Geology Final Exam Study Guide
GSCI Final Exam Study Guide
Glaciers q 1-24 34% Text book p 570-587 Ice as a Rock - Mass of crystalline grains of the mineral ice - Like sedimentary: formed from material in deposited layers, can accumulate a great Thickness - Igneous: formed by the freezing of a fluid - Metamorphic: transformed by recrystallization under pressure - Flows readily downhill like a viscous fluid because of structural weakness - Glaciers: large masses of ice on land that show evidence of being in motion or of once Having moved under the force of gravity
- Valley/Alpine Glaciers : Rivers of ice formed in cold heights of mountain ranges where snow accumulates and then move down slope in an existing stream valley or carving a new one. Usually occupies the complete width of the valley and may bury its floor under hundreds of meters of ice.
- Iceberg Calving: masses of ice break off glaciers that terminate at ocean’s edge and form icebergs
- Continental glacier: thick slow moving sheet of ice (ice sheet) that covers a large part of a continent or some other land mass.
- Greenland, Antarctica, 10% of Earth’s land, 75% fresh water.
- Ice shelves: thinner sheets of ice floating on the ocean and attached to the main glacier on land How Glaciers Form
- Abundant winter snowfall that does not melt, slowly converted to ice, when thick enough it begins to flow
- Snow line: elevation at which snow does not melt in the summer. Lower near poles
- Unlikely to form in arid climates because of need for moisture, except Antarctica because nothing ever melts
- Over time snow accumulates and compacts
- Snow (90% air) granular ice (50%) firn (20-30%)glacial ice (20% as bubbles) - May only take a few years, 10 to 20 more likely - Accumulation: amount of ice added to a glacier annually - Ablation: total amount of ice a glacier loses annually 1. Melting - #1 2. Iceberg calving - #2 3. Sublimation – water directly from ice to water vapor
Glaciers q 1-24 34% Text book p 570-587 Ice as a Rock - Mass of crystalline grains of the mineral ice - Like sedimentary: formed from material in deposited layers, can accumulate a great Thickness - Igneous: formed by the freezing of a fluid - Metamorphic: transformed by recrystallization under pressure - Flows readily downhill like a viscous fluid because of structural weakness - Glaciers: large masses of ice on land that show evidence of being in motion or of once Having moved under the force of gravity
- Valley/Alpine Glaciers : Rivers of ice formed in cold heights of mountain ranges where snow accumulates and then move down slope in an existing stream valley or carving a new one. Usually occupies the complete width of the valley and may bury its floor under hundreds of meters of ice.
- Iceberg Calving: masses of ice break off glaciers that terminate at ocean’s edge and form icebergs
- Continental glacier: thick slow moving sheet of ice (ice sheet) that covers a large part of a continent or some other land mass.
- Greenland, Antarctica, 10% of Earth’s land, 75% fresh water.
- Ice shelves: thinner sheets of ice floating on the ocean and attached to the main glacier on land How Glaciers Form
- Abundant winter snowfall that does not melt, slowly converted to ice, when thick enough it begins to flow
- Snow line: elevation at which snow does not melt in the summer. Lower near poles
- Unlikely to form in arid climates because of need for moisture, except Antarctica because nothing ever melts
- Over time snow accumulates and compacts
- Snow (90% air) granular ice (50%) firn (20-30%)glacial ice (20% as bubbles) - May only take a few years, 10 to 20 more likely - Accumulation: amount of ice added to a glacier annually - Ablation: total amount of ice a glacier loses annually 1. Melting - #1 2. Iceberg calving - #2 3. Sublimation – water directly from ice to water vapor