Term
|
Definition
| theory that the sun and the planets condensed out of a spinning cloud of gas and dust |
|
|
Term
|
Definition
| a large cloud of gas and dust such as the one that formed our solar system |
|
|
Term
| Solar Nebula's Four materials |
|
Definition
1) Hydrogen and Helium gas (98%)
2) Hydrogen Compounds
3) Rock
4) Metal |
|
|
Term
|
Definition
| The boundary in the solar nebula beyond which ices could condense; only metals and rocks could condense within the frost line |
|
|
Term
|
Definition
| something contributing to growth or increase |
|
|
Term
|
Definition
| Small planetary objects that form through the action of gravity during the birth of a solar system |
|
|
Term
|
Definition
| a stream of protons moving radially from the sun |
|
|
Term
|
Definition
| Second stage in the formation of terrestrial (inner) planets. Continued accretion of planetesimals in the form of meteors, asteroids, and small planets continually hitting the rocky surface and adding mass and heat to the planet (∼4.0 to ∼3.0 billion years ago) |
|
|
Term
|
Definition
| collision between a forming planet and a very large planetesimal, such as is thought to have formed our moon |
|
|
Term
|
Definition
| the process of measuring the absolute age of geologic material by measuring the concentrations of radioactive isotopes and their decay products |
|
|
Term
|
Definition
| isotope in which the nucleus decays (breaks down) over time, giving off radiation in the form of matter and energy |
|
|
Term
|
Definition
| the spontaneous disintegration of a radioactive substance along with the emission of ionizing radiation |
|
|
Term
|
Definition
| Compounds that contain hydrogen and were common in the solar nebula, such as water, ammonia, and methane |
|
|
Term
|
Definition
| Mercury, Venus, Earth, Moon, Mars. These planets share a common ancestry - birth from a solar nebula about 4.6 billion years ago |
|
|
Term
|
Definition
| Planet's surface features can be traced back to fundamental properties |
|
|
Term
| comparative planetary geology |
|
Definition
| A planet's surface properties can be traced back to its fundamental properties |
|
|
Term
| Terrestrial planet layering |
|
Definition
| Gravity is responsible for this |
|
|
Term
|
Definition
| Process where gravity separates materials by density, when they were molten throughout their interiors |
|
|
Term
|
Definition
| Dense metal thing through molten rock toward the planet's center |
|
|
Term
|
Definition
| Rocky material rest in the middle came to rest above the core composed of silicates - minerals that contain silicon and oxygen |
|
|
Term
|
Definition
| Lowest density rocks, rose to the surface |
|
|
Term
|
Definition
Outer layer of rigid rock, includes crust and upper mantle, the thickness determines longevity of geology activity
- determined by strength of rock |
|
|
Term
|
Definition
Underlying layer of softer that can deform.
- determined by strength of rock |
|
|
Term
|
Definition
| Driven by convection, building of surface features by stretching compression, and other forces acting on the lithosphere |
|
|
Term
|
Definition
| Move over, under, and around each other |
|
|
Term
|
Definition
| Idea that continents drift around planet. Means earth is geologically active. |
|
|
Term
|
Definition
| Created by interior heat through convection conduction |
|
|
Term
| How planetary interiors get hot |
|
Definition
1) heat of accretion: many violent impacts early in solar system history, melted the planets
2) The Melting allowed for differentiation
3) decay of radioactive elements, this is what is keeping the earth hot. |
|
|
Term
|
Definition
| Taking heat from interior, leaking out thermal radiation |
|
|
Term
|
Definition
| Carries energy away and therefore cools and object |
|
|
Term
|
Definition
| The creation of balance sheet impact craters by asteroids or comet striking a planet's surface |
|
|
Term
|
Definition
| Volcanic plains shield volcanoes, the reaction of molten rock or lava from a planet and interior onto its surface |
|
|
Term
|
Definition
| The destruction of a planet's surface by internal |
|
|
Term
|
Definition
| The wearing down of building up of geological features by wind, water, ice, and other phenomena of planetary weather |
|
|
Term
|
Definition
| Stuff being blown out from impact |
|
|
Term
|
Definition
| Runniest lava flow, far and flatten out before solidifying |
|
|
Term
|
Definition
Somewhat thicker lavas tend to solidify before they completely spread out
|
|
|
Term
|
Definition
| The thickest lavas cannot flow very far before solidifying and therefore build up tall and deep |
|
|
Term
|
Definition
| The breakdown or transport of surface rock through the action of ice, liquid, or gas |
|
|
Term
|
Definition
| Erosion piled settlements in two layers on the floors of oceans and seas |
|
|
Term
| Role of distance from the Sun |
|
Definition
Close to the Sun
intermediate to the Sun
far from the sun |
|
|
Term
|
Definition
Slow rotation
Rapid rotation |
|
|
Term
|
Definition
| San sized particles from space, burn up in the atmosphere of Earth, Venus, Mars |
|
|
Term
| 1. Describe the core-mantle-crust structures of the terrestrial worlds. What is differentiation? What do we mean by the lithosphere? How does the lithospheric thickness vary among the five terrestrial worlds? |
|
Definition
a. Core- the highest density material, consisting primarily of metals such as nickel and iron, resides in the central core.
b. Mantle- rocky material of moderate density mostly minerals that contain silicon, oxygen, and other elements- forms the thick mantle that surrounds the core.
c. Crust- the lowest density rock, such as granite and basalt (a common form of volcanic rock), forms the thin crust, essentially representing the world's outer skin.
d. Differentiation- the process by which gravity separates materials according to density, with high-density materials sinking and low-density materials rising.
e. Lithosphere- the relatively rigid outer layer of a planet; generally encompasses the crust and the uppermost portion of the mantle.
f. Smaller worlds have thicker lithospheres, and larger have thinner lithospheres. A thin brittle lithosphere can crack easily. A strong one inhibits the passage of molten rock from below, making volcanic eruptions and the formation of mountain ranges less likely. |
|
|
Term
| 2. Summarize the process by which planetary interiors get hot and cool off. Why do large planets retain internal heat longer than smaller planets? |
|
Definition
a. How interiors get hot
i. Heat of accretion- accretion deposits energy brought in from afar by colliding planetesimals.
ii. Heat from differentiation- the sinking of dense material and rising of less dense material means that mass moves inward, losing gravitational potential energy. This energy is converted to thermal energy by the friction generated as materials separate by density.
iii. Heat form radioactive decay- when radioactive nuclei decay, subatomic particle fly off at high speeds, colliding with neighboring atoms and heating them.
b. How interiors cool off
i. Convection- the energy transport process in which warm material expands and rises while cooler material contracts and falls.
ii. Conduction- (of energy) the process by which thermal energy is transferred by direct contact from warm material to cooler material.
iii. Radiation- (light) is carries energy away and therefore cools an object.
c. Because larger planets have more insulation. |
|
|
Term
| 3. Why does Earth have a global magnetic field? Why don't the other terrestrial worlds have similarly strong magnetic fields? |
|
Definition
a. Because it meets the three basic requirements
i. An interior region og electrically conducting fluid (liquid or gas) such as molten metal
ii. Convection in that layer of fluid
iii. At least moderately rapid rotation
b. Earth is the only terrestrial world that meets all three requirements. |
|
|
Term
| 4. Define each of the four major geological processes, and give examples of features shaped by each process. |
|
Definition
a. Impact cratering- the excavation of bowl-shaped depressions (impact craters) by asteroids or comets striking a planet's surface.
i. Scarred faces of the moon and mercury
b. Volcanism- the eruption of molten rock, or lava, from a planet's interior onto its surface.
i. Lava plains on the moon, Olympus Mons (Mars), Mount Hood (Earth)
c. Tectonics- the disruption of a planets surface by internal stresses.
i. Appalachian Mountains, Guinevere Plains on Venus, Ceraunius Valleys on Mars, New Mexico's Rio Grande Valley
d. Erosion- the wearing down or building up of geological features by wind, water, ice, and other phenomena of planetary weather.
i. Glaciers, the craving of canyons, rivers, shifting of sand dunes |
|
|
Term
| 5. What is outgassing, and why is it so important to our existence? |
|
Definition
| a. Outgassing is the process of releasing gases from a planetary interior, usually through volcanic eruptions. It releases some of the trapped up gas that was used in creating the planet. (like a shaken up can of soda) |
|
|
Term
| 6. Why is the moon so much more heavily cratered than earth? Explain how a crater counts tell us the age of a surface. |
|
Definition
a. The moons surface must have stayed virtually unchanged for billions of years. And our surface we see very few craters, so we must be looking at a younger surface, one on which the scars of ancient impacts have been erased over time by other geological processes such as volcanic eruptions or erosions.
b. Crater counts tells us the age of a surface because we can estimate the age by knowing that with more craters indicating that it is older surface. |
|
|
Term
| 7. Summarize the ways in which a terrestrial world's size, distance from the sun, and rotation rate each affect its relative level of impact cratering, volcanism, tectonics, and erosion. |
|
Definition
a. Volcanism/ tectonic-both require internal heat, which means they depend on planetary size. The larger planets have more internal heat and hence more volcanic and tectonic activity.
b. Erosion- requires planetary size it needs an atmosphere, distance from the sun because of its role in temperature (higher temperature the atmospheric gases escape), distance is important because water erosion is more effective with liquid water and not ice or water vapor, rotation rate is important because it is the primary driver of the winds and other weather
c. Impact cratering- they are random events and therefore the creation of craters us bit "controlled" by fundamental planetary objects. But size is the primary factor: larger worlds have more volcanism and tectonics, processes that tend to cover up or destroy ancient impact craters over time. |
|
|
Term
| 8. Briefly summarize the geological history of the Moon. How did the lunar maria form? |
|
Definition
a. During the heavy bombardment craters covered the moon's entire surface. The largest ones fractured the moons lithosphere beneath the huge craters they created. The lava floods came hundreds of millions of years later. The mantle then melted between 3 and 4 billion years ago. Molten rock then welled up through the cracks in the lithosphere, flooding the largest impact craters with lava. The maria are are generally circular because they are essentially flooded craters. Their dark color comes from the dense, iron-rich rock that rose up from the lunar mantle as molten lava. The flat surfaces of the maria tell us that the lunar lava spread easily and far, which mean it was so runny that in places it flowed like rivers of molten rock.
b. Lunar maria is the regions of the Moon that look smooth from Earth and actually are impact basins; we only see a few craters on top. Lava plains created this. The few craters within the maria formed by impacts that occurred after the maria formed, when the heat from radioactive decay was no longer sufficient to produce lava flows. |
|
|
Term
| 9. Briefly summarize the geological history of Mercury. How are Mercury's great cliffs thought to have formed? |
|
Definition
i. Same as the moon basically. Heavy bombardment, then lava covered up some the of craters, it has more huge impact craters.
ii. They formed when tectonic forces compressed the crust, causing the surface to crumple. |
|
|
Term
| 10. Choose five features on the global map of Mars (Figure 9.25) and explain the nature and likely origin of each. |
|
Definition
a. Olympus mons- large volcano created by long-lived plume of rising mantle material that bulged the surface upward and provided the molten rock for the eruptions that built the giant volcanoes.
b. Central region of Tharsis Bulge- line of volcanoes; created by long-lived plume of rising mantle material that bulged the surface upward and provided the molten rock for the eruptions that built the giant volcanoes.
c. Valles marineris- long deep system of valleys made by plate tectonics
d. Hellas basin- large crater |
|
|
Term
| 11. Why isn't liquid water stable on Mars today, and why do we nonetheless think it flowed on Mars in the distant past? |
|
Definition
| a. Current surface conditions do not allow liquid water to remain stable on Mars. In most places and at most times, Mars us so cold that any liquid would immediately freeze into ice. The air pressure is so low that liquid water would quickly evaporate. Mars must once have had very different surface conditions- conditions such as warmer temperatures and greater air pressure that would have allowed water to flow and rain to fall. |
|
|
Term
| 12. Choose at least three major geological features of Venus and explain how we think each one is formed. |
|
Definition
a. Ishtar Terra- large elevated surface
b. Aphrodite Terra- large elevated surface
c. Lada Terra- large elevated surface |
|
|
Term
| 13. What evidence tells us that Venus was "repaved" about 750 million years ago? What might account for the lack of plate tectonics on venous? |
|
Definition
a. It has few impact craters all over the planet, suggesting that the surface is about the same age everywhere. It suggests the surface age is about 750 million years old. Therefore, we concluded it had to be repaved erasing all other craters that had formed earlier.
b. Either it has weaker mantle convection or that its lithosphere somehow resists fracturing. |
|
|
Term
| 14. Describe the conveyor-like-action of plate tectonics of Earth, and how it explains the differences between seafloor and continental crust. |
|
Definition
a. Earth's geology as a result of the slow motion of plates that essentially "float" over the mantle, gradually moving over, under, and around each other as convection moves earth's interior rock. Earth's lithosphere is broken into more than a dozen plates.
b. Subduction occurs at ocean trenches, where dense seafloor crust pushes under less dense continental crust, thereby returning seafloor crust to the mantle. The subducting seafloor crust may partially melt, with low-density material melting first and erupting from volcanoes as new continental crust. New seafloor crust is created by eruptions at mid ocean ridges, where plates spread apart.
c. Thw entire seafloor is replaced every 200 million years. |
|
|
Term
| 15. Briefly explain how each of the following geological features of Earth is formed: seafloors, continents, islands, mountain ranges, rift valleys, and faults. |
|
Definition
a. Seafloors- plate tectonics
b. Continents- volcanism and stresses associated with plate tectonics and erosin.
c. Islands- plate tectonics
d. Mountain ranges-
e. Rift valleys- continental plates are pulling apart
f. Faults- tectonic plates flip sideways |
|
|
Term
| 16. To what extent do we think the geologies of the terrestrial worlds were destined form their birth? Explain. |
|
Definition
a. By the fundamental properties of size, distance from the sun and rate of rotation.
b. All the planets were heavily cratered during the heavy bombardment. Size affects volcanism and tectonics. |
|
|
Term
| 1. Briefly summarize the atmospheric properties of the five terrestrial worlds. How do they differ in surface temperature, pressure, and composition? |
|
Definition
| -No atmosphereVenus- Very Hot, Thick atmosphere, Extreme greenhouse effectEarth- Perfect atmosphereMoon- No atmosphereMars- Carbon dioxide atmosphere with thin air |
|
|
Term
| 2. What do we mean by atmospheric pressure? Why does pressure decrease with altitude? What is 1 bar of pressure? |
|
Definition
| Atmospheric Pressure: Collisions of molecules in all directions. Farther down, more air pressing down, heavier pressure. 1 bar is 14. 7 pounds per square inch. |
|
|
Term
| 3. Is there any atmosphere at the orbital altitude of the Space Station above Earth? Explain. |
|
Definition
| Yes, it's just extremely thin. Earths atmosphere extends for nearly 100 km. |
|
|
Term
| 4. What is the greenhouse effect? Describe how it warms a planet. |
|
Definition
| Certain air molecules absorb infrared better. These include water vapor (H2O), Carbon Dioxide (CO2), and methane (CH4). Thus, when they absorb infrared, they heat up, and heat up atmosphere. |
|
|
Term
| 5. If there were no greenhouse effect, what factors would determine a planet's surface temperature? How do the "no greenhouse" temperatures of the terrestrial planets compare to their actual temperatures, and why? |
|
Definition
| Planets distance from the sun, and the planets overall reflectivity. No greenhouse means much less cooler. |
|
|
Term
| 9. Why does convection occur in the troposphere, leading to active weather, but not in the stratosphere? |
|
Definition
| Convection causes heating in troposphere because it drops in temperature with altitude, but has a relatively high density of air. The stratosphere has no weather because convection cannot happen because the air gets hotter in this layer as you go up in altitude. Air cannot rise if the air above it is hotter, so the air is stagnant. |
|
|
Term
| 10. What is ozone? How does the absence of ozone on Venus and Mars explain why these planets lack a stratosphere? |
|
Definition
| Ozone (O3) are molecules that are particularly good at absorbing ultraviolet photons. Because earth is the only terrestrial planet with oxygen, other planets cannot have an ozone, and thus cannot have a stratosphere. |
|
|
Term
| 12. What causes seasons? How and why do seasons on Mars differ from seasons on Earth? |
|
Definition
| [This is review] Tilt is different. |
|
|
Term
| 13. Describe Earth's global wind patterns and the role of circulation cells. How does rotation affect these cells? |
|
Definition
| Warm air flows towards poles, cool air flows toward equator. Rotation causes air to turn in opposite direction with the Coriolis effect. |
|
|
Term
| 14. Describe each of the four factors that can lead to long-term climate change. |
|
Definition
Solar Birghtening: The sun has grown gradually brighter with time, increasing the amount of solar energy reaching the planets.
Changes in tilt Axis: Tilt may change over long time.
Changes in reflectivity: Decreases/ increases amount of sunlight absorbed.
Changes in greenhouse gas abundance: More= hotter, less= cooler. |
|
|
Term
| 15. Describe each process by which atmospheres gain or lose gas. What factors control thermal escape? Which loss processes are permanent? Which are temporary? |
|
Definition
Outgassing, Evaporation/Sublimation, surface ejection = Gain
Condensation, Chemical Reactions, Solar Wind Stripping, Thermal escape = Loss |
|
|
Term
| 16. Why do the Moon and Mercury have so little atmospheric gas? How is it possible that they might nonetheless have water ice in polar craters? |
|
Definition
| Small size lets gas escape. Comets may have crashed and embedded ice into the planets. |
|
|
Term
| 17. How do we think that Mars lost atmospheric gas? What basic planetary property (size, distance from the Sun, or rotation rate) would have had to be different for Mars to have retained a thicker atmosphere? |
|
Definition
| Convection rised gas and the weak magnetic field (weakened as the small planet cooled and core convection ceased) allowed for solar wind particles to strip the atmosphere into space. Size. |
|
|
Term
| 18. What do we mean by a runaway greenhouse effect? Explain why this process occurred on Venus but not on Earth. |
|
Definition
| Venus is closer to the sun. Hotter temp = more evaporation = hotter atmosphere = hotter temp = more evaporation, etc... UV rays would tear away hydrogen atoms, leaving Venus as we know it. |
|
|
Term
| Gravitational Equilibrium |
|
Definition
| How the sun maintains its size, structure, and shape. The outward force of the gas pressure is equal to the inward, gravitational force of all atoms. |
|
|
Term
|
Definition
| around 109 times the Earth's Radius |
|
|
Term
|
Definition
| around 300,000 times the Earth's mass |
|
|
Term
| Surface Temperature (sun) |
|
Definition
|
|
Term
|
Definition
|
|
Term
| Basic Composition From inside to the outside: (sun) |
|
Definition
| Core, Radiative Zone, Convective Zone, Photosphere, Chromosphere, Corona, Solar Wind |
|
|
Term
| Characteristics of the Core Place where fusion takes place (sun) |
|
Definition
15,000,000 Kelvin
200 billion times the Earth's atmospheric pressure |
|
|
Term
| Characteristics of the Radiative Zone (sun) |
|
Definition
Hot enough to create plasma (ionized atoms)
Don't do the absorption/emission process
Photons from core collide with individual charged particles |
|
|
Term
| Characteristics of the Convective Zone (sun) |
|
Definition
Transport of energy due to motion of liquid or gas.
Energy from the middle of the sun gets to surface via convection of hydrogen gas. |
|
|
Term
| Characteristics of the Photoshpere (sun) |
|
Definition
Gas dense enough to be visible
Density is much less than the Earth's atmosphere
Surface has a granular (mottled) appearance |
|
|
Term
| Characteristics of the Chromoshpere (sun) |
|
Definition
Lower temperature than the Corona (around 10,000 Kelvin)
gives off ultraviolet photons and visible light
visible during a total eclipse |
|
|
Term
| Characteristics of the Corona (sun) |
|
Definition
Very low density gas
very high temperature (about 1,000,000 Kelvin)
gives off high energy x-ray photons |
|
|
Term
|
Definition
| the process of bringing together two nuclei to to make a larger one. This is the Sun's light making process. |
|
|
Term
|
Definition
| The inverse of fusion. The process of breaking apart a nuclei into two smaller nuclei. |
|
|
Term
|
Definition
Strong magnetic fields in them
Cooler than the surrounding surface
Usually appear in pairs
Follow 11 year cycle |
|
|
Term
|
Definition
| Magnetic field line arc which carries gas and ions off surface into the chromosphere and the corona. |
|
|
Term
|
Definition
| Twisted Magnetic field lines that break apart to realign and release energy, x-rays, and fast moving particles |
|
|
Term
|
Definition
Basically very large Solar Flares.
gives off charged particles and ionized gases |
|
|
