Abstract: The Shahejie Formation of Paleogene in Qikou Sag of Huanghua Depression is the main target strata of Dagang Oilfield，which is dominated by braided fluvial delta and fan delta sandbodies. The braided fluvial delta is the favorable reservoir. Based on the study of regional tectonic，palaeogeomorphology feature，sedimentary system of the study area，the formation process of the braided fluvial delta is reconstructed and the sedimentary microfacies feature are observed through using the technology of simulation experiment.The experiment shows that the braided fluvial delta from the Kongdian provenance can be divided into 3 subfacies and 7 microfacies.The systematic study on the main controlling factors of the formation and evolution of the braided fluvial delta is completed.It is proved that basement subsidence，relative lake level changes，flow and flow fluctuation，amount of adding sand and mud（sediment supply）and so on are the main controlling factors.By comparing the actual and the experimental thickness of sand body，the distribution of the favorable reservoir in the study area has been predicted. Based on the initial geological pattern and combining with the phenomena and results of the simulation experiment，the sedimentary model of the braided fluvial delta of the second submember of member 3 of Paleogene Shahejie Formation (Es₃²) in Qikou Sag of Huanghua Depression is set up under the experimental condition.

Key words: Huanghua Depression, Qikou Sag, sedimentation simulation, braided fluvial delta, controlling factors, sedimentary model

摘要： 黄骅坳陷歧口凹陷古近系沙河街组是大港油田油气勘探的主要目的层，该组主要发育辫状河三角洲和扇三角洲沉积砂体，其中辫状河三角洲砂体是有利的油气储集体。在区域构造、古地貌和沉积体系等研究基础上，应用沉积模拟技术，再现了研究区孔店物源辫状河三角洲的形成过程和沉积微相特征，在实验条件下，孔店物源辫状河三角洲可划分为3个亚相、7个微相。实验研究表明，基底沉降、相对湖平面升降、流量及流量变幅、加砂量（物源供给）等是影响辫状河三角洲的形成及其演化的控制因素。通过实际砂体和实验砂体厚度展布对比分析，预测了有利储集层分布区域。综合歧口凹陷原始地质模型和实验模拟成果，建立了模拟实验条件下歧口凹陷古近系沙三²亚段辫状河三角洲沉积模式。

关键词: 黄骅坳陷, 歧口凹陷, 沉积模拟, 辫状河三角洲, 控制因素, 沉积模式

CLC Number: 

• P512