VOLCANIC THREAT LEVELS AND CLASSIFICATION OF VOLCANIC ACTIVITY IN CHINA
SEISMOLOGY AND GEOLOGY
2007, 29 ( 3):
Although volcano erupting has not been recorded in Chinese continent during recent years,there are 15 Holocene volcanoes in Chinese continent,and some disturbance signals were reported from some volcanoes in China.Strong hydrothermal activities occurred in Tengchong volcano,some hydrothermal explosions even took place since 1993.Seismic activity in Changbaishan Tianchi volcano has been getting strong remarkably since July of 2002,accompanied with significant surface uplift and geochemical anomalies.Estimation on volcanic threat level is the base of classification of active volcanoes.Based on the results of volcano monitoring and investigation in recent years,the volcanic threat levels and classification of active volcanoes in China continent are discussed in this paper.Based on the volcanic activity levels of the other countries,the volcano threat in China can be rated into 7 levels as safety,attention,stand by,alarm,threat,hazard and disaster,corresponding to the activity stages of dormancy,late-dormancy,disturbance,unrest,being critical,irreversible and violent,respectively.Based on the dangerous levels of volcanoes,the activity of volcanoes in Chinese continent can be classified into 4 kinds:(1)those in the active phase,such as Changbaishan volcano,which is in the process of disturbance;(2)those with some evidences of activity,such as Tengchong volcano,which stays in the late-dormancy stage,but has the potential threat of eruption;(3)those with some possibility of potential eruption,including Wudalianchi,Jingpohu,Haikou volcanoes,where geophysical and geochemical observations all fall in the background category;and(4)those whose volcanism is unclear yet at present,such as Aer Shan,ErKe Shan,XiaoGulihe,Wulanhada,Keluo,Turphan,west Tianshan,Ashi,and Kekexili volcanoes.
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