Transcript GY111 Physical Geology

Solar System
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Nebular Hypothesis: Solar
System was produced by the
gravitational collapse of a gas
cloud – the remnant of a
supernova explosion.
Concentration of heavy elements
in inner planets.
Most of the mass of the Solar
System is composed of H and He
atoms.
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Inner (Terrestrial) Planets: Mercury, Venus, Earth, Mars.
Outer (Jovian) Planets: Jupiter, Saturn, Uranus, Neptune.
Pluto: former moon of Neptune.
Asteroid belts: shattered remains of a proto-planet.
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Mars-sized (33% mass of Earth) impactor
collided during the Hadean.
Isotopic signatures on Earth and Moon are very
similar.
Earth’s gravity would not have been able to
capture a mass as large (25% of Earth) as our
moon.
The melting event triggered by the impact
allowed Earth to differentiate into Crust,
Mantle, and Core.
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Fe-rich core.
Silicate
mantle and
crust.
Differentiatio
n makes
possible plate
tectonics and
the magnetic
field of the
Earth.
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Volcanic outgassing
formed Earth’s early
atmosphere and
hydrosphere (H, N,
CO2, H2O).
Comet impacts also
added gases and
water.
Note that the early
atmosphere lacked
oxygen (O2).
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Haden Eon marked by
bombardment of
asteroids and comets.
Evolution of life was
impossible until heavy
bombardment ceased.
The cratered surface of
the moon best records
the Late Heavy
Bombardment Period.
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Mars has more
extreme
topographic relief
because of the lack
of water erosion.
Olympus Mons:
largest known
volcano in the solar
system (elev.=22
km; 14 miles).
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Mars rovers
have
provided a
wealth of
data about
the planet.
Mars
resembles
Earth more
than any
other planet.
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Stream-cut channels dissect the
topography.
Stratified and cross-bedded sediments.
Evaporite deposits.
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Precipitation of Hematite
from evaporating lake.
Laterally continuous
stratified beds.
Evaporite deposits of
Halite and Gypsum.
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Know difference between inner and outer
planets.
Be familiar with the Impactor hypothesis for
the origin of the moon.
Know the lines of evidence that point to the
past presence of liquid water on Mars.
Know why Olympus Mons is the largest
volcano in the solar system .
Know about the origin and early composition
of Earth’s atmosphere.