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腾冲位于青藏高原东南缘印度与欧亚大陆碰撞边界,是中国最年轻的火山区之一.全新世以来的火山主要分布在腾冲盆地的中央,由北向南形成一个串珠状的火山链.为了研究这一地区的壳内岩浆活动以及与火山分布的对应关系,我们在腾冲盆地开展了为期一年的流动地震观测,利用记录的远震波形和接收函数方法反演了台站下方的S波速度结构.结果表明,打鹰山、大-小空山、黑空山存在一个相互联通的岩浆囊,它的深度为6~15 km,南北方向宽约16 km;火山湖具有一个相对独立的岩浆囊,它的深度为9~16 km,南北方向小于8 km,上述两个岩浆囊的深部热流通道位于黑空山与火山湖之间.在测线南端,老龟坡火山下方的低速特征十分突出,岩浆活动集中在10~25 km深度之间,有可能受到大盈江断裂与腾冲火山断裂相互交汇的影响,它与邻近的马鞍山属于另一个岩浆存储系统.火山区的莫霍面深度在38~41 km之间,在大-小空山下方出现局部抬升,部分台站的壳幔边界具有过渡带性质并呈开放状,有可能成为热流物质由地幔进入地壳的上升通道.
Tengchong is located at the collision boundary between India and Eurasia on the southeastern margin of the Tibetan Plateau and is one of the youngest volcanic regions in China.The volcanoes in the Holocene are mainly distributed in the center of the Tengchong Basin and form a beaded volcano chain from north to south.To study In this area, the magmatism in the crust and the correspondence with the volcano distribution have been observed. We conducted a one-year observation of the mobile seismicity in the Tengchong Basin. Using the recorded teleseismic waveform and receiver function method, the S-wave velocity beneath the station was inverted Structure.The results show that there is an intercommunicated magma carapace in Bingyingshan, Da-Xiaokongshan and Heikongshan with a depth of 6-15 km and a width of 16 km in both north and south direction. The volcanic lava has a relatively independent magma pocket, Its depth is 9 ~ 16 km and its north-south direction is less than 8 km. The deep heat flow channels of these two magma pockets are located between Heikong Mountain and volcanic lakes. At the southern end of the line, the low-speed characteristics of the La Kupo volcano are very prominent, The activities are concentrated in the depth of 10-25 km and may be affected by the convergence of the Dayainjiang fault and the Tengchong volcanic fault, which belongs to another magmatic storage system with the adjacent Ma’anshan. Huo face depth between 38 ~ 41 km, large - Small square foot of air a partial lift, the shell mantle boundary portion having a transition band stations were open nature and shape, may become heat mantle material rise into the channel by the crust.