An Etymological Dictionary of Astronomy and Astrophysics

The uplift of the central parts of the → crater floor due to the impacting force of a large → meteorite.

The shock wave entering the Earth will first move in as a compressional wave (P-wave), but after passage of the compressional wave an expansion wave (rarefaction wave) will move back toward the surface. This will cause the floor of the crater to be uplifted and may also cause the rock around the rim of the crater to bent upward.

See also: → central; → peak.