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Glacier ice is slightly more dense than ice formed from frozen water because glacier ice contains fewer trapped air bubbles. Glacial ice has a distinctive blue tint because it absorbs some red light due to an overtone of the infrared OH stretching mode of the water molecule. (Liquid water appears blue for the same reason.
Erosional landforms. As the glaciers expand, due to their accumulating weight of snow and ice they crush, abrade, and scour surfaces such as rocks and bedrock.The resulting erosional landforms include striations, cirques, glacial horns, arêtes, trim lines, U-shaped valleys, roches moutonnées, overdeepenings and hanging valleys.
[4] [16] The formation of valley glaciers is restricted by formations such as terminal moraines, which are collections of till (unconsolidated rock material) deposited by the terminus of the glacier. Ice-free exposed bedrock and slopes often surround valley glaciers, [17] providing a route for snow and ice to accumulate on the glacier via ...
Glacial striations are usually multiple, straight, and parallel, representing the movement of the glacier using rock fragments and sand grains, embedded in the base of the glacier, as cutting tools. Large amounts of coarse gravel and boulders carried along underneath the glacier provide the abrasive power to cut trough-like glacial grooves.
A glacier is an extended mass of ice formed from snow falling and accumulating over a long period of time; glaciers move very slowly, either descending from high mountains, as in valley glaciers, or moving outward from centers of accumulation, as in continental glaciers.
The Late Cenozoic Ice Age began 34 million years ago, its latest phase being the Quaternary glaciation, in progress since 2.58 million years ago. Within ice ages, there exist periods of more severe glacial conditions and more temperate conditions, referred to as glacial periods and interglacial periods, respectively.
Plucking – pieces of bedrock are cracked off by glaciers, producing larger erratics. Ice thrusting – the glacier freezes to its bed, moving large sheets of frozen sediment at its base along with it. Glacially induced spalling – layers of rock are spalled off the rocks below the glacier during ice lens formation. This provides smaller ...
The term "glacial series" is restricted to landforms created by glaciers and classified by geomorphological rules, as opposed to the glacial sediments and sedimentary rocks associated with glaciers and classified by their geological features. A complete glacial series is formed when the edge of the ice sheet remains static for a long time and ...