A method of studying geology, and particularly faults, that lie beneath the surface. It involves digging one or more long holes and carefully studying the sides to see the composition and spatial relationships of the exposed layers of rock and soil. From that information, geologists can infer some of the geological processes at work in an area.

The digging of shallow trenches to expose a coal seam or vein for inspection or sampling.

The action of digging trenches on a side slope to catch any material that might roll across the control lines.

A means of exposing and sampling near-surface geology by digging a trench;