摘要
鄂西地区上震旦统陡山论组含磷岩系下伏砾岩的性质和时代归属问题,目前在认识上仍有分岐。笔者通过大量的野外地质调查和研究,在原来有争议的地区发现了冰川擦痕、压坑、磨蚀面、漂砾等冰川遗迹和种种可进行划分对比的标志,认为本区该层砾岩是等时的,均为冰碛砾岩,其时代为下震旦统南地组。
Abstract At present,question has risen in the geological circle of how to constrain the characters and times of the conglomerate layers underlying the phosphate-bearing sequences locating across the western Hubei province. However,a great deal of field investigationby the authors into the districts in question already found not only such glacial marks as glacial strike, loaded hollows, abrasionsl faces and glacial erratic boulders but also various signs usable for stratigraphic correlation. From these findings, conclusion follows that the conglomerate layers are coeval, and hence correlative with Early Sinian Nantuo group,both standing as tillite.