Trace element detection in anhydrous minerals by micro-scale quantitative nuclear magnetic resonance spectroscopy

Area of Science:

• Geochemistry and Planetary Science
• Analytical Chemistry

Background:

• Nominally anhydrous minerals (NAMs) in terrestrial and planetary rocks contain trace amounts of volatiles, but their distribution and impact on rock properties are poorly understood.
• Accurate quantification of these trace volatiles is crucial for comprehending the evolution of rocky planets and planetesimals.

Purpose of the Study:

• To develop and validate a novel micro-scale Nuclear Magnetic Resonance (NMR) spectroscopy approach for trace-element quantification in NAMs.
• To enhance the detection capabilities for volatiles within geological samples.

Main Methods:

• Utilized micro-scale Nuclear Magnetic Resonance (NMR) spectroscopy with enhanced mass-sensitivity in microcoils.
• Employed simultaneous detection of internal reference nuclei to increase quantification sensitivity.
• Validated the method against standard techniques across their detection limits.

Main Results:

• The developed NMR method demonstrated excellent agreement with established analytical methods.
• Achieved a detection limit of approximately 50 ng/g for trace volatile elements.
• Successfully quantified volatiles in a single, micrometer-sized anorthitic mineral grain.

Conclusions:

• Micro-scale NMR spectroscopy offers a powerful, highly sensitive tool for trace volatile quantification in NAMs.
• This advancement significantly improves the detection capabilities for volatiles in geologically relevant mineral systems.
• The findings contribute to a better understanding of volatile incorporation and its role in planetary evolution.