Geology Reference
In-Depth Information
Plate 10.13
Terminal moraine in front of a cirque glacier, Cordillera Blanca, Peru.
(
Photograph by Neil Glasser
)
Table 10.4 Glaciofluvial landforms
Formative process
Landform
Description
Subglacial
Erosion by
subglacial water
Tunnel valley (
Rinnen
) A large, subglacial meltwater channel eroded into soft sediment or
bedrock
Subglacial gorge Deep channel eroded in bedrock
Nye (bedrock) channel Meltwater channel cut into bedrock under high pressure
Channel in loose sediment Meltwater channel eroded in unconsolidated or other types of glacial
deposit
Glacial meltwater chute Channel running down a steep rock slope marginal to a glacier
Glacial meltwater pothole Circular cavity bored into bedrock by meltwater
Sichelwannen
('sickle-shape troughs')
Crescentic depressions and scallop-like features on bedrock surfaces
caused largely by meltwater, with cavitation being a key process
Deposition in
subglacial
channels, etc
Esker
Lengthy, winding ridge or series of mounds, composed mainly of
stratified or semistratified sand and gravel
Nye channel fill
Debris plugging a Nye channel
Moulin kame
Mound of debris accumulated at the bottom of a moulin
Ice marginal (ice contact)
Ice-marginal
stream erosion
Meltwater (or hillside)
channel
Meltwater channel tending to run along the side of a cold glacier
Overflow channel
Meltwater channel cut by marginal stream overtopping low cols at or
below the ice-surface level
Continued
