The Mass Spectrometry society of Japan - The 71st Annual Conference on Mass Spectrometry, Japan
Japanese

Abstract

Table of contents

Timetable

Plenary Lecture

Symposium Sessions (Day1, Day2, Day3)

Basic Sessions (Day1, Day2, Day3)

Young Researchers' Sessions (Day1, Day2, Day3)

Poster Presentations (Day1, Day2, Day3)

Special Evening Sessions

Corporate Program

Basic Sessions

Day 1, May 15（Mon.）　10:18-10:36　Room B (Room 1202)

1B-O-1018　　PDF

Determination of halogens in geological reference materials using neutron irradiation noble gas mass spectrometry

(1Univ. Tokyo, 2TIRI, 3Univ. Tokyo)
oHirochika Sumino1, Masahiro Kobayashi2, Keisuke Nagao3

Halogens are among the most powerful tracers of volatile cycling in the Earth and planetary sciences. However, few analytical techniques can determine trace amounts of halogens, particularly Br and I in mantle-derived samples. The neutron irradiation noble gas mass spectrometry (NI-NGMS) is capable of measuring very low concentrations of halogens (<1 ppb) in very small samples (<1 mg). We report halogen concentrations determined for geological reference materials and their original blocks using NI-NGMS.
The halogen concentrations are systematically lower than the reference values for halogen-poor samples, probably resulting from contamination on the sample surface while preparing these reference materials. This is because the contaminated component was removed during sample preparation and/or preheating in a vacuum after sample loading into the analysis system.
We also propose an F-determination method using NI-NGMS based on Ne systematics. The F concentrations are consistent with their reference values within the uncertainty or slightly lower than the reference F concentrations. Some Ne might diffuse from the fine-powdered samples. Alternatively, surface contamination observed in Cl, Br, and I may explain the lower concentrations than the reference values.