Chapter 7 Flashcards
Whats in the earth’s interior?
1) Core
2) Mantle
3) Crust
Differentiation =
means everything moved because of density
- gravity pulls high density material to center
- lower density material rises to surface
- material separates by density
- needs a molten interior!!!
Lithosphere =
Stonesphere!
- planets outer layer of cool, rigid, rock
- it floats on the warmer, softer rock that lies beneathe
Whats the most important heat source today?
Radioactive Decay
what caused the heating of the interior over time?`
accretion and differentiation when planets were young
What part of earths interior has the lowest density?
Crust made of granite, basalt, etc (in outer part!)
what part of earths interior has the highest density?
Core made of nickel and iron
what part of earths interior has moderate density?
Mantle made of silicon, oxygen, etc
Convection ______ heat as hot material ______ and _______ and _____ material contacts and falls.
- transports
- expands & rises
- cool material
_________ transfers heat from hot material to cool material
Conduction
_________ sends energy into space
Radiation
what cools off faster a big terrestrial planet or a tiny terrestrial planet?
a tiny terrestrial planet
smaller worlds cool off ____ and harden _____
faster, earlier
what does the moon and mercury have in common?
they’re both geologically dead
what does a strong magnetic field need?
reasonable strong rotation and molten metallic core
whats the geological process?
- impact cratering
- volcanism
- tectonics
- erosion
what is volcanism?
eruption of molten rock onto surface
what is impact cratering?
impacts by steroids or comets
what are tectonics?
disruption of a planets surface by internal stress
what is erosion?
surfaces changes made by wind, water or ice
craters are how many times wider than the impactor?
10
when did most cratering happen?
soon after the solar system formed
small craters greatly outnumber what?
large craters
when does volcanism happen?
when molten rock finds it sway through the lithosphere to the surface
what is molten rock called after it reaches the surface?
lava
what is outgassing?
when volcanism also releases gases from earths interior into the atmosphere ( mostly co2)
erosion is a weather driven process that
breaks down or transports rock
what are tectonic forces?
convection of the mantle that creates stress in the crust
what makes mountain ranges?
compression forces
where can the valley form?
where the crust is pulled apart
why is there collisions or separations?
bc of movement in the interior
all xray light is ______ very high in the atmosphere
absorbed
what is Ultraviolet light absorbed by?
ozone
what is greenhouse effect?
when certain molecules let sunlight in but trap escaping infrared photons
whats a greenhouse gas?
any gas that absorbs infrared
a greenhouse gas are molecules with two types of what?
elements (co2, h2o,ch4)
why is the sky blue?
atmosphere scatters blue light from the sun, making it appear to come from different directions
why are sunsets red?
bc less of the red light from the sun is scattered
what do they believe flooded lunar craters creating lunar maria?
volcanic activity 3 billion years ago
the smooth regions in mercury are likely…
ancient lave flows
whats the largest impact crater on mercury?
Caloris Basis (end of Solar system formation)
Region ______ the Caloris Basin is ______ from seismic energy of impact
opposite,
jumbled
what do long cliff on mercury indicate?
that it shrank early in its history
mercurys mantle and core shrank causing
its crust to contract
mars is ____% of earths radius and ____ % mass?
50% radius, 10% mass
MARS IS SMALLER
how far is venus from sun?
1.5 AU
thin atmosphere means
little green house effect (cold)
the elliptical orbit makes
the southern hemispheres seasons more extreme
climate change on mars
- no surface water
- lost most of its atmosphere
- greenhouse effect probably kept the surface warmer before that
no magnetic field in mars because…
the core is cold
Describe the atmosphere of Venus
very thick carbon dioxide atmosphere
-surface pressure 90x that of earth
greenhouse effect on venus
- thick carbon atmosphere produces extremely strong greenhouse effect
- most of earths carbon and water are in the oceans and rocks
What unique features of earthare important to life
- surface liquid water
- atmospheric oxygen
- plate tectonics
- climate stability
what makes surface liquid possible?
earths distance from the sun and moderate greenhouse effects
what makes atmospheric oxygen?
photosynthesis
why are plate tectonics a unique feature important for life?
plate tectonics are an important step in the carbon dioxide cycle
what can motion of the continents be measured with?
GPS (a few centimeters per year)
what is subduction?
a process which seafloor is recycled.
-seafloor descends into the mantle below crust
carbon dioxide cycle
- co2 dissolves in rainwater
- rain erodes mineral that flow into the ocean
- minerals combine with carbon to make rocks on ocean floor
- subduction carries carbonate rocks down into mantle
- rock melts into mantle and outgases co2 back into atmosphere through volcanoes
what makes the planet habitable?
large enough for geological activity to release and retain water and atmosphere
-optimal distance
planetary destiny
it is at right distance from the sun so oceans could form
