[M-TT49] インフラサウンド及び関連波動が繋ぐ多圏融合地球物理学の新描像

[MTT49-04] 建物内に設置された微気圧計と地震計で同時観測された地震波形についてPart2

*岩國 真紀子¹、新井 伸夫²、乙津 孝之¹、本橋 昌志¹、坂本 豊実¹、藤井 孝成¹、江村 亮平¹、野上 麻美¹、村山 貴彦¹、大井 拓磨³ (1.一般財団法人　日本気象協会、2.名古屋大学減災連携研究センター、3.東邦マーカンタイル株式会社)

キーワード：微気圧計、地震計、地震による微気圧計の機械応答

Surface vertical vibration due to earthquake is considered to excite sound, and it has been observed by barometer or microphone. Recorded pressure change response to seismic ground motion is considered to be due to difference of gravitational pressure observed by barograph moving up and down, air vibration (compressional wave) excited by earthquake ground motion around barograph, and internal mechanical response to acceleration by earthquake.

We started observation with co-located seismometer and barometer in Isumi, Chiba-prefecture (I30JP in The IMS Infrasound Network of CTBTO). This time one of barometer's port is close. A magnitude 4.5 earthquake occurred off south of Chiba-prefecture at a depth 44km. The seismic intensity scale in Isumi was 2. The port open barometer recorded pressure change due to the earthquake. Whereas, the port close barometer did not record pressure change due to the earthquake. It seems that the gravitational pressure change and barometer's internal mechanical response is very little at the seismic intensity 2 earthquake.