断陷湖盆陡坡带重力流沉积特征及模式——以辽河西部凹陷兴马地区沙三段为例  

Sedimentary characteristics and models of gravity flow in steep slope zone of faulted lacustrine basin——by taking the third member of Shahejie formation in Xingma area of western Liaohe sag as an example

作　　者：李洪楠 LI Hongnan(Exploration&Development Research Institute of Liaohe Oilfield Company,PetroChina,Panjin,Liaoning 124010,China)

机构地区：[1]中国石油辽河油田分公司勘探开发研究院,辽宁盘锦124010

出　　处：《石油地质与工程》2020年第4期12-18,共7页Petroleum Geology and Engineering

基　　金：国家科技重大专项(2016ZX05006-005);中国石油天然气股份有限公司重大科技专项(2017E-16)。

摘　　要：综合利用岩心、薄片、分析化验及测井等资料,对兴马地区沙三段重力流成因类型、沉积特征、主控因素及沉积模式进行研究。结果表明,研究区重力流沉积包括泥石流、碎屑流、高密度浊流及低密度浊流四种类型;存在洪水型和滑塌型两种沉积机制,洪水型沉积形成冲积扇、近岸水下扇,滑塌型沉积形成滑塌浊积扇。近岸水下扇可进一步分为辫状沟道、辫状沟道侧缘及沟道间三种微相;滑塌浊积扇可分为浊积水道及水道侧缘两种微相。根据重力流沉积演化及平面展布特征分析,研究区重力流沉积具有继承性和变化性,以沙三上亚段重力流砂体最为发育。研究区重力流发育受古地貌、物源供给、断层活动强度、多级断层坡折带及兴隆台潜山遮挡作用综合控制,横向形成冲积扇-近岸水下扇-深水滑塌浊积扇沉积演化模式,纵向构成多期重力流扇体相互叠置沉积模式。By comprehensively using the data of core,thin section,laboratory analysis and logging,the genetic type,sedimentary characteristics,the main controlling factors and sedimentary models of gravity flow in the third member of Shahejie formation in Xingma area have been studied.The results show there are four genetic types of gravity flow deposit:debris flow,debris flow,high density turbidity current and low-density turbidity current.There are two depositional mechanisms:flood type and slump type.Flood type deposits form alluvial fans,nearshore underwater fans,and slump type deposits form slump turbidite fans.The nearshore subaqueous fan can be further divided into three microfacies,i.e.braided channel,braided channel side and channel side.The slump turbidite fan can be divided into two microfacies,i.e.turbidite channel and channel side.According to the analysis of the evolution and plane distribution of gravity flow deposits,the gravity flow deposits in the study area have inheritance and variability,and the gravity flow sand body in the upper sub section of the third member of the Shahejie formation is the most developed.The development of gravity flow in the study area is controlled by paleogeomorphology,provenance supply,fault activity intensity,multi-level fault slope break zone and Xinglongtai buried hill blocking.The sedimentary evolution model of alluvial fan nearshore underwater fan deep water slump turbidite fan is formed laterally,and the sedimentary model of multi-stage gravity flow fan is formed longitudinally.

关 键 词：兴马地区 重力流沉积 断陷湖盆 沉积特征 

分 类 号：TE111.3[石油与天然气工程—油气勘探]