Transcript Overview of ALL chapters

Overview of chapters
1-7
Chapter 1:
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The Earth is not a perfect sphere because it is wider around the
Equator compared to the Poles. However it LOOKS perfect in our
eyes!
The composition of the troposphere (lower layer of the atmosphere),
hydrosphere and crust can be found on p. 10 in the ESRTs.
Latitude lines run across the globe (like from E to W) but are measured
as North or South of the Equator. Longitudes run from Pole to Pole
(like N to S) but are measured as East or West of the Prime Meridian.
Ch. 1 continued…
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You can find North by looking for Polaris (the North Star) – it can be
found by lining up the “pointer stars” in the “cup” of the Big Dipper!
(See p. 17 in your review book.)
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Your latitude = the angle to Polaris if you are north of the Equator.
Every 15 degrees of Longitude change = 1 hour solar time difference.
Isolines connect points of equal value on a map. These can be
measurements of many different things, including temperatures,
elevations, air pressure, pollution levels, volcanic ash thickness…
Ch. 1…
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A profile can be drawn for a view across a map. You need a scrap of
paper for this! (See p. 24 in the review book.)
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Gradient – change in value/distance between 2 points. (See p. 1 in the
ESRTs.) If isolines are close, the gradient is steep.
Contour lines make a “v” to the UPHILL direction when they cross a
river!
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Ch. 2
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Minerals have well-defined physical and chemical
characteristics (due to their internal arrangement of atoms)
that help a person identify them. See p. 16 in the ESRTs.
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Rocks are made up of 1 or more minerals. The 3 different
rock categories are determined by the method by which they
formed.
Igneous rocks formed from the cooling and solidification of
molten magma or lava. The larger the crystal, the LONGER
the cooling time. Small crystals = quick cooling. Glassy
rocks = instant cooling – no crystals formed! Dark and
dense = mafic. Light and less dense = felsic. (Except for
black obsidian!) See p. 6 in the ESRTs!
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Ch. 2 continued…
• Sedimentary rocks form from sediments
piling up in water. Some sed. Rocks form
from the chemicals that are left behind when
water evaporates. Others form from organic
remains. See p. 7 in the ESRTs!
• Metamorphic rocks form when other types of
rocks get changed from heat and pressure.
Some of these rocks show “foliation” –
banding or mineral alignment. This happens
due to REGIONAL metamorphism. See p. 7
in ESRTs!
• Only sedimentary rocks can have fossils.
Ch. 3
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Earthquakes occur when there is movement along
a “fault.” The first movement occurs at the
“focus.” The point on the surface directly above
the focus is called the “epicenter.”
P-waves travel faster than S- waves. P-waves can
go through both solids AND liquids. S-waves only
go through SOLIDS. Both waves travel faster
through denser materials.
P. 11 in the ESRTs has a graph to find all sorts of
earthquake info:
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The distance to the epicenter can be found if you know
the time difference between the P and S-waves.
Also, you can find the distance if you know the travel time
for either the P or S-wave.
If you know the distance, you can figure out the time
difference between the P and S-waves.
Etc.
Ch 3…..
• 3 circles must be drawn showing the epicenter distance for 3
places before you can locate the epicenter. (See p. 58 in your
review book.)
• Seismic data helps tell us about the layers of the Earth that we
can’t see! There is a region of much higher density (the
“Moho”) between the crust and the mantle. The outer core is a
liquid. (See p. 10 in the ESRTs!)
• We can infer the composition, density, pressures and
temperatures of the layers of the Earth. (P. 10 in ESRTs)
Ch 3….
• Meteorites tell us that the inner and outer core are mostly
iron…and nickel!
• The crust is moving in all sorts of directions due to the
convection currents in the mantle. There are divergent,
convergent and transform boundaries! (you can see examples
on p. 5 AND 10 in the ESRTs)
• Earthquakes, mountains and volcanoes all tend to appear near
each other – near plate boundaries.
• Hot spots are regions where heat flows upward from the
mantle and causes volcanic activity on the surface. (P. 5 in the
ESRTs!)
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Ch. 4
Physical and chemical weathering break rock into
smaller pieces. Know some examples of each
type! (p. 81-82 in the review book)
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Chemical weathering happens faster in WARM, MOIST climates –
like Florida!
Soils form from the weathering of rock material PLUS the activity
and decay of biological material – like worms, plants, fungi and
insects…
Ch 4…..
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Weathered material may become small enough to be easily eroded.
Erosion happens via 4 methods: gravity, water, wind and glaciers
(GWWG.)
The erosional method that moved a rock will leave clues:
– Gravity == jagged, angular, unsorted, bottom of cliff.
– Water == rounded, smooth. Makes “V”shaped valleys.
– Wind == only moves the smallest particles – sand, silt and clay.
May be pitted or frosted…or have a strange triangular shape (a
“ventifact”)
– Glaciers == can move ANYTHING! Leaves striations – scratches –
grooves. May put large boulders (“erratics”) in odd places. Makes
“U”shaped valleys.
Ch. 4….
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Depositional clues can let you know what did the moving. Examples:
– Gravity = bottom of the cliff –mixed sizes (unsorted)
– Water = separated by size –largest settle first, as soon as the water
slows down. They may be “graded” – layered.
– Wind = only small particles – may form sand dunes that are shaped
by the wind. (gentle side = where the wind is hitting first, steep
slope = the other side of the dune)
– Glaciers = unsorted, unconsolidated sediments. May form low hills
(Drumlins) that have a steep end and a pointy end. The steep end
points “North” – which is the way the glaciers came from. The
pointy end points “South” – showing the way the glacier at moved.
Ch 4…..
• The landscape of an area is shaped by the methods
of erosion and deposition that are the most
prevalent. Also, the bedrock type influences the
shape of the landforms. See p. 2 and 3 in the ESRTs
for examples!
• Rivers will form special patterns depending on the
landforms.
Ch. 5:
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Scientists use the following concepts to help
determine the order of events that happened in the
past:
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Uniformitarianism (The events in the past happened at
the same rate and in similar ways that they happen today.)
Superposition (The oldest rocks in the layers are at the
bottom – as long as there has been no overturning,…etc.)
Original Horizontality (The rock layers were most likely
laid down horizontally, so if they look different now, they
were affected by something that came after them!)
Cross Cutting, Intrusions, Extrusions etc. (Rocks that are
AFFECTED BY another process are older than that
process. Look for signs of contact metamorphism (cm) to
see which came first.)
Ch. 5…
• Pages 8 and 9 in the ESRTs are invaluable!
• Pay attention to the index fossil names and
letters across the top of pgs. 8 and 9. Find
the exact times that these organisms lived.
• Index fossils are: W i d e s p r e a d
but lived only a short time.
Ch. 5…
• Absolute age can be determined by looking
at the ratio of certain radioactive elements
compared to their decay (daughter) product.
If there’s a 50:50 split, then 1 “half-life” has
passed. If there is a lot more decay product,
then more that one “half-life” has passed.
See p. 1 in the ESRTs for examples.
Ch. 6 and 7
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The structure of our atmosphere can be found on p. 14 in the ESRTs.
Air pressure is affected by altitude, temperature and humidity. These
3 things all have an “inverse” affect on the air pressure. When either
altitude, temperature or moisture levels go UP, the pressure goes
DOWN.
The charts on p. 12 in the ESRTs are VERY IMPORTANT! Remember
to subtract the wet-bulb temp from the dry-bulb temp before using the
charts.
When there is more moisture in the air, both the dewpoint AND the
relative humidity rise. When temp and dewpoint are getting closer,
the chance of precipitation increases.
Ch. 6 and 7….
• Wind is caused by differences in air pressure which can be
caused by differences in air temperature. Facts about the wind:
– Winds always blow from high pressure to low.
– Winds are named for where they came (from).
– When isobars are close, winds blow the most!
– The Coriolis Effect makes winds in the Northern Hemisphere
blow this way: Low = inward, counterclockwise High = out,
clockwise
Ch. 6 and 7…..
• Know your weather instruments!
• Clouds form when air RISES, EXPANDS and COOLS to
DEWPOINT. Water vapor condenses.
• You need condensation nuclei to make a cloud.
• LOW pressure leads to cloud formation (because air is rising!)
but HIGH pressure makes the skies clear! (because air is
sinking!)
Ch. 6 and 7…
• Most weather systems move across the U.S. from southwest
TO northeast.
• Most of the sun’s energy goes into the evaporation of water.
This energy is RELEASED when water condenses (like during
cloud formation!)
• Air Masses (different moisture and temperature characteristics)
determine an area’s weather. cP = dry, cold mT = moist,
warm… (see p. 13 in ESRTs)
Ch 6 and 7…
• Use p. 13 in the ESRTs to see the front symbols (they point in
the direction that the front line is moving!) and the synoptic
weather map station symbol.
• DOUBLE CHECK the synoptic weather station symbol!! No
units or labels are used. The temps are in Fahrenheit. The air
pressure is in millibars, but is shortened to only the LAST 3
DIGITS. When you convert back, you either put a “9” or a “10”
in front of these 3 numbers. Put a decimal between the last 2.