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Earth Science Classes

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Title: Earth Science Classes


1
Earth Science Classes
  • Course Requirements, Syllabus, and Review Topics
    by unit

2
Contact Information
  • I can be reached by calling the school (718)
    463-3111
  • My email is TeachPhysics_at_aol.com
  • My website address is www.TeachPhysics.com
  • My webpage on the school website is
    www.QueensAcademyHS.com

3
Classroom Rules
  • Be on time for class that means in your seat
    when the bell rings
  • Be prepared for class with writing materials
    pen and paper
  • No hats or do-rags in class
  • No electronics in class including cell phones
  • Be respectful of others
  • Absolutely no food in class

4
What is needed for this class?
  • A pen or pencil and a notebook everyday.
  • A copy of the Earth Science reference tables
    (supplied)
  • These are available in languages besides English
    just ask
  • A binder to hold handouts, class work and home
    works.
  • You will also need an inexpensive calculator
    capable of basic arithmetic for homework
    assignments.

5
Grades in Earth Science
  • 35 Exams, quizzes,
  • mid-terms and finals
  • 25 Class participation
  • 25 Homework
  • 15 Laboratory Activities

6
Grading policies
  • Rubrics show student performance levels.
  • To inform students of the expectations I have for
    them, and to make grading more objective, I use
    rubrics extensively in determining grades. This
    lets students see precisely what areas of a task
    they were successful on, and which areas need
    improvement. Rubrics are passed out to students
    before assignments so they know what is expected
    of them when they are given the task.

7
Tests are worth 35
  • These include quizzes, open book and take-home
    tests, and full-period exams, including the
    mid-term and final. Generally, to keep the values
    of these assessments proportional to their length
    and importance, I make each question worth 1
    point. In this way a short quiz with 10 questions
    is worth half as much as a test with 20
    questions. Full-period exams have some questions
    that require a more lengthy answer than a
    multiple-choice question and may have be worth
    two or three points while the entire exam is
    worth 40-50 points. To increase the significance
    of the mid-term and final, these are worth 100
    points each. Make-up tests are worth only partial
    credit unless the student presented a valid
    excuse for the absence. Make-up tests are worth
    65 of the original test value.

8
Full-Period exams
  • A full-period test is administered every 3 weeks.
  • Tests are almost exclusively on Thursdays.
  • Tests are returned the next day and we will go
    over the exam during class.

9
Homework - 25 of your grade.
  • Homework values are calculated in a similar
    manner as tests with each question being worth
    one point. In this way, more lengthy assignments
    have a higher value. In some cases there are
    questions worth more than one point because they
    involve a more lengthy answer, multiple parts, or
    a mathematical calculation.

10
Class participation is 25
  • This grade comes from attendance, class work, and
    participation in discussions. An attendance
    credit is given to each student. Students receive
    three points for coming to class on-time each
    day. This is reduced to one point if they enter
    the classroom after the bell rings, and zero
    points if they come in more than 20 minutes late.
    Students who present a valid excuse for their
    absence receive the three points for the day.
    Class work consists of reading and writing, and
    answering questions from the text, review book
    and worksheets. These are worth one point per
    question. Students who actively participate in
    class discussions are given additional points.

11
Laboratory exercises- 15
  • Lab exercises are graded on a pass-fail basis and
    are worth either ten points or zero points.
    Incomplete labs are worth 0 labs must be
    complete to earn credit. Make-up labs are worth
    only partial credit. If the missing lab is made
    up during the marking period in which we
    performed it, the value is eight points. In the
    following marking period it is worth seven
    points, afterwards, only six points. Students
    have to achieve a lab average of 65 and complete
    no less than 600 minutes of hands-on laboratory
    exercises to pass lab.

12
What is Earth Science?
  • Astronomy
  • During this portion of the course, we will learn
    about our solar system, the Milky Way galaxy,
    stars, planets, moons, comets and asteroids. We
    will also talk about the beginning of the
    universe, an event referred to as the big bang.
    We will discuss methods of determining where we
    are in the universe using a coordinate system.
    This section also includes how and why the Earth
    rotates on its axis, revolves around the sun in
    its orbit, and the causes for the seasons.

13
Energy
  • The study of energy will include electromagnetic,
    potential, kinetic, and thermal energy. We will
    learn the difference between temperature and heat
    energy, and how energy is transferred and
    transformed. We will also discuss changes of
    state for matter, and how energy is involved.
  • The Earths 2 sources of energy- internal and
    external will be discussed.

14
Meteorology
  • Meteorology includes factors that are related to
    weather and climate. Some of these include
    temperature, moisture, pressure, wind and
    precipitation. We will discuss weather patterns
    and their causes, global warming, and long term
    weather patterns known as climate. We will learn
    how meteorologists are able to predict and
    forecast the weather. This section also includes
    the water cycle.

15
Geology
  • Geology covers the different types of
    rocks-minerals, sedimentary, igneous and
    metamorphic. Geology explains the processes that
    create and wear down rocks. This section of the
    course will also cover earthquakes, tsunamis,
    volcanoes and plate tectonics. We will learn some
    of the characteristics of rocks and minerals, and
    identification techniques. The last section of
    geology deals with ways of determining the age of
    the Earth using fossils, radioactive isotopes,
    and a brief examination of the Earth's 4.6
    billion year history.

16
Reviewing Earth science
  • To help students review for classroom tests and
    the Regents exams, I pass out a review sheet
    during each of the 14 units of study.
  • Vocabulary and concepts are presented.
  • The following slides contain a copy of these
    review sheets.

17
Topic 1- Introduction to Earth's Changing
Environment
  • Universe-All matter, time, energy and space that
    exists.
  • Observation-The perception of some aspect of the
    environment made with one or more of the human
    senses-sight, hearing, touch, taste, or smell
  • Instrument- A human-made device that extends the
    human senses beyond their normal limits.
    instruments increase the range of observations
    e.g. microscope, telescope, and quantify (give a
    quantity to) an observation. Example it is not a
    small amount of water, it is 37ml of water.
  • Inference- An inference is an interpretation of
    an observation. A mental process that proposes
    causes, conclusions or explanations for what has
    been observed. An inference cannot be tested. It
    is based on our observation and also our past
    experiences.
  • Prediction- A type of inference about the
    conditions and behavior of the environment in the
    future. Predictions can be tested even though
    they may not be they must have the ability to
    be tested to be a prediction
  • Classification- A group of similar observations
    and inferences, a taxonomy. Example- Birds
    flightless birds flightless, aquatic birds-
    from general to specific.

18
  • Measurement- A means of expressing an observation
    with greater accuracy or precision. Measurements
    include units. Basic units in the SI system
    include the meter for length, the kilogram for
    mass, and the second for time.
  • Accuracy- How close a measurement comes to a true
    or accepted value. Example You measure the
    force of gravity to be 9.6 m/s2, since the
    accepted value is 9.806, your percent deviation
    is only 2. You are 98 accurate.
  • Precision-The ability to repeat a measurement and
    obtain nearly the same results each time. This
    may depend on the calibration of the measuring
    instruments. Example You measure the force of
    gravity 3 times and get 8.9, 9.4 and 10.6 m/s2.
    These readings are not precise-none are close to
    each other. Another time you take 3 measurements
    and get 9.2, 9.1, and 9.3. These readings are
    not accurate, but they are precise. Lastly, you
    make 3 measurements and get 9.6, 9.8, and 9.7.
    These readings are both accurate and precise.
  • Mass- The amount of matter in an object, the
    number and size of its atoms. The more atoms and
    the larger the atoms, the more mass. Mass does
    not vary by location as weight does. Example A
    student has a mass of 65kg. That is the mass of
    the student on Earth or the moon. The weight of
    the student on the moon would be 1/6 his/her
    weight on earth. Weight is the effect of gravity
    on a given mass.
  • Volume- The amount of space that an object
    occupies is its volume. rectangular objects we
    multiply length, width and height. Irregular
    shaped objects we use the water displacement
    method with a graduated cylinder.

19
  • Percent deviation- No measurement is perfect,
    they contain some error. Percent deviation is
    the difference from the accepted value divided by
    the accepted value multiplied by 100. Example
    You measure the mass of an object with an
    accepted mass of 125gm, but you get 127.5gm. The
    percent deviation. is (127.5gm-125gm) / 125gm
    100 2.5gm/125gm1002 Find the formula on
    the front cover of the reference tables.
  • Density- The concentration of matter in an object
    and the ratio of the objects mass to its volume.
    High mass with low volume equals high density.
    Low mass or high volume equals low density.
    Mass/ volume density units are kg/cubic meters.
    Formula on the ESRT
  • Density is constant for objects made of a uniform
    material no matter what size piece you have.
    density is how things will sort themselves out
    always with the most dense object on the bottom
    and the least dense on top. Density is
    responsible for layering and motion.
  • Rate of change- How much a measurable aspect
    changes over time is the rate of change.
    Example It is 60 degrees out when you wake up.
    Two hours later, it is 70 degrees. The rate of
    change is 70degrees-60 degrees) / 2 hours or 5
    degrees per hour. Formula on the ESRT
  • Cyclic change- Changes that occur with a regular
    or predictable cycle. Ex. tides, night and day,
    the seasons, full moons, and many more.
  • Natural hazard- A non-human situation that may
    threaten life. Ex Asteroids, blizzards,
    earthquakes, floods, tsunamis, hurricanes,
    thunderstorms, tornados, and volcanoes.
  • Interface- A boundary between 2 regions with
    different properties. Example At the beach where
    the shore meets the water is the land-water
    interface.
  • Dynamic equilibrium- The balancing of opposing
    forces. Example The level of Lake Erie remains
    nearly constant, it is in dynamic equilibrium
    because the water that flows out into the Niagara
    River is replaced by water that flows into it
    from the Detroit River.

20
  • Natural resources-Materials and energy sources
    found in the environment. Many natural resources
    especially fossil fuels (coal, oil and gas) are
    considered non-renewable. They will renew
    themselves, it just takes hundreds of millions of
    years!
  • Pollution- A concentration of any substance or
    energy that adversely affects humans and the
    environment. Example An electric plant
    discharges water that it uses for cooling. The
    increased temperature of the water around the
    plant kills fish and plant life around the plant.
  • Amount of error The difference between your
    measurement and the accepted value, always a
    positive number (absolute value), contains units.
    Example I measure 78 cm but the actual length is
    80 cm. the amount of error is 2 cm.
  • Scientific notation a way of expressing numbers
    without writing a lot of zeros. the zeros are
    replaced with a times 10 to some power, the power
    is how many zeros were replaced. Example 78,000
    7.8 x 104 In scientific notation, only a single
    digit is ever written on the left side of the
    decimal place.
  • Average or mean a number which is between the
    highest and lowest number in a list. Found by
    adding up the numbers in the list and dividing by
    how many numbers are in the list.
  • Graphing- dependent variable, the thing that
    changes as the experiment progresses always goes
    on the y-axis. Independent variable, always on
    the x-axis. Graphs include ALL of the following
    a title, a label on each axis including units
    (Note the units are not the label), a layout
    that is linear and uses 90 of the graph paper
    (not bunched up in a corner or running off the
    paper), a line-of-best-fit that shows the trend
    of the data (not necessarily a connect the dots
    line)

21
Topic 2-Measuring Earth
  • Atmosphere- The layer of gasses that surrounds
    Earth above the oceans and land. Contains for
    sub-layers. from the ground going up
    troposphere, stratosphere, mesosphere, and
    thermosphere. The ozone layer is in the
    stratosphere and protects life on Earth from
    harmful UV radiation. As altitude increases in
    the atmosphere, temperature both increases and
    decreases as various layers either absorb
    radiation or do not absorb radiation. Most of the
    atmosphere (78) is composed of nitrogen gas, not
    oxygen.
  • Coordinate system- A system for determining the
    coordinates of a point. Maps use latitude and
    longitude to accomplish this.
  • Contour lines- These are isolines that connect
    points of equal elevation.
  • Contour interval the vertical distance between
    contour lines on a topographic map.
  • Crust- The upper portion or top layer of the
    lithosphere.
  • Degrees parts of a circle. a complete circle
    has 360 degrees. Degrees are broken into 60
    smaller parts called minutes and minutes each
    contain 60 equal parts called seconds. Thus a
    latitude or longitude may be written as 45 31
    58 indicating 45 degrees, 31 minutes, 58
    seconds.
  • Earths interior- Everything between Earths
    crust and the center of the earth. From the
    center of the Earth to the crust these layers
    are inner core, outer core, stiffer mantle,
    asthenosphere( plastic mantle), lithosphere and
    crust.

22
  • Elevation- The vertical distance or height above
    sea level. This is shown with different colors on
    a relief map and with contour lines on a
    topographic map.
  • Equator- The halfway point between the north and
    south poles. The reference point for measuring
    latitude has a latitude of 0
  • Field- Any region of space that has some
    measurable value of a given quantity at every
    point. Example Magnetic or gravitational
    fields.
  • Gradient- The rate of change from place to place
    within a field. The closer the isolines the
    higher the gradient, the faster or the steeper
    the change. Examples Close isobars indicate
    strong changes in pressure, thus windy
    conditions close contour lines indicate dramatic
    changes in elevation, thus steep terrain.
  • Hydrosphere- The layer of liquid water between
    the atmosphere and the Earths interior. Most of
    the hydrosphere (66) is composed of hydrogen,
    hence the name.
  • Isolines- Lines that connect equal points of
    field values. Examples Isotherms connect points
    of equal temperature Isobars connect points of
    equal pressure.

23
  • Latitude- The angular distance north or south of
    the equator. A number between 0 (at the equator)
    and 90 (at the poles). Divides the Earth into a
    northern and southern hemisphere. Latitude always
    includes an N or S to indicate the hemisphere.
    The hemisphere can be determined on a map by
    checking to see in which direction the latitude
    increases. If latitude numbers increase going to
    the north, it is a map of the northern
    hemisphere. If numbers increase to the south- it
    is in the southern hemisphere. If your latitude
    is increasing, you are moving away from the
    equator and towards either pole.
  • Lithosphere- The layer of rock that forms the
    solid outer shell of the Earths interior.
  • Longitude- An angular distance east or west of
    the prime meridian. A number between 0-180.
    Always includes a designation E or W to indicate
    the hemisphere. The hemisphere can be determined
    by checking to see in which direction the numbers
    are increasing. Whichever way longitude increases
    indicates the hemisphere the map is depicting.
  • Meridian (of longitude) - A semi-circle on the
    surface of the Earth that connects the north and
    south poles. All meridians are the same length
    and run from pole to pole.
  • Model- A model is a way of representing the
    properties of an object or system. Example a
    globe.
  • Pauses- The boundaries or interfaces of Earths
    atmosphere.

24
  • Prime meridian- A reference or starting point to
    measure angular distance east or west. The prime
    meridian passes through Greenwich, England
    because the English were the first navigators to
    establish the coordinate system. The prime
    meridian has a longitude of 0
  • Profile- The side view of an areas landscape a
    cut-a-way view
  • Scale A relation between distance on a map and
    distance in the real world. Shown as a ratio, or
    a statement ( 1 inch equals 40 miles) or a s a
    graphic line that indicates the distances.
  • Topographic map- A model or contour map that
    indicates changes in elevation of the Earths
    surface.

25
Topic 3-Earth in the Universe
  • Celestial Object-Any object outside Earths
    atmosphere
  • Universe-All time, matter, energy and space
  • The Big Bang Theory-The theory that the universe
    started about 13 billion years ago with an
    incredible explosion of all matter and energy
    from an infinitesimally small point.
  • Doppler Effect- The effect of wavelengths to be
    stretched longer when an object is traveling away
    from you, and compressed when the object is
    traveling towards you. With light the expansion
    (longer wavelengths) appear red, and the
    compression () shorter wavelength) appear blue
  • Red Shift- The stretching of wavelengths of light
    as objects travel away from a viewer
  • Galaxy-A collection of hundreds of billions of
    stars and gas and dust clouds in one region of
    space.
  • Milky Way Galaxy-The spiral-shaped galaxy to
    which our solar system belongs.
  • Star- a large ball of hydrogen and helium gas
    that produces energy through nuclear fusion.
  • Nuclear Fusion-The process of combining protons
    and neutrons to form larger nuclei and release
    energy.
  • Luminosity- How bright a star would be compared
    to the sun if it was at the same distance as the
    sun.
  • Solar System-A collection of nine planets, 141
    moons, various asteroids, meteoroids, comets and
    dust that all orbit the sun
  • As of September 2004
  • Asteroid- A solid, rocky, usually metallic body
    that orbits the sun. Asteroids have various
    shapes and are smaller than planets. Most orbit
    in a belt between Mars and Jupiter.

26
  • Moon- The only natural satellite of the Earth
  • Comet- A mostly solid object with ice and water
    which evaporates as it approaches the sun leaving
    long and highly visible tails. Most comets are in
    long, highly elliptical orbits and take many
    years to complete one orbit of the sun.
  • Meteors (Meteorites) - Small solid, rocky
    fragments that may enter the atmosphere. Meteors
    burn up, meteorites strike the earth.
  • Impact Crater- The crater left from an impact
    from an asteroid, comet or large meteorite
  • Impact Event- The collision of an asteroid, comet
    or other celestial object with another celestial
    object.
  • Terrestrial Planets- Small diameter, high density
    rocky worlds closest to the sun.
  • Jovian Planets- The gas giants-low in density,
    high mass due to large size, large diameters.
  • Rotation- the spin on an imaginary axis that runs
    through the center of a planet.
  • Revolution- The orbit of a celestial object
    around the sun.
  • Ellipse- A conic section shaped like an oval with
    tow points called foci. Bodies in the solar
    system orbit the sun in elliptical orbits with
    the sun at one of the 2 focus points

27
  • Foci (focus) - The fixed points in an ellipse.
    The sum of the distance between any point on the
    ellipse and the 2 foci is a constant.
  • Eccentricity- how oval or circular the ellipse
    is. Eccentricity equals the distance between the
    foci divided by the length of the major axis.
    Eccentricity must be between 0 and 1. O is a
    perfect circle, 1 is highly elliptical.
  • Inertia-The resistance to change in motion that
    any object has. Inertia is directly proportional
    to mass.
  • Gravitation- The force of attraction between any
    two objects. Gravity id directly proportional to
    the masses of the objects and inversely
    proportional to the square of the distance
    between them.

28
Topic 4 -Motions of the earth, Moon and Sun
  • Axis (of rotation)-Imaginary axis which planets
    rotate about.
  • Constellation-A group of stars that form a
    pattern and mark a region of the galaxy.
  • Coriolis Effect- The effect of fluids to turn to
    the right in the northern hemisphere and the left
    in the southern hemisphere
  • Eclipse- When a celestial object comes into the
    shadow of another celestial object it is called
    an eclipse.
  • Foucault Pendulum-a freely swinging pendulum. Due
    to inertia it swings in the same direction as the
    earth turns. The pendulum appears to turn but the
    earth is turning. Provides evidence of earths
    rotation.

29
  • Geocentric Model- Earth at the center of the
    solar system/ universe
  • Heliocentric Model-The sun at the center of the
    solar system
  • Local time-time based on earths rotation and the
    position of the sun
  • Phases (of the moon)-The varying amounts of the
    lighted portion of the moon
  • Tides-Cyclic rise and fall of oceans (and some
    large lakes) due to earths rotation and the
    gravitational effect of the moon.
  • Time Zones-A way to solve the problem of local
    times being different everywhere.

30
Topic 5-Energy in Earth's Processes
  • Barrier interactions When energy interacts with
    something in the environment, the energy may be
    reflected, absorbed or transmitted through the
    substance, but it is always conserved.
  • Calorie- A unit of energy most usually associated
    with food. The quantity of heat required to raise
    one gram of water one degree Celsius.
  • Condensation- The changing of a gas to a liquid,
    requires the gas to release heat energy.
  • Conduction-The transfer of heat energy between
    objects that are in direct contact.
  • Convection- The transfer of heat energy by the
    circulation of fluids. Fluids include anything
    that can flow, not just liquids. Hotter fluids
    have lower densities and rise, while cooler
    fluids have higher densities and sink. Convection
    is the primary method for heat distribution in
    the mantle, atmosphere, hydrosphere, and suns
    interior. These circulating fluids form
    convection currents, also called convection
    cells.
  • Crystallization- The process of changing a liquid
    to a solid with a specific arrangement pattern of
    the atoms or molecules they form crystals.
    Requires a release of energy.

31
  • Electromagnetic energy- (EM) -A type of energy
    that is radiated in the form of electromagnetic
    waves. They are distinguished from each other by
    their wavelengths. In order of increasing
    wavelength, they are radio waves, microwaves,
    infrared (heat), visible light, ultraviolet,
    x-rays and gamma rays. Waves transmit energy, so
    the closer the waves (shorter wavelength) the
    more intense is the radiation.
  • Electromagnetic spectrum-The spectrum of all
    electromagnetic waves. Listed in the ESRT in
    order of increasing wavelength.
  • Energy- The ability to do work. There are many
    forms of energy, and in any interaction energy is
    always conserved. It cannot be created or
    destroyed, but it can change form. Most energy
    ends up as heat energy, a form of energy
    pollution.
  • Heat energy-Infrared EM energy, which travels
    from areas of higher temperature to areas of
    lower temperature.
  • Kinetic energy The energy of any moving object.
    faster speed equals more kinetic energy.
  • Mechanical energy- The energy of an object not
    related to atoms and molecules. Mechanical energy
    is the sum of potential and kinetic energy.

32
  • Melt The process of changing a solid to a
    liquid by the absorption of energy.
  • Nuclear decay- The process of an unstable nucleus
    breaking apart and releasing sub-atomic particles
    and energy.
  • Potential energy The energy from position. A
    roller coaster at the top of a hill has a great
    deal of potential energy. as it coasts down the
    track the potential energy is changed to kinetic
    energy (speed) and heat energy through friction.
  • Radiation- The transfer of heat energy through
    the EM spectrum, usually refers to the infrared
    portion.
  • Refraction The bending of light waves as they
    travel from one material to another material with
    a different density.
  • Solidification- The process of changing a liquid
    to a solid, (freezing) requires a release of
    energy.
  • Specific heat-The quantity of heat required to
    raise one gram of a particular substance one
    degree Celsius.

33
  • Sublimation The term that refers to either a
    change from a gas to a solid (frost) (requires
    energy to be released) or the change from a solid
    to a gas (requires energy to be absorbed).
  • Surface characteristics Determines what will
    happen when energy interacts. Light colors
    increase reflection and decrease absorption,
    while dark colors are good absorbers. Texture
    also affects how the energy is reflected or
    absorbed.
  • Temperature- The measure of the average kinetic
    energy of the particles in a substance.
  • Texture- The roughness or smoothness of a
    surface. Texture affects the amount of EM
    radiation absorbed or reflected. Smooth textures
    are better at reflection than absorption, while
    rough textures are better at absorption than at
    reflection.
  • Vaporization-The changing of a liquid to a gas
    requires the liquid to absorb energy. Also
    referred to as evaporation.
  • Wavelength- The length of one wave from crest to
    crest. As wavelengths increase, the amount of
    energy being transported decreases. When waves
    are close together (short wavelengths) more
    energy is being transmitted.

34
Topic 6- Insolation and the Seasons
  • Angle of incidence-The incoming angle of the
    suns rays (insolation). The higher the angle,
    the greater the intensity of the radiation. Low
    angles, such as at sunrise and sunset spread the
    radiation over a much larger surface area, and so
    its intensity is much less. The amount of
    radiation you are receiving can be determined by
    looking at the size of your shadow. A small
    shadow equals a high intensity, a long shadow
    equals a low intensity. The angle of incidence
    varies with 1) the time of day- its greatest at
    solar noon, 2) latitude its greatest in the
    tropics, and 3) seasons its greatest in the
    summer.
  • Deforestation-The process of cutting entire
    forests down to clear land for human uses. This
    process alters the balance of nature, influences
    global warming and increases the extinction of
    species.
  • Equinox The first day of spring and fall is
    called an equinox. It means the Earth experiences
    equal periods of day and night (12 hours). These
    days are March 21 and September 21.

35
  • El Niño- A warming event in the Pacific Ocean
    surface temperatures which disrupt weather on a
    global scale producing major storms and
    hurricanes.
  • Global warming-The process of raising the
    temperature of the Earth by trapping large
    quantities of greenhouse gasses in the
    atmosphere, primarily through burning fossil
    fuels.
  • Greenhouse gasses-Gasses that absorb large
    quantities of infrared radiation and trap the
    heat in the atmosphere are called greenhouse
    gasses. These gases are primarily carbon dioxide,
    water vapor, and methane.

36
  • Heat budget-The dynamic equilibrium between the
    total amount of heat that an object receives and
    the amount that it radiates.
  • Ice ages-A shift in the heat budget which results
    in more energy being released than absorbed.
  • Insolation- INcoming SOLar radiATION is
    IN-SOL-ATION. Radiation from the sun.
  • Land and Water heating differences Land always
    heats up faster and cools down faster than water
    does. This is because of 4 factors 1) Water has
    a very high specific heat- it takes a great deal
    of energy to change its temperature, 2) change of
    state water can change from a liquid to a gas,
    land does not change states. Energy that is used
    to change the state of matter is not available to
    raise its temperature. This energy becomes latent
    heat, a form of potential energy. 3) transparency
    water is very transparent to radiation, land is
    not at all transparent to radiation. When light
    travels to the bottom of a body of water, it is
    heating up all of that water. The land stops the
    light at its surface and heats up much more
    quickly. 4) Convection currents distribute heat
    in the water. Land is not fluid and has no
    convection currents so all the heat remains at
    the land surface, while it is distributed
    throughout the water.
  • Ozone- A type of oxygen in which three molecule
    of oxygen join together. The ozone layer exists
    in the upper atmosphere (stratosphere) and is
    vital to absorption of damaging ultraviolet
    radiation, which causes skin cancer.

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  • Seasons A change of weather that primarily
    affects the mid latitudes (23½- 66½) Latitudes
    less than 23are mostly warm all year round,
    while latitudes near the poles (above 66) are
    mostly cold all year. The change of seasons is
    caused by three factors. 1) The Earths tilted
    axis at 23½, 2) the fact the Earth revolves
    around the sun once a year, and 3) parallelism
    the Earths axis always points in the same
    direction in space. The Earths orbit around the
    sun is not a perfect circle, it is an oval shape
    called an ellipse. At certain times of the year
    the Earth is closer to or farther from the sun,
    but THE CHANGING DISTANCE DOES NOT CAUSE SEASONS!
    In the northern hemisphere, we are closest to the
    sun in winter, and farthest away in summer. The
    northern and southern hemispheres experience the
    opposite seasons. When we are having winter they
    are having summer, and vice-versa.
  • Solstice The first day of winter and the first
    day of summer is called a solstice. On these days
    either the north pole or the south pole is
    pointed most directly at the sun. The polar
    regions (above 66½ latitude experience either 3
    months of daylight ( the sun never sets) during
    the summer, or 3 months of night (the sun never
    rises) during winter.
  • Sunspot- A darker region of the suns surface
    where the temperature is lower than the
    surrounding areas. Caused by magnetic storms on
    the suns surface and releases massive amounts of
    solar particles (solar storms)
  • Transpiration- The process by which living
    organisms (plants and animals) release water
    vapor into the atmosphere.

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  • Factors affecting the amount of insolation an
    area receives
  • 1. Angle of incidence
  • When the angle of incidence is closest to 90 the
    insolation intensity is the greatest.
  • By day-
  • The angle of incidence is greater at noon than
    any other time of the day.
  • The angle of incidence is the lowest at sunrise
    and sunset.
  • By season-
  • The angle of incidence is the greatest in the
    summer and the lowest in the winter.
  • For NYS, about 72 in summer at noon and 25 in
    winter at noon
  • 2. Cloud cover
  • When the sky is mostly cloudy, there is more
    insolation reflected back into space.
  • When skies are clear, more insolation reaches the
    surface.
  • 3. Earth's shape and latitude
  • Because the Earth is a sphere, the latitudes
    receiving the greatest insolation are those
    closest to the equator. Polar regions receive the
    least amount of insolation because the angle of
    incidence is lowest at these latitudes. The size
    of your shadow is an indicator of the intensity
    of insolation.
  • Small shadow high intensity. Large/long
    shadow low intensity
  • 4. Variation in duration of insolation
  • Because of the Earth's tilted axis, latitudes
    experiencing summer not only receive a higher
    angle of incident insolation, but a longer
    duration as well. 15 hours. Latitudes
    experiencing winter receive the shortest duration
    of insolation., about 9 hours

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  • 5. Time delay in maximum and minimum
    temperatures.
  • Because water has such a high specific heat and
    covers so much of the surface of Earth, the
    seasonal high and low temperatures lag behind the
    seasonal peak of insolation by about a month.
  • Water is absorbing or releasing its stored heat
    (latent heat)
  • The highest temperatures of the summer occur in
    July/August even though the longest day is June
    21. The coldest temperatures usually occur in
    January/February even though the shortest day is
    December 21. The same time delay occurs on a
    daily basis-
  • While the angle of incidence is highest at noon,
    the hottest time of the day is usually late in
    the afternoon. The coolest part of the day is
    usually right around sunrise, and is after
    sunrise on many days.
  • 6. Long term changes in climate
  • These are a result of changes in the amount of
    insolation absorbed or emitted- called the heat
    budget. Earth's heat budget has shifted in the
    past. There have been periods of ice ages and
    warm periods. El Nino and la Nina-between every
    2-10 years-not well understood by scientists.
    Global warming-some scientists believe it is
    caused by the massive burning of fossil fuels,
    others disagree. The role of sunspot activity and
    solar cycles effects on Earth's climate is also
    not well understood. The slight change of the
    tilt of Earth's axis (precession) and
    eccentricity of the elliptical orbit are
    additional factors not well understood. Volcanic
    eruptions also affect the amount of insolation
    received-ash clouds block sun from reaching the
    surface.
  • 7. Color and texture light colors reflect, dark
    colors absorb. Rough surfaces absorb, smooth
    surfaces reflect.

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Topic 7-Weather
  • Air mass- A large body of air in the troposphere
    with similar characteristics
  • Air pressure gradient- The difference in air
    pressure over a given distance. Close isobars
    indicate high pressure gradient and windy
    conditions.
  • Anemometer- An instrument used to measure wind
    speed.
  • Atmospheric, barometric, or air pressure- The
    pressure of the air in a given location. Standard
    pressure of 1 atmosphere equals 1 bar, or 14.7
    lbs. /sq. in. or 29.92 of mercury, or 33 of
    water.
  • Atmospheric transparency- How transparent the
    atmosphere is to insolation. Less transparent,
    due to high cloud cover or pollution, means more
    sunlight is reflected or absorbed, and less
    reaches the ground.
  • Barometer- An instrument used to measure air
    pressure.
  • Cloud cover- The fraction of the sky that is
    covered by clouds.
  • Cold front- Boundary of an advancing cold air
    mass. The heavier, underlying cold air pushes
    forward like a wedge.
  • Cyclone- Low pressure storms

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  • Cyclonic storm- Low pressure storms in
    mid-latitudes, and Indian Ocean also called
    hurricanes in the Atlantic, and typhoons in the
    Pacific.
  • Dew point- The temperature at which relative
    humidity reaches 100.
  • Front- Where two air masses of different
    characteristics meet.
  • Humidity- Amount of water vapor in the
    atmosphere. warm air can hold more vapor than
    cold air can.
  • Isobar- Isolines of equal pressure are isobars.
  • Jet stream- Bands of easterly moving air at the
    top of the troposphere blowing 200 MPH or more.
  • Monsoons- Regular and severe weather changes
    caused by shifting winds.
  • Occluded front- Boundary of opposing wedges of
    cold air masses formed when a cold front forces
    warm air up, off the ground.

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  • Planetary wind belts- Winds moving in
    predominantly one direction. They are due to
    winds blowing from high pressure to low pressure
    areas and the spin of the Earth (Coriolis
    Effect).
  • Polar front- An ever changing boundary in
    mid-latitudes between cold air masses from the
    poles and warm air masses from the equator.
  • Precipitation- The falling of liquid or solid
    water from clouds.
  • Probability- Chance of occurrence of certain
    types of weather. These are predictions based on
    weather models, and past performance.
  • Psychrometer- An instrument used to measure
    relative humidity. (A wet-bulb and dry-bulb
    thermometers and a table)
  • Radar- Reflected electro-magnetic energy that is
    used to give a 3-dimensional view of weather.
    Acronym for RAdio Detection And Ranging
  • Relative humidity- The ratio of the amount of
    water vapor in the air to the maximum amount that
    could be dissolved in the air.

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  • Stationary front- Two masses of air with
    different characteristics that remain in the same
    position.
  • Station model- Symbols and a circle used to
    indicate weather variables for a specific site.
  • Troposphere- The part of the earths atmosphere
    directly above the surface. Most weather occurs
    in the troposphere.
  • Visibility- How far you can see along Earths
    surface in miles.
  • Warm front- Boundary of an advancing warm air
    mass. Because colder air is heavier, warm air is
    forced to rise as it advances.
  • Water vapor- Gaseous water in the atmosphere.
  • Weather variables- temperature, pressure, wind,
    moisture, cloud cover, precipitation, and storms.

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Topic 8 -Water and Climate
  • Capillarity-The attractive force between water
    molecules that can oppose the force of gravity.
    Capillarity is greater when the tube diameter is
    smaller.
  • Climate-The weather conditions at a location over
    a long period of time
  • Ground water-The sub-surface water stored below
    the water table is ground water. 2/3 of all
    non-frozen freshwater on earth is ground water.
  • Hydrologic cycle- See water cycle
  • Infiltrate-As water slowly moves through open
    spaces in the ground it is said to infiltrate the
    ground
  • Permeability- The ability of a material to allow
    fluids to pass through is its permeability. The
    permeability rate is the speed at which fluids
    can infiltrate the ground.
  • Porosity- The amount of open space between
    particles of dirt and sediment is the porosity of
    the soil.
  • Prevailing winds- The direction from which the
    wind usually blows at a given location
  • Runoff-As precipitation flows over the surface of
    the earth back towards the oceans it is described
    as runoff.

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  • Seep-The process of water infiltrating the ground
  • Sorted- Sediments are said to be sorted when they
    are close in size to one another.
  • Stream discharge- The volume of water that a
    stream discharges over a given period of time is
    the stream discharge.
  • Unsorted- When sediments are mixed sizes they are
    said to be unsorted. Usually from glacial
    deposition.
  • Urbanization- The development of large areas,
    including road building, parking lots and
    buildings. Urbanization decreases infiltration
    and increases runoff.
  • Water cycle- A model used to show the movement
    and phase changes of water at or near Earths
    surface.
  • Water retention- Precipitation can be stored or
    retained on the land as ice or snow, or on the
    leaves of plants and trees
  • Water table- The interface between the area of
    saturation and zone or aeration is the water
    table. Ground water is at and below the water
    table.

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Topic 9 - Weathering and Erosion
  • Abrasion-Rocks scraping against other rocks
    primarily through glacial erosion produces
    abrasions. Abrasion has the effect or rounding
    sharp pieces of rock.
  • Breaking wave-When a wave reaches shallow water
    it is unable to support its height and breaks
    in a forward rush of water.
  • Chemical weathering-This occurs when carbon
    dioxide or sulfur dioxide dissolve in water and
    then dissolve rocks. Plant roots may also secrete
    mild acids that contribute to chemical
    weathering.
  • Delta-A delta is a depositional feature formed by
    deposition of sediments carried by a stream over
    a long period oft time.
  • Erosion-The transportation of sediments through
    running water, glacial ice, wind, waves, and mass
    movements is the process of erosion. Erosion
    almost always moves particles to lower
    elevations, wind is the exception.
  • Finger Lakes-These are long narrow lakes in
    U-shaped valleys, left behind as glaciers melt.
    They are usually dammed at one end with a pile of
    loose debris.
  • Flood plain-During times of floods when a stream
    overflows its banks it may flow out onto a wider
    valley and deposit sediments in the flood plain.

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  • Glacial groove-The gouges left behind by a
    glacier are glacial grooves.
  • Glacier-A naturally formed mass of ice which
    accumulates over long periods of time. Glaciers
    can form in mountains and move down a valley,
    (valley glacier) or cover entire continents
    (Greenland, Antarctica). These are continental
    glaciers.
  • Mass movement- Rock slides, mud or debris flows,
    creep and slump are examples of mass movements.
    The primary force causing mass movements is
    gravity.
  • Meander-A physical feature carved by a river.
    Meanders are snake like bends and curves in a
    river or stream.
  • Physical weathering- Frost action, freeze-thaw
    cycles, plant root growth, and abrupt temperature
    changes can cause rocks to crack and breakdown
    into smaller pieces.
  • Sandbar-In the zone of breaking waves, sediments
    deposited can form a barrier parallel to the
    shore called a sandbar.
  • Sandblasting-This occurs when winds pick up
    sediments and blow them against rocks causing
    abrasion.

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  • Sediments- Particles of rock which have been
    broken down into small pieces by the process of
    weathering.
  • Stream-When running water is confined to a narrow
    channel a stream is formed.
  • Stream channel shape- The shape of the bedrock or
    loose materials that confine a stream is the
    stream channel shape.
  • Tributary- A smaller stream that joins a larger
    stream is a tributary.
  • U-shaped valley-The shape of a valley carved by
    glaciers, the sides are cut away by the ice
    leaving the U shape.
  • V-shaped valley-The shape of a valley carved by a
    stream or river is V-shaped because the stream
    cuts deeper over time.
  • Watershed-The area of land drained by a stream or
    series of streams is a watershed.
  • Weathering-The chemical and physical breakdown of
    rocks at or near Earths surface.

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Topic 10-Deposition
  • Barrier Island-An island created by the
    deposition of sand offshore, and held in place by
    growing vegetation.
  • Deposition-The process by which sediments are
    released, settled from, or dropped by an
    erosional system.
  • Drumlin-Streamlined, oval shaped moraines that
    look like an inverted spoon.
  • Kettle Lake-A lake formed by the depression due
    to the weight of a glacier and the melting of the
    ice.
  • Moraine-The unsorted sheets or piles deposited on
    the sides or at the end of a glacier.
  • Outwash Plain- The running water that moves away
    from the terminus of a glacier may move out in a
    fan-shaped pattern that is called an outwash
    plain.

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  • Sand dune-A large pile of sand deposited by wind.
    Sand dunes have a steep gradient on the windward
    side (side facing the wind), and a gradual slope
    on the leeward side (side facing away from the
    wind.) This feature of sand dunes can be used to
    determine the direction from which the wind
    blows. Sand dunes migrate as sand on the
    windward side is blown around to the leeward
    side.
  • Sorted sediments-Sediments that are similar in
    size and shape, usually deposited by running
    water or wind.
  • Unsorted sediments-Sediments that are very
    different in size and shape, usually the result
    of glacial deposition or mass movements.

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Topic 11- Earths Materials
  • Bioclastic sedimentary rocks-Rocks that were
    formed from living organisms, such as shells
    forming calcium carbonate limestone rocks.
  • Chemical sedimentary rocks-Rocks formed from the
    chemical precipitation of dissolved chemicals,
    usually salts.
  • Clastic sedimentary rocks-Rocks that are largely
    composed of solid sediments such as sand in
    sandstone.
  • Cleavage-The tendency of a rock to break along
    lines of weaker atomic bonds forming smooth
    planes, and specific angles is its cleavage.
  • Contact metamorphism- The metamorphism that
    occurs when older rocks come into direct contact
    with hot magma.
  • Crystal shape-The outward geometric shape of a
    mineral is determined by the crystal shape.
  • Crystal structure-The specific arrangement of
    atoms in a material.
  • Extrusive igneous rocks-Igneous rocks that form
    on the surface of the Earth- exposed to the
    atmosphere.
  • Foliation-Large mineral crystals often in layers.

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  • Fossil-Evidence of former life preserved in rock.
  • Fracture-If a material lacks specific lines of
    weaker atomic bonds, it will break with uneven
    surfaces. This is called fracture.
  • Hardness-The resistance a rock offers to being
    scratched is its hardness. A rock that can
    scratch another is harder than the rock that was
    scratched.
  • Igneous rocks- Rocks formed when liquid magma or
    lava cools and hardens.
  • Inorganic-Not composed of anything that is or was
    alive.
  • Intrusive igneous rocks-Igneous rocks that form
    beneath the Earths surface.
  • Luster-The shine from an unpolished rock, or the
    way it reflects light is its luster
  • Magma-Liquid rock beneath Earths surface- not
    exposed to the atmosphere.
  • Metamorphic rocks-Rocks that have been changed
    under temperature and pressure from sedimentary
    or igneous rocks.
  • Metamorphism-The process through heat and
    pressure of changing a rocks composition and
    mineral structure.

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  • Mineral- A naturally occurring, inorganic,
    crystalline solid, with a definite chemical
    composition
  • Mineral crystal-Individual grains of minerals.
  • Mineral resources-Earths resources including
    minerals, rocks and fossil fuels.
  • Organic-Refers to anything that is or was alive.
    Generally, organic materials are carbon based.
  • Precipitation of minerals-The result of
    evaporation, saturation with dissolved minerals,
    or changes in temperature.
  • Regional metamorphism-Metamorphism that occurs in
    a large area or region.
  • Rock cycle- A model used to show the various
    stages of rocks from sedimentary to metamorphic
    or igneous.
  • Sedimentary rocks-Rocks that form from an
    accumulation of sediments.
  • Streak-The color of finely crushed residue or
    powder of the mineral
  • Texture-The size, shape and arrangement of the
    materials in a rock are its texture.

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Topic 12- Earths dynamic crust and Interior
  • Asthenosphere-A portion of the upper mantle just
    below the crust. This is a plastic layer that the
    plates move around on.
  • Continental crust-Crust at the continents-thicker
    than oceanic crust. Primarily composed of less
    dense granite.
  • Convergent plate boundary-A boundary where two
    plates move together in a head-on collision.
    These cause mountain building if both plates are
    continental, and subduction if one plate is
    oceanic.
  • Crust-The top part of the lithosphere.
  • Divergent plate boundary-A boundary where two
    plates are moving apart from one another.
  • Earthquake-A natural, rapid vibration of the
    lithosphere. Usually caused by plate motions.
  • Epicenter-The location on the surface of the land
    or water directly above the location where an
    earthquake originated.

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  • Faulted-Rock layers that are offset from the
    position in which they formed. Faulting can be
    vertical or horizontal.
  • Folded- Rock layers that are bent or tilted.
  • Hot spot-A place where the crust is especially
    thin. There may be geothermal or volcanic
    activity associated with hot spots.
  • Inner core-The central core of the earth,
    composed of solid iron and nickel.
  • Island arc-A region of islands created by
    volcanoes from a hot spot.
  • Lithosphere-The layer of rock that forms the
    outer layer of Earths shell at the top of
    Earths interior is the lithosphere.
  • Mantle-The thickest part of earths interior,
    located below the lithosphere. The mantle
    contains 80 of earths volume and is separated
    from the crust by a layer called the Moho.
  • Mid-ocean ridge-A region where plates diverge and
    new oceanic crust is formed.
  • Moho-A thin layer that separates the crust from
    the mantle.

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  • Oceanic crust-Thinner crust portions beneath the
    oceans primarily composed of higher density
    basalt.
  • Ocean trench-In regions of subduction, trenches
    are formed which are the deepest regions of
    earths oceans.
  • Original horizontality- The concept that
    sediments and lava flows occur originally in
    horizontal layers.
  • Outer core-The fluid portion of earths core,
    mostly liquid iron and nickel
  • Plate tectonic theory-The theory that the plates
    move around at the surface of the Earth.
  • P-waves-The primary earthquake wave. P-waves
    cause particle vibration in the direction the
    wave travels. (Longitudinal waves)
  • Subduction-The process of a more dense plate
    sinking beneath a less dense plate.
  • S-waves-Secondary waves cause particle vibration
    at right angles to the direction of wave
    propagation. (Transverse waves).

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  • Seismic waves-The release of energy during an
    earthquake is recorded as a seismic wave.
  • Tectonic plates-Lithospheric plates, Plates, -
    sections of crust are divided into oceanic and
    continental plates.
  • Transform plate boundary-The boundary between two
    plates that are sliding past each other.
  • Tsunami-A wave generated by an earthquake.
    Tsunamis can be extremely large and cause extreme
    property damage and loss of life.
  • Uplift-The force that lifts portions of the crust
    to higher elevation. Uplift is usually caused by
    a build up of magma below the surface or by
    plates colliding.
  • Volcanic eruption-The release of gasses, steam,
    ash, pyroclasts, and molten rock (lava) is an
    eruption.
  • Volcano-A mountain formed from extrusive igneous
    rocks.
  • Young mountains-Created by convergent plates
    colliding and forcing the lithosphere to be
    uplifted.

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Topic 13 - Interpreting Geologic History
  • Geologic age - the age of the Earth is so
    immense that its age is referred to as geologic
    time. If the age of the Earth was represented
    with a stack of paper sheets, and each sheet of
    paper represented 2000 years, the stack of paper
    would have to be about 750 feet high to represent
    the Earth.
  • The geologic rock record is very much like a
    bunch of 1000 piece jigsaw puzzles. All over the
    world, at every location there is the same
    puzzle. The problem is, that no where is there a
    puzzle with all 1000 pieces in the box. Some
    puzzles are missing 50-100 pieces and others are
    missing several hundred pieces. No complete
    puzzle can be completed, but because all the
    puzzles make the same picture, we can get an idea
    what is missing at our location by seeing another
    puzzle that is not missing those pieces. This
    process of filling in the missing pieces is
    called correlation. The pieces are missing due to
    erosion. It is erosion that removes puzzle pieces
    from the rock record. These missing sections are
    called unconformities.
  • Absolute age-The absolute age of a rock in years,
    usually a range like 410-425 million years.
    Determined with radioactive dating.

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  • Carbon-14 dating- The process of using Carbon-14,
    an isotope of carbon, for absolute dating. The
    use depends on knowing the original amount of
    Carbon-14 present and the amount of the decay
    product.
  • Correlation-Correlation is the process of showing
    that rocks from different places are the same or
    similar in age. This process fills in the missing
    pieces of the geologic rock record using among
    other techniques- index fossils.
  • Extrusion-When igneous rock flows out onto the
    surface and solidifies, it forms an extrusion.
  • Faults- a break between rock layers. Faults are
    always younger than the rocks they cut across.
  • Fossil-The remains of former life, preserved as
    rocks. Almost all fossils are found in
    sedimentary rocks. Igneous and metamorphic rock
    processes destroy fossils.
  • Geologic time scale-Divisions of the geologic
    time based on changing fossil evidence. The
    divisions are, from longest to shortest, eons,
    eras, periods, and epochs. Much of the
    information regarding these time units is in your
    reference tables.

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  • Half-life-The time required for half of a
    radioactive sample to decay is its half-life. By
    knowing the half-life of an isotope and the
    fractions that are decayed and still radioactive,
    we can determine the age of a rock or artifact.
    Because we need a reasonable fraction to look at,
    this techniques works best when at least 1
    half-life has gone by (not too much still
    radioactive) and no more than 6 half-life's have
    gone by (too much decayed).
  • Inclusion- When a piece of older rock is encased
    in a younger rock, it is an inclusion. Inclusions
    form as magma pushes through older rock and is
    not hot enough to melt the older rock. It may
    completely surround the older rock forming an
    inclusion. Inclusions are always older than the
    rock that surrounds them.
  • Index fossil-Index fossils are used in
    correlation. To be an index fossil, 2 conditions
    must be met. First, the fossil must have lived
    over a wide geographic area so that its remains
    have a large horizontal distribution. Second, the
    life form must have lived for a relatively short
    period of geologic time before it went extinct.
    If it lives for a long time period and can be
    found in many different rock layers it is not
    useful in correlating bedrock.

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  • Intrusion- When magma squeezes into existing
    rocks and crystallizes underground it forms an
    intrusion. Intrusions are younger than any rock
    they cut through. Intrusions will cause contact
    metamorphism. If we see an intrusion covered by a
    rock layer that does not show contact
    metamorphism we know that the rock layer formed
    after the intrusion. If we see contact
    metamorphism on the rock layer above the
    intrusion, it tells us that the rock layer was
    there when the intrusion occurred.
  • Isotope-A variety of an element with a different
    number of protons than the most common variety of
    that element is an isotope. It must have the same
    number of protons- change the number of protons
    and you change elements.
  • Organic evolution theory-The theory that life
    forms change over time.
  • Outgassing- The process of gasses seeping out of
    Earth's interior.
  • Principle of original horizontality A fancy way
    to say that sedimentary rocks form in horizontal
    layers. If the rocks we are looking at are no
    longer flat, then the tilting or folding
    (tectonic forces) happened since they were
    formed.
  • Principle of superposition- The idea that the
    bottom layer of a series of rock layers is the
    oldest, and that younger layers are on top of the
    older layers. New sedimentary rocks form on top
    of older sedimentary rocks.

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  • Radioactive dating-The process of using the half
    life of a radioactive isotope and the ratio
    between the existing amount and the original
    amount to date rocks in an absolute manner.
  • Radioactive decay-The process of an elements
    nucleus breaking apart and releasing particles
    and energy is radioactive decay. This breaking
    apart is called fission.
  • Radioactive decay fractions These are the
    fractions geologists use to determine absolute
    age. There are always 2 fractions which will add
    up to the whole (1) The first is the fraction
    that is still radioactive (parents). This
    fraction is cut in half each time 1 half-life
    goes by. It always has a 1 for its numerator and
    its denominator continually doubles. The other is
    the fraction that has decayed (daughters). This
    fraction always has the same denominator as the
    corresponding parent, and its numerator is the
    denominator minus 1. Example after 3 half
    life's- Parents equal ½ ¼ 1/8
  • daughters equal ½ ¾ 7/8
  • The 1/8 and the 7/8 add up to the whole (1)
  • Parents approach 0 but will never reach it while
    daughters approach 100 without ever reaching it.
  • Radioactive isotopes continue to decay forever!
    Nothing affects their decay- not temperature,
    pressure, size or age of the sample!

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  • Unconformity- A buried, erosional surface of
    rock, in which older rock layers are missing from
    the geologic record. Without an atmosphere and
    weather a planet would not have any
    unconformities.
  • Uranium-238- An important radioactive isotope of
    uranium which helps scientists to date rocks.
    Half-life and disintegration are on the front
    cover of the reference table.
  • Volcanic ash- The dust and particles expelled by
    volcanoes during eruptions is volcanic ash. These
    serve as specific age markers in the glacial and
    geologic records. The glacial ice can be dated
    absolutely by examining the lines in ice cores.
    Every volcano emits a composition of dust and ash
    that is unique like a volcanic fingerprint.
    These are extremely useful markers in the rock
    record that assist the correlation process.
    Impact events (asteroid collisions) produce the
    same effect.

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Topic 14 - Landscape Development and
Environmental Change
  • Escarpment-Cliffs that form where rocks of
    different hardness erode at different rates.
  • Landscape- Landscape or topography are the
    features of the surface on top of the
    lithosphere.
  • Landscape region- The characteristics of a region
    including bedrock structures, elevation, stream
    drainage patterns, and soil characteristics.
  • Mountain- An area of high elevations compared to
    the surrounding area. Usually includes areas of
    steep gradients, and many changes in slope.
  • Plain-Usually composed of sedimentary rock layers
    in a horizontal structure at lower elevations.
  • Plateau-An area of high elevation with a
    horizontal structure.
  • Ridges-Formed from more resistant rock layers,
    usually in long, narrow bands called ridges.
  • Stream drainage pattern-The shape o
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