subterranean rumbling

{{Short description|Sound generated by earthquakes}}

{{Earthquakes}}

Subterranean rumbling is a phenomenon in which the ground vibrates and makes sounds due to an earthquake.

During earthquakes or volcanic eruptions, the ground vibrates, sometimes creating short-period seismic wave motion (ground motion) that reaches the air and becomes sounds (sound waves), and low sounds can be heard.Tokuji Utsu『地震学 第3版』P.308 {{ISBN|9784320046375}}

This often occurs during shallow-focus earthquakes and earthquake swarms. Even microearthquakes that produce noticeable tremors can sometimes produce rumbling.

Hard ground tends to amplify rumbling.

In earthquake-prone Japan rumbling is frequently observed near Mt. Tsukuba in Ibaraki Prefecture. This is believed to be due to local exposure of basement rocks.{{Cite web |title=地鳴り |url=https://kotobank.jp/word/地鳴り |access-date=2023-04-13 |website= |publisher=kotobank |language=ja}} During the 1965 Matsushiro earthquake swarm, a remarkable subterranean rumbling was observed.{{Cite web |title=松代群発地震50年特設サイト |url=https://www.data.jma.go.jp/eqev/data/matsushiro/mat50/disaster/higai.html |access-date=2023-04-13 |website=www.data.jma.go.jp}}{{Cite web |title=鳴動 |url=https://kotobank.jp/word/鳴動 |access-date=2023-04-13 |website= |publisher=kotobank |language=ja}}