摘要
本文在腾冲火山地震宏观研究的基础上,对该地区火山地震的波形、波动方向、波谱等波动特征进行研究,并和世界上一些典型火山地震震例类比分析,认为腾冲火山地震具有如下几点波动特征: 1.腾冲一部份火山地震的P·S波形和构造地震P·S波形相似,震相清晰,震源深度1—10千米,震中位于火山及其附近,可能是A型火山地震。 2.一部份地震震源极浅(0—1千米),震中位于火山口附近和小范围内,P·S波难区分,S波形不明显,P波初动不清,面波较发育,应属于B型火山地震。 3.腾冲火山地震波谱特征显示,其应力降(Δλ)、地震矩(Mo),低于邻区构造地震Δλ、Mo值。 4.腾冲火山地震震源机制结果为上冲击型和拉锥型。
We studied Wave motion features of volcanic earthquakes in the way of wave form, wave
direction, spectrum and so on to be based on macroscopic investigation of Tengchong volcanic shocks.
To compare with some typical volcanic earthquakes at abroad, we consider that Tengchong vol-
canic shocks have following features:
1. wave form of P and S of a part in them is similar to one in respect of tectonic events,
they can belong to A-type one, depth of focus is about 1-10km, epicenter is located in volcano
or neighbor;
2. focus of anothe part of them is very shallow (0-1km), near area; their epicenter is
located at volcanic orifice or P and S ase difficult to be separated, S wave is not obvious,
priliminary phase of P wave is not clear, they belong to B-type events;
3. spectrum features show low sfress drop and seismic moment to compare with one of tec-
tonic shocks in the neigborhood of volcano area;
4. earthquake focal mechanism of uprush type.
出处
《防灾减灾学报》
1990年第1期55-62,共8页
Journal of Disaster Prevention And Reduction
