Surface/Exterior Processes

Question 1

What are Alluvial fans and how do they form?

Answer 1

Form when a steep mountain stream reaches dry level land at the base. Dry level land slows down the stream’s velocity and much of the sediment load is dropped.

Question 2

What is an aquifer?

Answer 2

Layer of rock and sediment that carries water which can supply wells

Question 3

What are Carol attols and how do they form?

Answer 3

Ring-shaped island of coral. Formed when:
Fringing reef of coral surrounds volcanic island
Fringing reef becomes barrier reef as it grows above sea level. Volcanic island will sink and barrier reef will contain a lagoon.
Island eventually be completely submerged. Barrier reef surrounding lagoon without volcanic island called Carol atoll.

Question 4

What is calving?

Answer 4

Process of glaciers reaching sea and large chunks fall to form icebergs

Question 5

What is a channel?

Answer 5

The path which water flows in a river or stream

Question 6

What is the Coriolis effect? What are it’s affects and where is it the greatest?
(Hint: There are 5)

Answer 6

Tendency of an object moving over Earth’s surface having a curved trajectory.
Char of Coriolis Effect:
Weakest at equators and strongest at the poles
Effect increases as objects speed increases
Large distances are required for effect to be noticable
N. Hemi. objects deflect to the right S.Hemi. to the left
N.Hemi. high pressure systems spin clockwise and low spinnig counter clockwise. Opposite in S. Hemi
Causes hurricanes to spin counterclockwise in N. Hem and clockwise in S.Hem

Question 7

What are Crevasses and where are they found?

Answer 7

Cracks or fissures near surface of a glacier. Form across width of the glacier

Question 8

What are drumlins?

Answer 8

Long, smooth canoe-shaped hills. Formed when advancing glacier moves over earlier glacier moraine. Point in the direction of glacier advancement

Question 9

What is the Ekman Transport and how does it work?

Answer 9

Effect of net water movement being perpendicular to the wind direction.
Note: For N.Hemi: Upwelling winds cause E.T to be away from land.
Downwelling winds cause E.T to be towards land
Index Finger: Points in wind
Middle Finger: Points up away from water
Thumb: Points to direction of E.T

Question 10

What is Erosion and give examples of it

Answer 10

Removal and transport of rocks or soil by the action of water, ice or wind.

Question 11

What is an Esker?

Answer 11

A long winding ridge of glacier deposit formed as glacier melts

Question 12

What is Fetch and how does it affect the size of lakes?

Answer 12

Length of open water that winds constantly blows over

Larger fetch = Larger height of waves

Question 13

What is a firn?

Answer 13

A rough granular ice material that forms as buried snow becomes thicker and is compressed that it recrystallizes.
Can be turned into solid ice from weight above it. Once it starts flowing outward or downward it’s a glacier

Question 14

What is a fjord?

Answer 14

A deep, long, steep-sided bay made from the sea flooding a glacier trough

Question 15

What are geysers?

Answer 15

Hot spring that shoots out hot water into the air. Caused by superheated water quickly expanding producing burst of steam

Question 16

What is hardwater and what causes it?

Answer 16

Water that has large amounts of ions from dissolved minerals such as Calcium, iron and magnesium

Question 17

What is a floodplain?

Answer 17

The valley floor where the river travels

Question 18

How do levees form?

Answer 18

Thick deposits which have built up along the stream banks

Embankment built to prevent overflow of a river

Question 19

What are meanders and how do they form?

Answer 19

A back and forth sharp board curve in a river.

Due to the fast moving water at the outside of the river bend which causes rapid erosion

Question 20

What are oxbow lakes and how do they form?

Answer 20

A lake that is formed as meanders are cut off during floods as the river drops mud and silt at the ends of the meander
Meander is eventually separated from the river and an oxbow lake is formed

Question 21

What are Kames?

Answer 21

A steep-sided mound of sand and gravel deposited by a melting ice sheet

Question 22

What is Mass Movement?

Answer 22

The down slope movement of weathered earth materials under the influence of gravity

Question 23

List and describe the various conditions that cause mass movement

Answer 23

Volcanic Activity: Repeatded leads to huge mudflows when icy cover of a volcano melts and mixes with the soil to form mud as the magma in the volcano stirs
Mudslides: Develops when water rapidly accumulates in the ground, changing the Earth into a flowing river of mud and “slurry”
Earthquake Shocks: Cause sections of mountains and hills to break off and slide down
Human Modification: Of the land or weathering and erosion help loosen large chunks of Earth and start sliding downhill
Human Caused Vibrations: From machinery, traffic, weight loading for accumulation of snow e.t.c

Question 24

Types of Mass Movement:

Answer 24

Erosion: Removal and transport of rocks or soil by the action of water, ice or wind
Landslide: Movement of bedrock, soil and rock down a slope of a cliff, hill or mountain
Creep: Slow movement of rock debris and soil down a weathered slope. (Causes poles to lean downhill)
Slump: Occurs as the bottom of the slope can not support the top of the slope which becomes unstable
Earthflow: Water saturated weathered material flows downhill. Very slow can take days or years
Mudflows: Fast movements of water containing much clay and silt. Can travel upp to 100 km/h.

Question 25

What are moraines?

Answer 25

Deposit of till left behind when glacier retreats

Question 26

What is a delta and how does it form?

Answer 26

A triangular-like shape deposited at the mouth of a river.
Forms when: velocity greatly slows down at the river’s mouth and the sediments are deposited. Sediments build up and form the delta

Question 27

What are the diff. between alluvial fans and deltas?

Answer 27

Alluvial fans have deposits form on land, delta has water
Alluvial fans have coarse sands and gravels instead of fine silt and clay
Alluvial fans have a sloping surface instead of flat

Question 28

What are potholes and how do they form?

Answer 28

Produced from sand, pebbles and/or small boulders churning in the rocky riverbed from whirlpool action

Question 29

What causes can increase water density in seawater?

Answer 29

Water density increases as salinity increases. Caused by evaporation of water and salt left behind

Question 30

What are the types of glacier lakes?

Answer 30

Kettle Lake: Lake that forms as rain or surface runoff feels a kettle (Bowl-shaped depression)
Moraine-Damned Lake: Lake which are formed as flooding occurs at a spot where river valley is blocked by glacier moraines

Question 31

Normal Conditions vs El Nino

Answer 31

Normal:
Trade winds blow completely across pacific ocean.
Warm water pools above thermocline on western part of pacific ocean
Moist maritime air rises over Indonesia and cools causing rain
Coast of Peru has cold upwelling water full of nutrients producing great fishing area
El Nino:
Trade winds slow down and ocean current switches to opposite direction
Warm water pool moves eastward.
Consistent rain is shifted to middle of Pacific ocean and Indonesia has a draught
Coastal peru waters warm up and have huge decrease in fish

Question 32

What are the two types of Weathering and give examples of each

Answer 32

Weathering: Break up of rock due to exposure to processes on Earth’s surface. Two types are:
Chemical: Decomp. occurs as rock’s mineral changes into a new substance. Ex: Hydrolysis, Oxidation
Mechanical: Disintergration, occurs as rock is broke or spilt into smaller chunks. Ex: Frost Wedging and Exfoiliation

Question 33

What is Wave refraction?

Answer 33

Changing of direction of wave as water depth changes

Question 34

What is a rip current and how dies it form?

Answer 34

Strong surface current which pushes away from beach
Forms at location where an excess of H2O builds up:
2 longshores current meet
Breakers bring in more water than backwash can return
Water is held back by a barrier

Question 35

What is wavelenght?

Answer 35

Horizontal distance of a single wave. Wavelenght over period equals wavespeed

Question 36

What is upwelling and what does it do to fish?

Answer 36

Upwelling: The uplift of cold ocean water to the surface
Upwelled cold water contains high amounts of nutrients and ocean life thrives in these areas. Usually these areas have major commericial fishing

Question 37

What is a turbidity current?

Answer 37

Current that produces sea landslides of mud and sand. Caused by gravity and sometimes earthquake

Question 38

What is Till?

Answer 38

Unsorted and unstratified rock material deposited by glacier ice

Question 39

Describe the four types of sand dunes

Answer 39

Barchans: Winds blow over limited amounts of sand to form half-circles with open ends away from the wind
Parabolic Dunes: Formed around blowouts with half circles with ends facing the wind
Transverse dunes: Form as wind blows over abundant amounts of sand. Dunes are perpendicular to the wind direction
Longitudinal Dunes: Form with moderate amounts of and. Dunes are parallel to wind direction