埕岛-桩海地区断陷湖盆不同触发机制深水重力流成因扇体沉积特征及其差异  

Sedimentary characteristics and differences of deep-water gravity flow fans with different triggering mechanisms in continental faulted basin in Chengdao-Zhuanghai area

作　　者：袁静[1] 赵广昊 景安语[2] 宋璠 孙超[2] 高灏 刘晓林[2] 谢君 YUAN Jing;ZHAO Guanghao;JING Anyu;SONG Fan;SUN Chao;GAO Hao;LIU Xiaolin;XIE Jun(School of Geosciences in China University of Petroleum(East China),Qingdao 266580,China;Institute of Exploration and Development,Shengli Oilfield Company,SINOPEC,Dongying 257000,China;CNOOC China Limited,Tianjin Branch,Tianjin 300452,China)

机构地区：[1]中国石油大学(华东)地球科学与技术学院,山东青岛266580 [2]中国石化胜利油田分公司勘探开发研究院,山东东营257000 [3]中海石油(中国)有限公司天津分公司,天津300452

出　　处：《中国石油大学学报(自然科学版)》2025年第1期1-13,共13页Journal of China University of Petroleum(Edition of Natural Science)

基　　金：国家自然科学基金项目(42072134)。

摘　　要：基于岩心精细观察和描述,结合录井、测井和物性分析等资料和古地貌解释成果,以渤海湾盆地埕岛-桩海地区东营组为研究对象,系统研究断陷湖盆中分别由洪水触发的湖底扇和由浅水沉积物滑动滑塌触发的滑塌扇这两种深水重力流沉积扇体的流体演化和沉积特征,并建立其沉积模式,对比两者在发育背景、流体类型、岩相类型和砂体展布型式等方面的差异。结果表明,湖底扇通常经历碎屑流和异重流两个演化阶段,以反-正复合递变层理和块状层理为典型沉积特征,主要发育块状砂岩、CU-FU序砂岩、FU序砂岩相和CU序砂岩相4种岩相类型,可划分为内扇、中扇和外扇3个亚相。滑塌扇经历浅水砂体滑动滑塌、碎屑流和浊流3个阶段,以滑动剪切面、滑塌变形构造、块状层理和粒序层理为主要沉积构造,发育块状砂岩、CU序砂岩和FU序砂岩3种岩相类型,可划分为近端和远端亚相。湖底扇平面上呈规模较大的舌状或朵叶状分布,砂体顺物源方向连续性较好,厚度和砂地比均大于滑塌扇,外扇亚相是其有利砂体发育区;滑塌扇平面上呈透镜状和舌状展布,个体小,数量多,砂体连续性较差,其近端亚相物性好于湖底扇中扇和外扇亚相,为有利砂体的发育相带。Based on detailed core observation and description,combined with geological logging,geophysical logging,physical property analysis,and paleogeomorphological interpretation,this study investigates the fluid evolution and sedimentary characteristics of two types of deep-water gravity flow genetic fans in the continental faulted basin.Using Dongying Formation of the Paleogene in the Chengdao-Zhuanghai area of the Bohai Bay Basin as an example,the study focuses on sublacustrine fans triggered by floods and slump fans caused by the sliding and collapse of shallow water sediments.Sedimentary facies models for both fan types were established,and their differences in development settings,fluid types,lithofacies,and sand body distribution patterns were compared.The results indicate that the sublacustrine fan evolves through two stages:clastic flow and density flow.It exhibits typical sedimentary characteristics such as reverse-to-normal composite grading and massive bedding.Four lithofacies are identified:massive sandstone,CU-FU sequence sandstone,FU sequence sandstone,and CU sequence sandstone.The sublacustrine fan can be subdivided into three subfacies:inner fan,middle fan,and outer fan.In contrast,the slump fan undergoes three stages:shallow water sand bodies sliding and collapse,clastic flow,and turbidity flow.Its main sedimentary structures include sliding shear planes,collapse deformation structures,massive bedding,and grain-sequence bedding.Three lithofacies types are observed:massive sandstone,CU-sequence sandstone,and FU-sequence sandstone,which are categorized into proximal and distal subfacies.On the plane,sublacustrine fans form large-scale tongue-shaped or leaf-like distributions with good continuity along the provenance direction.They exhibit greater thickness and sand-land ratios compared to slump fans,with outer fan subfacies being the most favorable zones for sand body development.Slump fans display lenticular and tongue-shaped distributions with smaller scales and multiple occurrences.The sand bodies in

关 键 词：洪水型重力流 湖底扇 滑塌型重力流 滑塌扇 沉积特征 差异性 有利相带 

分 类 号：TE121.3[石油与天然气工程—油气勘探]