滇东昆阳群地层序列的厘定及其在中国地层表的位置  

Collate and Stipulate the Sequences of the Mesoproterozoic Kunyang Group in Eastern Yunnan and Its Position in Stratigraphic Column of China

作　　者：高林志[1] 张恒[1] 张传恒[2] 丁孝忠[1] 尹崇玉[1] 武振杰[1] 宋彪[1] 

机构地区：[1]中国地质科学院地质研究所,北京100037 [2]中国地质大学(北京),北京100083

出　　处：《地质论评》2018年第2期283-298,共16页Geological Review

基　　金：本文为科技部基础项目(编号：2015FY310100)、国家自然科学基金资助项目(编号：41372038)和中国地质调查局地调项目(编号：121201102000150009,121201102000161414)的成果.

摘　　要：本文通过滇东地区中元古代昆阳群年代地层学研究,提供了新元古代青白口系柳坝塘组的几组高精度锆石SHRIMP U-Pb年龄,通过新元古代地层柳坝塘组与下伏地层(美党组、大龙口组和富良棚组)连续沉积关系以及昆阳群各组的同位素年代学数据,将滇东地区建立新的"系"一级地层单位,即"玉溪系",填补其在中国地层表中待建系的位置。笔者通过进一步的野外地层追踪和对"原昆阳群"的锆石年龄数据的比对研究,明确了"原昆阳群"争议已久的"倒八序列"为华南古陆西南缘中—新元古代地层的正确沉积序列,并以此在滇东地区建立了完整中—新元古代地层及年代地层层序,结合华北古陆上已建立的西山系(1.4~1.2 Ga),本文将昆阳群分属于西山系(1.2~1.4 Ga)和玉溪系(1.0~1.2 Ga),重新厘定昆阳群时代的归属,以期填补中国地层表中的"待建系"。By the study of the chronostratigraphy of the Mesoproterozoic Kunyang Group, we set a series of SHRIMP U-Pb dating has been achieved from the Liubatang Formation. According to the relationship of the depositional succession between the Neoproterozoic Liubatang Formation and underlying Mesoproterozoic strata, such as the Meidang, Dalongkou and Fuliangpeng formations and their chronostratigrphic data, we first set up new Systemic unit of the Yuxi system in Eastern Yunnan and fill up the position of the undefined （ or unnamed） system in Chinese stratigraphic column. The authors did more field work in Yunnan Province and take the correlation of the isotopic zircon dating in the Kunyang Group. We consider the long term arguer of the ＂eight reverse order＂ is the true sequences of the Meso and Neoproterozoic strata in southwestern margin of the South China Croton. On the basses of the true sequence and combine the Yunxi System （ 1.2 - 1.0 Ga） with the Xishan System （ 1.4 - 1.2 Ga） which had been set up in North China Croton, we consider that the new system fill up the hiatus in the stratigraphic column of China.

关 键 词：滇东地区 玉溪系 锆石SHRIMP U—Pb 昆阳群 

分 类 号：P534.3[天文地球—古生物学与地层学]