Earth Science

Earth Science
A place for my students to get some help in Earth Science

Wednesday, March 21, 2007

•Part D of the Physical Setting/Earth Science Regents Exam is referred to as the Laboratory Performance Exam.
•Part D consists of a series of 6 tasks that are to be performed before the final exam.

These tasks are on the following topics:

Rock and Mineral identification

Density

Sun angle

Deposition
Graphing
Settling time

Station1 Mineral ID

Identification - Using a mineral Identification kit and key, the student will determine the characteristics of two mineral samples and identify each sample by name.

Luster
1. describes the way light is reflected from the freshly cut surface of a mineral
2. luster falls into two categories metallic or nonmetallic

Metallic
1. looks like metal
2. have a hard shiny look
Nonmetallic
1. can be shiny but the mineral lacks the metallic appearance
2. does not look like metal

Streak
1. is the true color of the mineral in powered form
2. one performs a streak where the mineral by rubbing the mineral on a streak plate
3. After rubbing the mineral on the streak plate you should see a color if you do not see a color rub your finger on the area that us just rub the mineral over.
4. if your finger come back with nothing on it then the mineral is none to white
5. it is important to note the streak may not match the physical color of the mineral

Hardness
1. hardness of glass if 5.5
2. do to a hardness test you scratch a piece of glass
3. lay the piece of glass flat on the desk and hold it in place
4. than press the mineral onto the glass and try to scratch the glass (don’t be shy you may have to press a little hard)
5. if the mineral scratches the glass the than the minerals hardness is harder than glass
6. if the mineral does not scratch the glass than the minerals hardness is less than glass

Cleavage
1. the mineral breaks readily along a flat surface
2. cleavage also occurs a angles, but always along a flat surface

Rock ID

§Classification - Using rock identification charts, the student will classify two rock samples to identify each sample as Igneous, Metamorphic, or Sedimentary and state a reason for each classification based on the observed characteristics of the rock samples.

Sedimentary Rocks
1. After burial of sediments, over time natural processes and high pressure will cause these sediments to bond and form sedimentary rock.
2. Sedimentary rocks are classified as clastic, chemical or organic depending upon how they were formed.
3. Clastic sedimentary rocks are classified based upon grain (particle) size.
4. Chemically formed sedimentary rocks form from chemical precipitates and evaporites.
5. Organic and chemical sedimentary rocks are primarily identified through composition and texture.
6. Fossils are found almost exclusively in sedimentary rocks.

Igneous Rocks
1. Rock types are based upon how they form. Most rocks are composed of one or more minerals.
2. Igneous rocks form by the crystallization (cooling and solidification) of molten magma.
3. Crystal size, mineral composition, density and color are used to identify most igneous rocks.
4. Intrusive (plutonic) rocks can be distinguished from extrusive (volcanic) rocks based on crystal size.
5. Felsic rocks such as granite are commonly found on continents, while mafic rocks such as basalt are more commonly found on the ocean floor.

Metamorphic Rocks
1. Metamorphic rocks form through crystallization/recrystallization without melting under high temperature and pressure.
2. Metamorphic rocks are classified according to their texture, composition including foliation (mineral alignment), banding (the separation into distinct distorted layers) and high density.
3. It is possible to infer the parent rock from the mineral composition and structure of most metamorphic rocks.
4. Contact metamorphism is the changing of existing rock by being near liquid rock (magma or lava).
5. Regional metamorphism is the changing of very large (thousands of square kilometers) areas of rock that undergo intense heat and pressure. This is generally associated with mountain building.
6. The rock cycle is a model designed to show how the different rock types are interrelated and the potential pathways rock material may follow in the transformations from one rock typed to another.

STATION THREE Sun's path

Angular Measurement - Using a plastic hemisphere that models the apparent path of the sun, an external protractor, a metric ruler, and masking tape, the student will locate the position of the sun at a given time and measure the distance between that position and a fixed point.

1. get your reference time, which is your starting time
2. find you given time
3. take a piece of masking tape about 6 inches in length
4. place it along the dotted line on the plastic sphere
5. there will be an X of a letter on the sphere where you should start you piece of tape
6. draw a straight line at the starting point
7. take your protractor and measure out the distance the sun has traveled (REMEMBER THE SUN TRAVELS 15° EVERY HOUR)
8. mark off every 15°until you reach your given time
9. write down your total degrees in the space provided
10. once you finish marking off the hours carefully pull your tape off the globe (DO NOT TANGLE IT)
11. place the piece of tape on the space provide for you
12. use the centimeter ruler and measure the distance between your reference time and your given time
13. write down you distance in the space provided
14. remember round to the nearest tenth (one decimal place)

Station 4
Mass-Density - Using a balance, a mineral density chart, and a calculator, the student will find the density, determine the mass, and calculate the volume of a given mineral sample.

Station 5
§Settling Time - Using a column of fluid, three sizes of plastic particles of the same density, a stopwatch, and a calculator, the student will determine the average settling time for each of the three sizes of particles.

Station 6
§Graphing - Using data
obtained from station 5,
the student will construct a line graph of average settling time vs. particle diameter. Then the student will determine the settling time for another given particle diameter using their graph.

posted by James | 9:48 AM

100 Facts to know for the Earth Science Regents

1. If you cut an object in half or change its shape, its density stays the same.
2. The maximum density of water is in the liquid state at 4C.
3. The density of water is 1.0 g/ml.
4. Most changes in the environment are cyclic and predictable (sun's path, seasons, etc.)
5. In a change, energy is exchanged at an interface.
6. Nature is always trying to reach and maintain a state of dynamic equilibrium.
7. The shape of the earth is an oblate spheroid, slightly flattened at the poles and bulging at the equator.
8. Viewed from space, the earth appears to be perfectly flat and smooth.
9. The altitude (degrees above the horizon) of Polaris, the north star, is equal to the latitude of the observer anywhere in the northern hemisphere. This proves that the earth has a curved surface.
10. The rate at which a field value (elevation, temperature, pressure, etc.) changes from place to place within a field is called gradient. Gradient (with elevation fields) can be thought of as steepness.
11. The apparent daily motion of celestial objects is from east to west across the sky at a constant rate of 15/hour.
12. The geocentric model of earth motions has a non-moving earth at the center.
13. The heliocentric model of earth motions has a rotating sun at the center, with celestial objects (like earth) revolving around it.
14. The earth's rotation can be proved by the Coriolis effect, star trails, and the Foucault pendulum. This is explained by the heliocentric model, but not by the geocentric model.
15. The eccentricity of an ellipse describes how round or flat the orbit is. Rounder orbits have a number closer to 0.0, while flatter orbits have a number closer to 1.0. (According to the E.S.R.T. the eccentricity of earth's orbit is 0.017 - a slightly eccentric ellipse.)
16. The gravitational attraction between 2 bodies in space increases as they get closer (or gain mass) and decrease as they get farther apart (or lose mass).
17. The greater the gravitational attraction between two bodies in space, the faster the orbiting body travels. (ex: Planets travel faster when they are closer to the Sun.)
18. In an elliptical (oval) orbit, PE is greatest at aphelion (farthest away) and KE is least. At perihelion (closest point) KE is greatest and PE is least.
19. All matter radiates electromagnetic energy if its temperature is above absolute zero (-273C or 0K). The higher the temperature, the more energy radiated.
20. Electromagnetic energy can be refracted (bent), reflected (bounced), scattered, or absorbed when it comes in contact with a material.
21. Energy can be transferred by conduction in solids (direct molecular contact), convection in fluids (gases and liquids) because of density differences, or by radiation (can occur in a vacuum/no medium).
22. Energy always goes from source to sink.
23. Temperature is the measurement of average kinetic energy of a substance.
24. Energy lost or gained during a phase change is called latent heat (hidden heat).
25. No change of temperature occurs during a phase change. Heat energy is used (or stored) in order to make the change of phase.
26. Kinetic energy is energy of motion. Potential energy is stored energy (such as the height of an object).
27. Heat energy is the total kinetic energy of a sample of matter.
28. A calorie is a unit of heat energy equal to the amount of heat needed to raise the temp. of 1 gram of water 1C.
29. The higher the specific heat of a substance, the more energy needed to raise its temp. (ex: Liquid water requires a large amount of heat because it has a high specific heat.)
30. Evaporation is a cooling process! Condensation is a heating process!
31. Latent heat is gained by a substance when it goes from solid to liquid to gas (temp goes up). Latent heat is lost by a substance when it goes from gas to liquid to solid. (temp. goes down).
32. Insolation (sunshine) is the incoming solar radiation received by the earth from the sun.
33. Intensity (strength) of radiation is the rate at which energy is reradiated from a body; the higher the temp. of the body, the more intense the radiation.
34. Intensity (strength) of insolation is the rate at which solar energy is received by a given area of the earth's surface per unit of time.
35. Only a small portion of the energy given off by the sun is visible to humans (visible light). Other energies include X-rays and Gamma rays (high frequency, short wavelength, dangerous) and infrared or AC generator waves (lower frequency, longer wavelength, safer).
36. The angle at which the sun's rays strike the earth's surface is called the angle of insolation.
37. Solar rays that strike the earth's surface at a 90 angle are called direct or vertical rays.
38. The lower the angle of insolation (the higher the latitude), the lower the temperature and the lower the temperature.
39. Solar noon (when the sun is highest in the sky) is when the angle of insolation is the highest. Maximum temperatures happen around 2-3 PM each day.
40. Only areas of the earth between the Tropic of Cancer (23.5N) and the Tropic of Capricorn (23.5S) receive the direct (vertical) rays of the sun.
41. From the U.S., an observer must look SOUTH to see the sun at solar noon. Shadows will point north at solar noon.
42. The vertical ray of the sun strikes the earth at 23.5N on June 21st (Summer Solstice); at the Equator on Sept. 21 and Mar. 21st (Equinoxes); and at 23.5S on Dec. 21 (Winter Solstice).
43. Seasons are caused by the revolution the revolution of the earth around the sun, the tilt (inclination) of the earth's axis (23.5), and the parallelism of the earth's axis in orbit.
44. As latitude increases, the intensity of insolation decreases.
45. Duration of insolation is the number of daylight hours at a given location (length of day).
46. In NY State, duration of insolation is greatest on June 21st and least on Dec. 21st.
47. If a body gives off the same amount of radiant energy as it receives, it is in radiative balance.
48. The highest temp. of the year occurs approx. 6 weeks after the maximum intensity and duration of insolation. The lowest temp. occurs approx. 6 weeks after the minimum intensity and duration of insolation.
49. Incoming energy from the sun is mostly short-wave radiation. After it is absorbed by the earth's surface, the energy is reradiated as long wave infrared (heat) radiation. (terrestrial radiation) This is the main source of energy for the earth's troposphere.
50. Outgoing long wave infrared radiation (heat) is absorbed by water vapor and carbon dioxide in the atmosphere. This causes the greenhouse effect!
51. The higher the latitude, the lower the temperature; the higher the altitude, the lower the temperature.
52. Water has a higher specific than land. Therefore, coastal regions do not "warm up" and "cool down" as quickly as inland areas. Inland regions have a greater range of temperatures.
53. The higher the air temp., the lower the pressure. The lower the temps., the higher the air pressure.
54 The more moisture the air contains, the lower the pressure (low and moist). The less moisture the air contains, the higher the pressure (high and dry).
55. As air rises it expands and cools; as air descends (goes down) it gets compressed and warms.
56. The warmer the air, the more water vapor it can hold.
Remember this chart...
Temperature
Moisture
Weather
High Pressure
Cool
Dry
Clear
Low Pressure
Warm
Moist
Stormy
57. Dewpoint is the temperature at which air becomes saturated with water vapor.
58. The air can become filled with water vapor (saturated) if either water vapor is added or the temperature cools to the dewpoint.
59. Relative humidity is the comparison between the amount of moisture in the air and the amount the amount the air can possibly hold at that temperature.
60. As dewpoint temp. and air temp. get closer together, relative humidity will increase and the probability of precipitation will increase.
61. Winds are named for the direction from which they come (North winds come from the north).
62. Air always moves from areas of high pressure to areas of lower pressure (wind). The greater the difference in pressures, the stronger the wind.
63. The closer the isobars on a weather map, the greater the wind speed in that area.
64. Air masses are huge bodies of air in the troposphere with similar temperature, moisture, and pressure characteristics. They are named for the area over which they form.
65. Maritime air masses are moist, continental air masses are dry. Polar air masses are cold, tropical air masses are warm, and arctic air masses are very cold.
66. Air masses (and storms) in the United States are "pushed" by the jet stream from west to east (and then northeast) across the country.
67. Cyclones (low pressure) circulate counter-clockwise and toward the center. Anticyclones (high pressure) circulate clockwise and away from the center.
68. The interface between two air masses is called a front. Cold fronts cause brief, heavy precipitation and a drop in temps. Warm fronts cause long, light precip. and a rise in temps.
69. Condensation in the atmosphere releases energy that is used as "fuel" for storms.
70. Permeability is the ability of the soil to allow water to pass through. The larger the soil particle size, the larger the spaces between particles, and the greater the permeability.
71. Porosity is the amount of open space in a soil. As long as the shape is the same, porosity is always equal, regardless of particle size.
72. Pollution occurs when the environment is contaminated with too much of either a natural or man-made substance.
73. Physical weathering of rock is the break down of rock into smaller pieces; chemical weathering involves breaking down the rock by changing it chemically.
74. Water expands when it freezes! (frost action)
75. Smaller particles weather faster than larger chunks of equal volume because the smaller hunks have more surface area.
76. Erosion is the transport of sediments by wind, water, and ice. Gravity is the driving force of all erosion. Water is the most common erosional agent.
77. Rounder, larger, and denser particles will be deposited faster (on the bottom); flatter, smaller, and lower density particles will be deposited last.
78. Sedimentary rocks are formed by the compaction and cementation of sediments or by the evaporation and precipitation of ionic minerals in water (especially ocean water).
79. Metamorphic rocks are formed by heat and pressure on existing rocks and are characterized by higher density, banded crystals, and deformed layers.
80. Igneous extrusive rocks form from the rapid cooling of liquid magma close to the earth's surface and have fine-grained (small crystal) texture. Igneous intrusive rocks form from the slow solidification of magma deep underground and have a coarse-grained (large crystal) texture.
81. The deeper the magma is beneath the surface when it cools, the slower it solidifies and the bigger the crystals. The closer to the surface it cools, the faster it solidifies and the smaller the crystals.
82. Faults, folds, tilts, and igneous intrusions in rock layers are always younger than the rock they cut through.
83. A rift is a place on the ocean floor where new basaltic rock is forcing its way up onto the surface in a spreading pattern. As you travel away from the rift (mid-ocean ridge) the ocean floor gets older. Bands of rock on the ocean floor on each side of a ridge have like characteristics (age, magnetic polarity, thickness, etc.).
84. Subduction zones are areas where two plates are pushing towards each other, and the denser ocean crust is pushed beneath the (less dense) granite continents.
85. Convergent zones are where two plates of the crust move together. Divergent zones are where two crustal plates move apart.
86. Plate Tectonics is the theory which explains the drifting of continents on large lithospheric plates. This is caused by convection currents in the mantle which release heat produced from the radioactive decay in the earth's core.
87. Earthquake energy travels in waves. P-Waves travel faster than S-Waves; S-Waves don't pass through fluids (like the earth's outer core).
88. Continental crust is thicker and less dense granitic rock; the oceanic crust oceanic crust is more dense and thinner basaltic rock.
89. Isostacy is the principle that as erosion removes material from the continents, they "float" higher in the mantle, maintaining equilibrium in the crust.
90. Rock correlation using index fossils allows the relative dating age of a rock layer to be determined, but not its absolute age (exact # of years).
91. The geologic time scale is based on the fossil record. The Precambrian Eon represents the first 85% of earth's history. Few fossils have been found because life was limited, very simple, and most of the sedimentary rocks have been destroyed.
92. The earth is approximately 4.6 billion years old!
93. An unconformity is a buried erosional surface which represents a gap in the geologic record.
94. Radioactive decay occurs when the nuclei of unstable atoms break down. Radioactive decay used to find the absolute age of a sample.
95. The rate of radioactive decay is measured in terms of half lives. Carbon-14 is used to date materials less than 50,000 years old because it has a short half-life (5700 years).
96. Landscape regions can be divided into mountains, plains, and plateaus. The boundaries between these features are usually well defined by surface features.
97. Uplifting is constantly at battle with the force of erosion. If the rate of uplifting is greater, elevation increases. If erosion is greater, elevation decreases.
98. Subsidence is the sinking of the surface of the earth due to the addition of weight to the surface.
99. Arid climates have steep slopes and angular features; humid climates have smooth, rounded slopes. These differences are caused by different amounts of vegetation.
100. Don't forget to use your Earth Science Reference Tables!!

Labels: 100 Facts For Review

posted by James | 9:46 AM

Name:__________________ Period:____________
Igneous Rocks I
Use your Handy Dandy Earth Science Reference Tables, to answer the following questions. Answer in full sentences where appropriate.
1. What is the texture of granite?

2. What is the grain size of granite?

3. Is granite intrusive or extrusive?

4. Plutonic is also referred to as (intrusive) (extrusive).

5. Estimate the percentage of each mineral in gabbro (look the first “b” in gabbro).
Olivine ___________%
Pyroxene ___________%
Plagioclase feldspar ___________%
Biotite mica ___________%
Amphiboles (hornblende) ___________%

6. List the minerals present in andesite.

7. What is the texture of granite?

8. Name a fine-grained igneous rock with no pyroxene.

9. Name a coarse-grained igneous rock with no pyroxene.

10. Which mineral is present in much greater quantities in peridotite than in gabbro?

11. What is the difference between an igneous rock with a glassy texture and a fine texture? What causes this?

12. Compare rhyolite to basalt (answer in one word only):
a. Which has a lower density?

b. Which has a lighter color?

c. Which has a more mafic composition?

d. Which has a greater percentage of biotite in it?

e. Which contains Quartz?

13. Name a felsic, intrusive rock.

14. Name a light-colored, plutonic igneous rock.

15. Felsic igneous rocks generally have a _____________ color.

16. Mafic igneous rocks generally have a _____________ density.

17. Intrusive igneous rocks have (large) (small) mineral crystals because of (fast) (slow) cooling.

Name:__________________ Period:____________
Igneous Rocks I
Use your Handy Dandy Earth Science Reference Tables, to answer the following questions. Answer in full sentences where appropriate.
1. What is the texture of rhyolite?

2. What is the grain size of rhyolite?

3. Is rhyolite intrusive or extrusive?

4. Plutonic is also referred to as (intrusive) (extrusive).

5. Estimate the percentage of each mineral in rhyolite (look under the “o” in rhyolite).
Potassium feldspar ___________%
Quartz ___________%
Plagioclase feldspar ___________%
Biotite mica ___________%
Amphiboles (hornblende) ___________%

6. List the minerals present in andesite.

7. What is the texture of scoria?

8. Name a fine-grained igneous rock with no quartz.

9. Name a coarse-grained igneous rock with no quartz.

10. Which mineral is present in much greater quantities in peridotite than in gabbro?

11. What is the difference between an igneous rock with a glassy texture and a fine texture? What causes this?

12. Compare rhyolite to basalt (answer in one word only):
a. Which has a higher density?

b. Which has a lighter color?

c. Which has a more felsic composition?

d. Which has a greater percentage of biotite in it?

e. Which contains Olivine?

13. Name a mafic, intrusive rock.

14. Name a light-colored, plutonic igneous rock.

15. Mafic igneous rocks generally have a _____________ color.

16. Felsic igneous rocks generally have a _____________ density.

17. Extrusive igneous rocks have (large) (small) mineral crystals because of (fast) (slow) cooling.

Rock Cycle
Name:________________ Period:_____________
1. As magma cools, it forms _______________ rock by the process of ________________.
2. Igneous rocks can form _______________ , _______________ and _______________ rocks.
3. Sediments form _______________ by the process of ________________ __________________________________________________________ .
4. Sediments form from the process of _____________________________________________ .
5. Sedimentary rocks can form _______________ , _______________ and _______________ rocks.
6. Which process changes igneous rock into metamorphic rock?
7. Which process changes sedimentary rock into igneous rock?
8. Which process changes metamorphic rock into sedimentary rock?
9. Metamorphism involves the addition of _______________ and _______________ to pre-existing rocks.
10. Compaction & cementation of sediments forms _______________ rocks.
11. Subjecting sedimentary rocks to extreme heat & pressure forms _______________ rocks.
12. Solidification of molten materials forms _______________ rocks.
13. Deposition and burial of sediments forms ___________________ rocks.
14. Deposited sediments may be particles of which types of rock?
15. Heat & Pressure acting on igneous rocks forms ___________________ .
16. Solid magma forms ______________________________ .
17. In order to form magma, what must happen to sedimentary, metamorphic or igneous rocks?

18. For weathering & erosion to occur, what process will the rock usually go through first or at the same time?

19. Can sedimentary rock form directly from metamorphic rock? Explain your answer.

Sedimentary
Name:___________ Date:________________ Period:_______

Sedimentary Rocks
1. Define clastic.

2. Define bioclastic.

3. What type of rock is made of particles .05 cm?

4. What type of rock is made of particles .1 cm?

5. What is the chemical composition of bituminous coa1?

6. What rock is formed from biological remains or precipitation?

7. How is dolostone formed?

8. Describe how land-derived sedimentary rocks form?

9. What is the grain size of siltstone?

10. What are evaporites?

11. What is the difference between breccia and conglomerate?

Labels: and Sedimentary, Igneous, Review of Rock cycle

posted by James | 9:26 AM

Tuesday, March 20, 2007

Topics and questions for test

Composition of Matter
Law of definite proportions
Chemical Formulas
Separating Mixtures
Mixtures vs. Compounds

• One of the fundamental observations of modern chemistry, the law of definite proportions states that, in Compounds, the elements combine in proportion with each other, by mass.
• An equivalent statement is the law of constant composition, which states that all samples of a given chemical compound have the same elemental composition
•
• Chemists describe compounds using formula in various formats. For molecules, the formula for the molecular unit is shown. For polymeric materials, such as minerals and many metal oxides, the empirical formula is given, e.g. NaCl for table salt. The order of the elements in molecular and empirical formulas is C, then H and then alphabetical. Trifluoroacetic acid is thus described as C2HF3O2. More descriptive formulas convey structure information, illustrated again with trifluoroacetic acid. CF3CO2H. On the other hand, formulas for inorganic compounds often do not convey structural information, as illustrated by H2SO4 for a molecule that has no H-S bonds. A more descriptive presentation would be O2S(OH)2.
• A chemical compound is a chemical substance consisting of two or more different chemically bonded chemical elements, with a fixed ratio determining the composition. The ratio of each element is usually expressed by chemical formula. For example, water (H2O) is a compound consisting of two hydrogen atoms bonded to an oxygen atom.
• The atoms within a compound can be held together by a variety of interactions, ranging from covalent bonds to electrostatic forces in ionic bonds. A continuum of bond polarities exist between the purely covalent bond (as in H2) and ionic bonds. For example H2O is held together by polar covalent bonds. Sodium chloride is an example of an ionic compound.

Do this
• How do compounds and mixtures differ?

posted by James | 9:05 AM