渝南大佛岩矿区铝土岩系炭质页岩孢粉组合特征及其意义  

CHARACTERISTICS AND SIGNIFICANCE OF A SPORE-POLLEN ASSEMBLAGE FROM CARBON SHALE IN BAUXITE DEPOSIT OF THE DAFOYAN AREA , SOUTHERN CHONGQING

作　　者：李军敏[1] 尹福光[1] 陈阳[1,2] 贾德龙[1,3] 吕涛[1] 李再会[1] 冯静[1] 

机构地区：[1]成都地质矿产研究所,成都610081 [2]中国地质科学院,北京100037 [3]中国地质大学,北京100088

出　　处：《古生物学报》2012年第4期508-517,共10页Acta Palaeontologica Sinica

基　　金：中国地质调查局渝东地区地质构造演化及铁铝基地研究(1212011085167);西南地区矿产资源潜力评价(1212010813035)成矿地质背景子课题资助

摘　　要：渝南地区红土风化原地残积-搬运再沉积型铝土矿是渝黔地区铝土矿的重要组成部分,因含矿层位横向上变化多端,不同矿区的沉积时代存在比较大的差异。渝南大佛岩矿区代表剖面顶部炭质页岩存在8种指示早石炭世的具环孢子,以及7种具囊和单沟的花粉再沉积组合,但未见指示早二叠世早期的科达类花粉Florinites出现。据此孢粉组合特征,认为大佛岩矿区顶部炭质页岩的部分物源区的沉积时代早于晚石炭世早期,本区铝土岩(矿)的部分物源有可能来自早于晚石炭世早期沉积的底板地层。结合区域地质背景,认为渝南地区铝土矿含矿岩系是一个穿时性地层单位。The bauxite deposits of siallitic weathering crust was formed after geological transportation in sourthern Chongqing which is a part of Qian-Yu area.They are diachronic of sedimentation among different mining areas , because that the orebearing formations are variable.There are 8species spores and 7species pollen in the carbonaceousshale on the top of the bauxite deposits , the spores indicate the age of sedimentation is Early Carbonif-erous.We didn ’ t find Florinites indicating an age of Early Permian.It is thought that some deposits in the shale on the top of bauxite should be ranging from the later Carboniferous to the earliest Permian in age.And the provenance of bauxite might not only be some kind of colloidal deposits , it may also come from the early-Late Carboniferous basal floor.

关 键 词：孢粉组合 炭质页岩 铝土岩系 大佛岩 渝南 

分 类 号：Q914[天文地球—古生物学与地层学]