incavation

Noun

 * 1) The act of making hollow.
 * 2) The act of caving in.
 * 3) A hollow; a physical depression; a concavity.
 * 1) The act of caving in.
 * 2) A hollow; a physical depression; a concavity.
 * 1) A hollow; a physical depression; a concavity.
 * 1) A hollow; a physical depression; a concavity.
 * 1) A hollow; a physical depression; a concavity.

Etymology 2
By analogy to excavation.

Noun

 * 1)  An act of earthing artifacts; the burial or entombment of archaeologically interesting items.