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腾冲地区是由元古代的地槽褶皱带,经古生代—三叠纪的地台体制,至侏罗纪开始构造-岩浆活化作用形成的地洼区。该区地洼阶段的演化及成因机制分为二个阶段。早期(侏罗纪-早第三纪)以花岗岩多次侵入为特征。这些花岗岩的主元素、微量元素及同位素特征均可与中国东部地洼花岗岩相对比。此阶段的地台活化作用源自该区的深部活动过程。晚第三世纪开始,该区的大地构造演化机制发生重大转折。巽他陆块与印度陆地的碰撞控制着该区的活化作用,形成广泛的中—基性火山岩喷发,这些火山岩的地球化学研究证明其构造背最及成因均与火山弧岩石相似。因此,从成因机制角度,腾冲地区属一个复合型地洼区。
Tengchong area is composed of Proterozoic geosynclinal fold belt, through the Paleozoic - Triassic platform system, to the Jurassic tectonic - magmatic activation formed depression area. The evolution and genesis mechanism of Diwa stage in this area are divided into two stages. Early (Jurassic - Early Tertiary) characterized by multiple intrusion of granite. The main elements, trace elements and isotopic features of these granites can be compared with the granites in the eastern part of China. Platform activation at this stage is derived from deep activity in the area. The late third century, the area of the tectonic evolution mechanism a major turning point. The collision between the He-Block and the Indian land controls the activation of the area and forms extensive Meso-basic volcanic eruptions. The geochemical studies of these volcanic rocks prove that their tectonic backs are most similar to volcanic arc rocks. Therefore, from the perspective of genetic mechanism, Tengchong area is a composite depression.