赣东北万年地区变质岩地质特征及其地质意义

The geological characteristics and significances of metamorphic rocks of the Wannian in northeast Jiangxi Province

赣东北万年地区出露一套浅变质岩系,根据岩性组合特征、沉积构造及沉积环境分析、岩石地球化学、微古植物化石组合特征及区域对比,认为其与赣北双桥山群存在显著的区别,并对其进行了重新厘定,建立了相应的地层层序。通过综合研究认为本区出露的浅变质岩系之沉积构造环境为大陆岛弧—弧后盆地,其形成时代为中元古代蓟县纪晚期。

The epimetamorphic rocks are exposed in Wannian Northeast Jiangxi region.According to the rock assemblage characteristics,sedimentary tectonic and sedimentary environment analysis ,and rock geochemistry,microfossil flora,they differ from Shuangqianshan group of North Jiangxi.A correspondent stratigraphic sequence was established.By comprehensive research,epimetamorphic rocks exposed in the region occurred in the continental island-back arc basin,which belonged to the later Jixiangi of middle Proterozoic era.