Year 9 Geography Knowledge Test 4 - Glaciation

Vocabulary practice flashcards covering key terms and concepts from Year 9 Knowledge Test 4 on glaciers and glaciation.

Fresh water glacial storage

70 per cent of the world's fresh water is stored in the world's glaciers.

Glacial land coverage

One-tenth of the Earth's land area is covered by glaciers.

Alpine glacier

A glacier that forms on a mountainside and moves down-slope through a valley.

Glacial formation condition

The condition where temperatures throughout the year are not high enough to melt the previous winter's build-up of snow.

Glacials

Periods during an ice age when ice advances.

Interglacials

The periods of warmer climate between ice advances.

Last ice age extent

During the last ice age, three times as much land was covered by ice compared to present levels.

Zone of accumulation

The area on a glacier where snow builds up and slowly turns into ice.

Zone of ablation

The region on a glacier where ice melts faster than it accumulates.

Snout

The front end or terminus of a glacier.

Plucking

The process where loosened pieces of bedrock become frozen to the base of glacial ice and move with it.

Freeze-thaw

A type of weathering that loosens rock at the bottom and surrounding areas of glacial ice, allowing it to become entrained.

Abrasion

The erosion process where rocks carried in the base of glacial ice scrape over the ground surface, removing material and smoothing larger rocks.

Striations

Scratches left behind on bedrock as glaciers move through an area, which provide clues to the direction of ice movement.

Moraine

The general name for material carried and deposited by glacial ice, ranging in size from huge angular boulders to fine clay.

Tarn

A lake formed in a glacially carved depression (also referred to as a lochan or corrie lake).

Hanging valley

A tributary valley elevated above the main U-shaped valley floor, often marked by a waterfall.

Glacial impact on river valleys

The transformation of a valley by moving glacial ice, making it larger, straighter, and deeper.