Earth Science
Introduction
Ch 1
1
Earth Science is the name for the
group of sciences that deal with Earth
and its neighbors in space.
Earth Science includes 4 general areas:
• Geology- the study of the
Earth. Broken down into
two categories:
• Physical Geology- studying
the composition of the
Earth and the process that
shape it.
volcanology
mineralogy
hydrology
Historical Geology – studying the changes of
The Earth, both physical and biological changes
Earth’s Formation
Paleontology
Ice ages
Plate Tectonics
• Oceanography – comp.
& movements of
seawater, coastal
processes and seafloor
topography.
• Meteorology – study of
the atmosphere,
weather and climate.
Clouds in upper atmosphere
Violent weather
The Titanic on the Ocean floor
Astronomy – studying the universe
and the objects in it
Nebular hypothesis – the solar system evolved from
an enormous rotating cloud of dust and gases. The debris
collects into what is now our planets
The Earth forms from the pieces of debris leftover after the
Sun formed. As the Earth cooled denser elements sank towards the
center creating the very different layers of the Earth
Least dense
Less dense
Most dense
Layers of differing Composition, sorted
by Density
• Descriptions based on the
composition and density
of the layers:
• Crust – least dense, rocky
matter, lots of silica
rock.(high in aluminum & silicon)
• Mantle – thick shell of
dense, rocky matter(upper
mantle contains common olivine
and pyroxene, lower mantle the
rocks contain more magnesium &
iron)
• Core – the most dense,
consists mostly of metallic
iron and nickel
Layers of differing Physical properties
• based on physical
properties (solid or liquid)
• Lithosphere – all of the crust
and the uppermost Mantle. Rocks
are rigid
• Asthenosphere - high
temp.
make the rocks “plastic” and easily
deformed
• Mesosphere - high temp &
pressure make the rocks solid &
strong
• Outer Core – Liquid, melted
rock
• Inner Core - solid
Remember: which words to describe Earth’s layers?
• Describing the
composition of the
Earth –
• Use: Crust, Mantle,
Core
• Describing what the
layers of the Earth LOOK
like –
• Use: lithosphere,
asthenosphere,
mesosphere, outer core
and inner core.
Ch 1.2 - Earth’s Major Spheres
• Hydrosphere- all the
water above, on and in
the Earth
• 7
Water covers over 70% of the Earth. Of that 70%, 97% of it is found in the worlds
oceans. That leaves only 3% of fresh water to be shared by all living things that require
Fresh water!
Another comparison of the amt. of
water available to us.
• Atmosphere- the air
above us.
• Geosphere – the solid
Earth. Crust, Mantle,
Core
Biosphere – all living things on
The planet
Note: how thin this layer is, but
oh so important to us!
Ch 1.4 Earth As A System
• A system can be any
size group of interacting
parts that form a
complex whole.
• An interface is the
boundary where the
spheres overlap and
interact. This results in
very distinctive biomes.
• If the geosphere is
mostly sand how does it
effect the biosphere?
• Is the geosphere mostly
sand due to what
happens in the
atmosphere?
• What role does the
hydrosphere play in this
biome?
• How does the
hydrosphere in this
interface with the
geosphere?
• Does it effect what the
type of biosphere can
live on this shoreline?
• Energy is needed to power these spheres and
their interactions
Sources of energy-
• The Sun
• Earth’s interior
People and the Environment
• The action of humans produce changes in all of the
other parts of the Earth System.
19
• Environment refers to
everything that
surrounds and
influences an organism.
• Environmental Science
– studying the
relationships between
people and the natural
environment
Resources- anything we have found a use for becomes a resource
• The Earth Sciences deal not
only with the formation and
occurrence of vital
resources but also with
maintaining supplies and
the environmental impact
of our use of these
resources.
Soil & plants
• Miner
Water
Minerals
Energy
wildlife
Resource Example: ALGAE
• Renewable
Resources
• Nonrenewable
Resources
• Can be replenished over • Can NOT be replenished
in a relatively short
relatively short time
period of time.
spans
Environmental Problems
Human Induced vs. Natural disaster
•
•
•
•
•
Air & water pollution
Acid rain,
ozone depletion
Global warming
Destroying natural
habitat
• Earthquakes
• Volcanoes
• Tornados
• Floods
• Landslides
• Explain how these last two could
also be human induced
Chapter 1.3
Maps & Mapping
How we represent the Earth’s surface
1.3 How We Represent the Earth’s Surface
• We use a grid system
• Latitude – a north/south
measurement, measured
in degrees (0o The
Equator – 90o The Poles)
• The lines run east/west
but measure north/south
• Also known as: parallels
• Longitude – the vertical
lines running
north/south, but
measuring east/west
• Measured in degrees
from 0 longitude- called
Prime Meridian to 180o
known as The Int’l Date
Line.
• http://geographyworldo
nline.com/tutorial/pract
ice.html
Map Projections
• The most accurate way
to represent the Earth is
• A flat map can be used
a globe.
but since the Earth is
round, some portion
will always be out of
proportion.
It’s not very
convienent
The Mercator Projection
While it is easy to locate places due to the straight grid lines there
Is a lot of distortion at the poles. (note the size of Greenland)
The Robinson Projection
This is one of the most widely used maps. It shows accurate distances, and shapes
There is some distortion around the edges. The longitude lines are curved to reduce
The area distortion at the Poles.
Conic Map Projection
Made by wrapping a cone of paper around a globe at a particular latitude.
There is almost no distortion along the line of latitude but much distortion in
areas away from this latitude. Best for depicting small areas.
Interrupted Map Projections
Placing the worst distortion over open ocean areas. Land areas
Are depicted fairly accurately. Can be difficult to read.
The Peters Map Projection
Straight grid lines allow for easy reading, shapes
Of continents are recognizable, most accurate when
Comparing actual land area.
Compare to Mercator shown
above
Topographic Maps- show elevation by means of:
Contour lines: a line on a map connecting areas of equal elevation
What type of relief is shown?
Compare the relief
Of this map to the
Previous one
Topo maps show more than just
Contour lines