黄骅坳陷中部沙三段沉积体系分析

Sedimentary systems of the third member of Shahejie Formation,central Huanghua Depression

为了揭示黄骅坳陷中部沙三段沉积体系的分布规律,根据对沙三段岩心、测井和地震资料的分析,运用现代沉积学、层序地层学理论,在该段划分出4种沉积体系:扇三角洲体系、辫状河三角洲体系、湖泊体系和重力流体系。根据层序地层学研究结果,沙三段被细分为3个层序(SQ1、SQ2、SQ3)9个体系域。对沙三段各体系域发育期的沉积体系展布特征和物源方向进行了深入探讨,在此基础上预测出5个有利勘探区,即歧南凹陷中部、歧北凹陷东南部、板桥凹陷中部、港东断层下盘和海河断层西南部。

The third member of Shahejie Formation in the central part of Huanghua Depression is one of the most important oil-bearing and exploration formations. Based on modern sedimentology, sequence stratigraphy, core analysis, logging and seismic data, four sedimentary systems are identified in this area, including fan delta system, braided delta system, lake system and gravity flow system. The member is subdivided into three sequences （SQ1, SQ2, SQ3 ） and nine system tracts based on sequence stratigraphy. The distribution patterns of the depositional systems in space and the source provenance in each system tract of the Sha-3 member are analyzed; five favorable areas are predicted, they are the central part of Qinan Sag, the southeastern part of Qibei Sag, the central part of Bancliao Sag, the thrown side of the Gangdong fault and the southwestern part of the Haihe fault.