megathrust
nounEtymology From mega- + thrust.
1
Geography, Geology, Natural sciences A sudden large-scale slip along a fault between a subducting and an overriding plate, resulting in a major earthquake.
- On March 11, 2011, at 2:46 p.m., a magnitude-9 undersea megathrust earthquake struck off the northeastern coast of Japan.2021, Ruth Ozeki, The Book of Form and Emptiness, Canongate Books (2022), page 458: