Cathodoluminescence study of Calcite in Martian meteorite

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Cathodoluminescence study of
Calcite in Martian meteorite
NASA
T. Nakazato, M. Kayama, H. Nishido, K. Ninagawa,
A. Gucsik, and Sz. Bérczi
Research Institute of Natural Science, Okayama
University of Science Department of Applied
Physics, Okayama University of Science Max Planck
Institute for Chemistry, Department of
Geochemistry Eötvös University, Institute of
Physics, Dept. G. Physics, Cosmic Materials Space
NASA
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Introduction
NASA
CL and Raman spectroscopy were carried out on
Dhofar 019 for origin of calcite.
NASA
NASA
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SNC Martian meteorites
Shergottite

• Olivine bearing Basaltic Shergottite
• Augite , Pigeonite , Maskelynite
• Lherzolitic Shergottite
• Olivine , Pyroxene

Shergottite
Shergottite 1865 India
Shergotty Nakhlite 1911 Egypt
Nakhla Chassignite 1815 France Chassgny
Nakhlite
Chassignite
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Sample (Dhofar 019)

• Classification Olivine bearing Basaltic
  Shergottite
• Constituent minerals Pyroxene, Olivine,
  Maskelynite, merrillite and calcite
• Shock pressure 30 GPa or more
• Formation age 500Ma
• Exposure age 15 million years
• Finding Oman desert
• Weight 1,056 g
• No fusion crust

Photograph of Dhofar 019
Dhofar region
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Color CL images of Dhofar 019
S
L
5mm
Color CL image of Dhofar 019 measured
area
Vein
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CL spectra of calcite ( S and L )
S
L
BSE image of calcite (S , L)
measurement condition 15kv, 1.0nA
CL spectra of calcite (S and L)
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CL spectrum of calcite ( Vein )
Vein
BSE image of calcite (Vein)
measurement condition 15kv, 1.0nA
CL spectrum of calcite (Vein)
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CL spectra of calcite
S
L
BSE image of calcite (S and L)
Vein
CL spectra of calcite in Dhofar019 and
terrestrial calcite
BSE image of calcite (Vein)
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Raman spectra of calcite
measurement condition light source Ar-laser,
514.5nm power 400 mW
Raman spectra of calcite in Dhofar019 and
terrestrial calcite
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Raman peak shift of calcite
Wave numbers of Raman peaks
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Raman peak shift of calcite
Wave numbers of Raman peaks
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Conclusion
CL spectra

• Calcite in Dhofar 019 shows different spectra
  from terrestrial one.

Raman spectra

• Calcite in Dhofar 019 show weaker Raman peak
  than terrestrial one.

Calcite in Dhofar019 Martian origin
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Thank you, very much.