江西广丰广丰群微古植物群的发现及其意义

<正> 江西省广丰一带在中元古代地槽型双桥山群之上和震旦纪地台型志棠组之下发育一套沉积-火山岩过渡型建造,厚达4000余米。赣东北地质大队、江西省地矿局区域地质调查大队及华东地质学院等单位进行过地质调查研究工作,但这套地层从未发现生物化石,故其时代归属和划分各家认识不一。近年来,笔者在这套地层的下部和上部的沉积岩层

Discovery of the micropalaeobotanic flora from the Guangfeng Group in Guangfeng, Jiangxi and its significance

Developed in the Shangrao-Guangfeng area of northeastern Jiangxi is a suite of clastic deposits and volcanic formation of transitional type, which has been named the Guangfeng Group.This group unconformably overlies the Shuangqiushan Group belonging to the Middle Proterozoic deposits of geosynclinal type and disconformably underlies the Zhitong Formation equivalent to the Sinian Liantuo Formation in the eastern Yangtze Gorges belonging to the deposits of platform type.Abundant micropalaeophytes were found for the first time from the sedimentary strata in the lower and upper parts of the Guangfeng Group, which are typical of the Qingbeikou System in a broad sense (c.1000-750 Ma).Discovery of these fossils is very important not only in ascertaining the ages of these strata but also in dividing and correlating them.