长白山天池火山地震活动与西北太平洋俯冲带内中深源地震关系的研究

STUDY OF THE RELATIONSHIP BETWEEN CHANGBAISHAN TIANCHI VOLCANIC SEISMIC ACTIVITY AND DEEP EARTHQUAKES IN THE NORTHWEST PACIFIC SUBDUCTION ZONE

根据长白山火山活动的地球动力学背景,综合分析西北太平洋俯冲带俯冲作用所引起的中深源地震与长白山火山地震活动及温泉流体化学气体释放变化趋势的关系。认为在北纬35°以北,西北太平洋板块俯冲作用引起的地幔对流的扰动作用下,长白山火山活动从1999年至目前大体经历了3个阶段:1999年6月至2002年5月为扰动起始阶段,2002年6月至2004年为扰动增强阶段,2005年至目前为扰动衰减阶段。在分析了3个阶段内长白山火山地震活动及温泉气体释放特征的基础上,讨论了长白山天池火山目前的活动状态。从日本海至中国东北深源地震区地震活动期和平静期存在的韵律性活动过程出发,对长白山天池火山未来喷发的可能性进行了分析。

On the basis of geodynamics of Changbaishan Tianchi volcanism, we analyzed comprehensively the intermediate and deep focus earthquakes induced by the subduction of the northwest Pacific plate and the relation between the volcanism of Changbaishan and the change tendency of gas released in the thermal spring. We think that volcanic activity of Changbaishan caused by the disturbance of mantle convection with the subduction of Northwest Pacific plate to the northwest of 35°N is divided into three stages from the beginning of 1999 to the present. The first stage with the beginning of the disturbance is from June,1999 to May,2002; The second stage with the intensifying of disturbance is from June,2000 to 2004 ; And third stage with the decaying of disturbance is from 2005 to now. By analyzing the above three stages, we discussed the present activity regime. We analyzed the rhythmic seismicity between the seismically active period and the quietude period of the area from the Japan Sea to the deep-focus earthquake zone of Northeast China and the possibility of eruption of Changbaishan Tianchi volcano in the future.