hypocenter

/ˈhaɪpəˌsɛntər/
noun
  1. The point inside the Earth where an earthquake rupture begins, directly below the epicenter on the surface.
    • Seismologists calculated that the hypocenter of the quake was about 10 kilometers deep.
    • The earthquake's hypocenter was located near a major fault line under the ocean floor.
    • Knowing the hypocenter helps scientists understand how seismic waves travel through the Earth.
  2. The point on the ground directly below the center of a nuclear explosion, also called ground zero.
    • At the hypocenter of the nuclear test, the heat was intense enough to melt sand into glass.
    • The bomb's hypocenter was marked by a memorial at the site of the blast.
    • Survivors near the hypocenter described a blinding flash followed by a shockwave.
Synonyms