piedmont glacier
Học thuậtThân thiện
Definition
Noun: A piedmont glacier is a broad, gently sloping ice sheet formed when one or more alpine (valley) glaciers flow out of a mountainous area and spread onto a relatively flat plain at the base of the mountains.
Usage
The term is used in geology and glaciology to describe a specific formation where confined mountain glaciers coalesce into a single, unconfined ice mass upon reaching a flatland.
Examples
- The Malaspina Glacier in Alaska is a classic example of a piedmont glacier.
- Scientists study the movement of the piedmont glacier to understand ice dynamics at the edge of mountain ranges.
- The formation of a piedmont glacier requires specific topographic conditions where a valley opens onto a plain.
Advanced Usage
- Formation Process: The term describes the stage where the ice flow transitions from being channelized to unconfined, often creating a distinctive lobate shape.
- Scientific Context: In research, the health and retreat of a piedmont glacier can be an indicator of regional climate change.
Variants and Related Words
- Piedmont (noun, often capitalized): A geographic term for an area at the base of a mountain or mountain range. The glacier type is named after this landform.
- Valley Glacier (noun): A glacier that flows down a valley from an ice cap or ice field; it is the primary feeder for a piedmont glacier.
- Ice Sheet (noun): A mass of glacial ice that covers surrounding terrain; a piedmont glacier is a type of ice sheet, but on a much smaller scale than continental ice sheets.
Synonyms
- Piedmont ice sheet
- Expanded-foot glacier (less common technical term)
Related Concepts (Not Phrasal Verbs or Idioms)
- Glaciation: The process, condition, or result of being covered by glaciers.
- Stagnant ice: Refers to parts of a piedmont glacier with very slow or no movement, as mentioned in some definitions.
- Terminus: The lower end of a glacier, which for a piedmont glacier is often a wide, irregular front.
Noun
- a type of glaciation characteristic of Alaska; large valley glaciers meet to form an almost stagnant sheet of ice