Geography 323 -- Geomorphology

Glacial Landforms

Erosional landforms

Ice sheets

ice scoured basins
the Great lakes and millions of other lakes basins on the Canadian shield and other glaciated shields

roche mountonnees
"rock sheep", bedrock ridges striated and polished on the stoss (up-glacier) side and plucked on the lee side where meltwater produced on the stoss side refroze to the lee side of the ridge

meltwater valleys
large wide valleys eroded by meltwater draining along the ice margin or spillways draining glacial lakes (e.g. all the major valleys of the southern Canadian Interior Plains)

Mountain glaciers

bowl-shaped rock cavity, where alpine glaciers form and then retreat to and persist; commonly have small lakes called tarns

narrow ridge between glacial cirques and troughs
pyramidal peak faceted by glaciation on all sides

hanging valley
tributary valley that hangs above the trunk valley, i.e. the floors of the two valley are a t different elevation and separated by a cliff (and thus usually waterfalls)

glacial trough
the U-shaped valley created when a valley glacier, usually by modifying a pre-glacial fluvial (V-shaped) valley

truncated spur
the ends of interfluves truncated by valley glaciation

Glacial deposits

glacial drift
all sediment transported by glaciers or glacial meltwater

unsorted, unstratified drift deposited directly from glacier ice

ice-contact stratified drift
deposited or modified by meltwater in contact with or close proximity to ice; some sorting and stratification but large variation in particle size and sedimentary structure

glacial-fluvial sediments washed out from the margin of the ice with more sorting than with ice-contact drift

glacio-lacturine sediments
clays and silts deposited in lakes near or on glaciers

glacio-marine sediments
sediment rained down or ice rafted onto continental shelves from a floating glacier

glacio-tectonic drifto
frozen or saturated drift and/or bedrock folded and faulted by the force of a glacier

Depositional landforms

collective term for landforms of direct glacial origin