Final Exam Review Pt 1

Question 1

talik

Answer 1

Unfrozen ground that may occur above, below, or within a body of discontinuous permafrost OR beneath a water body in the continuos region. They form connections between the active layer and the groundwater.

Question 2

lacustrine deposits

Answer 2

The drier periods between pluvials, called interpluvials, are marekd by lacustrine deposits.

Question 3

paleolakes

Answer 3

Ancient lakes (also known as pluvial lakes)-

Question 4

ice age

Answer 4

A term applied to any extended period of cold (not a single, brief cold spell). It includes one or more glacials, interrupted by a brief warm spell known as interglacials.

Question 5

Patterned Ground

Answer 5

The expansion and contraction of frost action makes soil particles, stones and small boulders move.

Question 6

Ground Ice

Answer 6

Frozen subsurface water

Question 7

Active Layer

Answer 7

The active layer is the zone of seasonally frozen ground that exists between the subsurface permafrost layer and the ground surface. Higher temperatures increase the thickness of the active layer. Cold temperatures increase permafrost depth and reduce the active layer.

Question 8

What latitudes will you find periglacial climates?

Answer 8

Either high latitude (tundra and boreal forest environments) or at high elevation in lower-latitude mountains (alpine environments).

Question 9

Define periglacial and list three periglacial processes.

Answer 9

Periglacial refers to the frost weathering and freeze thaw. They have a near-permanent ice cover or at a high elevation and are seasonally snow free Three periglacial processes are permafrost, frost action, and ground ice.

Question 10

What are the two categories of permafrost?

Answer 10

Periglacial refers to the frost weathering and freeze thaw. They have a near-permanent ice cover or at a high elevation and are seasonally snow free Three periglacial processes are permafrost, frost action, and ground ice.

Question 11

Permafrost

Answer 11

Develops when soil or rock temperatures remain below freezing for at least two years. Two factors that contribute to permafost: the presence of fossil permafrost and snow on the surface that inhibits heating.

Question 12

Drumlin

Answer 12

One of two types of streamlined hills. Deposited till that was streamlined in the direction of continental ice movement, blunt end upstream and tapered end downstream.

Question 13

Roche Moutonnee

Answer 13

One of two types of stremlined hills. Its an asymmetrical hill of exposed bedrock. It slopes gently upstream and downside it is steep.

Question 14

Kame

Answer 14

Another feature of an outwash plain, a small hill or mound of poorly sorted sand and gravel that is deposited directly by water or by ice in crevasses or in ice-caused indentations in the surface. ]

Question 15

Kettle

Answer 15

Sometimes a block of ice remains after the glacier has retreated. As it melts, material continues to surround the melting ice block. A kettle is what is left over; a steep-sided hole.

Question 16

Esker

Answer 16

A curving, narrow ridge of coarse sand and gravel. It forms along the channel of a meltwater stream that flows beneath a glacier, in an ice tunnel, or between ice walls. When a glacier retreats, the esker is left behind.

Question 17

Outwash Plains

Answer 17

Beyond the morainal deposits, stratified drift, with stream channels that are meltwater-fed, braided, and overloaded with sorted and deposited materials.

Question 18

Till Plain

Answer 18

A till plain forms behind an end moraine; it features instratified coarse till, has low and rolling relief, and a deranged drainage pattern.

Question 19

Terminal Moraine

Answer 19

Formed when eroded depris is dropped at the glacier’s farthest extent.

Question 20

Medial Moraine

Answer 20

When two lateral moraines join, they form a medial moraine.

Question 21

Lateral Moraine

Answer 21

forms along each side of a glacier.

Question 22

Name and describe the three types of moraines.

Answer 22

Lateral, medial and terminal moraines.

Question 23

Moraines

Answer 23

Landforms created by the deposition of glacial sediment.

Question 24

Till

Answer 24

Unsorted debris deposited on the ground surface as a glacier flows to a lower elevation.

Question 25

Stratified Drift

Answer 25

Sediments deposited by glacial meltwater are sorted by size and are stratified drift.

Question 26

Glacial Drift

Answer 26

The general term for all glacial deposits, both unsorted and sorted.

Question 27

What are four features of alpine glaciers?

Answer 27

Aretes, col, horn, tarn, paternoster lakes, fjords

Question 28

Fjord

Answer 28

As the glacier retreats, the trough floods and forms a deep fjord in which the sea extends inland, filling the lower reaches of the steep sided valley.

Question 29

Paternoster Lakes

Answer 29

Small, circular, stair-stepped lakes, named for their resemblance to prayer beads.

Question 30

Tarn

Answer 30

Small mountain lakes in the cirques where the valley glaciers originated.

Question 31

Horn

Answer 31

A pyramidal peak that results when several cirque glaciers gouge an individual mountain summit from all sides .

Question 32

Col

Answer 32

Two eroding cirques may reduce an arete to a saddle like depression or pass, forming a col.

Question 33

Aretes

Answer 33

Knife-edge ridges that form as cirque walls erode away, divide adjacent cirque basins.

Question 34

Abrasion

Answer 34

When glaciers move, they pick up rocks that become embedded in the basal layer, which scour through abrasion and sandpaper the landscape, leaving behind a smooth surface.

Question 35

Glacier Surge

Answer 35

When glaciers lurch forward without warning. Glaciers are surging overall (there is a doubling of ice-mass loss, so water works its way to the basal layer, lubricating underlying soft beds of clay)

Question 36

Crevasses

Answer 36

A flowing alpine glacier or an ice stream in a continental glacier can develop vertical cracks known as crevasses.

Question 37

Basal slip

Answer 37

The base movement of a glacier, much less rapid than the internal plastic flow of the glacier, so the upper portion of the glacier flows ahead of the lower portion.

Question 38

What does it mean to say that a glacier is plastic?

Answer 38

Glaciers are pliable; they distort and flow in its lower portions in response to weight and pressure form above and the degree of the slope below.

Question 39

Ablation

Answer 39

At the end of the glacer, its reduced in size through ablation, the collection of several process– melting (internally, surface and base), ice removal by deflation (wind), calving of ice blocks, and sublimation (the direct evaporation of ice).

Question 40

Firn line

Answer 40

Snowfall and other moisture in the accumulation zone feed the glacier’s upper reaches. This area ends at the firn line, indicating where the winter snow and ice accumulation survived the melting season.

Question 41

Glacial Ice

Answer 41

Analagous to metamorphic processes: Sediments (snow and firn) are pressured and recrystallized into a dense metamorphic rock (glacial ice).

Question 42

Firn

Answer 42

In the transition step to glacial ice, snow becomes firn, which has a compact, granular texture.

Question 43

What is a glacier’s mass budget?

Answer 43

Consists of net gains or losses of the glacial ice, which determines whether the galcier expands or retreats. Glaciers grow when its cold with lots of precipitation, it gets smaller when it has a negative net balance. Note: gravity moves glaciers forward even though its lower terminus might be in retreat owing to ablation.

Question 44

How are glaciers formed?

Answer 44

Compaction, recrystallization and growth of snow and water. The essential input is snow that accumlates in a snowfield, a glacier’s accumulation zone. As snow accumulates, the increasing thickness results in greater pressure on underlying ice. Rain and snow melt, contribute water, and then freeze. Air spaces condense as snow is packed to a greater density. Ice recrystallizes and consolidates under pressure.

Question 45

Ice Field

Answer 45

Not extensive enough to form the dome of an ice cap; it extends in an elongated pattern in a mountainous region.

Question 46

Ice Cap

Answer 46

A roughly circular, covers an area of less than 50,000 km. It buries the underlying landscape completely.

Question 47

Ice Sheet

Answer 47

The most extensive form of continental glacierl most of the Earth’s ice exists in the ice sheets that blanket Antarctica and Greenland.

Question 48

Continental Glacier

Answer 48

A continuous mass of ice, much larger than individual alpine glaciers.

Question 49

Icebergs

Answer 49

Pieces of floating ice, resulting from tidal glaciers that calve into the sea.

Question 50

Piedmont Glacier

Answer 50

Wherever several valley glaciers pour out of their confining vallies and coalesce at the base of a mountain range, a piedmont glacier is formed and spreads freely over the lowlands.

Question 51

Cirque

Answer 51

A bowl-shaped erosional landform called a cirque, which contains snowfields. A glacier that forms in a cirque is called a cirque clacier. Cirque glaciers may also feed valley glaciers.

Question 52

Snowfield

Answer 52

The area of origin of an apline glacier;it is confined in a cirque

Question 53

Alpine Glacier

Answer 53

A glacier in a mountain range. If its an alpine glacier in a valley, then it’s a valley glacier.

Question 54

Valley Glacier

Answer 54

An alpine glacier found in a valley

Question 55

Snowline

Answer 55

The lowest elevation where snow can survive year-round;it is the lowest line where winter snow persists in summer.

Question 56

Glacier

Answer 56

A large mass of ice resting on land or floating as an ice shelf in the sea adjacent to land. Glaciers cover 11% of land (down from 30% of continental land).

Question 57

Cryosphere

Answer 57

The portion of the hydrosphere and groundwater that is perennially frozen, generally at high latitudes and elevations. It is in a state of dramatic change as glaciers and ice melt.