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首次在藏东南发现一套早白垩世的陆相火山岩, 称雅则火山岩, 全岩 Rb Sr 等时线年龄1074 Ma。其主体是高钾的安山岩系, 以强亏损高场强元素、富集大离子亲石元素和轻稀土、 La/ Nb 比值 > 2 为特征, 属活动大陆边缘火山岩; 微量元素等指示它产出在安第斯型陆缘环境。其南延即滇西南的腾冲铁窑山大松坡消减型花岗岩带 (100~112 Ma), 反映新特提斯洋在早白垩世有过一次重要的消减过程;晚白垩世的花岗岩具不同的岩石组合和成矿特征,记录了消减后的陆弧碰撞事件。
For the first time in the southeastern Tibet, a series of Early Cretaceous continental volcanic rocks were found, which are called Ya-zhi volcanic rocks. The RbSr isochron age of the whole rock is 1074 Ma. Its main body is high potassium andesite series. It is characterized by high depletion of high field strength elements, enrichment of large ion lithophile elements and light rare earths, and La / Nb ratio> 2, belonging to the active continental margin volcanic rocks. Trace elements such as it indicate its output Andean land boundary environment. The southern extension of the Tengchong-Tiejiaoshan-Datongpo granitic belt (100-112 Ma) in southwestern Yunnan shows that there was an important depletion process in the Early Tethys Ocean during the Early Cretaceous. Late Cretaceous granite Different rock assemblages and metallogenic features recorded the land-arc collision event after reduction.