Earth Science Osat Study Cards

Front 1

Hydrostatic equilibrium

Back 1

the balance between the suns gravitational force and the pressure produced by the hot gases

Front 2

Equinox

Back 2

north pole is at a right angle from the line connecting the earth and the sun—equal periods of light and dark

Front 3

Solar energy

Back 3

located in the sun’s core where nucleosynthesis produces heat energy and photons

Front 4

Moon

Back 4

• Radius 1/4th the size of earth’s radius
• Rocks are like earth’s crust
• Mountains and craters from collisions
• Crust is made of lunar soil
• Core is not as dense as the Earth’s

Front 5

Fission model

Back 5

describes the moon is a piece of earth that split off during the planet’s formation

Front 6

Capture model

Back 6

moon formed elsewhere in the solor system and was captured by earth’s gravitational pull

Front 7

Double-impact model

Back 7

earth and moon formed during the same period of time from the same material

Front 8

4th model

Back 8

asteroid hit earth and formed the moon

Front 9

synchronous rotation

Back 9

orbit is same length as rotation—one side of the moon is always facing the earth

Front 10

Mercury

Back 10

smallest interior planet, atmosphere is not very dense (wide temperature differentials), surface by craters

Front 11

Venus

Back 11

comparible to earth is mass and density, brightest planet, large plains

Front 12

Mars

Back 12

central metallic core, high levels of past volcanic activity

Front 13

Jupiter

Back 13

core of ice and rock, atmosphere of hydrogen and helium, 16 satellites (four largest contain interal activity—one volcanic)

Front 14

Saturn

Back 14

ice and rock core, hydrogen atmosphere, 21 satellites (titan—2nd largest known has own atmosphere, other 6 largest have ice surfaces with past internal activity)

Front 15

Uranus

Back 15

ice and rock core, no evidence of internal activity, spins on it’s side, 5 satellites (evidences of geological activity—valleys, cliffs, mountains)

Front 16

Neptune

Back 16

ice and rock core, 8 satellites (triton—has atmosphere, other seven are unknown)

Front 17

Giant Planet rings

Back 17

• Tidal force exerted on a satellite surpass the Roche limit (point where particle cohesion is no longer possible) and break the satellite into fragments—spreads out and forms a ring
• Unaccreted material left over after the formation of the plants, below the Roche limit, material could not form satellites

Front 18

Kepler’s Laws

Back 18

1: each planet moves in its own elliptical path and that all of these orbits have the sun as their singular focal point
2: a straight line between a planet and the sun sweeps out equal areas in equal time—planets move quickest in the part of their orbit that is closest to the sun
3: the further a planet is from the sun, the loinger its obital period will be

Front 19

Stellar observation

Back 19

Position
o Parallax (apparent shift in position due to the revolution of the earth about the sun) can be used to find the distance to a star

Brightness
o Involves categorization of stars according to their magnitudes

Spectra
o Since stars emit light over a range of wavelengths, viewing a star at different wavelengths
o Spectra analyzes temp of stars—the higher a star’s temperature, the more ionized the gas in its outer layer

Front 20

Binary Star

Back 20

• 50% of stars
• consist of two stars that orbit each other

Front 21

Hertzsprung-Russell diagram

Back 21

• Explores the luminosities and spectral qualities of stars
• Graph (luminosity on vertical, spectral class on horizontal)
• Plot number of stars demonstrates stars fall into narrowly defined regions
• Stars that fall above the diagonal are believed to be larger with low temps and high luminosity (giants and supergiants)
• Stars below the main sequence with high temp and low luminosity are called white dwarfs

Front 22

Stellar evolution

Back 22

• Star is born when a protostar is formed from a collapsing interstellar cloud
• The temp at the center of the protostar rises allowing nucleosynthesis to being
• Nucleosynthesis entails a release of energy—eventuall he star funs out of hydrogen
• If the star is low mass, the disruptions of hydrostatic equilibrium allows the star to contract
• This raises the temperation just outside the core to a point where nucelosynthesis and a different kind of fuel (helium) that produces a carbon nucleus can occur
• Star swells becoming a red giant
• Gravity becomes active again shrinking the stars until the pressure of electrons operate create a white dwarf that will burn out
If the star has a high mass, the depletion of hydrogen creates a supernova

Front 23

Supernova

Back 23

• When a star runs out of hydrogen, it starts to burn helium
• Once helium-burning is complete in a massive star, the mass causes the core temp to rise, enabling the fusion of carbon, then silicon, then iron
• When fusion cycle reaches iron, an iron core begins to form and accumulates over time
• The temp and pressure become too high for electrons to interact with protons
• The core falls and collides with the star’s outer envelope causing an explosion

Front 24

Meteoroid

Back 24

• Small, solid fragment of material in the solar system
• Meteor is a body entering the earth’s atmosphere
• Friction between meteors and upper levels break up meteors into meteorites
• The glow from friction causes shooting stars

Front 25

Asteroid

Back 25

• Small, solid planet that orbits the sun
• Most are between Jupiter and mars
• Atens are asteroids whose orbits lie between the earth and sun
• Apollos are asteroids with orbits that mimic the earth’s
• C-type: compositions similar to that of the sun (dark)
• S-type: compositions of nickel-iron and iron/magnesium-silicates (bright)
• M-type: nickel-iron composition

Front 26

Interstellar medium

Back 26

• Space between planets and stars
• Populated by comets, asteroids, and meteoroids
• Even smaller solid bodies are called interplanetary dust

Front 27

Dark matter

Back 27

• Thought to account for the unseen masses
• May be too small to see, even with telescopes
• Do not interact with photons

Front 28

Newton’s law of gravitation

Back 28

• The force of gravity operates as an attractive force between all bodies in the universe
• Before this, it was believed that two gravitational forces were at work with the universe, that gravity operated differently on earth than it did in space
• F=GMm/D2
o F: gravitational force
o M and m are the masses of two bodies
o D: distance between them
o G: gravitational constant (6.67x10^-11)
• Used to clarify the mechanisms by which kepler’s laws operated

Front 29

Milky way

Back 29

• Spiral galaxy consisting of a central bulging disk which is surrounded by a halo of stars and star clusters
• Rotates about the center
• We are far from the center of the milky way

Front 30

Hubble’s Law

Back 30

• The speed at which a galaxy appears to be moving away from the earth is proportional to its distance from the earth
• v=Hr (v: velocity, r: distance from earth, H: hubble constant)

Front 31

Atmosphere (Earth)

Back 31

78 percent nitrogen

21 percent oxygen

traces of CO2 and argon

majority is located in lowest 10 km

atmosphere shields planet’s surface from harmful cosmic rays and absorbs much of the UV radiation beamed toward the planet from the sun

Front 32

Troposphere

Back 32

surface to 16 km, densest, temps decrease with elevation, most weather happens here

Front 33

Tropopause

Back 33

boundary between the troposphere and the stratosphere

Front 34

Stratosphere

Back 34

16 km to 50 km, temps increase with elevation due to ozone layer absorbing radiation, virtually weather free

Front 35

Stratopause

Back 35

separates stratosphere from mesosphere

Front 36

Mesosphere

Back 36

50km to 80 km, temps decrease with elevation, coldest layer, most meteors enter burn up and break apart

Front 37

Mesopause

Back 37

separates mesosphere from thermosphere

Front 38

Thermosphere

Back 38

80 km to 640 km, warmest layer, temps can reach 1000 C, absorbs high levels of radiation

o Ionosphere: 80 km 550 km, made up of ionized nitrogen and oxygen
o Exosphere: 550 km to 10,000 km, merges with space, satellites orbit earth at this level, made up of hydrogen and helium

Front 39

Ozone layer

Back 39

• Region of the stratosphere with high concentration of ozone particles
• Formed through photolysis—UV light collides with O2 molecules in atmosphere, UV splits O2 apart, O2 combines with free oxygen (O3) is formed
• Ozone molecules absorbs UV rays preventing harmful energy from reaching the earth’s surface

Front 40

Transpiration

Back 40

• Water evaporates into the atmosphere from the leaves or stems of plants
• Plants absorb water into their roots through osmosis
• Water moves upward from the roots to its leaves
• Water escapes though pores in its leaves called stomates
• Water droplets on the leaves evaporate
• Process enables photosynthesis, which releases oxygen into the earth’s atmosphere
• Has a cooler effect

Front 41

Precipitation

Back 41

• Rain is formed in clouds due to condensation
• When drops become too heavy to remain in the cloud (due to decrease in KE), gravity causes them to fall

Front 42

Air Mass

Back 42

• Body of air that exhibits consisten temps and levels of moisture
• Maritime air masses: high levels of moisture
• Continental air masses: drier

Front 43

Depressions

Back 43

• When cold and warm air masses converge
• A warm mass rises over the cold air, cold front and cold air catch up with warm air creating an occluded from and causes pressure to rise

Front 44

Coriolis force

Back 44

• Because of the rotation of the earth
• Northern hemisphere: swing to right
• Southern hemisphere: swing to left

Front 45

Air stability

Back 45

• Heated air rises because its less dense
• As air rises, it expands and becomes cooler
• If the air does not cool as quickly with altitude as rising air does, that air will become coolor and heavier than the surrounding air and descend to original position (stable)
• If the air into which the warm pocket rises becomes colder with increased altitude, the warm air will continue it’s ascent (unstable)
o Form large clouds and precip

Front 46

Clouds

Back 46

• Cirrus: form high in stable atmosphere
• Cumulous: white fluffy ball, the more humid the air—the lower the cloud will form
• Nimbus: low, dark, and formless
• Stratus: cloud of fog
• Cumulonimbus: produced by rapid convection of unstable air, large tall tower (collect of tall towers are squall lines)
• Cirrostratus: ultra-thin with a white tint
• Altocumulus: flattened spheres, clumps, waves, or lines, high altitudes
• Stratocumulus: come together in layers or clumps

Front 47

High pressure

Back 47

warm air is transported by winds to cooler areas at higher latitudes, where the air descends (cool air is heavier than warm air)

Front 48

Low pressure

Back 48

descended air is moved by surface winds where it encounters colder air, air rises

Front 49

Global warming

Back 49

• Greenhouse effect keeps temps on the planet 33 degrees higher
• Increase of CO2 and methane from burning fossil fuels like coal and oil and releasing them into the atmosphere
• Increasing deforestation has affected the number of photosynthesis plants

Front 50

Ozone depletion

Back 50

Occurs when the balance between creation and destruction of ozone particles in the stratosphere is tipped toward destruction

Front 51

El Nino

Back 51

• The unusual warming of surface waters near the equatorial coast of south America
• Occurs during the winter every 2 to 7 years lasting a few weeks to months
• Can cause rains, violent winds, drought, high temps
• Caused by the reversal of the atmospheric pressure on the eastern and western sides of the pacific
• This reversal causes a wave of warm water to flow eastward and sea levels to fall on western side

Front 52

Rock

Back 52

• Cannot be created or destroyed
• Undergo a series of changes
• Naturally formed inorganic object composed of one or more of the minerals found in the earth’s crust
• Rocks are heterogeneous

Front 53

Rock cycle

Back 53

o Process where the materials that make up the earth transition through the 3 types of rock
o Plate tectonics and the water cycle are driving forces behind the rock cycle—they force rocks and minerals out of equilibrium and force them to adjust to different external conditions
o Rock beneath surface melt into magma, magma erupts volcanoes or remains inside the earth, magma cools, forming igneous rocks, on the surface igneous rocks experience weathering and erosion which break them down and distribute across the surface, they form layers and become sedimentary, which are transformed to metamorphic rocks or melted down to magma

Front 54

Igneous Formation

Back 54

o Can be formed from sedimentary, metamorphic rocks, or other igneous rocks
o Rocks are pushed under surface and melt to magma which is released through volcanic process
o Magma cools, forming grainy igneous rocks (extrusive)
o Cooling process is rapid—can be so quick that crystals do not form
o Intrusive igneous rocks is magma cooled beneath the surface—these cool more slowly resulting in coarse-grained texture

Front 55

Sedimentary Formation

Back 55

o Formed when rocks at the surface experience weathering and erosion
o Fragmented material accumulates in layers, top layers burying the materials beneath
o Pressure exerted by the topmost layers causes lower layers to compact creating solid sedimentary rock--lithification

Front 56

Metamorphic Formation

Back 56

o Are igneous or sedimentary that have “morphed” into another kind of rock
o High temps and levels of pressure change rocks physically and/or chemically
o Regional metamorphism: a large band of metamorphic activity
o Contact metamorphism: native rock comes in contact with high-heat igneous magma

Front 57

Role of water

Back 57

• It wears down rocks
• It contributes to the dissolution of rocks and minerals as acidic soil water
• It carries ions and rock fragments to basins where they will be compressed into sedimentary rock
• Plays a role in metamorphic processes that lccur under water

Front 58

Petrogenesis

Back 58

rocks are classified according to their origin, usually more favorable rock-identification technique than petrography

Front 59

Petrography

Back 59

rocks are described and idteified based on several physical characteristics

Front 60

Sedimentary Solid rocks

Back 60

Water is expelled from pores and pores are filled with solid rock

Front 61

Sedimentary Clastic Rocks

Back 61

o Formed only from fragments of other rocks
o Conglomerates: compaction of cementation and gravel
o Sandstones: small diameter fragments
o Shale: smaller than 0.0625 mm
• Half of sed rocks are shale

Front 62

Sedimentary Precipitated rocks

Back 62

o Formed through the evaporation of the liquid in a solution

Front 63

Sedimentary Organic rocks

Back 63

o Formed from the remains of plant and animal organisms
o Limestone is most abundant
o Coal

Front 64

Sedimentary Stratification

Back 64

o Strata: horizontal layers of rock
• Thicker than 1 cm—bed
• Thinner than 1 cm--Laminae
o Occurs due to variations in the volume, mineral compsotion, or color of sediment
o Varves: repitition of two layers

Front 65

Continental sediment deposition

Back 65

o Alluvial fans: sediment is quickly dumped into basin and spreads out into fan shape
o Wind is most effect in deposition

Front 66

Sedimentary Color

Back 66

o Red indicates erosion, weathering or iron-bearing minerals
o Organic rocks such as coal exhibit gray or black coloration

Front 67

Igneous Rocks

Back 67

• Felsic igneous rocks
o Granite: light in color, coarse to fine grained
o Rhyolite: fine grained, glassy
o Pumice: high concentration of gasses when cooling

• Mafic igneous rocks
o Gabbro: Coarse grained and dark colored, magnetic
o Basalt: Most common volcanic rock, very fine grained

Front 68

Intermediate rocks

Back 68

• Diorite: fine to coarse grained, gray color
• Andesite: fine grained, black or gray

Front 69

Metamorphic rocks

Back 69

• Foliation
o Low grade: slate
o Intermediate grade: sandstone
o High-grade: Gneiss

Front 70

Minerals

Back 70

• Naturally occurring, inorganic, solid physical substance
• Some minerals are elements, but many are compounds

Front 71

Mineral Classification

Back 71

Color
Luster
Streak
Hardness
Cleavage
Fracture
Specific Gravity
Tenacity
Habit

Front 72

Luster

Back 72

difference in opacity and translucency, metallic lusters are opaque, nonmetallic are dull, silky, pearly

Front 73

Hardness

Back 73

Mohs’ scratch test (talc) softest to (diamond) hardest, accurate to the half-increment

Front 74

Fracture

Back 74

imperfect or nonexistent cleavage
• Conchoidal: shell like pattern, concentric rings spreading outward from the break
• Irregular: rough, uneven surface
• Hackly: line of fracture with sharp, jagged edges

Front 75

Specific gravity

Back 75

density

Front 76

Tenacity

Back 76

the way a mineral respondes to the application of forces such as cutting, bending, or crushing
• Brittle: fracters under a forceful blow
• Elastic: returns to orginal shape
• Flexible: will bend/not break, but will not return to shape
• Malleable: can be reshaped without fracturing—flatted into sheets
• Ductile: drawn into thin strands without breaking
• Sectile: can be slided into thin sheets, but cannot withstand the force of a blow

Front 77

Habit

Back 77

growth pattern of a mineral crystal, pressure, temp and chemical conditions influence habit
• Equant: its sides are of nearly equal length in all directions
• Bladed: long, flat areas that are reminiscent of knife blades
• Plumose: series of feathery scales
• Micaceous: thin, flat sheets that can be flaked or peeled
• Prismatic: elongated