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利用数字化地震记录资料 ,测定了腾冲火山及其周围地区的地震基本参数 ,结果表明 ,腾冲火山区内的地震活动以微震为主 ,震级多数在 1～ 2 5级之间 ,且地震活动频度低 ;而周围地区的构造地震活动频繁 ,且强度大。在腾冲火山区内地震活动的空间分布也表现出明显的非均匀性 ,以腾冲县城以北 (即 2 5°N以北 )的火山区内地震活动少 ,而县城以南的火山区 (热海热田地区 )微震活动相对多 ,且以微震群的形式发生。根据C F Richter震级标度测定的震级结果 ,火山区的微震活动事件可达 0 4震级单位。震源深度的定位结果给出 ,火山地区的微震震源深度绝大多数在 1～ 6km的范围 ,属于典型的浅源地震 ,而周围地区构造地震的震源深度多多数大于 2 0km。腾冲火山区的微震活动分布、地震强度、及震源深度特征所表现的现象可能与地下岩浆体活动相关 ,显示了与火山热物质孕震机理有关的明显特征。
The seismic data of Tengchong volcano and its surroundings were measured by digital seismic record data. The results show that the seismic activity in Tengchong volcano area is mainly microseismic with the magnitude mostly ranging from 1 to 25, and the frequency of seismic activity Low; and the tectonic activity in the surrounding area is frequent and strong. The spatial distribution of seismic activity in Tengchong volcanic area also showed obvious inhomogeneity, with less seismic activity in the volcanic area north of Tengchong county (ie, north of 25 ° N), and volcanic area south of the county Haigetian area) microseismic activity is relatively more, and in the form of microseismic population. According to the magnitude results of the C F Richter magnitude scale, microseismic events in volcanic areas can reach up to 0 4 magnitude units. The focal depth results show that most of the focal depths of microseisms in volcanic regions are in the range of 1 ~ 6km, which are typical shallow earthquakes, while the focal depths of tectonic earthquakes in the surrounding areas are mostly larger than 20km. The phenomena of microseismic activity distribution, seismic intensity and focal depth features in the Tengchong volcanic area may be related to the activity of the underground magmatism and show the obvious characteristics related to the seismogenic mechanism of volcanic thermal material.