摘要
2022年1月15日汤加火山剧烈喷发产生了波及全球的大气重力波,距离火山8736~12758 km的中国大陆所有地应变观测站清晰记录到由此产生的短时地表应变变化。应用小波分析方法系统分析了中国近200个地应变观测站记录数据的时空响应与频率特征,主要表现为:由大气重力波激发的短时地表应变变化的持续时间约为1.5 h,其中能量最强的变化集中在前40 min,面应变平均变幅约为186×10^(-10),呈现出单脉冲起伏状变化,形态具有很强的一致性,具备兰姆波传播属性;短时地表应变变化的平均传播速度约为310 m/s,与大气重力波传播速度基本一致。部分观测站还记录到绕地球一圈后再次到达的大气重力波对地表的作用。这是首次通过大范围布设的高精度地应变观测仪记录到大气重力波作用于地表的痕迹,有助于认识地壳运动和大气圈层相互影响的机制。
Objectives:The Tonga volcano erupted violently on January 15th,2022,which produced atmospheric gravity waves affecting around the world,and was clearly recorded by all ground strain observation stations in Chinese mainland with the distance from 8736 km to 12758 km.Methods:The wavelet analysis method is applied to systematically analyze the spatial-temporal response and frequency characteristics of the data recorded by nearly 200 ground strain observations in China.Results:The results show that the duration of change is about 1.5 hours,in which the strongest energy change is occurred at the first 40 minutes.The average amplitude of surface strain is about 186×10^(-10),showing a single pulse as rise and fall change,and the patterns have highly consistency with Lamb wave propagation properties.The average velocity of event propagation is 310 m/s,which is consistent with the propagation velocity of atmospheric gravity waves.Most stations also record the effect of atmospheric gravity wave signals on the surface as they arrive twice around the Earth.Conclusions:It is the first time to record the traces of atmospheric gravity waves acting on the surface through a large scale high-precision ground strain meters and it is helpful to understand the mechanism of interaction between crustal movement and atmospheric sphere.
作者
吕品姬
李正媛
孙伶俐
林俊
唐磊
倪乙鹏
LÜPinji;LI Zhengyuan;SUN Lingli;LIN Jun;TANG Lei;NI Yipeng(Key Laboratory of Earthquake Geodesy,China Earthquake Administration,Wuhan 430071,China;China Earthquake Networks Center,Beijing 100045,China)
出处
《武汉大学学报(信息科学版)》
EI
CAS
CSCD
北大核心
2022年第6期927-933,共7页
Geomatics and Information Science of Wuhan University
基金
国家自然科学基金(42174177,41974018,41974096,41931074)
中国地震局震情跟踪面上项目(2020020204)。
关键词
汤加火山
地应变观测
大气重力波
兰姆波
特征分析
Tonga volcano
ground strain observation
atmospheric gravity waves
Lamb waves
characteristic analysis