摘要
华南中部中新元古代造山带可以划分为5个地质构造单元:乐平—歙县构造混杂岩亚带、万年海相—滨海相沉积—火山沉积建造、赣东北蛇绿混杂岩亚带、怀玉火山—火山碎屑岩系、东乡—龙游混杂岩亚带。通过对不同构造单元形成大地构造环境分析,认为它们分别形成于火山弧—弧后盆地、弧间盆地、大洋岛弧、洋中脊、火山岛弧、弧前盆地等大地构造环境;华南中部中新元古代造山带属陆—弧—弧—陆碰撞造山带,发育在汇聚型板块边缘地带,古洋盆为一个多岛洋体系。中元古代末期(约1024Ma)古华南多岛洋开始关闭,大约在850Ma左右,整个古华南多岛洋最终关闭。
Middle-New Proterozoic Orogenic Belt in the central part of South China can be divided into 5 geological tectonic units. They are Leping-Shexian tectonic melange belt, Wannian marine-littiral facies sedimentatary-volcanic sedimentary formation, ophiolite mixtite belt in the northeast part of Jiangxi Provice, Huanyu volcanic volcanic-sedimentary rock series, and Dongxiang -Youlong mixtile belt. According to analyzing on the different tectonic units, it is suggusted that they formed in the geotectonic environment of the volcanic arc-back-arc basin, interarc basin, oceanic island, mid-oceanicridge, volcanic island, front-arc basin. Middle-New Proterozoic Orogenic Belt in the central part of South China is likely of the land-arc-arc-land structure. And it developed at the margin of the convergent plates. The ancient oceanic basin formed a structure system called multy-island ocean. In the end of the Middle-Proterozoic( ～ 1 024 Ma), the oceanic basin began to shut, and it closed at ～ 850 Ma.
出处
《地质调查与研究》
2003年第4期200-206,共7页
Geological Survey and Research
基金
国家地质调查项目:1:25万景德镇幅南昌幅上饶幅区域地质调查项目(项目编号:200013000109)
关键词
华南中部
中-新元古代
造山带
多岛洋
大地构造
central part of South China
Mid-New Proterozoic
orogenic belt
geotectonic system
multy-island ocean
