Accession Number:

ADA533860

Title:

Laser-Induced Breakdown Spectroscopy Analysis of Minerals: Carbonates and Silicates

Descriptive Note:

Conference paper

Corporate Author:

ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD WEAPONS AND MATERIALS RESEARCH DIRECTORATE

Report Date:

2007-11-01

Pagination or Media Count:

10.0

Abstract:

Laser-induced breakdown spectroscopy LIBS provides an alternative chemical analytical technique that obviates the issues of sample preparation and sample destruction common to most laboratory-based analytical methods. This contribution explores the capability of LIBS analysis to identify carbonate and silicate minerals rapidly and accurately. Fifty-two mineral samples 18 carbonates, 9 pyroxenes and pyroxenoids, 6 amphiboles, 8 phyllosilicates, and 11 feldspars were analyzed by LIBS. Two composite broadband spectra averages of 10 shots each were calculated for each sample to produce two databases each containing the composite LIBS spectra for the same 52 mineral samples. By using correlation coefficients resulting from the regression of the intensities of pairs of LIBS spectra, all 52 minerals were correctly identified in the database. If the LIBS spectra of each sample were compared to a database containing the other 51 minerals, 65 were identified as a mineral of similar composition from the same mineral family. The remaining minerals were misidentified for two reasons 1 the mineral had high concentrations of an element not present in the database and 2 the mineral was identified as a mineral with similar elemental composition from a different family. For instance, the Ca-Mg carbonate dolomite was misidentified as the Ca-Mg silicate diopside. This pilot study suggests that LIBS has promise in mineral identification and in situ analysis of minerals that record geological processes.

Subject Categories:

  • Physical Chemistry
  • Geology, Geochemistry and Mineralogy
  • Atomic and Molecular Physics and Spectroscopy

Distribution Statement:

APPROVED FOR PUBLIC RELEASE