云南景洪泥盆纪地层厘定  

ON THE DEVONIAN STRATA IN JINGHONG,SOUTHERN YUNNAN

作　　者：刘桂春 冯凡斌 俞赛赢 陈光艳[1] 聂小妹[3] 张志斌 冯庆来[3] 

机构地区：[1]云南省地质调查院,云南昆明650041 [2]广东省核工业地质局293队,广东广州510800 [3]中国地质大学地质过程与矿产资源国家重点实验室,湖北武汉430074

出　　处：《地层学杂志》2014年第1期60-64,共5页Journal of Stratigraphy

基　　金：国家自然科学基金项目(No.41172202;41190073);中国地质调查局1/25万<景洪市>等四幅区域地质调查项目;地质过程与矿产资源国家重点实验室项目联合资助

摘　　要：云南景洪东南地区出露一套泥盆纪地层,前人将以粗粒碎屑岩为特征的部分命名为怕当组,根据腕足类化石确定其地质时代为中泥盆世;以碎屑岩、凝灰岩为特征部分命名为南光组,根据植物化石划归上泥盆统。本研究发现,粗粒碎屑岩层序位于剖面上部,南光组位于剖面下部,两者构成完整的浊积扇层序。粗粒碎屑岩层序中发现晚泥盆世标准植物化石斜方薄皮木(Lepotophloeum rhombicum),说明两者地质时代均为晚泥盆世。故建议废除怕当组,两者合并为上泥盆统南光组,属于深海浊流沉积层序。Devonian strata in southeastern Jinghong, Yunnan, were named as the Padang Formation characterized by coarse-grained clastic rocks and the Nanguang Formation characterized by fine-grained volcani- clastie clastic rocks. The Padang Formation was regarded as Middle Devonian according to brachiopods fauna and the Nanguang Formation was assigned to Upper Devonian according to Lepotophloeurn rhorn- bicurn. Our investigation shows that the Irate Devonian index fossil Lepotophloeurn rhornbicum is also pres- ent in the Padang Formation, that the Padang Formation is younger than the Nanguang Formation on the basis of sedimentary sequence, and that the two formations constitute a full sequence of turbidite fan. Therefore, we suggest that the Padang Formation should be abolished, that the entire sequence is named as the Nanguang Formation belonging to the Upper Devonian.

关 键 词：岩石地层 地层层序 地质时代 南光组 怕当组 泥盆系 景洪 云南 

分 类 号：P534.44[天文地球—古生物学与地层学]