赣东北晚古生代放射虫化石综述

DISCOVERING FOSSILS ON THE LATE PALEOZOIC RADIOLARIAN IN NORTHEAST JIANGXI PROVINCE

首次在赣东北蛇绿混杂岩带分布的弋阳县及德兴市境内被前人定为中元古界双桥山群与下震旦统志棠组中发现了一批晚古生代放射虫化石。对樟树墩和登山两处与含放射虫硅质岩共生的岩石组合、硅质岩的岩石学、地球化学及放射虫化石属种特点进行了综合分析 ,表明它们应是一套洋盆深水环境的沉积。这一新发现不仅为研究赣东北蛇绿混杂岩带的性质、形成时代 ,也为重新厘定“板溪群”

The radiolarian fossils of Late Paleozoic were discovered by the authors for the first time in 1993 and 1996 from the ophiolitic melange in northeast Jiangxi Province,which has been taken as the Shuangqiaoshan Group of Middle Proterozoic and as the Zhitang Formation of Lower Sinian Series.The fossils and their geological ages are defined by 4 specialists who are Li Hongsheng,Feng Qinglai,Wu Haoruo and Wang Yujing.On the basis of the colligation analysis of the radiolarian bearing siliceous rocks,the rocks association in the Zhangshudun and Dengshan,the petro chemical and geochemical features,and the fossil characteristics,the authors think that the rocks are a set of abyssal basin sediments.Thus,the new discovery provides a scientific basis not only for defining property and age of the ophiolitic melange in northeast Jiangxi Province,but for redefining the tectonic affiliation of the “Banxi Group”and the geotectonic pattern of South China.