How glaciers form and move, and the landforms left behind by glaciation, from an intro geology course.
30 cards · basic cards · AI-written, checked twice. Edit anything.
- What is a glacier?
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A large, persistent mass of ice and snow that flows under its own weight.- What three stages transform snow into glacial ice?
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Accumulation (snow falls), compaction (weight increases density), recrystallization (ice crystals grow larger and air is expelled).- What is neve?
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Compacted granular snow intermediate between snow and glacial ice, with density between the two.- Define equilibrium line altitude (ELA).
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The elevation where annual accumulation equals annual ablation on a glacier's surface.- What is a valley glacier?
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A glacier confined to and flowing down a mountain valley, also called an alpine glacier.- What is a continental glacier?
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A large ice sheet covering vast continental areas, such as those presently in Greenland and Antarctica.- What is a piedmont glacier?
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A glacier formed where valley glaciers emerge from mountain valleys and merge on the adjacent plains.- What is a cirque glacier?
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A small glacier occupying a bowl-shaped or amphitheater-shaped depression in high mountains.- How does plastic flow move a glacier?
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Ice at depth deforms under pressure and flows plastically downslope without melting, like very slow viscous flow.- What is basal sliding?
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Glacial movement in which ice at the base of a glacier lubricates and slides over bedrock, typically when meltwater is present.- What is a glacial erratic?
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A large boulder transported by glacial ice and deposited far from its source rock outcrop.- What is a cirque?
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A bowl-shaped or amphitheater-shaped depression carved by glacial erosion at the head of a mountain valley.- What is a U-shaped valley?
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A valley with steep walls and a flat floor, carved by glacial erosion, contrasting with V-shaped river valleys.- What is a hanging valley?
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A tributary valley whose floor is higher than the main glacier valley it joins, often with a waterfall where they meet.- What is a moraine?
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A ridge or mound of sediment deposited directly by glacial ice, containing unsorted, unstratified material.
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