Alpine And Continental Glaciation

Question 1

How do glaciers form?

Answer 1

Snow accumulation exceeds the annual melt

Snow crystals change over time and become compacted into ice.

Question 2

What are the two main areas/parts of glaciers?

Answer 2

Zone of accumulation where snowpack increases in size
Zone of ablation where it begins to melt.

When a glacier is growing the area of accumulation expands
When a glacier recedes the area of ablation takes up a greater percentage of the glaciers size

Question 3

What is a bergschrund?

Answer 3

Ice stuck to the mountain separates itself from the glacier slowly ,moving

Question 4

What is a nunatak?

Answer 4

Piece of rock sticking out of a glacier.

Question 5

What are some of the effects of glacial erosion?

Answer 5

Ice and debris scouring rock and produce striations and glacial polish

Rochester moutoneee: feature where till material builds up on one side and is plucked on the other, can indicate direction of the glacial flow

Question 6

What are the results of glacial transportation?

Answer 6

All shapes and sizes of material carried, non selective
Carries debris fallen atop
Plucked material
And eroded material

Question 7

What are the details of glacial deposition?

Answer 7

Glacial deposits are called till or moraine

Unstratifieda poorly sorted material. coarse fragments are usually sub angular.

Mounds and ridges adjacent to glaciers are called
Lateral
Medial
Terminal = at the bottom of glaciers, can dam up lakes/rivers

Question 8

What height were the glaciers in our region 10,000 years ago?

Answer 8

Around 7,000 feet/2100 meters.

Question 9

What is an arete?

Answer 9

A knife edge or steep ridges between two glaciers.
Created by glaciation and partially frost action
Glaciers on both sides erode both sides, frost action and other weathering creates a sharp feature.

Question 10

What is a cirque?

Answer 10

A bowl shape at the back of a valley shaped by a small glacier
Ice scouring and depressions created
Creates small lakes that are called tarn lakes

Question 11

What is a horn?

Answer 11

Type of peak sharpened over time by frost action
Glaciers on the sides of it that wear down the sides and creates a pyramid shaped mountain

Frost action plays a huge role over time in shaping features

Question 12

What is a col or pass?

Answer 12

Formed when 2 glaciers erodes and cuts through a ridges, can be 2 glacies on either side of a mountain or a larger continental glacier

Question 13

What forms a u shaped valley?

Answer 13

Valley formed by a glacier eroding the landscape

U shaped = glacier formed. Flat bottom, steeper sides.
V shaped = moving water

Question 14

What are hanging valleys?

Answer 14

Valley that ends in a deep cut off.
Formed when a valley shaped by a glacier intersections another glacier forming a larger valley at a perpendicular intersection

Question 15

What is a truncated spur?

Answer 15

Sudden end of a ridge turning a face, often found alongside forming a hanging valley.

Question 16

What is a finger lake?

Answer 16

When a u shaped valley is dammed and long lakes form. Contained by the valley walls on both sides.

Landslides or terminal moraines help form these

Question 17

What are fjords?

Answer 17

Formed by glaciated valleys that fill with sea water along the coast as the oceans rise.

Question 18

How is moraine defined?

Answer 18

Material left after the glaciers melted
No sorting
Randomly deposited coarse fragments, can have a mix of sand and silt and clay

Question 19

What is a drumlins?

Answer 19

Streamlined hills 15 to 100ms with high
Indicate the direction of a flow of a continental glacier
Hill tapers off in the direction of the flow

Not bedrock, morainnal material.
It is an accumulation of till.

Question 20

What are erratics?

Answer 20

Large boulders that are transported many kilometers away by glaciers and deposited when ice recedes
Often found quite isolated

Question 21

The distinction between glacial fluvial and morainnal material?

Answer 21

Glacialfluvial involv3s the movement of water

Question 22

What is an outwash plain?

Answer 22

Braided streams emerge from terminus of glaciers
Very braided due to high bedload of water

Question 23

What are eskers?

Answer 23

A sinuous ridges that forms from streams that flow under glacier ice
They get plugged up and material accumulates
Glacier melts and esker remains

Snake like, deposited by moving material so you’ll find more rounded material - glacialfluvial material. No fines (silt and clays)

Question 24

What is a kame terraces?

Answer 24

Formed by a material that is washed down by the sides of a valley and deposited next to a glacier
Ice is adjacent to the terrace
It has kettle holes, that’s how yountell

Question 25

What is a kettle hole

Answer 25

Ice chunk breaks off
Material accumulates around the ice chunk
Ice melts and leaves a hole
Lakes can form in them aka kettle lake

Question 26

What are eolian deposits?

Answer 26

Carried by wind
No coarse fragments