鄂尔多斯盆地南部上三叠统重力流沉积的主控因素  

The main controlling factors of gravity flow of the Upper Triassic in the southern Ordos Basin

作　　者：李克永 熊山[3] 牛斌莉 杨堪阳 冯娟萍[1] LI Keyong;XIONG Shan;NIU Binli;YANG Kanyang;FENG Juanping(College of Geology and Environment,Xi′an University of Science and Technology,Xi′an 710054,China;Periodical Center,Xi′an University of Science and Technology,Xi′an 710054,China;Changqing Oilfield Oil Production Prant NO 1,Yan′an 716000,China;PetroChina Yumen Oilfield Company,Jiuquan 735019,China)

机构地区：[1]西安科技大学地质与环境学院,陕西西安710054 [2]西安科技大学期刊中心,陕西西安710054 [3]长庆油田公司第一采油厂,陕西延安716000 [4]中国石油玉门油田公司,甘肃酒泉735019

出　　处：《西北大学学报（自然科学版）》2018年第4期603-610,共8页Journal of Northwest University（Natural Science Edition）

基　　金：国家科技重大专项专题基金资助项目(2017ZX05005002-004);国家自然科学基金资助项目(41502107);陕西省自然科学基础研究计划基金资助项目(2013JQ5009);地质矿产调查评价基金资助项目(121201011000150014)

摘　　要：结合前人研究成果,对鄂尔多斯盆地南部上三叠统重力流沉积特征进行分析,并运用地震沉积学、沉积构造学等理论,结合测井、岩心观察、野外露头等资料,对鄂尔多斯盆地南部不同类型重力流特征、沉积模式和主控因素进行研究。研究表明,盆地南部地区晚三叠世发育滑塌沉积、砂质碎屑流沉积、泥质碎屑流沉积和浊流沉积等4种重力流沉积类型;其中,滑塌砂体发育揉皱变形及微褶皱、火焰状构造、球枕构造,泥岩中有砂岩注入体,砂质碎屑流、浊流砂岩底部见平行层理和小型砂纹层理,浊积岩底部常见槽模、沟模等底模构造。受不同水动力条件及盆地底型的影响,不同类型重力流沉积在平面上分布在坡折带及其附近的不同部位。研究认为,沉积物源供应是盆地南部重力流沉积的物质基础,盆地底型为重力流沉积提供空间条件,构造活动是重力流沉积的触发机制。通过鄂尔多斯盆地不同类型重力流沉积模式和主控因素的研究,为盆地其他地区和其他克拉通盆地的重力流沉积研究提供依据。Combined with previous studies, the sedimentary characteristic of the Upper Triassic gravity flow in the southern Ordos Basin were analyzed. The sedimentary characteristics, the main controlling factor and Sedimentary model of different gravity flow have been investigate through the methods of seismic sedimentology, sedimentary tectonic, logging, core observation and field outcrop. The results show that there are four types of gravity flow deposits which are slump deposits, sandy debris flow deposits, muddy debris flow deposits and turbidity deposits. Slump sand bodies develop crumpling and deformation, micro-folds, flaming structures, ball pillow structures, and sandstone intrusions in mudstones.The parallel bedding and small sand stratum bedding are seen sandy debris flow deposits and turbidity sandstone. On the surfaces of turbidite exists some flute casts and groove casts.Affected by different hydrodynamic conditions and basin bottom patterns, different types of gravity flow deposits are distributed on the slope break belt and its vicinity. The study considers that the source supply of sediments is the material basis. The basin bottom type provides space conditions, and structure activity is the trigger mechanism of gravity flow deposition. It provides the basis for gravity flow deposits studies in other regions of the Ordos Basin and other types of cratonic basins by the main control factors and sedimentary patterns.

关 键 词：浊积岩 滑塌构造 盆地底型 重力流 鄂尔多斯盆地 

分 类 号：TE121.1[石油与天然气工程—油气勘探]