The method was also used to remove as rock debris after a vein was attacked using tools and fire-setting to produce the opencast.
22.
"Surface creep " is the slow movement of soil and rock debris by gravity which is usually not perceptible except through extended observation.
23.
The terrain was first gouged by south-moving glaciers, and when they retreated, was marked by mounds of rock debris left in their wake.
24.
One theory proposes that as the glacier melts it leaves behind an accumulation of rock debris in the form of annual recessional moraines.
25.
From then on, the glacier narrows and flows down southwest and accumulates rock debris before turning and ending at an elevation of around.
26.
The higher slopes are so full of rock debris that grazing cattle still is the primary living in Craven, with some sheep marginal.
27.
During the Pleistocene period dating back over two million years ago, glaciation advancing and retreating repeatedly scoured the landscape leaving deposits of rock debris.
28.
About 120, 000 years ago, glaciers of the Saale glaciation deposited thick, unsorted rock debris in the region of the present-day island of Sylt.
29.
The rock is quite unstable and in 1963 a large avalanche originating below it covered the lower section of Emmons Glacier with rock debris.
30.
The sediment generally consists of coarse-grained, water-laid sand and gravel, although gravelly loam may be found where the rock debris is rich in clay.
