Earth Science Study Guide PDF

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Earth Science Final Exam Study Guide General Principles Principles Energy can change type or pass between objects, but not be created or destroyed. Forces make things move. Matter is made of atoms. Cause-effect statements Force causes a change in motion (speeding up, slowing down, changing direction). Potential energy turning into kinetic energy makes things move faster. Potential energy or kinetic energy turning into heat causes things to get warmer. Hotter causes faster motion of atoms. Definitions Force – any push or pull on an object Kinetic energy – energy of motion Potential energy – if an object will move if it is released Heat – internal kinetic energy due to motion of individual atoms Chapter 1-Properties of science Good scientific investigation should have the following characteristics 1. Scientific explanations are provisional 2. Scientific explanations should be predictable and testable 3. Scientific explanations are based on observations 4. Scientific explanations identify a natural cause Chapter 2 Part I – Solar System Principles Gravity acts on all objects. Cause-effect statements Gravity causes planet to orbit the Sun. Closer to the Sun causes hotter. Getting closer to the Sun causes a planet to move faster. Closer to the Sun causes Terrestrial planets. Closer to the Sun causes shorter orbital period. Spinning of Earth causes days. TiltofEarth’saxiscausesseasons. Definitions Gravity-force pulling towards a massive object Terrestrial planet-small rocky planet close to the Sun Jovian planet-large gassy planet far from the Sun Geocentric model-the Sun, moon, planets, and stars orbit Earth Heliocentric model-Earth and the planet orbit the Sun 1

Retrograde motion-apparent backwards motion of a planet during part of the year Period of orbit-time for one full orbit Kepler’s1st law-orbits are ellipses Kepler’s2nd law-planets move faster when they are closer to the Sun Kepler’s3rd law-the period of a planet depends on the radius of its orbit Chapter 2 Part II– The rest of the universe Principles Blackbody radiation Light by atomic transitions Cause-effect statements In blackbody radiation, hotter causes brighter and bluer light. In atomic transitions, different types of materials cause a different set of colors of light. Motion of a star away from Earth causes a redshift. In the Big Bang model, an explosion causes expansion causes cooling and redshifts. Definitions Blackbody radiation-a mixture of all colors of light emitted from a hot object Atomic transitions-atoms release light when they transition from a high energy level to a lower energy level, giving off a few specific colors of light Big Bang Model-an explosion in the past led to the formation of the current universe Absolute magnitude-how bright a star is Apparent magnitude-how bright a star appears to be from Earth Doppler effect-waves (light) from a moving source have shifted wavelengths Redshift-shifting to longer wavelength from a star moving away Cosmic microwave background-blackbody radiation filling space leftover from the Big Bang Main-sequence star-a typical star that forms by the same process as most stars Chapter 4 – Plate tectonics Principles Earth’scrustisbrokenintoplates,whichfloatonthemantleandarefreetomove. Evidence for motion of plate Cause-effect statements Difference of temperature within a fluid causes convection. Heating causes expansion causes lower density causes rising causes convection. Mantle convection causes plates to move. A divergent boundary causes a mid-ocean ridge and a rift. Divergent boundaries cause creation of new crust at the boundary. A convergent boundary causes a trench and a volcanic arc. Convergent boundaries cause destruction of old crust. All plate boundaries cause earthquakes. Definitions Continental drift-theory that continents move over time 2

Plate tectonics-theory that plates of crust move over time Plate-apieceofEarth’scrust Convection-circulatory flow of a fluid caused by a difference in temperature Divergent plate boundary-where two plates move apart Convergent plate boundary-where two plates collide Transform plate boundary-where two plates slide past each other Mid-ocean ridge-long double ridge on either side of a divergent plate boundary Rift-deep valley in the middle of a mid-ocean ridge Subduction-one plate moving down into the mantle beneath another plate at a convergent boundary Continental volcanic arc-a line of volcanoes near a convergent plate boundary on the continental side Island arc-a line of volcanic islands near a convergent plate boundary Trench-a very deep valley in the ocean at a convergent plate boundary Earthquake-a wave travelling through the Earth Chapter 5 – Earthquakes Principles Motion at plate boundaries causes earthquakes. Cause-effect statements Motion at plate boundaries causes earthquakes. Elastic deformation of a plate causes storage of potential energy. Release of stored elastic potential energy causes earthquake. Further distance from epicenter causes larger difference in time between arrival of P and S waves. Stiffer material causes faster wave speed. Change in wave speed causes reflection and refraction. Terms Earthquake-a wave travelling through Earth rocks Fault-aplanewhereEarth’scrustisbroken Focus-the point on the fault where the earthquake originates Epicenter-thepointonEarth’ssurfacedirectlyabovethefocus Elastic deformation-change in shape (bending or stretching) of a material in which the material returns to its original shape when released Plastic flow-change in shape of a material in which the material does not return to its original shape when released P waves-longitudinalearthquakewavesthattravelathighspeedthroughEarth’sinterior S waves-transverseearthquakewavesthattravelslowerthroughEarth’sinterior Surface waves-earthquakewavesthattravelonlyalongEarth’ssurface Seismograph-a device used to measure motion during an earthquake Crust-rigid thin outer layer of Earth Mantle-semisolid layer of Earth under the crust Outer core-liquid layer of Earth under the mantle Inner core-solid central layer of Earth 3

Reflection-a wave bounces off of a material Refraction-a wave bends as it goes into a material with a different wave speed Chapter 6 – Volcanoes Principles Volcanoes result from plate tectonics. Cause-effect statements At convergent boundaries, mixing of hot rocks with water causes melting. At divergent boundaries and hot spots, decrease in pressure on hot rocks causes melting. Above convergent boundaries, heating of rocks by nearby magma causes melting. Convergent boundaries cause magma with volatiles. Volatiles cause explosive eruptions. Convergent boundaries cause stratovolcanoes. Divergent boundaries and hot spots cause shield volcanoes. Hotter causes lower viscosity. Higher silica content (lighter rocks) causes higher viscosity. Terms Hot spot-a location where volcanoes occur that is not at a plate boundary Viscosity-resistance of a liquid to flow Volatiles-gases (mostly water vapor) dissolved in magma Basaltic magma-magma made of dark minerals that is hot and low viscosity Andesitic magma-magma made of light minerals that is medium viscosity and usually contains volatiles Rhyolitic magma-relatively cool, high viscosity magma made of light minerals Shield volcano-a large, shield shaped (broad base, not steep) volcano that erupts basaltic magma Cinder cone-a small steep volcanic structure made of loose grains of igneous rocks (cinders) that forms due to eruptions of rhyolitic magma Stratovolcano-a tall steep volcano made of a mixture of solid igneous rocks and cinders that forms due to eruptions of andesitic magma Island arc-a line of islands at a convergent boundary made up of composite cones Continental volcanic arc-a line of composite cones along a continent edge at a convergent boundary Chapter 7 Part I – Minerals Principles Crystalline structure and chemical composition determine mineral properties The rule of 8-atoms bond in order to make it so that their outer shell of electrons is full with 8 electrons (2 electrons if the outer shell is the 1st shell) Cause-effect statements Theshapeofamineral’scrystallatticecausesitscleavage. Thestrengthofamineral’schemicalbondscausesitshardness. Amineral’scompositioncausesitschemicalactivity.

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Definitions Mineral-a naturally occurring, inorganic, solid, with a well-defined chemical composition, and a crystal lattice structure Crystal lattice structure-atoms are located in a repeating pattern Chemical composition-the elements that make up a mineral Organic-part of an organism or made by an organism Ion-an atom with one extra electron or one missing electron Isotope-an atom with a different number of neutrons Color-a mineral property Luster-metallic or nonmetallic appearance Streak-color of powdered mineral Habit-the shape that a mineral naturally forms in Hardness-resistance of a mineral to scratching Cleavage-breaking of a mineral along smooth planes Density-mass per volume Chapter 7 Part II –Rocks Principles Phases of matter: Any liquid or gas will solidify if you cool it enough. Any solid will melt if you heat it enough. Cause-effect statements Crystallization of magma causes igneous rocks. Cooling underground causes slow cooling causes coarse grains. Cooling on the surface causes fast cooling causes fine grains. Solidification while bubbles are present causes vesicles. Crystallization of dark minerals at higher temperature than light minerals causes dark igneousrocksdeepundergroundandlightigneousrocksonthesurface.(Bowen’s reaction series) Breaking a rock (mechanical weathering) causes clastic sediment. Expansion of water when it freezes causes frost wedging. Chemical reactions with a rock (i.e. dissolving) cause chemical weathering cause chemical sediment. Compaction (often with a small amount of cement) causes clastic sedimentary rocks. Deposition of chemical sediment causes chemical sedimentary rocks. Recrystallization causes change in mineral grain size, shape, or composition (metamorphic rocks). Definitions Rock – any naturally occurring solid, usually an aggregate of different mineral types or other materials Magma – liquid melted rock Igneous rock – a rock that forms when magma crystallizes Coarse grained – igneous rock contains mineral grains that are large enough to see with the naked eye Fine grained – igneous rock contains mineral grains that are too small to see with the naked eye 5

Glassy – igneous rock with a texture like glass Vesicles-air bubbles in a glassy igneous rock Porphyritic – igneous rock containing large mineral grains surrounded by smaller mineral grains Intrusive – crystallizing underground Extrusive-crystallizing on the surface Mechanical weathering- breaking a rock into smaller pieces Frost wedging-breaking a rock when water in cracks freezes and expands Chemical weathering-breaking down a rock by a chemical reaction, such as dissolving Clastic sediment-broken pieces of rock Clastic sedimentary rock-a rock made mostly of clastic sediment Chemical sediment-dissolved minerals Chemical sedimentary rock-a rock made mostly of deposited chemical sediment Biochemical sedimentary rock-a rock made mostly of organic material Metamorphic rock-a rock that has its mineral structure or composition changed from a previous igneous or sedimentary rock by the application of heat and/or pressure Foliated texture-minerals grains in a metamorphic rock are elongated and aligned Chapter 8 – Relative and radioactive dating Principles Locations and arrangements of rocks show relative ages. Radioactive decay inside rock can be used to determine the absolute ages of the rock. Processes An elapsed time of 1 half-life causes the amount of parent isotope to decrease by half. (see following table) Parent isotope 100% 50% 25% 12.5%

Daughter isotope 0% 50% 75% 87.5%

Time 0 1 half-life 2 half-lives 3 half-lives

The parent isotope column is divided by 2 in each row. The time column had 1 half-life added in each row. The daughter isotope is the total amount minus the parent isotope. Terms Principle of superposition-younger sedimentary rocks form on top of older sedimentary rocks Principle of cross-cutting-any feature (rock or fault) that cuts through another layer of rocks is younger than the layer that it cuts Inclusions-broken pieces of rock that are surrounded by a layer of other rocks Principle of inclusions-inclusions are older than the rocks that surround them Principle of original horizontality-sedimentary rocks that are tilted are older than sedimentary rocks that are horizontal Unconformities-an eroded surface that separates two rock layers Principle of unconformities-rocks below an unconformity are older than rocks above the unconformity 6

Half-life-amount of time for half of the parent isotope to decay Chapter 11 – Runoff Principles Gravity causes water to flow downhill. Rivers shape the landforms around them by eroding and depositing. Cause-effect statements Gravity causes water to flow downhill. Steeper causes faster flow. Lower viscosity causes faster flow. Deeperwatercausesfasterflowontheriver’ssurface. Faster flow causes more erosion. A fast flow that slows down causes deposition. Definitions Water cycle-water continually evaporates, condenses, precipitates, and runoff Evaporation-turning liquid into gas Condensation-turning gas into liquid Precipitation-water falling as rain or snow Runoff-wateronEarth’ssurfaceflowinginstreamsorrivers Viscosity-resistance of water to flow, fluid friction Turbulence-chaotic, mixing flow of water Head of river-where the river first starts Mouth of river-where the river empties into a larger body of water (larger river, lake, ocean) Gradient-steepness of land Dissolved load-minerals dissolved in a river Suspended load-sand grains or mud lifted and carried by a river Bed load-sediment that slides along the river bed Downcutting-erosion by a river that forms a canyon Floodplain-flat plain around a river Lateral erosion-a meandering river widening its valley by eroding the valley walls Meander-a back and forth flowing river Cut bank-a steep eroded bank on the outside of a meander Point bar-a sandy bank on the inside of a meander Oxbow lake-lake formed by an abandoned meander Delta-land formed from sediment deposited at the mouth of a river Chapter 14 Part I (14.1-14.4) – Atmosphere structure and temperature Principles Absorption of light causes heating. Cause-effect statements Lighter color causes higher albedo (less absorption). In blackbody radiation, hotter causes shorter wavelength. In atomic transitions, different type of atom causes absorption of different wavelengths of 7

light. Higher altitude causes lower pressure. In the troposphere, higher altitude causes colder. Greenhouse effect: 1. Visible light emitted by the Sun is not absorbed by the atmosphere. 2. Light from the Sun warms Earth. 3. Infrared light emitted by the Earth is absorbed by the atmosphere. 4. The atmosphere emits infrared light, some of which goes back towards the Earth. 5. Absorption by Earth of infrared light emitted by the atmosphere causes extra warming of Earth. Absorption by the atmosphere of infrared light emitted by the Earth but not visible light emitted by the Sun causes the greenhouse effect. An increase in greenhouse gases (carbon dioxide) in the atmosphere causes global warming. Scattering of blue light by the atmosphere causes blue skies and red sunsets. Terms Albedo-reflectivity of a material Troposphere-lowest layer of the atmosphere Stratosphere-2nd layer of the atmosphere, containing the ozone layer Mesosphere-3rd layer of the atmosphere Thermosphere-top layer of the atmosphere Greenhouse effect-extra warming of Earth because of the atmosphere Global warming-an enhancement of the greenhouse effect because of an increase in carbon dioxide in the atmosphere Chapter 14 Part II (14.5-14.7) – Humidity and clouds Principles Water can change state from liquid to gas (evaporation) or from gas to liquid (condensation). Processes Rising air causes expansion causes cooling. Cooling causes higher relative humidity. Relative humidity ≥ 100% causes condensation. The previous three cause-effect statements can be combined into a common cause-effect chain: Rising air causes cooling causes increased relative humidity causes condensation. Hotter causes higher saturated amount of water vapor. Hotter causes more evaporation. Relative humidity < 100% causes evaporation. Cooling to a temperature below the dew point causes condensation. Adding water vapor causes higher humidity. Condensation causes release of latent heat causes warming of the surroundings.

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Terms Evaporation-liquid turning into gas Condensation-gas turning into liquid Relative Humidity-the ratio of the current amount of water vapor to the maximum amount of water vapor that the air can hold (  ) 𝑅𝑒𝑙𝑎𝑡𝑖𝑣𝑒ℎ𝑢𝑚𝑖𝑑𝑖𝑡𝑦 =  ∗ 100% Saturated amount of vapor-the maximum amount of water vapor that the air can hold at a given temperature Dew point-the temperature at which condensation starts, i.e. the temperature at which relative humidity=100% Latent heat-energy that is absorbed (evaporation, melting) or released (condensation, freezing) during a phase change Environmental lapse rate-the rate at which temperature decreases with altitude for stationary air Dry adiabatic lapse rate- the rate at which temperature decreases with altitude for rising air Wet adiabatic lapse rate- the rate at which temperature decreases with altitude for rising and condensing air Chapter 14 Part III and Chapter 16 Part I (14.8-14.9 and 16.1-16.3) – Wind Principles Air moves if there is a force on it, usually due to a pressure difference. Cause-effect statements Difference in pressure causes wind to blow from high pressure to low pressure. In a sealed container, hotter causes higher pressure. Expansion causes lower pressure. More gas causes higher pressure. If not in a sealed container, hotter causes rising air causes low pressure. Coriolis effect causes wind to deflect to the right in the Northern Hemisphere. Location near the ocean causes higher heat capacity causes more stable temperature. Terms Pressure-air pushes outward in all direction on its surroundings Pressure gradient-two different locations have different pressures Wind-moving air Heat capacity-amount of energy needed to increase the temperature of a material Sea breeze-a cool breeze flowing from the ocean to the land during the day Land breeze-a breeze flowing from the land to the ocean at night Convection-circular flow of a fluid due to a difference in temperature Coriolis effect-free moving objects on the rotating Earth appear to deflect instead of move in a straight path Cyclone-a region with rising air and low pressure Anticyclone-a region with sinking air and high pressure Chapter 16 (16.1-16.3)-Climates Principles Global patterns of temperature, pressure, and precipitation are closely related. 9

Processes Hot air causes rising causes low pressure causes wind. (global convection) Hot air causes rising causes cooling causes condensation and precipitation. Sinking air causes heating does not cause precipitation. Terms Convection-circular flow due to a difference in temperature Prevailing winds-the dominant direction of wind in a region Trade winds-prevaling winds that blow East to West between the Tropics and the equator Westerlies-prevailing winds that blow West to East between the Tropics and the Arctic Circle Polar easterlies-prevailing winds that blow West to West between the Arctic Circle and the North Pole Rainshadow desert-a dry region behind mountains formed with wind blows over the mountains

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