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Bech: Geology
• 1. Explain how your life would be different if geology-the study
of earth-did not exist. What products and resources in our
everyday lives are Earth-based (they come from below ground)
• Rivers, lakes, and other
bodies of water
• WHY: Civilization has
always need water for
their bodies, farming,
and animals. Water is
needed for survival.
• 4.5 billion years old
(plus or minus about 1%)
• Scientists know this
through studying the earth
• Like people, the
earth shows age.
(Rocks, and
other land forms)
1. Heat in the form of volcanoes, geysers, and hotsprings shows
us that the interior of the earth is hot.
2. 2. Types of volcanic rock found and examined by geologists
3. 3. Shifting of the plates and rifts that allow for escaping of
heat.
4. Minerals found in the Earth’s crust
• Crust
• Mantle
• Outer Core
• Inner Core
• Pressure affects temperature.
• The weight of overlying
layers causes pressure and
temperature to increase
as you go deeper into
the Earth.
• Different substances
require different amounts
of pressure or temperature
to change states because
of the strengths of their
molecular bonds.
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Crust- solid Lithosphere-solid
Asthenosphere- solid, but plastic
Mantle- solid
Outer core- liquid
Inner Core- solid
• Liquid and solid layers in the earth have to do with what they
are made out of, heat, pressure.
• Evidence:
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Mountains
Types of Soil
Fossils
Plants
Animals
Rocks
Shore lines
Pangea is the theory of the
“supercontinent” The theory
is that all the continents were
together at one point, then
drifted and broke away
from each other.
• Plate tectonics is the theory
that the earth's lithosphere
(outer rigid shell) is composed
of several dozen "plates", or
pieces, that float on a ductile
mantle, like slabs of ice on a
pond.
• A hot spot occurs because
of the intense heat of the
outer core.
• This heat radiates through
the mantle bringing hot
solid rock upward to the
hot spot.
• Because of lower pressure
in the upper region of the
mantle the rock begins to
melt. This forms magma
which rises inch by inch
until it reaches the surface
forming a volcano.
-When two plates collide and one subducts below the other there is usually a small space
that magma can squeeze through, thus creating a volcano
-EX: Mount St. Helens and Mount Fuji
• Form: Mountains are formed by uplifting of the crust along fault
lines/zones
• Where: Western USA the Sierra Nevada, White mountains and
Rockies
• Shield Volcano
• form from "gentle" or nonexplosive eruptions of flowing lava.
• The lava spreads out and builds up volcanoes with broad, gently sloping
sides.
• Cinder Cone Volcano
• build from lava that is blown violently into the air
and breaks into fragments.
• smallest volcanoes and are cone-shaped
• Composite volcano
• largest and form symmetrical cones with steep sides.
• develop from repeated explosive and nonexplosive
eruptions of tephra
• Earthquakes and volcanic
activity are common in
the area, which is part
of the "Ring of Fire"
where the Pacific plate
of the earth's crust meets
other continental plates.
• Sunset Crater Volcano National Monument - Flagstaff
• Sunset Crater Volcano was born in a series of eruptions
sometime between 1040 and 1100. Powerful explosions
profoundly affected the lives of local people and forever
changed the landscape and ecology of the area. Lava flows
and cinders still look as fresh and rugged as the day they
formed. But among dramatic geologic features, you'll find trees,
wildflowers, and signs of wildlife – life returns.
• Caused by a sudden slip on a fault.
• Shaking of the ground caused by the sudden breaking and
movement of large sections (tectonic plates)
• Where are earthquakes common?
• Earthquakes are not randomly distributed around the earth. They occur most frequently
along plate boundaries. Very large, deep earthquakes occur at convergent boundaries
where ocean plates move beneath other plates, at regions called subduction zones.
• There are several reasons for the perception that the number of earthquakes, in general,
and particularly destructive earthquakes is increasing.
1) A partial explanation may lie in the fact that in the last twenty years, we have
definitely had an increase in the number of earthquakes we have been able to locate
each year. This is because of the tremendous increase in the number of seismograph
stations in the world and the many improvements in global communications.
In 1931, there were about 350 stations operating in the world; today, there are more that
4,000 stations and the data now comes in rapidly from these stations by telex, computer
and satellite. This increase in the number of stations and the more timely receipt of data
has allowed us and other seismological centers to locate many small earthquakes which
were undetected in earlier years, and we are able to locate earthquakes more rapidly.
The NEIC now locates about 12,000 to 14,000 earthquakes each year or
approximately 50 per day.
• the surface where
when two blocks of
the earth suddenly
slip past one
another
Epicenter
Focus
• The location on the surface of
the earth directly above the
hypocenter
• Point of which the wave
originates
• These foci of natural
earthquakes are found at
different depths below the
ground surface.
• There are three levels, Shallow,
Intermediate, and Deep.
• Earthquakes produce two main types of waves - the P-wave (a
compressional wave), and the S-wave (a shear wave). The Swave is slower but larger than the P-wave and does most of the
damage. Scientists have used knowledge of the differences
between these and other seismic waves to learn a great deal
about the interior of the earth.
• We name earthquakes after map locations near epicenters to
have a convenient way to refer to them, but this can be
misleading. We define the epicenter of an earthquake with the
latitude and longitude of a point, but the earthquake is bigger
than that point.
• The Mercalli intensity scale is a seismic scale used for measuring the
intensity of an earthquake. It measures the effects of an earthquake,
and is distinct from the moment magnitude Mw usually reported for an
earthquake (sometimes described as the obsolete Richter magnitude),
which is a measure of the energy released. The intensity of an
earthquake is not totally determined by its magnitude.
• The scale quantifies the effects of an earthquake on the Earth's
surface, humans, objects of nature, and man-made structures on a
scale from I (not felt) to XII (total destruction).[1][2] Values depend
upon the distance to the earthquake, with the highest intensities being
around the epicentral area. Data gathered from people who have
experienced the quake are used to determine an intensity value for
their location. The Mercalli (Intensity) scale originated with the
widely-used simple ten-degree Rossi-Forel scale, which was revised
by Italian vulcanologist Giuseppe Mercalli in 1884 and 1906.
• When the ocean floor is disturbed, it creates a huge wave that
is know as a Tsunamis.
• A Japanese word which
means “Harbor wave”
• Triggered by:
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Land slides
Earthquakes
Volcanoes
Asteroids
• Shaking of the ground can cause gas pipes to burst and electric
lines to fall down.
• EX: Lit candle falling over as the ground moves or something
flammable falling over.
• Fires can also occur afterwards
by way of Earthquake
aftershocks, as these too can
cause significant movement in
the ground
• Radon ( /ˈreɪdɒn/ RAY-don) is a
chemical element with symbol Rn
and atomic number 86. It is a
radioactive, colorless, odorless,
tasteless noble gas, occurring
naturally as the decay product of
uranium or thorium. Its most stable
isotope, 222Rn, has a half-life of
3.8 days. Radon is one of the
densest substances that remains a
gas under normal conditions and is
considered a health hazard due to
its radioactivity. Intense
radioactivity also hindered
chemical studies of radon and only
a few compounds are known.
• Why:Radon is responsible for the
majority of the public exposure to
ionizing radiation. It is often the
single largest contributor to an
individual's background radiation
dose, and is the most variable from
location to location. Radon gas
from natural sources can
accumulate in buildings, especially
in confined areas such as attics and
basements. It can also be found in
some spring waters and hot
springs.[3]
• The first step is to test your home for radon, and have it fixed if it is
at or above EPA's Action Level of 4 picocuries per liter. You may want
to take action if the levels are in the range of 2-4 picocuries per liter.
Generally, levels can be brought below 2 pCi/l fairly simply.
• The best method for reducing radon in your home will depend on how
radon enters your home and the design of your home. For example,
sealing cracks in floors and walls may help to reduce radon, but is not
sufficient. There are also systems that remove radon from the crawl
space or from beneath the concrete floor or basement slab that are
effective at keeping radon from entering your home. These systems
are simple and don't require major changes to your home. Other
methods may be necessary.
• People who have private wells should test their well water to ensure
that radon levels meet EPA's proposed standard.
• Layers of snow build up
and slide down the
mountain
• Certain weather conditions
like wind and rain
• A rock or a piece of ice
can shake the snow to slide
down the mountain
• Water under the snow
could make the snow slide
• The water table is the surface where the water pressure head is
equal to the atmospheric pressure (where gauge pressure = 0).
It may be conveniently visualized as the 'surface' of the
subsurface materials that are saturated with groundwater in a
given vicinity
• There are multiple threats to the quality of the nation’s
groundwater including: septic systems, nitrates, acid mine
drainage, pesticides, and waste disposal. In many counties, one
of the biggest contributors to groundwater pollution is leaking
underground storage tanks (UST's).
What is it?
• crude oil is a fossil fuel
• classified as a fossil fuel
• non-renewable energy
source
How is it formed?
• when sea plants and animals
die, and the remains become
buried under several
thousand feet of silt, sand or
mud.
• formed by hydrocarbons
• Soil is important for plants because it holds roots that provide
support for plants and stores nutrients.
• Plant-eating animals, including humans, would starve. Life as we
know it would cease to exist.
1 Mechanical weathering
Thermal stress
Frost weathering
Pressure release
Hydraulic action
Salt-crystal growth
Biological weathering
Chemical weathering
• Dissolution / Carbonation
• Hydrolysis on silicates and
carbonates
• Oxidation
• Biological weathering
• One of the main components that make up good vs. bad soil is
its p
• Garden soil will benefit from additives,
• you find earth worms in it
• breaks apart easy when you make a fist with some,but holds
until you do
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Hot springs
spring characterized by a
discharge of water ejected
turbulently and accompanied
by a vapor phase
exist in only a few places on
Earth
Jet-like eruptions
Near by volcanoes
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Geysers
any geothermal spring
a spring with water
temperatures above its
surroundings
People have been seriously
burned and even killed by
accidentally or intentionally
entering these springs.
Near by volcanoes
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Asia
Africa
North America
South America
Antarctica
Europe
Australia
• Avalanches
• Earthquakes
• Volcanic eruptions
• 2.1 Floods
• 2.2 Limnic eruptions
• 2.3 Tsunamis
• 3.6 Tornadoes
• World's First National Park
• 2,219,789 acres (Larger than Rhode Island and Delaware
combined)
• largest (132 sq. mi.) high altitude (7,732') lake in north
america.
• located in 3 states—
Wyoming, Montana,
and Idaho
(LAST QUESTION)
• Little pieces of our earth have been eroded/broken down
and worn away by wind and water.
• little bits of our earth are washed downstream where they
settle to the bottom of the rivers, lakes, and oceans
• layers are pressed down more and more through time, until
the bottom layers slowly turn into rock.
• Called fire rocks and are formed
either underground or above
ground
• formed when the melted rock,
called magma, deep within the
earth becomes trapped in small
pockets
• form deep in the earth where high temperature, great
pressure, and chemical reactions cause one type of rock to
change into another type of rock
• Metamorphic rocks begin to form at 12-16 kilometers
beneath the earth's surface