摘要
根据腾冲火山区67个精密水准测点的4期实测垂直形变资料,和对该火山区已有的地质和地球物理工作的分析,参考了由层析成像推测的腾冲火山岩浆系统动力模型,利用Mogi模型对岩浆房的大小和空间位置进行了最小二乘法反演的初步研究。对4期资料分别进行了形变差的反演计算,所得初步结果表明岩浆活动源比较分散,可能存在3个表示岩浆流入引起地面上升的上升源,和2个表示岩浆流出到断层中引起地面下降的下降源。上升源位置大致沿北东走向的断层分布。而下降源位置则在测区东南一侧,等效岩浆源的深度在6～4km之间,与小震震源的深度大致相符。4年来岩浆活动量约为106m3,量级与国外已喷发的火山相比处于较低活动水平。
Based on the four terms of vertical deformation data measured by 67 precision level measurement stations in the Tenchong volcanic area and the geological and geophysical research result in the area, we used tomography Mogi model and least square inversion method to determine the space location and the radius of the active magma in this area consulting magma dynamic model. We calculated four terms of data respectively, and the primary result shows that the active magma areas are scatter. Some flow into three chambers from depth and cause the surface ascend, while others flow into the porous faults from two chambers and make the surface to descend. There is a main fault in this area, which tends toward northeast. The three positive chambers most distribute along this fault, but the negative chambers are located in the southeast of the fault. The calculated depths of magma chambers are 4-6 km, agree with the depth of the small earthquakes in this area. The amount of active magma within four years is nearly 106 m3. Compared with the foreign erupted volcanoes, it is in a lower activity degree.
出处
《地震研究》
CSCD
北大核心
2005年第3期256-261,共6页
Journal of Seismological Research
基金
国家自然科学基金(40274057)
地震科学联合基金(102099)
云南省"十五"重点项目(15-02-04)联合资助.
关键词
垂直形变
Mogi模型
最小二乘反演
火山活动性
腾冲火山区
vertical deformation, Mogi model, least square inversion method, volcanic activity, Tengchong volcano area
