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World Geography 3202/3200
Unit One: Major Land and Water Forms
Student Notes
Chapter One:
Landform Patterns and Processes
Definitions to know:
Syncline
1.
Volcano
Anticline
Describe how compressional forces are caused.
Compressional forces in the Earth’s crust are caused by the movement of the tectonic plates. These plates
are being moved by the force of convection currents in the layer of molten rock below the crust. When two
plates move toward each other they compact or squeeze together the area between the plates, causing
compressional forces.
2.
Describe how tensional forces are caused.
Tensional forces in the Earth’s crust are caused by the movement of the tectonic plates. These plates are
being moved by the force of convection currents in the layer of molten rock below the crust. When two
plates move away from each other they pull the area between the plates apart, causing tensional forces.
3.
What is the relationship between plate movements and compressional and tensional forces?
On an outline map that shows plate boundaries and the direction of plate movements the following is true:

Where two plates are moving toward each other, there is said to be a compressional force.

Where two plates are moving away from each other or past each other, there is said to be
a tensional force.
4.
Describe how compressional forces create fold mountains.
When two plates move toward each other they compact or squeeze together the area between the plates,
causing compressional forces. These forces cause layers of rock to bend, buckle, and be pushed upwards.
If the force is great enough folded mountains result.
5.
Describe how tensional forces create mountains from a normal fault.
Tensional forces can create mountains from a normal fault by producing a “BLOCK MOUNTAIN”. This
occurs when two normal faults occur parallel to each other. The broken plate between the two faults was
forced upwards creating a mountain.
6.
Describe how compressional forces create mountains from reverse and overthrust faults.
Reverse Fault:
Overthrust Fault:
7.
Occurs when compressional forces caused the simple rock layers around a fault to push
against each other instead of pulling away. One block was forced upward creating a
reverse fault and a mountain.
Involves the faulting of previously folded layers of rock pushed up over other
layers.
Explain what causes a volcano to erupt.
Volcanoes erupt as a result of two of the earth’s tectonic plates coming into contact with each other. These
plate boundaries are intensely hot because of friction, pressure and the decay of radioactive materials.
Frequently, this intense heat melts rock beneath the crust, producing magma. As the magma heats up, it
expands and moves through cracks and fractures in the earth’s crust until it reaches the earth’s surface.
8.
Describe the characteristics of the following types of volcanic cones;
a)
Ash-and-cinder cone
b)
Shield cone
c)
Composite cone
Ash-&-Cinder Cone
Symmetrical
Steep sides/Large crater
Chiefly composed of ash and
cinders
Often quite explosive
8.
Characteristics of Volcanic Cones
Shield Cone
Composite Cone
Flat and broad
Periods of both quiet and
explosive activity
Chiefly lava flows, not eruptions
Mixed layers of lava, and ash and
cinders
Quiet, non-explosive
Shape somewhere between cinder
cone and shield cone.
How does the location of active volcanoes relate to places where plates meet?
Most active volcanoes are located in the mountain ranges on the margins of continents. Most mountain
ranges are formed on the edges of tectonic plates, where plates collide, slide past each other, or are pulled
apart, or where on plate is subducted below another. It is here that volcanic activity occurs because breaks
in the crust allow molten rock and gases to reach the surface.
9.
Distinguish between the ANTICLINE
and SYNCLINE of folded rock strata.
The diagram at the right shows the location of the
Anticline and the Syncline in folded rock.
10.
Are there global patterns in the location of landforms? If so, what are they?
Yes, there are a number of global patterns. For example:
i)
ii)
Mountain ranges tend to be located at the margins or edges of continents.
Some continents have similar landform configurations. This is the case with North and
South America, where the landforms that exist from east to west in each continent are
very similar!
Chapter Two:
Wearing Down Landforms: Rivers and Ice
Definitions to know:
Weathering
Delta
Arcuate delta
Digitate Delta
Erratics
Cirque
Estuarine delta
Alpine glaciation
Outwash plain
Terminal moraine
Drumlins
Arete
Erosion
Physical weathering
Chemical weathering
Lateral Moraine
Eskers
Hanging Valley
Describe the mechanical process by which physical weathering occurs.
Mechanical Processes Causing Physical Weathering
Action
Occurs when the water which has penetrated the joints and cracks,
freezes. Water expands by 9% when it freezes, and it has been
suggested that this expansion causes the rock to fracture.
Temperature Change
Occurs when sudden heating of rocks causes it to expand, while sudden
cooling causes the rock to contract. Combined they cause the rocks to
fracture.
Exfoliation
When coarse-grained rocks break along curved surfaces. They break
apart in rounded sheets like the layers of an onion as a result of the
expansion of the rock.
Plant Growth
Force created by the wedging effect of the roots of plats such as trees,
shrubs, flowers.
Burrowing Animals
They expand existing cracks and fractures in the rocks as they tunnel
through them.
Process
Frost Fracture
1.
Describe the main interactions that result in chemical weathering.
Interaction
In Solution
Hydrolysis
Oxidation
2.
Interactions Creating Chemical Weathering
Event/Result
The addition of carbon dioxide, sulphur, nitrous oxides and organic
acids transforms rainwater into a weak carbonic acid, when then reacts
with certain rock minerals to form a new, soluble compound. This new
compound detaches and carries off minerals, decomposing the rock.
Carbonic acid reacts with a kind of mineral called a silicate and forms a
new, soft clay mineral. The silicate’s potassium, sodium, and
magnesium ions are dissolved and carried away in solution. The soft
clay left behind ultimately decays into soil or mineral deposits.
Involves the reaction of metallic minerals in rocks to the oxygen in
water. The result of the reaction is a new mineral called an oxide.
(Example: Yellowish or reddish-brown stains seen on many rock
surfaces are common oxide of iron, while pale-greenish colours often
indicate an oxide of copper). Oxidation often creates softer minerals,
thereby weakening the rock.
What is the main difference between PHYSICAL WEATHERING and CHEMICAL
WEATHERING?
Forces in the physical environment, leading to the breakdown of rock into smaller pieces, without
changing the rocks chemical composition, cause physical weathering.
Chemical weathering results from the action of chemical elements or compounds that change the
rock’s chemical composition.
3.
In what climatic conditions is physical weathering accelerated?
Physical weathering is accelerated in regions that have a wet climate with a wide temperature
range.
4.
In what climatic conditions is chemical weathering accelerated?
Chemical weathering is accelerated in regions that have hot, wet conditions.
Describe the three stages in the life cycle of a river.
Stages in the River Life Cycle
River Cycle Stage
Characteristics
 Typically found in highland or mountainous
areas
 Have steep slopes
 Have relatively small volume of water and
rapid flow
 Tend to have narrow V-shaped valleys that are
relatively straight
 Rapids and waterfalls are also common
 Gentler slope
 Located in a flatter land surface
 Have many tributaries
 Braid, flat river valley & a well developed
floodplain
 Follows a gently meandering course over the
flood-plain
 Its erosion and deposition are nearly in
balance.
 It is moving the maximum amount of water in
a fairly efficient manner.
 Relief around the river is extremely flat
 River has almost NO slope
 River has very little momentum or speed.
 Has a very elaborate and meandering course
 Often have swampy area.
 Are very muddy
 Prone to flooding
 A wide flood-plain
 Have oxbow lakes where there once were
meanders.
Youthful
Mature
Old Age
5.
Describe the TWO ways that water erosion occurs.
i)
ii)
Water erodes VERTICALLY, that is, it erodes down to the bottom of a river channel.
Water erodes LATERALLY, that is, to the side of a river channel.
This erosion is caused by THREE processes:
I)
Hydraulic Pressure:
The pressure of the water on rock and loose material,
weathering it, removing it, and carrying it to new locations.
II)
Corrosion:
Water flowing over rocks containing substances such as limestone and
calcium carbonate dissolves minerals in solution. The effect of corrosion intensifies if
the water has become acidic.
III)
Abrasion:
Occurs when water carries rock fragments and particles and they bump,
scrape, grind, and gouge out other material, breaking them into smaller and smaller
pieces.
6.
Explain how deltas are formed.
Deltas form where they flow into some standing body of water such as a lake or the ocean because
this is here the greatest decrease in energy and velocity occurs in the river flow. At the lower
reaches of the river, there is usually no gradient (or slope) to supply energy to propel the water.
Consequently, the river will deposit much of the sediment that it picked up at higher elevations.
7.
Contrast the terms; ARCUATE DELTA, DIGITATE DELTA, and ESTUARINE DELTA.
Delta Type
Description

Curved, with a rounded seaward side.
Has the shape of a bow or a fan!
Digitate Delta

Has an irregular shape with finger-like
projections.
Estuarine Delta

A fill-in river channel at it mouth. The
tides of the ocean create tidal flats,
which are partially covered during high
tides.
Arcuate Delta
8.
What evidence can be used to determine the movement of a continental glacier?
At least two pieces of evidence can be used to determine the direction of movement of a glacier.
I)
II)
The location of a terminal moraine and the outwash plain marks the forward advance of a
continental glacier.
The examination of drumlins. The tail-like, thin, and tapered end points in the direction
the glacier moved.
9.
Identify each of the following continental glacial landforms: Terminal Moraine, esker,
drumlin, erratic, outwash plain.
10.
Identify the following features of Alpine Glaciers: Terminal Moraine, Lateral Moraine,
arête, cirque, hanging valley.
11.
Describe how fiords are formed.
Fiords formed as a result of Alpine Glaciation. The alpine glacier created glacial valleys that
reached down to the ocean. When the glacier melted, ocean water flooded into the valley, forming
a long, narrow, deep arm of the ocean extending inland
Chapter Three:
Wearing Down Landforms: Wind and Waves
Definitions;
Sea Cave
Sea Arch
Bay Beach
Stack
Spit
Bay Bar
1.
Describe how sea caves, sea arches and stacks are formed.
I)
Sea Caves: Wave refraction leads to erosion on a headland. Sea caves develop along lines of
weakness in the cliff such as a fault. A large hollow in the headland results.
Sea Arches: A feature along a coastline which results when two caves occurring on either side of
a headland are cut until they meet.
Stacks: Are formed when the roof of a sea arch collapses leaving an isolated pillar of rock
standing up from the sea bed close to the shore.
II)
III)
2.





Describe the processes involved in the “straightening out” of an irregular coastline.
The force of the waves is concentrated on the sides of the headlands.
Caves develop followed by sea arches.
The arches collapse, leaving sea stacks.
The sea stacks erode away, leaving a shortened headland.
The whole process then repeats further “straightening” out the shoreline.
Unit One
Case Study Objectives
1.
Examine how human activity adapts to landforms and water forms.
This objective relates to any way that humans have adapted to the landforms they live around.
The example given in your text is found on Page 27, which shows a topographical map of a river
valley in England. Humans have adapted to the landforms and water forms here in several ways.
For example, they have built the main highways so as to minimize the number of times it
intersects with the two major rivers in the region. These types of adaptation are true of almost all
landforms (i.e. Mountains, hills, plateaus, and plains) as well as water forms (i.e. rivers, lakes,
oceans etc)
2.



3.
Examine how humans respond to hazards posed by selected landforms and water forms.
There are a large number of different ways that humans respond to hazards posed by selected
landforms and water forms.
The case study on page 17 describes how humans respond to the threat of a volcanic eruption. They
respond in this case by monitoring the volcano before eruption and by getting most of the people to
evacuate the area.
The case study on page 29 describes the human response to The Red River Flood of 1997. In this case
humans response to the threat of this happening was the earlier construction of a Floodway around the
city of Winnipeg to take excess flood water away from the city. During the actual flood the people of
the region built the “Brunkild Dike”, which was a 40-KM long barrier of earth and sandbags.
The case study on page 45 “The Curonian Spit” responded to the threat of the erosion of a spit by
planting trees and shrubs on the spit and by building human-made sand dunes.
Develop a proposal for the economic use of selected landforms and water forms.
The idea here is to suggest ways that landforms and water forms can be used to create wealth
and/or employment. For example, the people of Clarenville decided to utilize the large hills
behind the community to build an alpine ski resort. Likewise, early settlers to the prairie region of
Canada discovered that the land was ideal for growing wheat and other grains. They subsequently
transformed the prairie grassland into farmland. These are just two of a large number of examples
of how landforms and water forms have been used to generate economic benefits.
4.
Justify a preference for the aesthetic appeal of selected landforms and water forms.
This is a personal question. Here you have to suggest possible reasons why you would like to live
or visit certain land or water forms. For example, some people want to live near a river because
they love the sound that the river makes, or love the beauty of a flowing river. Perhaps they enjoy
kayaking etc. There a any number of reasons why people like certain landforms more than others.
5.
Propose a solution to a threat posed by selected landforms and water forms.
Here you are being asked to suggest practical methods for solving threats posed by landforms or
water forms, for example;




The building of a Floodway around the city of Winnipeg to protect it from times when
the Red River floods.
The building of a large boulder breakwater along the beach in the small Newfoundland
town of The Beaches to protect the houses and the road from large waves that crash along
the beech during times of high winds.
Implementing and following strict building codes for the construction of houses and
buildings in places that experience earthquakes such as British Columbia, California, and
Japan.
ETC…….