扬子区新元古代前震旦纪地层对比  

NEOPROTEROZOIC LITHOSTRATIGRAPHY AND CORRELATION ACROSS THE YANGTZE BLOCK,SOUTH CHINA

作　　者：周传明[1] 

机构地区：[1]中国科学院资源地层学与古地理学重点实验室,南京地质古生物研究所,江苏南京210008

出　　处：《地层学杂志》2016年第2期120-135,共16页Journal of Stratigraphy

基　　金：国家科技部973项目(2013CB835005);中国石油化工股份有限公司海相前瞻性项目"中国新元古代海相地层研究"的资助

摘　　要：近年来，随着离子探针等同位素定年技术的广泛应用，华南扬子区新元古代地层确切的时间框架愈发清晰。来自四堡群、板溪群及相应地层的同位素年龄数据表明，扬子区晋宁四堡造山运动发生的时间约为8．3～8．2亿年前，持续时间可能不到10Myr。板溪群与莲沱组地层不是上下关系，二者基本上是同时异相，莲沱组比板溪群沉积起始时间稍晚。南华系（z2冰系）的底界应放在新元古代比较公认的最早的全球性冰期沉积地层的底部，在华南即长安组或江口组的底部（～720Ma）。受华南新元古代裂谷盆地演化的控制，扬子区从东南盆地相区往西北浅水台地相区，南华系地层厚度变小、发育越来越不完整。南华系最上部南沱组及相应地层的沉积在扬子区分布最为广泛。With the extensive application of radiometric dating techniques including SHRIMP and SIMS, the Precambrian chronostratigraphic framework in the Yangtze block of South China has been changed in recent years. The radiometric ages of Sibao and Banxi groups, and their equivalents indicate that the Jin- ning-Sibao orogeny took place around 830-820 Ma, with a duration of less than 10 million years. The Lian- tuo Formation of the shallow water facies is roughly an equivalent of the Banxi Group in deep water facies, with the deposition of the Liantuo Formation starting later. The base of the Nanhuan System （equivalent to the Cryogenian System） could be placed at the base of the Chang＇an Formation （-720 Ma）, which re- presents the earliest, globally distributed glaciogenie diamictite interval. Controlled by the development of the South China rift basin following the breakup of the supercontinent Rodinia, Neoproterozic successions in the Yangtze block become thicker and more complete southeastward.

关 键 词：岩石地层 晋宁-四堡运动 南华系 新元古界 扬子区 

分 类 号：P534.3[天文地球—古生物学与地层学]