Minerals and Origin of the Moon

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Minerals and Origin of the Moon

• Triana Henz

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Formation Theories

• Fission
• Capture
• Co-formation
• Giant Impact

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Data

• High angular momentum
• Low iron core
• Identical abundances of oxygen isotopes

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Giant Impact Exchange
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Giant Impact Uncertainty

• Faster cooling rate
• Rotation of disk might have inhibited radial
  diffusion
• Either enrich or same as the Earth in REE,
  thorium, uranium, zirconium and FeO

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Mineral Make up

• Thick crust has feldspar and pyroxene
• Feldspar is mainly anorthite (CaAl2Si2O8 ) ,
  especially if the melt is pyroxene and olivine
  rich
• Low density means that it most likely doesnt
  have an iron core
• Same density as ordinary rock

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Phenomenon

• Pristine highland rocks are extremely rare
• Probably due to gardening of the surface
• Highland is made from molten lunar material that
  crystallized slowly from deep inside
• Magma ocean froze over
• Radioactive isotopes decayed, warming up interior
• Basalt erupted to low areas

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Composition

• Olivine dense, in interiors and lava
• Pyroxene constituent in interiors where metallic
  iron is present
• Feldspar less dense, crust
• Ilmenite lava, titanium bearing

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Composition

• Eutectic composition can shift with pressure
• Determine depth of lava source

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Composition

• REE fit in where they can
• Feldspars rejects lighter REE
• Feldspars accepts denser REE
• Pyroxene is opposite
• Olivine rejects all
• Europium (Eu) is a characteristic of feldspars

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References

• Taylor, G. J. (2008). "Compositional Balancing
  Before Moon Formation." Planetary Science
  Research Discoveries. http//www.psrd.hawaii.edu/F
  eb08/EarthMoonFormation.html