Sedimentary facies of Lower Cambrian in Wangjiaping region

Black shales interbeded with limestones fine clastic rocks limestones, and dolomites were deposited in Wangjiaping region during the Early Cambrian Period.This region was a shallow sea depositional area,and there are four lithologic types in middle Yangtze area.According to field section,microscopic analysis and coenocorrelation plaform platform edge and slope-basin developed during the Early Cambrian Period which can be further divided into five facies and ten sub-facies.After the rapid transgression in the beginning of the Early Cambrian Period the depositional enviroment evolved regularly and slowly form basin to continental shelf gentle slope open platform and restricted platform indicating a regressive sequence.Mosaic shelf platform has formed basically after the area developed from submerging platform to gentle slope platform.