【摘要】 在中国地震台网的宽频数字地震计和倾斜、重力仪的观测中,记录到来自西太平洋热带气旋(热带风暴、台风)引起的震颤波.通过对2006年来自西太平洋的全部热带气旋的分析,以及所观测到的震颤波与气旋运动过程中强度的变化、运动路径、观测点与其之间的距离变化等方面的分析研究得到以下结论:震颤信号的持续时间与热带气旋的生命过程基本相符,其中出现强震颤的时间大多为2～3天,特征为信号的包络线呈纺锤状叠加在观测背景上,震颤波的主要频率范围为0.13～0.33 Hz(周期:3～7 s).我国内陆大部分区域内的宽频地震计、重力仪、倾斜仪等都能清晰记录到这类由热带气旋引起的震颤波.震颤波的强度主要与热带气旋的强度、运动路径以及气旋中心到地震观测台站的距离这几个因素直接相关;而震颤波的变化过程与热带气旋的运动和变化过程密切相关,其中强震颤波的出现时间与气旋过大陆板块边界进入大陆架的时间一致.经对热带气旋的结构、运动规律及动力学特点的了解分析,初步分析认为其主要源于热带气旋运动过程中与浅海区大陆架及陆地表面的摩擦、气压载荷变化以及由此产生的海浪对地壳板块的冲击,及板块边界断层对气旋扰动的响应.此外,我们对北印度洋孟加拉湾生成并在缅甸登陆的热带气旋也进行了实例分析.结果表明:与西太平洋相比,北印度洋热带气旋引起的震颤波对我国大陆的地震观测而言信号较弱.更多还原

【Abstract】 This paper reports the tremor triggered by the tropic cyclone.The character of tremor signal is that the envelope like a spindle overlaps with the observational background curve, with a duration of 2 to 3 days, and the tremor frequency domain in the range of 0.13 to 0.33 Hz (period 3 s to 7 s).Most of the broadband seismometer, tiltmeter and gravimeter in China mainland can record the tremor.We study the cross-correlation between the cyclone and tremor.The result shows that the intensity, moving path of the cyclone and the distances between the cyclone and stations have strong cross-correlation with tremor.Based on this result, we conclude that this tremor is caused by the friction and the interaction between cyclone and the continental shelf, the surface of the earth and ocean, and the fault of plate responding to cyclone.Besides we study the cyclone generated in Bay of Bengal in North Indian Ocean and landed in Myanmar.The result shows that comparing to the cyclone in Western Pacific ocean, the cyclone generated in North Indian Ocean has little effect on tremor observed in China mainland.更多还原