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Lunar sample 14425: characterization and resemblance to high-magnesium microtektites.
Science (New York, N.Y.)
|February 1, 1985
Summary
Analysis of lunar sample 14425 reveals a unique noritic composition, rich in aluminum and magnesium but low in iron and calcium. This glass bead also contains nickel-iron inclusions with sulfur and phosphorus.
Area of Science:
- Geology
- Planetary Science
- Materials Science
Background:
- Lunar samples provide crucial insights into the Moon's geological history and composition.
- Understanding the elemental makeup of lunar materials aids in comparative planetology.
Purpose of the Study:
- To determine the surface composition of lunar sample 14425, a large glass bead.
- To characterize the elemental composition of spherical inclusions within the sample.
Main Methods:
- Energy-dispersive X-ray analysis was employed to measure the surface composition.
- Detailed elemental analysis was performed on the glass matrix and inclusions.
Main Results:
- Lunar sample 14425 exhibits a noritic composition, notably enriched in aluminum and magnesium.
- The sample shows depletion in iron and significant depletion in calcium compared to other norites.
- Spherical nickel-iron inclusions, comprising ~1% of the volume, are enriched in sulfur and phosphorus at the surface.
Conclusions:
- Lunar sample 14425 possesses a distinct geochemical signature, differing from typical norites.
- Its composition aligns closely with basic microtektites, suggesting potential formation or transport mechanisms.
- The presence and composition of nickel-iron inclusions offer clues about the sample's origin and evolution.
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