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利用地球物理资料分析了腾冲火山区的深部构造特征,针对岩浆囊的数量、规模、传输通道以及地幔源区等问题进行了讨论.分析表明,腾冲火山区存在三个尚未完全固结的岩浆活动区域,它们分别位于黑空山、热海以及五合-团田一带.其中黑空山和热海附近的岩浆囊深度在5~25km之间,水平方向达到15~20km,而五合-团田一带岩浆囊的构造特征尚不能确定.上述岩浆囊通过浅部通道与黑空山、小空山以及热海相连,目前还不能判明打鹰山、马鞍山、老龟坡、来凤山等最新一期的火山下方是否存在类似的岩浆囊,也不清楚它们通过怎样的传输通道与已知的壳内岩浆囊相连.一些重要断裂如腾冲断裂、大盈江断裂和龙陵断裂,特别是这些断裂的交汇部位有可能成为连接壳内岩浆囊和上地幔源区的通道.与周边地区相比,腾冲火山区的岩石圈厚度明显减薄,高热活动与印缅块体向东俯冲有密切的联系:岩石圈板片下沉导致地幔上涌和弧后扩张,热流物质穿过壳幔边界进入地壳形成岩浆囊,也不排除中生代以来Sagaing断裂右旋剪切产生的深部效应.尽管腾冲火山区深部动力过程的构造轮廓日渐清晰,仍需开展高分辨地球物理探测才能揭示壳内岩浆系统和传输通道的细节,以便合理建立火山区岩浆活动的构造模型.
Based on the geophysical data, the deep tectonic features of the Tengchong volcanic area are analyzed, and the problems such as the number, size, transmission channel and mantle source area of the magma are discussed.The results show that there are three magma activities in Tengchong volcano area that have not been completely consolidated They are respectively located in Heikongshan, Atami and Wuhe-Tada, of which the depth of magma pockets near Heikongshan and Atami is between 5 ~ 25km and the horizontal reaches 15 ~ 20km, while that of Wuhe - Tuantian The structural characteristics of the magma pockets have not yet been determined. The magma pockets are connected to Heikongshan, Xiaokongshan and Atami through the shallow channel. At present, the latest phase of volcanoes such as Binghaishan, Ma’anshan, Laopucao and Laifengshan can not be identified There are similar magma pockets below, and it is not clear how they are connected to the known magma magma via what kind of transport channels. Some important faults such as the Tengchong, Dayingjiang and Longling faults, especially the intersections of these faults It is possible to become a channel connecting the magma chamber and the upper mantle source.Compared with the surrounding area, the thickness of the lithosphere in Tengchong volcano area is obviously thinned, The subduction of the East is closely related to the subduction of lithospheric plates resulting in upwelling and post-arc dilation of the mantle, and the flow of heat flux through the crust and mantle into the crust to form magma pockets. Nor does it rule out the deep effect of Sagaing fault dextral shear since Mesozoic Although the tectonic profile of deep dynamic process in Tengchong volcano area becomes clear day by day, high - resolution geophysical exploration is still required to reveal the details of magma system and transmission channel in the crust so as to reasonably establish the tectonic model of volcanic magmatism.