glaciers and glaciation - exam 2

Question 1

what forms from the accumulation, compaction, and recrystallization of snow?

Answer 1

glaciers

Question 2

dynamic erosional agents that accumulate, transport, and deposit sediment

Answer 2

glaciers

Question 3

glaciers that move slowly and follow the path of valleys originally occupied by streams are called

Answer 3

valley or alpine glaciers

Question 4

when a glacier or ice sheet flows into the ocean, it is called a

Answer 4

tidewater glacier

Question 5

where an advancing tidewater glacier reaches deeper water, the ice will float forming

Answer 5

an ice shelf

Question 6

a type of glacier that completely buries the underlying landscape, but much smaller than ice sheets

Answer 6

ice caps

Question 7

often ice caps and ice sheets feed

Answer 7

outlet glaciers

Question 8

glaciers occupying broad lowlands at the bases of steep mountains and form when one or more alpine glaciers emerge from the confining walls of mountain valleys

Answer 8

piedmont glaciers

Question 9

the type of glacial movement which involves movement within the ice

Answer 9

plastic flow

Question 10

the type of glacial movement where the entire ice mass slips along the ground

Answer 10

basal slip

Question 11

most glaciers are thought to move by the sliding process of

Answer 11

basal slip

Question 12

movement of some glaciers is characterized by occasional periods of extremely rapid advances called

Answer 12

glacial surges

Question 13

snow accumulation and ice formation occur in the

Answer 13

zone of accumulation

Question 14

the elevation at which the accumulation and wasting of glacial ice are equal

Answer 14

snowline or equilibrium line

Question 15

below the snowline is the

Answer 15

zone of wastage

Question 16

the area where there is a net loss to the glacier as all the snow from the previous winter is melting as is the glacial ice

Answer 16

zone of wastage

Question 17

the term for loss of ice by a glacier

Answer 17

ablation

Question 18

the process where glaciers waste away as large pieces of ice break off the front of the glacier

Answer 18

calving

Question 19

what can create icebergs in places where the glacier has reached the sea or a lake?

Answer 19

calving

Question 20

the balance or lack of balance between accumulation at the upper end of the glacier and ablation at the lower end

Answer 20

the glacial budget

Question 21

the process where a glacier flows over a fractured bedrock surface and losses and lifts blocks of rocks and incorporates them into the ice

Answer 21

plucking

Question 22

this process occurs when meltwater penetrates the cracks and joints of bedrock beneath a glacier and freezes

Answer 22

plucking

Question 23

the process where ice and rock fragments advance over bedrock and function as sandpaper, smoothing and polishing the surface below

Answer 23

abrasion

Question 24

the pulverized rock produced by glacial abrasion is called

Answer 24

rock flour

Question 25

when the ice at the bottom of a glacier contains large rock fragments and long scratches and grooves, what may be gouged into the bedrock?

Answer 25

glacial striations

Question 26

valleys of tributary glaciers left standing above the main glacial trough are termed

Answer 26

hanging valleys

Question 27

depressions in bedrock created by plucking and abrasion filled with water

Answer 27

pater noster lakes

Question 28

the focal point of a glaciers growth because its the area of snow accumulation and ice formation

Answer 28

the cirque

Question 29

what begins as irregularities in the mountainside that are enlarged by frost wedging and plucking along the sides and bottom of the glacier

Answer 29

a cirque

Question 30

after a glacier has melted away, the cirque basin is sometimes occupied by a small lake called a

Answer 30

tarn

Question 31

as glacial ice melts and drops its load of rock fragments, what is deposited?

Answer 31

till

Question 32

boulders found in the till or lying free on the surface of the face

Answer 32

glacial erratics if different from the bedrock below

Question 33

what is sorted according to the size and weight of the particles?

Answer 33

stratified drift

Question 34

a widespread feature of glacial deposition of layers or ridges of till

Answer 34

moraine

Question 35

alpine glaciers produce what two types of moraines?

Answer 35

lateral and medial moraines

Question 36

what is created when two alpine glaciers coalesce to form a single ice stream?

Answer 36

medial moraine

Question 37

a ridge of till that forms at the terminus of a glacier

Answer 37

end moraine

Question 38

a gently rolling layer of till deposited as the ice front recedes is termed a

Answer 38

ground moraine

Question 39

in areas that were once covered by continual ice sheets, there is a variety of glacial landscape characterized by smooth, elongate, and parallel hills called

Answer 39

drumlins

Question 40

the sediment acquired and transported by a glacier that is ultimately deposited by streams of glacial meltwater flowing, on, within, beneath, and beyond a glacier is called

Answer 40

stratifed drift

Question 41

most of the major glacial stages occurred during a division of the geologic time scale called the

Answer 41

quaternary period

Question 42

earlier glaciations are indicated by deposits of

Answer 42

tillite

Question 43

a sedimentary rock formed when glacial till becomes lithified

Answer 43

tillite