腾冲火山活动区的烈度衰减及环境应力场特征  

INTENSITY DECAY IN TENGCHONG VOLCANIC ACTIVE AREA AND CHARACTERISTICS OF ENVIRONMENTAL STRESS FIELD

作　　者：秦嘉政[1] 皇甫岗[1] 王绍晋[1] 钱晓东[1] 

机构地区：[1]云南省地震局

出　　处：《地震研究》1997年第2期212-217,共6页Journal of Seismological Research

基　　金：云南省科委"腾冲火山活动研究"重大攻关项目经费资助

摘　　要：用云南腾冲火山活动区破坏性地震的烈度分布资料研究了火山活动区的短周期波区域衰减特征，用地震活动资料研究了区域环境应力的空间分布特点。结果给出，腾冲火山活动区的地壳Ｑ值属于低衰减区，平均Ｑ值为８５，比周围地区低５０％左右；环境应力场量值τ０平均为６．０ＭＰａ，属于低应力地区。分析了这种低衰减、低应力背景产生的原因与火山活动区地壳内部高温热物质（如岩浆房）状态的关系，反映了火山活动区地壳内部介质状态与周围构造的差异性，结合其它的有关研究结果，证实腾冲火山活动区地壳内部存在岩浆囊并仍然在活动，由此推测腾冲火山不是死火山。In this paper, using data of intensity distribution of damaging earthquakes in Tengchong volcanic active area, the regional decay characteristic of waves with short periods in the volcanic active area has been studied. The spatial distribution features of the regional environmental stress field has also studied using data of seismic activity. The results show that the crustal Q values in Tengchong volcanic area beolng to low decay area, averaging 85, which are about 50% lower than surrounding places; the environment stress field π 0 values belong to low stress area, averaging 6.0 Mpa. The relations between the cause that produces low decay and low stress background and the materiel state located in high temperature (such as magma chamber) inside the crust have reflected the differences between the media state within crust and the surrouding structures. With the results of other studies, it is proved that there exist magma pockets in the crust which still activate, from which it is inferred that the Tengchong volcano is not dead and there exists risk of reeruption in the future.

关 键 词：火山 火山活动区 烈度衰减 环境应力场 地震烈度 

分 类 号：P315.9[天文地球—地震学]