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The Earth is not nearly as big as you might think...
Video...
We are only the tiniest drop in the ocean...
Lithosphere is the hard shell of the Earth, consisting of the crust and the topmost part of the upper mantle
Minerals are solid inorganic substances with clearly defined composition and properties
Minerals must be occur naturally in the Earth
Single Elements ◦ Gold (Au) ◦ Copper (Cu) ◦ Iron (Fe)
Several Elements Bonded Together ◦ Quatz (SiO2) ◦ Copper Sulphate (CuSO4)
There are about 4000 minerals on Earth ◦ They include Quartz, Diamonds, Rubies, etc.
Colour
Certain minerals have a characteristic colours due to an element in their composition ◦ They are known as idiochromatic minerals
Certain minerals are varying colours due to impurities in the minerals. Without the impurities, they would be colourless. ◦ They are known as allochromatic minerals
Transparency
Transparent ◦ Light passes right through them
Translucent ◦ Some light passes through but it’s not clear
Opaque ◦ No light passes through
Hardness depends on the strength of the bonds uniting the atoms in a mineral.
Is measured using the Mohs scale
The scale ranges from 1 to 10
The higher the number, the stronger the mineral
When you rub a mineral on a porcelain surface, it leaves a powdery coloured streak
The streak is not necessarily the same colour as the mineral, but will always be the same colour for that same mineral
Idiochromatic minerals leave a brightly coloured streak and allochromatic minerals leave a white or pale powder
Mining is the act of going and digging for a mineral once a source has been located.
The rocks which have been mined, that contain a mineral, are called ore.
When a particular area has a high amount of a mineral, the layer where it is found is called a deposit.
Rocks are heterogeneous solids composed of many minerals
Rocks are formed from 3 processes ◦ Pressure compresses sediment
◦ Rocks can be formed from volcanic activity
◦ The high pressure and heat causes rocks to transform
Igneous rocks ◦ Formed when lava cools
Sedimentary rocks ◦ Formed by the accumulation and compression of
debris
Metamorphic rocks ◦ Igneous and Sedimentary rocks transformed by heat
and pressure
Permafrost is ground whose temperature had been at 0°C or lower for at least 2 years
About 50% of the Canada is covered by permafrost
The frozen layer can attain a depth of 500m
It can be found in polar regions and at high altitudes
There are multiple sources of energy in the lithosphere.
These fuels are in different forms and used in many different ways.
These include fossil fuels, uranium and geothermics
Fossil fuels result from the transformation of organic residue
These energy sources consist of oil, natural gas and coal.
Oil and natural gas comes from small marine animals and algae that sank to the bottom of the seas a very long time ago.
When they died, these organisms sank to the bottom and were gradually covered in sand, rocks and minerals.
Under pressure, they are eventually turned into oil and gas.
Coal does not come from marine organisms, but from terrestrial plants and trees that once grew in swamps
Over time, these swamps are buried under sand and silt.
The organic residue was compressed and turned into coal.
When burning fossil fuels, they emit thermal energy (heat) which can be converted into electrical energy or mechanical energy.
Mechanical energy is used to make engines work.
The main by-products of a combustion are combustions are CO2.
Uranium is a radioactive element naturally occurring in the Earth’s crust.
It produces large amounts of nuclear energy.
A handful of uranium can produce as much energy as 70,000 kg of coal.
Uranium does not produce CO2, but does cause other problems.
The main problem with using radioactive energy is dealing with the radioactivity and the waste.
There is no way to eliminate radioactive waste.
The material and equipment which comes into contact with the radioactivity, it will stay radioactive for hundreds of years.
The waste is cooled and then either buried in former mines or in specialized concrete pits.
Geothermal energy is the energy that comes from the internal heat of the Earth.
Can be used for both heating and cooling of your home.
These reduce the CO2 emissions, however are much very costly to install than traditional heating methods.
The hydrosphere is the Earth’s outer layer of water, uniting water in all of its states: liquid, solid and gas
97.5% of water on the Earth is salt water
2.5% is fresh water
Of the fresh water, 79% is found in glaciers
21% is in lakes, rivers and groundwater
All the freshwater bodies found on continents, uniting rivers, lakes and groundwater falls to the earth as rain or snow , runs into streams, infiltrates the ground, seeps into natural cracks in rocks and minerals, flows into lakes and rivers, etc.
An area of land where all of its water drains into one larger body of water (lake or ocean)
The limits of a watershed defined by the following factors
Topography, geology, climate, vegetation, agricultural, industrial and urban development
Topography: The shape, slope and terrain of an area
Geology: The type, depth and structure of the rock.
Climate: Rain/snowfall, winds and temperature
Vegetation: The density and diversity of the plants in the area
Agricultural, industrial and urban development: Any human construction effects water flow
How many oceans are there? ◦ 5!
Pacific
Atlantic
Arctic
Indian
Southern (as of the year 2000)
Ocean water is moved by currents all around the world.
Two important factors must be discussed first
Temperature
Salinity
The depth of the ocean
Light can only penetrate to a certain depth
The ocean is divided into 3 zones ◦ Mixed layer
◦ Thermocline
◦ Deep Water
Mixed layer ◦ Up to ~200m in depth
◦ The warmest part of the ocean
Thermocline ◦ ~200 - ~1000m
◦ Water drops in temperature here due to the small amount of light which is present
Deep water ◦ ~1000m – Ocean floor
◦ Very cold (~3-5°C)
◦ Almost no light at all
At its deepest it is over 11 km down
The water pressure is around 15,750 psi
That’s equivalent to 15,750 pounds on every square inch of your body.
Atmospheric pressure is around 15 psi
Seasons
Temperatures can vary greatly from season to season
Due to water’s high specific heat capacity (ability to store heat), the temperature varies less than on land
Latitude
The closer to the equator, the higher the mean temperature
Equator between 25-28°C
Temperate Zones 12-17°C
Salinity is a measure of the amount of salt dissolved in a liquid
The average salinity is between 3.4 – 3.7%
The salt in the water comes from the dissolved minerals from rocks
Salinity drops near ice packs and glaciers due to their fresh water mixing with the salt water
Salinity increases to 4% in the Red Sea due to excessive evaporation
Dead sea ◦ 33.7%
Lake Assal ◦ 34.8%
Don Juan Pond ◦ Above 40%
◦ It’s so salty that even at -30°C, it doesn’t freeze
Ocean Currents is the movement of sea water in a certain direction
There are two main types of ocean currents, surface currents and subsurface currents
Ocean circulation is the combined effects of all the currents that move across the oceans
Surface Currents ◦ Mostly wind driven
◦ Move horizontally
◦ First 400m in depth
Subsurface Currents ◦ Not driven by wind
◦ Due to variations in densities
◦ Densities varies with temperature and salinity
Thermo = Heat
Halos = Salt
This is the movement of water in the ocean due to variations in the salt content and the temperature of the water
Bill Nye!
The cryosphere consists of all of the frozen water on the Earth
This includes glaciers, pack ice, frozen lakes and rivers, snow and, ice in permafrost
As it was previously mentioned, almost 80% of fresh water is found in glaciers
Pack ice is composed of the ice floating on the oceans near the North and South Poles
As pieces of ice break off, they float away and are then called ice floes
In the winter, the ice pack stretches over 12 million kilometres
However, due to global warming, the pack ice is shrinking every year
Glaciers are a mass of ice on land, formed by compressed snow
Icebergs are huge chunks of glaciers which break off and fall into the ocean
Due to ice being less dense than water, they float.
You don’t need to write this!
Glaciers cover about 10% of the Earth
During the last ice age, glaciers covered around 1/3 of the Earth
They are constantly in motion ◦ Anywhere from 2-3m a day to 20-30m a day
◦ Fastest recorded glacier movement was 67m in 25 minutes after an earthquake
They can be anywhere from the size of a football field to over 150 km long
Don’t need to write this!
About 90% of an iceberg’s mass is under the water.
There has been at least one recorded murder on an iceberg
The ice in an iceberg can be as much as 15,000 years old and take almost an entire year to melt