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Updated: Jul 12, 2026

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Utilizing Soil Density Fractionation to Separate Distinct Soil Carbon Pools
Published on: December 16, 2022
Total carbon and nitrogen abundances in lunar samples
Summary
This study quantifies total carbon and nitrogen in lunar fines using combustion-gas chromatography. Results indicate these elements are mixtures of indigenous lunar material, meteoritic, and solar wind components.
Area of Science:
- Geochemistry
- Lunar Science
- Planetary Science
Background:
- Understanding the composition of lunar regolith is crucial for lunar exploration and resource utilization.
- Previous studies have provided varying estimates for carbon and nitrogen content in lunar samples.
Purpose of the Study:
- To accurately determine the total carbon and nitrogen abundances in various lunar fines.
- To investigate the sources of carbon and nitrogen in lunar samples.
Main Methods:
- Combustion-gas chromatographic techniques were employed for precise elemental analysis.
- Samples were sieved into different fractions to analyze size-dependent variations.
Main Results:
- Weighted mean analyses revealed 225 ppm total carbon and 150 ppm total nitrogen in bulk fines.
- Carbon content varied from 64 ppm in medium-grained rock to 230 ppm in fine breccia.
- Nitrogen content ranged from 30 ppm in medium-grained rock to 125 ppm in fine breccia.
- The finest sieved fraction exhibited the highest carbon content.
Conclusions:
- The determined carbon and nitrogen abundances suggest a mixed origin for these elements in lunar fines.
- Both indigenous lunar material and extraterrestrial inputs (meteoritic and solar wind) contribute to the observed abundances.
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