中卫及周缘地区位于阿拉善地块、华北板块、北祁连加里东造山带之间,该区上古生代受区域构造和全球海平面变化影响,地层发育与华北地区有较大差异。通过收集整理3条野外实测地质剖面及19条剖面资料,根据剖面岩性、沉积结构、构造、沉积旋回等,对中卫及周缘地区石炭纪岸线变迁、沉积范围、主要海泛期沉积体系及沉积相的纵向演变规律进行了研究。将研究区石炭系地层划分为三角洲、堡岛、碳酸盐岩台地、浅海4类沉积体系。早石炭世早期,南秦岭洋的海水开始入侵研究区南部,沉积范围呈狭长带东西向展布;早石炭世晚期海侵范围逐步向北、向东扩大,于早石炭世形成由阿拉善古陆、鄂尔多斯、北祁连围成的祁连海沉积区。早石炭世海水较深,沉积物以厚层灰岩为主,碳酸盐岩台地和堡岛沉积体系较为发育。晚石炭世海侵继续向北、向东扩大,晚石炭世晚期研究区祁连海与华北陆表海在中央古隆起北部汇合;早二叠世早期,中央古隆起没于水下,祁连海与华北海已广泛连通。晚石炭世至早二叠世早期海平面变化频繁,海水较浅,沉积物以碎屑岩为主并夹有灰岩,主要发育三角洲沉积体系、堡岛沉积体系以及浅海沉积体系。 Zhongwei and its peripheral areas are located between the Alxa Block, the North China Plate and the North Qilian Caledonian orogenic belt. The Paleozoic in this area was affected by the regional structure and the global sea level change. The stratigraphic development is quite different from that in the North China. By collecting and analyzing three field geological survey sections and 19 section data, according to the lithology, sedimentary structure, structure and sedimentary cycle of the section, the changes of the Carboniferous coastline, the depositional range, the sedimentation system during the main flood season, The vertical evolution of sedimentary facies was studied. The Carboniferous strata in the study area are divided into four types of sedimentary systems: delta, bao island, carbonate platform and shallow sea. In the early Early Carboniferous, the seawater from the South Qinling Ocean started to invade to the south of the study area, and the depositional range was east-west distribution of long and narrow belt. In the late Early Carboniferous, the scope of transgression gradually expanded to the north and eastward and formed in the early Carboniferous. Lu, Erdos, Qilian sea surrounded the North Qilian depositional area. In the early Carboniferous, the seawater was deep, the sediments mainly consisted of thick limestone, and the carbonate platform and the Bo island depositional system were well developed. The late Carboniferous transgression continued northward and eastward. In the late Late Carboniferous, the Qilianhai and North China surface seaheads merged in the northern part of the Central Gulong. In the early Permian, the central paleohighs were submerged and the Qilian and North China Seas Connected. The sea level changes frequently from the Late Carboniferous to Early Permian, and the sea water is shallow. The sediments are mainly clastic rocks with limestone sandstone. The sedimentary systems of the deltaic, the baojidan sedimentary system and the shallow sea sedimentary system mainly develop.