GEOL: Geol. 1403/Cook quiz 13 Flashcards

Which process occurs where a glacier enters the sea?

a) kaming

b) calving

c) surging

d) drowning

The ____ of the geologic time scale represents the time of the most recent "Ice Age".

a) Pleisocene era

b) Pliocene era

c) Pleistocene epoch

d) Pliocene era

____ is one of two major flow mechanisms in a glacier.

a) Basal slip

b) Crevassal slip

c) Frost heaving

d) Morainal sliding

Where is the world's largest icesheet located today?

a) Greenland

b) Russia, Siberia

c) Iceland

d) Antarctica

Approximately how long ago did the last of the great North American ice sheets melt?

a) 1,500 yrs

b) 1.5 million yrs

c) 15,000 yrs

d) 150,000 yrs

A fjord is ____.

a) a stream valley, deepened by glacial erosion, that floods as sea level rises

b) a glacier-cut valley that is dammed by an end moraine and a large lake is formed

c) a glacier-cut valley which sinks below sea level due to glacial rebound after the ice melts

d) a large, kettle pocked moraine left as an island when sea level rises following melting of the ice.

Where is the world's second largest continental icesheet?

a) Iceland

b) Greenland

c) Antarctica

d) Siberian Russia

A(n) ____ is simialr in appearance to a sinkhole of a karst area.

a) moraine

b) esker

c) cirque

d) kettle

Abrasion and plucking generally involve what part of a glacier?

a) the internal, flowage zone

b) the snout zone

c) the surface, brittle zone

d) the basal, sliding zone

A ____ cross-valley profile is typical of canyons and valleys eroded and deepened by alpine or valley glaciers.

a) U

b) Y

c) V

d) S

____ are erosional features produced by vallet/alpine glaciers.

a) moraines

b) cirques

c) eskers

d) drumlines

A ____ is an erosional feature specifically produced by alpine glaciation.

a) lateral morain

b) drumlin

c) crevasse spur

d) U-shaped valley

A(n) ____ is likely to host a waterfall or steep rapids today.

a) outwash plain

b) hanging valley

c) striated drumlin

d) horn peak

A ____ would logically be situated next to a large end moraine or terminal moraine.

a) cirque

b) fjord

c) pluvial lake

d) outwash plain

Which of the following is often associated with a cirque basin in high, mountainous terrain?

a) loon lake

ba) kettle pond

c) tarn lake

d) arete pond

____ is an irregular, usually thin till layer laid down by a retreating glacier.

a) terminal morain

b) outwash blanket

c) kame sheet

d) ground moraine

All of the following are thought to possibly contribute to the formation of glaciers except for ____.

a) eccentricity

b) precession

c) comets

d) plate tectonics

Which of the following best describes the term glacial drift?

a) floating of icebergs southward from the north polar seas

b) slow, plastic flow movement in the brittle zone of a glaciar

c) the sedimentary materials outwash and till

d) the slow, southward advance of the continental icesheets over Canada and North America during the Pleistocene

Which of the following statements concerning glacial deposits is not true?

a) till is deposited directly from the ice, outwash is depositd by meltwater streams

b) glacial erratics are blocks of rock that are too large for the glacier to move

c) tills are poorly sorted and the fragments are mostly angular

d) outwash is mainly stratified sand and gravel

What type of moraine is formed by the merging of two lateral moraines at a junction of two valley glaciers?

a) medial

b) recessional

c) ground

d) kettle

T/F When aglacier is retreating, the upstream ice is still moving forward toward the downstream terminus of the glacier.

T/F Crevasses are short, narrow cracks in the plastic flow zone of a glacier that alternately open and close as the ice flows along.

T/F The downstream end or snout of a glacier advances over peiods of time during which ablation exceeds accumulation.

T/F Till is an unsorted sediment deposited directly from the melting glacial ice; stream action is not involved

T/F Arêtes, horns, and U-shaped valleys are erosional features carved from bedrock by glaciers.

T/F Sand and gravel deposited by glacial meltwater streams are known as outwash till or stratified till.

T/F In the north-central United States, much of the land north of the Ohio and Missouri Rivers was covered by one or more of the Pleistocene icesheets.

T/F Surges in glacial movement are probably related to unusually fast rates of basal sliding.

T/F Rock flour consists of silt-sized, rock and mineral particles produced by glacial abrasion.

T/F Eskers and kames are deposited by meltwater streams, they are composed of stratified sand and gravel.

T/F Essentricity, obliquity, and precession are three factors involved in the Milankovitch astronomical explanation of why the Pleistocene continental icesheets alternately grew and sharnk in size.

T/F A cirque represents an erosional feature formed in what was an important accumulation zone for snow and ice at the upstream head of a glacier.

Unusually rapid, forward movement of glaciers are called ____.

a) crevasse

b) U-shaped

c) fjord

d) esker

e) drumlin

ab) kettle

ac) cirque

ad) hanging valley

ae) ablation

bc) fracture

bd) surges

be) plastic flow; basal slip

List the two, major mechanisms of glacial flow.

a) crevasse

b) U-shaped

c) fjord

d) esker

e) drumlin

ab) kettle

ac) cirque

ad) hanging valley

ae) ablation

bc) fracture

bd) surges

be) plastic flow; basal slip

What term describes open fissures in the brittle, surface ice of a gacier?

a) crevasse

b) U-shaped

c) fjord

d) esker

e) drumlin

ab) kettle

ac) cirque

ad) hanging valley

ae) ablation

bc) fracture

bd) surges

be) plastic flow; basal slip

What general term denotes wastage of a glacier?

a) crevasse

b) U-shaped

c) fjord

d) esker

e) drumlin

ab) kettle

ac) cirque

ad) hanging valley

ae) ablation

bc) fracture

bd) surges

be) plastic flow; basal slip

Valleys deeply eroded by alpine glaciers have what characteristic, cross-valley profile?

a) crevasse

b) U-shaped

c) fjord

d) esker

e) drumlin

ab) kettle

ac) cirque

ad) hanging valley

ae) ablation

bc) fracture

bd) surges

be) plastic flow; basal slip

What term denotes a glacial valley that was partly flooded as sea level rose?

a) crevasse

b) U-shaped

c) fjord

d) esker

e) drumlin

ab) kettle

ac) cirque

ad) hanging valley

ae) ablation

bc) fracture

bd) surges

be) plastic flow; basal slip

Bowl-shaped depressions in bedrock at upstream ends of alpine glacial valleys are called ____.

a) crevasse

b) U-shaped

c) fjord

d) esker

e) drumlin

ab) kettle

ac) cirque

ad) hanging valley

ae) ablation

bc) fracture

bd) surges

be) plastic flow; basal slip

The upper 40 meters or so of a glacier is known as the zone of ____.

a) crevasse

b) U-shaped

c) fjord

d) esker

e) drumlin

ab) kettle

ac) cirque

ad) hanging valley

ae) ablation

bc) fracture

bd) surges

be) plastic flow; basal slip

____ are glacier-cut valleys that flooded as sea level rose in post-glacial times.

a) crevasse

b) U-shaped

c) fjord

d) esker

e) drumlin

ab) kettle

ac) cirque

ad) hanging valley

ae) ablation

bc) fracture

bd) surges

be) plastic flow; basal slip

____ are smoothly tapered, elongated hills of till, shaped by an overriding continental icesheet.

a) crevasse

b) U-shaped

c) fjord

d) esker

e) drumlin

ab) kettle

ac) cirque

ad) hanging valley

ae) ablation

bc) fracture

bd) surges

be) plastic flow; basal slip

A(n) ____ is a closed depression formed by melting of an ice block buried in a moraine or outwash plain.

a) crevasse

b) U-shaped

c) fjord

d) esker

e) drumlin

ab) kettle

ac) cirque

ad) hanging valley

ae) ablation

bc) fracture

bd) surges

be) plastic flow; basal slip