地球学报2017，Vol.38Issue(4)：513-522,10.DOI:10.3975/cagsb.2017.04.08
梵净山群沉积地质特征与原型盆地分析
Sedimentary Features and Basin Prototype of Fanjingshan Group
摘要
Abstract
The Fanjingshan Group, outcropped at the northwest end of the Jiangnan orogenic belt, is a set of low-grade metamorphic volcanic rocks and clastic rocks. The upper part of the Fanjingshan Group could be recognized as turbidite facies and deep marine (bathyal) basin facies. It was divided into Tongchang, Waxi and Duyantang formations. The Tongchang Formation mainly consists of turbidite facies and basin facies, the Waxi Formation is mostly composed of middle fan and outer fan of turbidite facies. The present study of sedimentary facies sequence has revealed that the sedimentary environments from the Huixiangping Formation to Tongchang Formation and to Waxi Formation are of a sedimentary cycle from marine transgression to marine regression. The sediment diffuse of the Tongchang and Waxi formations is in north or northeast direction, suggesting that its source might have been from the south. The particle statistical results show that quartz makes up 23%~34%, consisting mainly of monocrystal quartz. Feldspar makes up 14%~23%, with clasts up to 39%~50%, including sedimentary and volcanic clasts. The source of the Fanjingshan Group was magma arc. In combination with the results obtained and the geochemical analysis of the volcanic tectonic environment of the Huixiangping Formation, it could be concluded that the basin prototype of the clastic rocks of the upper Fanjingshan Group was a initial marginal sea, formed in a back-arc extension.关键词
梵净山群/浊积岩/弧后伸展/岩石大地构造/新元古代Key words
Fanjingshan Group/turbidite/back-arc extension/petrotectonics/Neoproterozoic分类
天文与地球科学引用本文复制引用
范启超,张传恒,游国庆,董琳琳,刘典波,陆晨明..梵净山群沉积地质特征与原型盆地分析[J].地球学报,2017,38(4):513-522,10.基金项目
本文由中国地质调查局项目(编号: 1212011120115)资助. This study was supported by China Geological Survey (No. 1212011120115). （编号: 1212011120115）
