辽河双台子构造带沙三段主要的沉积相类型与成因分析

Main Sediment Types and Genesis of the Third Member of Shahejie Formation (E_2s^3) in the Shuangtaizi Structure Belt,West Sag,Liaohe

沉积相研究是油气勘探、储层质量评价、盆地构造演化的基础和有力手段。本文从双台子构造带沙三段岩芯观察和描述出发,介绍了沉积物的颜色,识别了冲刷面、递变层理、块状层理、准同生变形构造等多种沉积构造,建立了砾岩相、砂岩相和泥岩相等3大类12小类的岩相组合、总结了正递变,反递变、正-反递变和非递变等4种相序。在此基础上,指出双台子构造带沙三段主要的沉积相类型为湖底扇扇中亚相和滑塌碎屑流相。根据岩芯中观察到的各种氧化色泥砾和各种准同生变形构造,结合区域构造演化和古气候特征,认为双台子构造带沙三段重力流沉积的成因是阵发性洪水和地震作用。构造、沉积、气候共同控制了双台子地区沙三段重力流的形成和演化。

The research of sedimentary facies is an important basis and powerful means for petroleum exploration,appraisal of reservoir quality,and tectonic evolution.Starting from the observation and description of the core from the 3rd Member of Shahejie Formation in the Shuangtaizi structural belt,this study examined sediment colors,erosion surface,grade bedding,massive bedding,penecontemporaneous deformation structures,and thus established three types of sedimentary facies consisting of 12 subtype lithological assemblages.Four types of facies sequences,including normal grading,inverse grading,normal-inverse grading and non-grading,were summarized.The research above suggests that the main sedimentary facies of the 3rd Member of Shahejie Formation（E2s3） in Shuangtaizi structure belt was middle sub-lacustrine fan facies and slumping detrital facies.Based on the mud gravels with oxidation colors and peneteconmporaneous deformation structures,and region tectonic evolution and paleoclimate,it can be inferred that the gravity flow of the 3rd Member of Shahejie Formation（E2s3） in the Shuangtaizi region resulted from episodic flooding and earthquake.The formation and evolution of gravity flow in the 3rd Member of Shahejie Formation（E2s3） of the Shuangtaizi region are jointly controlled by tectonic,deposition and climate.