、沙三段和沙四段（埋深1900—3800m），正常压实段主要分布在沙二段及以上地层中。泥岩流体压力估算和实测砂岩数据表明，东营凹陷东南斜坡地层流体压力分带明显，以沙三段顶为界，分为浅部正常压力段和深部超压段；平面上泥岩超压分布广泛，继承性强，过剩压力高值中心位于牛庄洼陷，超压分布与泥岩欠压实的分布规律基本一致，砂岩的超压范围略小于泥岩。东营凹陷东南斜坡异常压力主要属于沉积型超压，泥岩欠压实作用是超压形成的主要机制。The shale compaction curves from 99 wells in southeast slope of Dongying sag are studied in this paper, indicating that the shale compactions are characterized by transverse zonation and longitudinal segmentation. In transverse section, the shale undercompaction zone is distributed in Niuzhuang sub-sag and Wangjiagang slope transitional belt, in which salient zones are all normal compaction ones, while in longitudinal section, the compaction can be devided into the undercompaction segment in the lower part and the normal compaction seg- ment in the Upper part. The undercompaction segment is mainly distributed in the second, third and fourth members of Shahejie formation with depth of 1 900-3 800 m; the normal compaction segment is in the second member and overlying strata. Also, the calculated shale fluid pressure and the measured sand fluidpressure show that the formation fluid pressure in the southeast slope is of obvious zonation： by taking the top of the third member as boundary line, the normal pressure section occurs in shallow part, while the abnormal overpressure section occurs in deep part. And such a shale overpressure appears in wide lateral distribution with strong inheritance, and the area with excess pressure high value is located in the Niuzhuang sub-sag. The overpressure is basically the same with the shale undercompaction in distribu- tion. The overpressure scale of sandstone is somewhat less than that of shale. The abnormal pressure in southeast slope in Dongying sag belongs to deposit overpressure, and the shale undercompaction is the main mechanism of it.

关 键 词：渤海湾盆地 东营凹陷 东南斜坡 沙河街组 欠压实 泥岩过剩压力 超压 

分 类 号：TE112.221[石油与天然气工程—油气勘探]