机构地区: 中国科学院地质与地球物理研究所
出 处: 《中国科学院研究生院学报》 2006年第3期349-356,共8页
摘 要: 滇东南建水地区二叠纪火山岩构造侵位于师宗—弥勒断裂带的西南段,以玄武岩、玄武安山岩和安山岩为主,夹有少量苦橄岩.地质、地球化学特征显示其形成于弧后盆地环境,与建水地区石炭纪枕状熔岩相配套.显示扬子陆块和华夏陆块在晚古生代发生了板块俯冲,形成岛弧火山岩,二叠纪时产生弧后引张,形成了弧后盆地.从晚古生代—早中生代,扬子陆块和华夏陆块之间可能存在一个复杂的沟弧盆体系. The Permian volcanic rocks from Jianshui area tectonically intruded into southwest part of Shizong-Mile fault belt. It is mainly comprised of basalts, basaltic andesites, andesites and a little picrites. Geological and geochemical characteristics show that they are formed in back-arc environment, matching Carboniferous pillow lava from Jianshui area. These imply that Yangtze block and Cathaysia block occurred plate-subduction in late Paleozoic forming the island-arc volcanic rocks, and that they produced back-arc extension in Permian, then formed back-arc basins. From late Paleozoic to early Mesozoic, there was a complex trench-arc-basin system between Yangtze and Cathaysia blocks.