Glossary

=Important Terms:=


 * Ablation zone:** The area of a glacier where mass is lost through melting or evaporation at a greater rate than snow and ice accumulate.
 * Accumulation zone:** The area of a glacier where mass is increased through snowfall at greater rate than snow and ice is lost through ablation.
 * Arête**: A sharp-edged ridge of rock formed between adjacent cirque glaciers**.**
 * Basal sliding:** The sliding of a glacier over the ground on a layer of water.
 * Cirque:** A bowl-shaped depression carved out of a mountain by an alpine glacier.
 * Continental glacier:** A glacier that forms over large areas of continents close to the poles.
 * Crevasse:** A deep, nearly vertical crack that develops in the upper portion of glacier ice.
 * Erosion:** The gradual wearing away of Earth surfaces through the action of wind and water.
 * Erratic:**A large boulder that a glacier deposits on a surface made of different rock.
 * Esker:** A long, snakelike ridge of sediment deposited by a stream that ran under or within a glacier.
 * Firn:** The granular ice formed by the recrystallization of snow; also known as névé.
 * Fjord:** A deep glacial trough submerged with seawater.
 * Glacial drift:** A general term for all material transported and deposited directly by or from glacial ice.
 * Glacial polish:** The smooth and shiny surfaces that are produced on rocks underneath a glacier by material carried in the base of that glacier.
 * Glacial surge:** The rapid forward movement of a glacier.
 * Glacial trough:** A U-shaped valley carved out of a V-shaped stream valley by the movement of a valley glacier. **Glaciation:** The transformation of the landscape through the action of glaciers.
 * Glacier:** A large body of ice that formed on land by the compaction and recrystallization of snow, survives year to year, and shows some sign of movement downhill due to gravity.
 * Ground moraine:** A continuous layer of till deposited beneath a steadily retreating glacier.
 * Hanging valley:** A shallow glacial trough that leads into the side of a larger, main glacial trough.
 * Horn:** A high mountain peak that forms when the walls of three or more glacial cirques intersect.
 * Internal flow:** The movement of ice inside a glacier through the deformation and realignment of ice crystals; also known as creep.
 * Kame:** A steep-sided, conical mound or hill formed of glacial drift that is created when sediment is washed into a depression on the top surface of a glacier and then deposited on the ground below when the glacier melts away.
 * Kettle:** A shallow, bowl-shaped depression formed when a large block of glacial ice breaks away from the main glacier and is buried beneath glacial till, then melts. If the depression fills with water, it is known as a kettle lake.
 * Lateral moraine:** A moraine deposited along the side of a valley glacier.
 * Medial moraine:** A moraine formed when two adjacent glaciers flow into each other and their lateral moraines are caught in the middle of the joined glacier.
 * Meltwater:** The water from melted snow or ice.
 * Moraine:** A general term for a ridge or mound of till deposited by a glacier.
 * Piedmont glacier:** A valley glacier that flows out of a mountainous area onto a gentle slope or plain and spreads out over the surrounding terrain.
 * Rock flour:** Fine-grained rock material produced when a glacier abrades or scrapes rock beneath it.
 * Snow line:** The elevation above which snow can form and remain all year.
 * Striations:** The long, parallel scratches and grooves produced in rocks underneath a glacier as it moves over them.
 * Tarn:** A small lake that fills the central depression in a cirque.
 * Terminal moraine:** A moraine found near the terminus of a glacier; also known as an end moraine.
 * Terminus:** The leading edge of a glacier; also known as the glacier snout.
 * Till:** A random mixture of finely crushed rock, sand, pebbles, and boulders deposited by a glacier.
 * Valley glacier:** An alpine glacier flowing downward through a preexisting stream valley.

All of these terms can be found at [|scienceclarified.com].