东濮凹陷基准面变化对砂体发育的控制作用分析

Control effect analysis of base level changing on sandbody development in Dongpu Depression

李继东¹ 许书堂¹ 杨玉娥¹ 顾勤¹ 白钧力²

中国石化中原油田分公司勘探开发科学研究院，河南 濮阳 457001 中国石化集团中原石油勘探局地球物理测井公司，河南 濮阳 457001

Research Institute of Exploration and Development, Zhongyuan Oilfield Company, SINOPEC, Puyang 457001, China Geophysical Wireline Logging Company, Zhongyuan Petroleum Exploration Bureau, SINOPEC, Puyang 457001, China

通过基准面变化的研究，分析了其对砂体发育的控制作用，认为东濮凹陷沙三段沉积时期基准面变化频繁，变化频率大于1 000 次/Ma。这种频繁变化导致沙三段中单砂层厚度较小，砂泥岩频繁互层。东濮凹陷古近系基准面变化旋回具典型“旋回含旋回”的特点，沉积物随基准面的变化不断迁移，在四级层序的高位域和低位域形成富集，四级层序界面对储层有比较明显的控制作用，界面附近砂岩比较发育，而且油气也富集，是油气勘探中要寻找的重点目标。

Based on study of base level changing, the control effect of sandbody development is analyzed. It is thought that the base level changes frequently during Es₃ Member deposition with changing rate of more than 1,000 times/Ma, which leads to the thickness thinning of single sand layer in Es₃ Member and frequent alternation of sandstone and mudstone. Paleaogene reservoir in Dongpu Depression has the characteristics of composite base level change cycle. Sediments migrate continuously along with base level changing, which accumulate in the high and the low tracts of the fourth sequence. The fourth sequence interface controls the reservoir obviously. So the sandstones near the interface well develop and the hydrocarbons enrich, which are the targets for oil gas exploration.

10.6056/dkyqt201206006