苏皖北部新元古界臼齿碳酸盐岩脉类型及其形成机理

苏皖北部新元古界碳酸盐岩地层中广泛发育臼齿碳酸盐岩脉体.根据这些脉体的产出特征,将其划分为两大类型.类型1主要产出于新元古界下部的刘老碑组、九里桥组和倪园组中,多形成于沉积期,脉体杂乱分布且与叠层石透镜体、砾屑、滑塌构造、冲刷沟槽、透镜状交错层理等共生.类型2主要产出于新元古界中、上部九顶山组、张渠组、魏集组和望山组中...

The Neoproterozoic molar-tooth carbonate rock veins in northern Anhui and Jiangsu Provinces and their forming mechanism

Molar-tooth carbonate rock veins are abundant in the Neoproterozoic carbonate rocks in northern Anhui and Jiangsu Provinces.According to their features in different strata，two types of molar-tooth carbonate rock vein can be identified.Type 1，mostly disorderly outcropped，coexisted with stromatolite bioherms，gravels，debris，slump structures，swash channels and hummocky cross-beddings，were formed in the upper Liulaobei, Jiuliqiao and Niyuan Formaitons which belong to the Lower Neoproterozoic.Type 2，which were stably outcropped in widely spread rhythmic units with graded beds and typical erosion surfaces，were outcropped in other formations which belong to the Upper Neoproterozoic.The initial forming power of the molar-tooth carbonate rock veins might be the crustal movements which were caused by the break-up of the Rodinia.Type 1 was formed in tempestuously changing environments during the depositional period，and might be a prelude signal of the Rodinias break-up，while Type 2 was formed in steadily，periodically changing environments during the early diagenetic process，might indicate that the intermittent release of the earth stress during the break-up period of the Rodinia.