Definition of loose ground

i. Broken, fragmented, or loosely cemented bedrock material that tends to slough from sidewalls into a borehole. Also called broken ground.

Compare with: breccia

ii. As used by miners, rock that must be barred down to make an underground workplace safe; also fragmented or weak rock in which underground openings cannot be held open unless artificially supported, as with timber sets and lagging.

Compare with: broken ground

iii. A shattered rock formation, or a formation crisscrossed with numerous, closely spaced, uncemented joints and cracks.

Ref: Long