GEOLOGY

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GEOLOGY
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Credit NASA
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Credit NASA
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Orion Nebulae
Where did the earth come from?
Credit Stardate.org
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Most societies have creation stories (myths)
You can read some here http//www.gly.uga.edu/rai
lsback/CS/CSIndex.html
Much of this course can be thought of as the
creation story as told by the science of our
civilisation.
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Once upon a time (13.7 billion years ago,
approx.) there was a small lump of tremendous
mass and temperature in the middle of
nothingness and then
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This is called the Big ____ Theory
http//www.astro.ucla.edu/wright/cosmology_faq.ht
ml
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Very rapidly, space-time comes into being and
expands, subatomic particles appear and form
_____, great clouds of matter roam the vast
universe.
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All stars form from clouds of gas and dust which
roam our universe. Eventually, gravity causes the
cloud to collapse since the cloud is _________,
material falls in along the "poles" faster than
it does near the "equator". This flattening
results in a disk-like object.
Material slowly wends its way into the center of
this disk, forming a new star. While the star
continues to grow, lumps form in the disk which
will ultimately become ________.
Credit NASA
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The disk eventually thins as more material falls
onto the star and the protoplanets. A hole in the
disk near the star forms as material is
completely incorporated into the star and planets.
Now fully formed planets exist within the hole,
even as new planets are still under construction
in the outer parts of the disk
Ultimately, the remaining dust clears completely,
leaving a fully formed _______________ like our
own.
Credit NASA
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See video at http//cougar.jpl.nasa.gov/HR4796/ani
m.html
Credit NASA
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How do we know this??? Did anyone ever SEE
this??? It sounds like somebodys dream animated
with lame special effects. Except that it comes
from scientists (albeit government scientists).
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So, what is science? Is it a thing, a person, a
process?
Our definition for now the accumulated ideas of
modern (our) civilization about how things work
what causes what, why it rains, why we get
sick, etc.
The Scientific Method a codification of the
process of applying _________________ to
answering questions about how things work.
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The scientific method is basically a repeating
_____ of observing, questioning, hypothesizing,
experimenting, observing, etc.
No one knows when this got started.
Or when it is going to end.
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For example, why cant you tickle yourself?
You notice that you cant tickle yourself
You wonder why you cant tickle yourself
Then, you think of an hypothesis, a ________
answer (reason why you cant tickle yourself).
Then, contrive an experiment to test your
hypothesis - predict a new observation and then
arrange things so you can make this new
observation.
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If the scientific method is a cycle, how does it
ever result in knowledge?
provisional answers
observe
question
experiment
hypothesize
Scientific knowledge is the accumulation of
provisional answers to questions, answers that
have _______ the process of repeated cycles of
the scientific method that have not been
___________. Well tested answers become ______.
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This is what I LOVE about science, and what
drives many people CRAZY.
Scientists are always qualifying statements,
equivocating, defining terms, and in general
avoiding whenever possible drawing any definitive
conclusions about anything that matters.
Why?
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I think it is because scientists are acutely
aware that
KNOWING ? ______
Our knowledge about the world tells us we
(humans) are sentient beings on the planet earth
that are collectively constructing knowledge.
That knowledge assumes there is a world out
there that we can know, part of which includes
that very knowledge and the brains (and books,
etc.) that generate and sustain that knowledge,
but is much more than that knowledge, that
transcends it.
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So I claim the scientific view assumes that the
real world is _________________________, and that
our knowledge is an attempt to create an
imitation (model) of it, and further that this
model (world view) is necessarily under
construction.
Moreover, based on long hard experience, it is
hard to avoid the (provisional) conclusion that
the real world is very complex, and that our
model of it is not only incomplete, it is
________, and wrong in fundamental ways, and
perhaps cant possibly be ______ (which doesnt
prevent it from being fairly powerful - from our
perspective).
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• With this view, it is understandable why
  scientists
• 1. ________ about almost everything when
  questioned, yet
• 2. Devote their lives to persisting in this
  _________ quest to perfect the model

Current scientific knowledge is a great human
achievement, similar to a great pyramid. It is
vast, integrated structure and a true collective
creation.
Giza, Egypt
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Tikal, Guatemala (Mayan)
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Scientific knowledge should be internally
consistent
For example, Biology study of life
Is built on and is a subset of
___________ the study of atomic/molecular
interactions
Is built on and is a subset of
_________ the study of the fundamental
components of reality
_________ in Biology should contradict anything
in Chemistry or Physics.
including Medicine and Agriculture
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Similarly, the earth sciences, like Geology, are
based on chemistry and physics and consistent
with them.
The same is true for all the disciplines that
focus on humans, like Psychology, Anthropology,
Sociology, Economics, Political Science, etc.
These fields are also consistent with and
increasingly tied directly to Biology, Chemistry
and Physics.
All are originally subsets of Philosophy the
search for a rational explanation of everything.
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In order to arrive at what you do not know You
must go by a way which is the way of
ignorance. -T.S. Eliot, East Coker
Some readers, I am afraid, will conclude from the
title that I intend to recommend ignorance or to
praise it. I intend to do neither.There are
kinds and degrees of ignorance that are
remediable, of course, and we have no excuse for
not learning all we can. But our ignorance
ultimately is irremediable some problems are
unsolvable and some questions unanswerable. The
extent of our knowledge will always be, at the
same time, the measure of the extent of our
ignorance.
Because ignorance is thus a part of our
creaturely definition, we need an appropriate
way a way of ignorance, which is the way of
neighborly love, kindness, caution, care,
appropriate scale, thrift, good work, right
livelihood. Creatures who have armed themselves
with the power of limitless destruction should
not be following any way laid out by their
limited knowledge and their unseemly pride in it.

The way of ignorance, therefore, is to be
careful, to know the limits and efficacy of our
knowledge. It is to be humble and to work on an
appropriate scale. -from the preface
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Now, back to our story.
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See video at http//cougar.jpl.nasa.gov/HR4796/ani
m.html
Credit NASA
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Atoms and molecules within the nebula combined to
form larger particles. The ___determined what
kinds of particles could exist. Close to the Sun,
solar heat vaporized ices and prevented ________
elements, like hydrogen and helium, from
condensing.
The inner zone was dominated by ____________,
which clumped together into ever-larger bodies,
called planetesimals, eventually forming
the______ inner planets Mercury, Venus, Earth,
Mars.
Credit Stardate.org NASA
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In the solar system's outer region, though, it
was chilly enough for ices to remain intact.
They, too, merged into planetesimals, which in
turn came together to form the cores of the giant
planets. _______ and _______ contain the largest
percentages of hydrogen and helium, while Uranus
and Neptune contain larger fractions of water,
ammonia, methane, and carbon monoxide.
So, we really are the __________________
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And yes, we are now seeing many of the stages
of this
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The point is, the process of solar system and
planet formation determined basic aspects of the
composition of the planet including the
abundance and distribution of ____________.
This sets both the _________ as well as ______ on
what can occur on earth, along with many other
factors.
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As the earth formed it congealed into layers,
with elements distributing into the different
layers
The hot inner ______ is surrounded by a semisolid
______ below a thin, solid outer _____ on the
surface
2-9/2-8
Note 1st number is text figure (9th)/second is
number is 8th edition
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As the earth enlarged during condensation, the
increasing mass resulted in increased _______,
raising the internal temperature (4000o C in core)
In this semi-liquid state, elements distributed
according to _______, heavier elements to the
core (Iron, Nickel), lighter elements to the
surface (Silicon, Magnesium, Aluminum) which
formed the outer crust.
Periodically, _________ from the interior
distributed core materials in layers on the
surface, so these elements also exist in the
crust today.
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Recall the elements are different kinds of
atoms each made up of 3 types of particles
protons (big, positive charge), neutrons (big, no
charge), and electrons (small, negative charge).
For charge balance, the number of protons and
__________ is equal. Weight of an atom, as
well as its identity, is due to the numbers of
protons and __________.
Interesting that all elements are made of the
same ingredients, but have very different
properties.
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Gases were released also during this
densification stage and further through the crust
through ________ venting, producing the
atmosphere.
The early atmosphere was probably high in
___________, hydrogen, carbon dioxide, carbon
monoxide, nitrogen, ammonia, methane and other
gases. No _________.
There were no oceans until the surface cooled
enough for water to stay in a liquid state.
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At this point (4 BYA), the surface of the world
was starting to look like a place we would
recognize today land, sea and sky.
And still a very dynamic place geologically
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The crust, the outer layer, is in two zones 1.
The ________ crust underlying the
continents 2. The _______ crust underlying the
oceans (71 of surface)
Lithosphere the crust plus the underlying solid
layer of the mantle.
Asthenosphere lower portion of mantle, melted
rock flows slowly
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Heat from the core causes the molten rock of the
asthenosphere to rise toward the surface. This
can create __________ flows below the
lithosphere __________ cells result when cooler
rock near the surface flows toward the center
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Movement in the asthenosphere induces movement in
the solid lithosphere, which is divided into huge
sections called ___________ plates (15). The
movement of the plates is slow (a few cm. per
year)
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This movement is the cause of continental drift,
the long term changes in the position of the
continents.
Where has Lexington been?
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http//www.calstatela.edu/faculty/acolvil/plates.h
tml
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Oceanic ridge at a divergent plate boundary
material from the mantle is added to the plates
This movement causes the plates to interact with
each other in 3 ways separate, collide, slide
past each other. These interactions cause
various geological features, including mountains,
ridges and trenches.
Trench and volcanic island at a convergent plate
boundary. One plate rides up and other is driven
down subduction.
Transform fault connecting two divergent plate
boundaries. Most are in oceanic plates
t
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Note the mid-oceanic spreading trenches and
multiple transform faults
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Convergence of plates is an important cause of
mountain building, as the continental plate
compresses and folds as it rides up over the
subducted plate. Also material scraped from the
overridden plate can accumulate. In addition,
volcanoes often occur in these zones. The
Himalayas and __________ mountain ranges were
formed in this way.
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Volcanoes occur where molten rock (magma) from
the earths interior emerges through an opening
in the lithosphere.
Ongoing volcanic activity contributes gases to
the atmosphere, elements to the lithosphere, and
islands and mountains to the landscape.
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Beautiful Dangerous
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And creative
The ________ islands are being formed by the
Pacific plate moving across a hot spot
volcanism in the middle of a plate (rare).
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Earthquakes are shock waves generated by the
sudden movement or slippage of plates at
boundaries and faults.
They can create strong vibrations in the crust
and have secondary effects on the land and water.
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Many of these faults are in the ocean, but some
are on land, including the New Madrid fault zone
that includes Western Kentucky
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Earthquakes under water can induce shock waves in
the water, called tsunamis, aka tidal waves.
Such an event occurred Dec. 26 2004 in the Indian
Ocean
They can move extremely fast, more than 500 mph,
and travel for miles inland from the coast.
Fake photo
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http//www.phuket-tourism.com/tsunami.htm
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The Rock Cycle
The Lithosphere is made of Rock the cooled
surface crust of the earth. It varies greatly
from place to place in the world and is a complex
mixture of elements and compounds, especially
minerals.
Minerals are naturally occurring compounds with a
_________ structure. More than 2000 have been
identified as distinct minerals. They can be very
beautiful and are the source of many of our
resources.
http//www.wilenskyminerals.com/MINERAL_PHOTOS.htm
l
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Rock is formed directly in the cooling of the
crust, but once formed, it is subject to the
dynamic forces already discussed, and also
weathering.
Weathering refers to the breaking down of rock
into small particles, which results from physical
and chemical forces such as ________, grinding,
flowing water, oxygen etc. Plants and __________
also contribute actively to weathering.
These smaller particles are then subject to being
washed or blown away, a process called erosion.
This process can wear down mountains, and also
build soil. The eroded particles can be
transported to a new location by gravity, wind or
water, and collect in areas of ___________.
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Devils Tower, WY
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Three rock types based on method of formation
igneous, sedimentary metamorphic.
1. Igneous rock is the original rock, and the
bulk of the earths crust, resulting from the
________ of magma. It is continually being
formed by upwelling of magma, creating granite,
lava, pumice, basalt, etc.
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2. Sedimentary rock is formed from deposition of
___________ particles, often underwater
(sediments). As these deposited layers get
buried, they can become fused to form distinctly
layered rock limestone, shale, sandstone
(common in Kentucky).
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3. Metamorphic rock, forms when rocks are buried
and experience ____ temperatures and pressures.
Limestone gt Marble Shale gt
Slate Sandstone gt Quartz
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Rock cycle all of these rock types are subject
to the dynamic action of plate tectonics,
volcanism, subduction, weathering, etc. As a
result, each type can be, and is transformed into
the other types, creating a cycle of
transformation of rock in the lithosphere (see
fig. 2-29).
Even rock is ultimately a dynamic process
2-29
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Mining
Mineral resources are dispersed throughout the
crust, some places richer than others. They must
be mined.
They are ____________
Large amounts of crust must be processed to
obtain relatively small amounts of mineral solid
waste and disturbance of the landscape
Often toxic chemicals are released (acids,
mercury, arsenic)
Copper mine (open pit)
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Coal mining shares many of these problems
A classic tradeoff
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Paradise John Prine When I was a child my
family would travel Down to Western Kentucky
where my parents were born And there's a
backwards old town that's often remembered So
many times that my memories are
worn. Chorus And daddy won't you take me
back to Muhlenberg County Down by the Green River
where Paradise lay Well, I'm sorry my son, but
you're too late in asking Mister Peabody's coal
train has hauled it away Well, sometimes we'd
travel right down the Green River To the
abandoned old prison down by Adrie Hill Where the
air smelled like snakes and we'd shoot with our
pistols But empty pop bottles was all we would
kill. Repeat Chorus
Then the coal company came with the world's
largest shovel And they tortured the timber and
stripped all the land Well, they dug for their
coal till the land was forsaken Then they wrote
it all down as the progress of man. Repeat
Chorus When I die let my ashes float down the
Green River Let my soul roll on up to the
Rochester dam I'll be halfway to Heaven with
Paradise waitin' Just five miles away from
wherever I am. Repeat Chorus
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End