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40Ar/39Ar年龄数据表明,青藏东缘和印支块体上出露两期新生代具有不同地球化学特征的岩浆活动,它们的时代分别为40～28和16～0Ma.早期高钾岩石沿主走滑断裂如金沙江-红河断裂断续分布,是在转换压缩过程中产生的.晚期高钾岩石广泛分布于裂谷盆地中,它与青藏和东亚地区出现的东-西向伸展有关.结合地球化学示踪结果可知,早期岩浆活动是在陆内俯冲过程中形成的,而晚期岩浆活动则起源于一个新近交代富集的亏损地幔.岩浆间歇期则代表在印度-亚洲东碰撞带一次重要的地球动力学转变,即从由地壳变形控制的过程向由地幔构造占主导的过程转变.
The 40Ar / 39Ar age data show that two Cenozoic magmatic activities with different geochemical characteristics are exposed on the eastern margin of Qinghai-Tibet Plateau and the Indosinian Block, and their ages are 40-28 and 16-0 Ma respectively. Early high-K rock along the main The strike-slip faults such as the Jinshajiang-Honghe fault are discontinuously distributed during the compression and compression process, and late-stage high-K rocks are widely distributed in the rift basins and are related to the east-west extension of the Qinghai-Tibet and East Asian regions. The results of chemical tracing show that the early magmatic activity was formed during the intraconducting subduction, whereas the late magmatic activity originated from a recently depleted mantle enriched in sedimentary rocks. The magmatic intermission represents an important event in the Indian-East Asian collision zone Geodynamic changes, from the process controlled by the crustal deformation to the process dominated by the mantle structure.