鄂尔多斯盆地西缘六盘山地区二三叠统窑山组沉积构造背景初探  

Sedimentary Tectonic Setting of Upper Triassic Yaoshan Formation of Liupanshan Area of Western Ordos Basin

作　　者：冯胜斌[1] 袁效奇[1] 贺静[1] 王成玉[1] 韩鹏[1] 李卫威[1] 李廷艳[1] 

机构地区：[1]中国石油长庆油田分公司勘探开发研究院

出　　处：《低渗透油气田》2009年第3期1-5,共5页

摘　　要：摘要：晚三叠世鄂尔多斯盆地西缘区域构造应力场和六盘山地区窑山组沉积特征、岩矿特征、沉积物碎屑组分特征及其精细沉积时限分析表明．区域应力场特征揭示了中、晚三叠世鄂尔多斯盆地西缘主要受秦祁造山带北东方向挤压和鄂尔多斯地块逆时针旋转应力相互作用，盆地西南缘发生了逆冲推覆构造，六盘山地区整体隆升，其同古陆粱一起构成晚三叠世盆地西界；窑山组西厚东薄和岩矿特征及古水流呈汇聚状特征，显示了其为一独立小湖盆；碎屑组分构造属性指示窑山组沉积环境为挤压坳陷；窑山组形成于晚三叠世晚期（瑞替期）的精细沉积时限，表明了其与延长组非同期沉积．层位高于延长组。综合分析，认为在晚三叠世早、中期，由于冲断带加载和沉积物负荷引起挤压挠曲作用形成了鄂尔多斯盆地西缘类前陆坳陷，盆地西部沉积了巨厚延长组沉积；晚三叠世晚期六盘山地区由于后退式弧形构造带逆冲破裂作用形成背驮式坳陷．形成窑山组沉积，而鄂尔多斯地块及西缘为隆升区，且西缘隆升带为蚀源区。Analysis of sedimentaL＇y features, mineral characteristics of the rock, component characteristics of elastic sediments of Yaoshan Formation in Liupanshan region, and the regional teetonic stress field of the western Ordos basin in Late Triassic and the regional stress field characteristics and detailed analysis of sedimentary time showed that revealed Middle and Late Triassic mainly influenced by the western Ordos Basin. North East to Qin Qi-orogenic extrusion and counterclockwise rotation of the Ordos block the interaction of stress, the basin occmTed in the southwest margin of thrust structure, Liupanshan region uplift as a whole, the same oht Luliang together constitute the Late Triassic Basin, West Side; Yaoshan Formation West, East, thin and thiek rock and mineral characteristics and the ancient water-like features showed aggregation, showing it as an independent small lake; detrital component structural properties directed Yaoshan sedimentary environment for the extrusion depression; Yaoshan Formation tbnned in the late Late Triassic （Rhaetian Age） fine deposition time, shows the Formation of non-extension of the same period with the deposition of layers above the extended Formation. Comprehensive analysis, that the early and middle Late Triassic. due to thrust belt loading and sediment load defleetion caused by squeezing the role of forming the western Ordos Basin foreland depression, west of the basin to extend the Formation deposited thick sediments; Late Triassic Liupanshan regions due to back arc tectonic belt thrust-type role in the formation of rnpture piggyback depression formed Yaoshan Forumtion deposition, while the Ordos block and the western margin of the uplift of the area, and the western edge ~ff uplift bell eroded source area.

关 键 词：:鄂尔多斯盆地西缘 六盘山地区 窑山组 构造环境 

分 类 号：P54[天文地球—构造地质学]