孤岛油田南区东部曲流河沉积结构单元分析

Analysis of the depositional texture unit of meandering rivers in eastern part of the south block of Gudao Oilfield

冯伟光

Feng Weiguang

中国石油化工股份有限公司胜利油田分公司地质科学研究院, 山东东营 257015

Geological Scientific Research Institute, SINOPEC Shengli Oilfield Company, Dongying 257015

曲流河储层是我国石油资源的重要载体, 但是目前研究主要还停留在微相级别, 叠置点坝的划分对比研究还稍显薄弱。研究利用"层次分析"方法, 通过分析河道砂体顶面高程差、出现不连续河间砂体、过井地震剖面的波形差异、平面上的砂体厚度差异等四个方面, 有效地在复合河道中划分出单一河道。通过对砂体垂向沉积层序、砂体厚度分布及废弃河道位置的分析可以识别出点坝沉积;利用"砂顶泥岩厚度法"可以快速识别地下废弃河道, 确定点坝沉积的边界;根据Leeder计算河流满岸宽度经验公式及点坝长度与河流满岸宽度的相关公式可以确定点坝沉积的规模。

Meandering river are the main reservoirs of petroleum in China, but at present studies on meandering river still concentrates on microfacies and the studies on classifying and contrast of superimposed point bar is a little bit weaker, unitary river channel could be classified usefully out of composite river channels using analytical hierarchy process and analyzing followed aspects:difference of elevation of apical plane of meandering river, emergence of discontinuous interchannel sandbody, waveform difference of cross well seismic section, and sand body thickness difference in planes. Point bar could be identified by analysis of vertical sequence of sedimentation, distribution of sand rock thickness and position of abandoned channels. Abandoned channels and border of point bar sediments could be identified rapidly with the theory of mud thickness of sand top. Sedimentary scale of point bar could be established by formulas calculating bank full width and full width with point bar length.

中石化十条龙项目"胜利油区主力油田注水开发关键技术研究",项目号:P06078