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Planet Earth
Section 1.1
Model of Earth
 Model
Definition: an idea of something that can’t be
fully known or seen. A way to picture an object
in its real form.
Example: Globe is a model of Earth
Geologists
Definition: scientists that study Earth, who use
models to understand the inner structure.
Three Major Layers of the Earth
•
Starting from the inner most layer to the outer most layer.
Inner Core: consists mainly of solid iron
and nickel, reaching temperatures of
7000 degrees Celsius
Outer Core: thought to be liquid due to
pressure not being great enough to turn
molten rock into solid
Crust: covers the surface of Earth.
The Earth’s Crust
Crust:
 All living things are found here
 Storehouse of minerals (ex. iron, copper ore)
 Fossil fuels (ex. Oil, natural gas, coal) **supply
energy needs
Note: What makes up the crust - - covered with
vegetation, fresh and saltwater areas, BUT
these only form a thick layer most of the crust
is made up of solid rock
Section 1.2 - Sudden Earth
Events
 What are some Examples????
- Earthquake
- Volcanic Eruption
- Typhoon
- Tsunami
- Tornado
- etc
Earthquakes – What are they and
what causes them?
Definition: tremblings/ vibrations in the
ground
Cause
- Sudden release of energy that has slowly
been building up within the Earth’s Crust.
** Pressure built up causes the rock to first
change in shape and then break
This is called “The First Break” or is known
as the “FOCUS”
These waves are called “SEISMIC
WAVES”- shaking that you will feel
comes from the seismic waves moving
through the ground.
Epicentre: point on the surface directly
above the focus
Measuring Strength of
Earthquakes
Various scales to determine the
strength /magnitude of an earthquake
Usually given a number on a
“RIChtER SCAlE”
Charles Richter – American
developed in 1935, starts at 0 for every
one increase means it is 10 times amount
of ground motion
Volcanoes
Activity (pg. 360)
1. Define the term VOLCANO
2. Draw, Color and Label (in your own
words) the 7 steps in Figure 1.10
Section 1.3 Incremental Changes: Wind, Water and Ice
Jigsaw Puzzle Activity
-- Get into groups of 4
-- Number each person 1, 2, 3, and 4
1s: will become experts about Weathering
2s: will become experts about Erosion
3s: will become experts about Deposition
4s: will become experts about Glaciers
-- please get into expert groups
-- fill in your booklets about your area of expertise
(15 minutes)
-- you will then come and enter the info on the smart
board
Weathering

Mechanical Weathering
This occurs when rock is broken apart by physical forces such as water and
wind.
- mechanical weathering ‘wears away’
- sedimentation ‘builds-up’

Chemical Weathering
- This occurs when water and oxygen react with the minerals in rocks to produce
new minerals.

Biological Weathering
- living things (plants, animals, bacteria and fungi ) can breakdown rock
- plant roots force their way into small spaces in rocks and soil. As the roots
grow they apply enormous amounts of pressure on their surroundings, breaking
apart rocks.
Erosion & The Effects of Moving Water
 Water is one of the most powerful causes of erosion. Sudden or
incremental changes occur due to the flowing of water - rivers,
rain, ocean waves. As rivers flow they carry a load of silt, sand,
mud and gravel called sediment.
 When a river becomes mature it begins to meander (curving its
bed from side to side). As it slows the sediment begins to fall to
the bottom.
 Sedimentation is the process of sediment being deposited,
usually at the bottom of oceans, lakes and rivers.
 Landforms created by flowing water are called Fluvial
landforms. The powerful forces of erosion caused by moving
water wear away rock and soil and transport them to other
locations.
Eroding Away
 Agents of erosion include: glaciers, gravity, wind, and
water. Changes can occur gradually (glaciers) or
rapidly (flash floods, landslides, rock slides).
 Erosion
causes
landslides
and
rock
slides
wind carries rock particles across the landscape,
eroding the land by wearing away soil. (planting
vegetation, contour farming and reduced tillage can
reduce the effects of wind erosion).
Glaciers
 Large rocks caught up in a glacier and then left behind when the glacier
recedes are called drumlins and moraines.
 Scratching and grinding, made in the bedrock, by glaciers carrying
rocks is called erosion.
 As the glacier melts (or, retreats) it leaves behind sediment in the form
of small hills, called drumlins and snake-like hills called eskers.
 Glacier: a moving mass of ice and snow.
 Bedrock: the layer of solid rock beneath the loose rock fragments.