microseism
/ˈmaɪkroʊˌsaɪzəm/
noun
- A very small, weak earthquake or ground vibration that can only be detected with special instruments.
- Microseisms are often caused by ocean waves hitting the coast.
- The sensitive equipment picked up a microseism that no one on the surface could feel.
- Seismologists recorded a microseism caused by a distant storm at sea.
Synonyms