贵州毕节地区古生代以来的沉积相特征及沉积矿产的环境制约  

Characteristics of Sedimentary Facies and Environmental Constraints of Sedimentary Minerals Since Paleozoic in Bijie Area,Guizhou Province

作　　者：肖腾 白平 彭家林 陈武 XIAO Teng;BAI Ping;PENG Jialin;CHEN Wu(Regional Geological Survey,Guizhou Bureau of Geology and Mineral Exploration and Development;Guizhou Geological Survey)

机构地区：[1]贵州省地质矿产局区域地质调查研究院 [2]贵州省地质调查院

出　　处：《现代矿业》2022年第11期30-34,共5页Modern Mining

基　　金：贵州省旅游资源大普查项目(编号:黔旅普2016-01)。

摘　　要：毕节地区位于贵州省西北部。区内自古生代以来沉积相类型多样,沉积环境经历了多次海陆之变,沉积矿产丰富。区内的沉积相体系分为碳酸盐沉积和陆源碎屑沉积两大类,前者可进一步划分为开阔台地相沉积、半局限台地相沉积、局限台地相沉积及缓坡型台地相沉积;后者可进一步划分为海相沉积、海陆过渡相沉积及陆相沉积。分析了区内沉积矿产的环境制约因素,结果表明:区内沉积矿产主要为煤、磷、铝、镍钼、页岩气及盐类矿产等,它们的形成受着沉积环境的制约,晚二叠世的沼泽环境控制了煤和页岩气藏的形成,早寒武世初期的缓坡型台地环境制约着磷块岩矿床的形成,早石炭世铝土矿形成于河湖环境,中晚寒武世和早中三叠世盐类矿产的形成受控于炎热干旱气候条件下局限台地上的萨布哈环境,早寒武世早期镍钼矿和页岩气藏的形成与缺氧还原的深水陆棚有关。Bijie area is located in the northwest of Guizhou Province.Since Palaeozoic,the sedimenta⁃ry facies has been diverse,and the sedimentary environment has experienced many changes of sea and land,and the sedimentary mineral resources are rich.The sedimentary facies system formed by various dep⁃ositional processes can be divided into carbonate deposits and terrigenous clastic deposits in the area.The former mainly belongs to marine shallow water carbonate deposits,which can be further divided into open platform facies deposits semi-restricted platform facies deposits,restricted platform facies,and gentle slope platform facies deposits.The latter can be further divided into marine deposits,marine and continental tran⁃sitional deposits and terrigenous deposits.The environmental restriction factors of sedimentary minerals in the area are analyzed.The results show that the sedimentary mineral resources are mainly coal,phospho⁃rus,aluminum,nickel and molybdenum,shale gas,salt minerals and so on in the area,and their forma⁃tion is restricted by the sedimentary environment.The marsh environment controlled the formation of coal and shale gas reservoirs in the Late Permian.The formation of phosphorite deposits was restricted by the gentle slope platform environment in early Early Cambrian.Early Carboniferous bauxite was formed in river and lack environment.The formation of salt minerals in middle and late Cambrian and Early and Middle Tri⁃assic was controlled by the sabha environment on the limited platform under hot and arid climate conditions.The formation of nickel and molybdenum deposits and shale gas reservoirs was related to the deep water shelf of anoxic reduction in the early Early Cambrian.

关 键 词：沉积相 沉积矿产 沉积环境 

分 类 号：P512.2[天文地球—地质学] P611