陆相坳陷湖盆深水重力流沉积类型、模式及控制因素分析——以鄂尔多斯盆地延长组长7段为例  

Analysis of sedimentary types,patterns,and controlling factors of deep-water gravity flow in terrestrial depression lake basins:Takeing Chang 7 member of Yanchang Formation of Ordos Basin as an example

作　　者：王岚 王秀娟[3,4] 李文厚 惠萧[3] 刘羽汐 杨文敬 夏晓敏[6] 白斌 WANG Lan;WANG Xiujuan;LI Wenhou;HUI Xiao;LIU Yuxi;YANG Wenjing;XIA Xiaomin;BAI Bin(PetroChina Research Institute of Petroleum Exploration&Development,Beijing 100083,China;National Key Laboratory for Green Mining of Multi-resource of Continental Shale Oil,Daqing 163712,China;PetroChina Changqing Oilfield Company,Xi’an 710018,China;National Engineering Laboratory for Exploration and Development of Low-Permeability Oil and Gas Fields,Xi’an 710018,China;Department of Geology/State Key Laboratory of Continental Dynamics,Northwest University,Xi’an 710069,China;Research Institute of Exploration&Development,Qinghai Oilfield,PetroChina,Dunhuang 736202,China)

机构地区：[1]中国石油勘探开发研究院,北京100083 [2]多资源协同陆相页岩油绿色开采全国重点实验室,大庆163712 [3]中国石油长庆油田分公司,陕西西安710018 [4]低渗透油气田勘探开发国家工程实验室,陕西西安710018 [5]西北大学地质学系/大陆动力学国家重点实验室,陕西西安710069 [6]青海油田勘探开发研究院,甘肃敦煌736202

出　　处：《西北大学学报（自然科学版）》2024年第6期1091-1103,共13页Journal of Northwest University（Natural Science Edition）

基　　金：国家自然科学基金(42072186);中国石油天然气股份有限公司科技课题(2023DJ84)。

摘　　要：鄂尔多斯盆地长7深水沉积是大型坳陷湖盆深水重力流的典型代表。基于多口取心井厘米级岩心描述和测录井、薄片资料,对长7深水重力流沉积的类型、特征、流体性质和沉积演化过程进行探索。明确深水沉积包括4种类型:深湖泥页岩沉积、滑塌沉积、砂质碎屑流沉积、浊流沉积。剖面上三角洲前缘砂体在外力触发条件下发生滑塌,转变为砂质碎屑流,最终演化为浊流。平面上三角洲前缘坡折带末端发育大面积砂质碎屑流舌状体,其前端的浊流沉积呈扇状分布。鄂尔多斯盆地晚三叠世独特的构造背景、气候条件以及强烈的造山活动,造就了鄂尔多斯盆地特有的重力流沉积模式。砂质碎屑流和浊流砂体分别对应长7页岩油的一类、二类砂体,具有近源成藏的优势,油气资源量可观,目前已产生规模效益。The deep-water sedimentary system of Chang 7 in the Ordos Basin is a typical representative of deep-water gravity flow in large depression lake basins.Exploring the types,characteristics,fluid properties,and sedimentary evolution process of deepwater gravity flow sedimentation in Chang 7 based on centimeter level core descriptions,logging,and thin section data from multiple core wells.There are four types of deep-water sedimentation:deep lake mud shale sedimentation,landslide sedimentation,sandy debris flow sedimentation,and turbidity current sedimentation.The delta front sand body on the profile undergoes collapse under external force triggering conditions,transforming into sandpaper debris flow and ultimately evolving into turbidity current.On the plane,a large area of sandy debris flow tongue shaped bodies are developed at the end of the delta front slope break zone,and turbidite deposits are distributed in a fan-shaped pattern.The unique tectonic background and climatic conditions of the Late Triassic in the Ordos Basin,as well as strong orogenic activity,formed a gravity flow sedimentary model unique to this type of large depression lake basin.The sandy debris flow and turbid flow sand bodies are the first and second types of sand bodies of Chang 7 shale oil,respectively,and have currently formed economies of scale.

关 键 词：鄂尔多斯盆地 长7油层组 深水重力流 沉积环境 成因模式 

分 类 号：P618.12[天文地球—矿床学]