镇泾地区侏罗纪古地貌与延安组成藏关系

Relation between Jurassic Palaeogeomorphology and Hydrocarbon Accumulation in Zhenjing

为探明镇泾地区延安组油气成藏规律及确定下一步勘探方向,开展了不整合面上覆及下伏地层厚度特征研究。采用地层厚度印模法恢复了红河油田镇泾地区侏罗纪古地貌形态,发现工区存在2条呈60°夹角的古冲沟,且区域内具有上覆地层厚度大而残留地层厚度薄的特征。在此基础上分析了古地貌对延安组成藏的有利条件为:古冲沟及河道砂体是油气运移的良好通道,古地貌斜坡区砂体为油气的有利储集体,受古地形影响的微幅构造和岩性圈闭是油气有利聚集区。研究结果为该地区延安组油气富集潜力区的预测提供了有效指导。

The overlying and underlying strata thicknesses of unconformity are investigated to determine Yanan hydrocarbon accumulation and provide guidance for the further hydrocarbon exploration in Zhenjing. Stratum thickness impression is used to restore the Jurassic palaeogeomorphology of Zhenjing in Honghe Oilfield. There are two paleo-gullies with a intersection angle of 60° in this workarea and this workarea is characterized by large thickness of overlying strata and thin residual strata. In addition,the effects of palaeogeomorphology on hydrocarbon accumulation of Yanan formation are provided. Paleo-gully and channel sandbody provide favorable pathways for hydrocarbon migration,the sandbodies in the Palaeogeomorphology slope area are considered as favorable reservoirs,and the micro-amplitude structures and lithologic traps that controlled by paleotopography are favorable hydrocarbon accumulation areas. This research could provide effective guidance for the further exploration of hydrocarbon accumulation potential area in Yanan formation.