The sides of these structures are composed of unstable rock debris.
There was little dust here, only a few pieces of scattered rock debris.
The middle and lower portions of the glacier are covered with rock debris.
Apart from the ubiquitous rock debris and some superficial damage in places, the structures stood intact.
In the pictures, this section of the glacier is gray with rock debris and has few crevasses.
The track in which the stone rolled was choked with rock debris.
The engineers cleared the rock debris and tested for safety, finishing the project in November of that year.
Despite the noises and the chatter of rattling rock debris, the creature had remained stone still.
Natural forces dispersed and deposited particles of the rock debris.
This rock debris had filled some natural cavities and hallways.