AMAZING EARTH SCIENCE FACTS
Scientific Investigation Facts
1. Density = mass/ volume. The S.I. units for density are grams/cm3 or g/ml
2. Volume for irregularly shaped objects is found by water displacement.
3. Warm (air, water, magma) rises because it is less dense. Cold (air, water, magma) sinks.
4. As pressure increases so does density.
5. Water is most dense in the liquid state or phase. Density of water is 1 g/ml
6. The same substance has the same density.
7. As mass increases so does the volume.
8. A hypothesis is a prediction about a problem that can be tested.
9. A variable is a changeable factor in an experiment.
10. An independent variable is something that the scientist changes.
11. A dependent variable is something that changes because of what is being tested.
12. Constants are factors that are the same.
13. Any valid scientific theory has passed tests designed to invalidate it.
14. There can be more than one expolanation for any phenomena.
Mapping Facts
1. The altitude of Polaris equals your latitude.
2. Latitude lines go East and West but are measured North or South of the equator.
3. Longitude lines go North and South but are measured East or West of the Prime Meridian.
4. Lines of latitude are called parallels.
5. Lines of longitude are called meridians.
6. The Prime Meridiamn is zero degrees longitude.
7. The equator is zero degrees latitude.
8. The international Date Line is 180 degrees longitude.
9. The magnetic North Pole is not located in the same place as the geographic North Pole.
10. Hachure lines on a topographic map indicate a depression or a valley.
11. Contour lines are marked at given interval, in feet. The closer together the contour lines are, the steeper the slope.
12. Contour lines form V's and point upstream of rivers and creeks.
Geology of The Earth Facts
1. The Earth consists of a solid inner core made of Fe and Ni (iron and nickel); a liquid outer core made of Fe and Ni
(iron and nickel); a plastic-like mantle made of Si, O, Fe, and Ni (silicon, oxygen, iron, and nickel); and a thin rocky
crust made of Si and O (silicon and oxygen).
2. The lithosphere is composed of the crust and upper mantle.
3. Ocean crust is thinner, younger, and denser than continental crust.
4. Ocean crust is made of basaltic rock.
5. Convection currents move tectonic plates.
6. Hot material rises, cools, becomes more dense and sinks.
7. Convergent boundaries are colliding plates which cause folded or thrust faulted mountains, subduction zones (volcanoes
and trenches), and reverse faults.
8. Divergent boundaries are dividing plates and cause sea-floor spreading, mid-ocean ridges, rift valleys, and volcanoes.
Normal faults are produced from this movement.
9. Earthquakes can result with any plate movement.
10. Hot spots are not related to plate movement.
11. A fault is a break or a crack in the Earth's crust where movement has occurred.
12. The Appalachian Mountains are folded mountains.
13. Volcanic activity is associated with subduction, rifting, or sea-floor spreading.
14. An ocean plate will always sink under a continental plate because it is more dense.
15. Three seismic (3) stations are needed to find the epicenter of an earthquake.
16.P waves (Primary waves) travel the fastest and reach the seismic station first.
17. P waves travel through solids and liquids.
18. P waves slow down and bend when they hit the the liquid outer core.
19. S waves (Surface waves)cause the most damage.
20. S waves do not travel through liquids.
Weathering and Erosion
1. Weathering is the process that breaks down rocks by water, air, or organisms.
2. Chemical weathering occurs in warm, humid climates.
3. The chemical composition of the rock is actually changed during chermical weathering.
4. Mechanical weathering occurs in cold climates.
5. Ice wedging is an example of mechanical weathering.
6. Erosion is the carrying away or transporting of earth materials. The eroded earth materials are being transported by
moving water, ice, or wind. Gravity causes all of these things to happen.
7. Streams and moving water are the major agents of erosion.
8. Deposition is the dropping out or settling out of sediments.
9. Unconformities are missing rock layers that are caused by erosion.
10. High erosion causes high relief areas.
11. high deposition causes low relief areas.
12. Large particles settle out first.
13. Sediments range in size from largest to smallest when they settle Ex. breccia, sand, silt, and clay.
14. As particle size increases, permeability (the ability to transport water) increases.
15. Soil evolution starts with the weathering of bedrock.
16. Organic material must be present in order to have soil.
17. A soil profile consists of 3 horizons: A - Top soil (humus - least evolved); B - less humus, leaching, from A; and C -
weathered rock, bedrock.
18. Karst topography has caves and sinkholes produced by acidic groundwater dissolving limestone.
19. The Valley and Ridge Province is famous for Karst topography.
20. Groundwater layers, from the surface downward, include the zone of aeration, water table, and zone of saturation.
21. An aquifer is a layer of rock thast transports groundwater freely.
22. A spring is an area where the water table reaches land's surface.
23. The hydrologic cycle (water cycle) includes the following processes: (1) evaporation, (2) condensation,
(3) precipitation, (4) runoff, and (5) infiltration.
24. The Coastal Plain is the flattest area underlain by all types of sediments produced by the erosion of the Appalachian
Mountains.
25. Fossils are abundant in the Coastal Plain.
26. The Piedmont region is underlain by igneous and metamoprphic rocks produced by ancient volcanoes.
27. The Piedmont region is separated by a fall line from the Coastal Plain.
28. The Blue Ridge is the oldest region in the state of Virginia.
29. The Valley and Ridge Province has long parallel ridges composed of folded and faulted rocks that occurred during the
collision of Africa and North America during the Paleozoic era. Karst topography and fossils are abundant here.
30. The Appalachian Mountain chain is underlian by sedimentary rocks. Coal eresources are found here and fossils are present.
31. Coal evolution: begins as peat which is the softest form of coal. Next is lignite, then bituminous, and finally, anthracite, which
is the hardest form of coal.
32. Minerals are found in nature.
33. Minerals have a definite chemical composition and structure.
34. Mineral properties depend on their atomic structure.
35. Minerals can be formed from magma or from solutions.
36. Ores are useful and are mined for profit.
37. Igneous rocks are classified by their composition and structure.
38. Igneous rocks are formed by the cooling of magma or lava.
39. If igneous rocks are cooled extrusively, (outside the Earth's crust) they cool very quickly.
40.The texture of extrusive rocks includes small mineral grains, glassy and some have air holes. Examples include pumice,
obsidian, and basalt.
41. If igneous rocks are cooled intrusively (inside the Earth's crust) they cool very slowly.
42. The texture of intrusive rocks includes coarse or large mineral grains. Examples of intrusive rock includes granite.
43. Felsic colored rocks are light colored, while mafic rocks are dark colored.
44. Ultramafic rocks may contain olivine and augite and are very dark in color.
45. Metamorphic rocks are formed from heat and pressure.
46. Metamorphic rocks are either foliated (banded) or non foliated.
47. Examples of foliated metamorphic rocks include slate, schist, and gneiss. Non foliated rocks include marble and
quartzite.
48. Limestone becomes the metamorphic rock marble, and sandstone becomes the metamorphic rock quartzite. Shale
becomes the metamorphic rock slate.
49. Sedimentary rocks are formed from rock fragments, orgzanic material, or chemical precipitation.
50. Sedmientary rocks are found in flat layers or strata. Fossils are found inthese layers of rock.
51. Fossils found in the sedimentary rocks help to identify the age of the rocks.
52. Sedimentary rocks are classified as clastic (formed from other broken down rocks), or nonclastic (formed from either
organic material or chemical precipitation).
53. Examples of clastic sedimentary rocks include conglomerate, breccia, sandstone, and shale.
54. Limestone is formed either organically or chemically.
55. Virginia resources include limestone, coal, and gravel.
56. Renewable resources can be replaced by nature at a rate close to the rate at which they are used.
57. Renewable resources include vegetation, water, and soil.
58. Nonrenewable resources can be replaced very slowly, or not at all. These include coal, oil, and minerals.
59. The Earth's water supply is renewable, but it is also finite.
60. A fossil is the remians, impressions, or just evidence of a former existence of life preserved in rock.
61. Virginia's fossils are mostly marine and are from all eras in history.
62. The Law of Superposition states that the oldest rocks are found at the bottom of strata (layers of rock), and the
youngest layers are found on top of the strata.
63. The Law of Cross-Cutting Relationships atates that an igneous intrusion is younger than the layers it cuts across.
64. Fossils, superposition, and cross-cutting are used to determine the relative age of rocks.
65. Relative age involves placing events in sequence without assigning an exact numerical age.
66. Absolute time gives a numerical age to an event.
67. Radioactive decay or half-life is used to determine the absolute age of rocks.
68. Uranium dating is used to find the ages of human artifacts.
69. The Earth is approximately 4.6 billion years old.
Oceanography Facts
1. There are two high tides and two low tides ina 24 hour period (one day).
2. There is only one high tide and one low tide in a 24 hour period in a gulf. (The Gulf of Mexico is an example).
3. Tides are caused by the gravitational pull of the Earth and the Moon.
4. Currents move from cold to warm areas.
5. Upwelling brings cold, nutrient rich water from the bottom of the ocean to the surface. This is rich in biological activity.
6. Estuaries are areas where salt water mixes with fresh water. An example of this is The Chesapeake Bay.
7. Sea level rises when ice caps melt.
8. Cyanobacteria was responsible for the first oxygen on Earth.
9. Presently, blue-green algae is an important source of oxygen.
10. The ocean is the largest reservoir of heat at the Earth's surface. It drives the weather of the Earth.
11. All water from rivers, lakes, and streams want to travel to the ocean.
Atmosphere and Meteorology Facts
1. The early atmosphere was mostly carbon dio9xide and oxygen.
2. The Earth's atmosphere is 21% oxygen, 78% nitrogen, and 1% trace gases.
3. Human activities, such as burning fossil fuels has increased carbon dioxide levels.
4. High carbon dioxide levels produce the Greenhouse Effect.
5. Chlorofluorocarbons (CFCs) are decreasing the ozone levels of the upper atmosphere.
6. Areas near the equator receive the most direct radiation from the sun.
7. Clouds form when air is at or below its dew point and condensation nucklei are present.
8. The Coriolis Effect causes deflrctions of the winds in our atmosphere due to rotation of the Earth.
9. The Coriolois Effect also causes deflectioons of our oceans due to rotation of the Earth.
10. A psychrometer measure humidity in the air.
11. A barometer measures air pressure.
12. An anemometer measures wind speed.
13. Highs are warm and dry. Lows are cool and wet.
14. Wind is due to unequal cooling that causes air pressure differences.
15. Winds blow from highs to lows.
16. Cold fronts move quickly and produce rain at the front.
17. Warm fronts move slowly and produce miles and miles of clouds.
18. The highest pressure is found at sea level.
19. High pressure systems move clockwise and outward.
20. Low pressure systems move counter-clockwise and inward.
21. Weather in the United States is dominated by the prevailing westerlies.
22. Weather and winds move from west to east.
23. The summer solstice is June 21st (the longest daylight hours).
24. The winter solstice is December 21st (the shortest daylight hours).
25. Solstices occur when the sun is at its northenmost or southernmost point.
26. Equinoxes occur when the sun is directly over the equator.
27. The spring equinox is March 21st and the autumnal (fall) equinox is September 21st.
28. An equinox has 12 hours of daylight and 12 hours of night.
Astronomy Facts
1. The Earth rotates from west to east once every 24 hours.
2. The Earth revolves around the sun counter-clockwise, once every 365.25 days.
3. The Earth is the third planet from the sun.
4. The Moon has phases because of reflected sunlight and the angle at whic we view it.
5. Foucault's Pendulum and the Coriolis Effect are proof that the Earth rotates.
6. Parallax and seasonal constellations prove that the Earth revolves.
7. Planets are grouped into two groups; the inner planets are called the Terrestrial planets and the outer planets are called
the Gas Giants.
8. Comets are known as dirty snowballs in spce and originate in the Oort cloud.
9. A comet's tail always points away from the sun. The tail of a comet is the result of the solar wind.
10. The coma of a comet is due to the radiation of the sun.
11. Asteroids are rocky or metallic iron objects with origins between Mars and Jupiter.
12. An astronomical unit (AU) measures the distance of the Earth and Sun.
14. We measure planets in astronomical units as well.
15. A light year is the distance light travels in one year.
16. We measure the distance of stars and galaxies in light years.
17. Apollo 11 was the first manned landing on the moon.
18. Neil Armstrong was the first American man to walk on the Moon.
19. The Big Bang explains the origin of the universe.
20. The universe began as a dense sphere and expanded and condensed into galaxies.
21. The Solar Nebulae Theory explains that the planets formed from the condensing of our sun or solar nebulae.
22. The life cycle of our sun is: Nebulae, protostar, main sequence star, red giant, white dwarf, and black dwarf, in that
order.
23. Our sun is currently a medium, main sequence, yellow star.
24. Black holes are the death stages of most stars.. In other wirds,the remains of most dead stars are what forms black
holes.
25. In order for a star to become a black hole after it has died, it must have been as big as at least 8 solar masses.
26. Earth is located in the Milky Way galaxy.
27. The Milky Way galaxy is a spiral galaxy.
28. Galaxies are classified as either elliptical, spiral, or irregular.
29. The Hubble Sopace Telescope has improved our knowledge and understanding of the universe in which we live.
30. Red shifts indicate a celestial object is moving away from us.
31. Blue shifting indicates that a celestial object is moving toward us.
32. Red shifts indicate that the universe is expanding outward.
33. Red shifting is used to support the BIg Bang Theory.