Download Chapter 6- The Lithosphere and the Hydrosphere

The Lithosphere & the
Hydrosphere
The Lithosphere
• Shell of the Earth - consists of the crust and
the upper mantle.
• Contains minerals and rocks.
Important Sections for the
Lithosphere
1.
2.
3.
4.
5.
Minerals
Rocks
Soil
Permafrost
Energy Sources from the Earth
1. Minerals
• Solid, inorganic substances with defined
composition and properties.
• Exist naturally.
• Made of identical shaped crystals.
Minerals are classified in 4 ways:
1. Colour
a) idiochromatic, (always the same colour, like
rubies).
b) allochromatic, (can take on different colours,
like quartz).
1. Minerals
1. Minerals
2. Transparency
• Minerals can be transparent, (clear),
translucent, (allow light to pass through), or
opaque, (light cannot pass through).
3. Hardness
• Hardness is evaluated using the Mohs Scale.
A mineral of a certain hardness can scratch
anything with a hardness that is lower.
1. Minerals
1. Minerals
4. Streak
• When rubbed on porcelain, minerals leave a
trace of powder. This is the streak.
• The colour left depends on the type of
mineral.
1. Mining of Minerals
• Minerals in their raw state is called ore. Ore
is extracted from the lithosphere, (rock
containing mineral), then separated from
the rock.
2. Rocks
• Rocks are heterogeneous solids composed
of many minerals. Unlike minerals,
composition of rocks is not clearly defined.
• Can be used for decoration, building,
insulation, etc.
• There are three types of rock:
1. Igneous
2. Sedimentary
3. Metamorphic
2. Igneous Rock
• Formed when magma cools and solidifies.
• There are two types: Intrusive and Extrusive.
2. Sedimentary Rock
• Formed by the accumulation and
compression of debris over many years.
• These rocks are formed at the Earth’s
surface or on the surface of the ocean floor
and show visible layers.
2. Metamorphic Rock
• These originate as either Igneous or
Sedimentary rocks that become
transformed by intense heat or pressure
over millions of years.
3. Soil
• Soil is formed from parent rock, a layer of
rock beneath the Earth’s surface.
• The parent rock breaks down over time, due
to frost, wind, rain, and the freeze-thaw
cycle and mixes with decomposing organic
matter to form soil.
• As soil develops, it forms distinct layers,
called horizons.
3. 5 Soil Horizons, (layers)
1.
2.
3.
4.
5.
Organic matter, (decomposing plants and
animals, called humus).
Topsoil, (humus and minerals, supports plant life).
Subsoil, (small mineral particles, trees get
nutrients here).
Fragmented parent rock, (chunks of rock formed
from layer below).
Unaltered parent rock, (starting point for soil
formation).
3. Fertility of Soil Depends on…
1. Presence of minerals, (nutrients for
vegetation).
2. Adequate moisture, (can hold onto
moisture).
3. Appropriate pH, (soil that is too acidic or
alkaline is not healthy for vegetation).
4. Permafrost
• In northern regions, large expanses of soil
are permanently frozen, even in Summer.
This type of ground is called permafrost.
• For ground to be classified as such, it needs
to be at a temperature of 0°C for at least two
years.
• Around 50% of Canadian soil is permafrost.
• Permafrost is not limited to polar regions,
but can be found in areas of high altitude,
like mountain peaks.
4. Permafrost
• In certain regions, the upper layer of
permafrost will thaw in the Summer. This is
called the active layer.
5. Sources of Energy in the
Lithosphere
1. Fossil Fuels
• Result from the transformation of organic
matter that accumulated millions of years
ago. Pressure caused the organic matter
to be transformed to fossil fuels.
• Coal, natural gas and oil are fossil fuels.
• Natural gas and oil result from marine
organisms.
–
Accumulate on the sea floor and become
covered in sand and silt.
5. Sources of Energy in the
Lithosphere
• Coal is formed from trees and other
terrestrial organisms that once grew in
swamps. Over time they were buried and
compressed.
• When fossil fuels are burned, they produce
CO2 and CH4.
5. Sources of Energy in the
Lithosphere
2. Uranium
• A radioactive element found naturally in the
Earth’s crust.
• Splitting its atom, (fission), allows a huge
output of energy, (one handful provides as
much energy as 70 tonnes of coal).
• Nuclear reactors needs to cool waste and
then bury it.
• Risk of accidents is a constant concern due
to the radioactivity.
5. Sources of Energy in the
Lithosphere
3. Geothermal Energy
• Uses the internal heat of the Earth by
sending a fluid deep underground to be
heated. The fluid returns to the surface, hot
enough to be converted to electrical energy.
• Used mostly in volcanic regions of the world,
where the crust is thinner. No fluid is
needed.
SECTION #2 - THE HYDROSPHERE
The Hydrosphere
• Outer layer of water on Earth, which
includes all states of water: liquid, solid and
gas.
Important Sections for the
Hydrosphere
1.
2.
3.
4.
Inland Waters & Watersheds
Oceans
The Cryosphere, (frozen water)
Energy from the Hydrosphere
1. Inland Waters and Watersheds
• Inland waters are fresh water, includes
lakes, rivers and groundwater.
• Watersheds are areas where inland waters
drain into the same larger body of water.
– Watersheds are sometimes called Catchment
Area.
• Water flow is influenced by topography,
geology, climate, vegetation, development.
• Quebec has two main watersheds.
2. Oceans
• There are five oceans: Pacific,
Atlantic, Indian, Arctic and
Southern, (Antarctic).
• Oceans temperatures are
determined by:
a) Depth: below 200m temperature
drops drastically, (called
thermocline zone – some
sunlight, but vert little).
b) Seasons
c) Latitude, (warmer around
equator).
2. Oceans
• Ocean circulation is caused by ocean
currents.
a) Surface currents are caused by wind, and
move horizontally.
b) Subsurface currents caused by density of the
water and salinity (colder and saltier=more
dense)
c) Thermohaline circulation is the combination of
both, (conveyor belt responsible for regulating
global climate). Ocean currents bring warm an
cold air with them.
2. Oceans
• All bodies of water have a certain salinity.
– Percentage of dissolved salts in a solution.
• Based on salinity, water can be classified.
Type of Water
Fresh Water
Ex - Lakes, rivers, streams, etc.
Brackish Water
Where fresh water meets saline water
Ex – Estuaries, certain seas
Saline Water
Oceans, seas, etc.
Brine
High concentrations of salt in solution.
Ex – Dead Sea, Great Salt Lake
Salinity
Less than 0.05%
0.05% - 3%
3% - 5%
More than 5%
3. The Cryosphere (Frozen Water)
• The cryosphere consists of
glaciers, pack ice, frozen
lakes and river, etc.
1. Pack Ice
•
•
Ice floating on the oceans
near the North and South
poles
Global warming has caused
Arctic ice pack to shrink
significantly
3. The Cryosphere (Frozen Water)
2. Glaciers
• Masses of ice on land.
• When chunks break off and fall into the sea they
create icebergs.
• This causes a rise in sea level, just like ice cubes
in your drink does.
• When ice melts, salinity is affected and water
becomes less dense. This could have an impact
on ocean currents and therefore global climate.
4. Energy Resources of the
Hydrosphere
• The movement of water, (usually rivers and
waterfalls), provides an immense source of
energy.
• Transforming it into electricity can be
challenging because it requires large
facilities.
• Hydraulic energy is derived from moving
water.
• Hydraulic energy is renewable, and no
greenhouse gases are emitted, but cause
severe damage to ecosystems.