Next Article in Journal
Three-D Mineralogical Mapping of the Kovdor Phoscorite–Carbonatite Complex, NW Russia: I. Forsterite
Previous Article in Journal
Pinnoite Deposit in DaQaidam Saline Lake, Qaidam Basin, China: Hydroclimatic, Sedimentologic, and Geochemical Constraints
Article Menu
Issue 6 (June) cover image

Export Article

Open AccessArticle
Minerals 2018, 8(6), 259; https://doi.org/10.3390/min8060259

Near-Infrared Spectroscopy of Hydrothermal versus Low-Grade Metamorphic Chlorites

1
Faculty of Geo-Information Science and Earth Observation (ITC), University of Twente, 7514 AE Enschede, The Netherlands
2
Department of Earth Sciences, Utrecht University, 3584 CB Utrecht, The Netherlands
*
Author to whom correspondence should be addressed.
Received: 30 April 2018 / Revised: 14 June 2018 / Accepted: 16 June 2018 / Published: 19 June 2018
View Full-Text   |   Download PDF [1698 KB, uploaded 19 June 2018]   |  

Abstract

Although the composition of chlorite group minerals represents a known proxy for conditions in various geological environments, few comparative studies of chlorites from different geological environments have been carried out. In this study, we compare chlorites from a hydrothermal system with those formed under low-grade metamorphic conditions. Both sets of samples were collected from the Pilbara Craton, Western Australia. Near-infrared (NIR) spectroscopy was used to determine if spectral differences record compositional differences between chlorites from the two geological environments. The spectra showed a significant difference in the Mg-OH absorption wavelength, near 2350 nm, with the hydrothermal group showing longer absorption wavelengths than the metamorphic one. A comparison of the spectral data with geochemical analyses showed a relation between the absorption wavelength and the magnesium-to-iron ratio (magnesium number) of chlorite, as well as the bulk rock composition. Metamorphic rocks have a higher magnesium-to-iron ratio than the hydrothermal ones, predominantly explained by differences in the degree of metasomatism. In the hydrothermal system, mass transfer changes the bulk rock composition while for the metamorphic samples the original bulk chemistry determines the current composition of the rock. View Full-Text
Keywords: chlorite; NIR-spectroscopy; metasomatism; basalts; magnesium number chlorite; NIR-spectroscopy; metasomatism; basalts; magnesium number
Figures

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (CC BY 4.0).
SciFeed

Share & Cite This Article

MDPI and ACS Style

Kamps, O.M.; van Ruitenbeek, F.J.; Mason, P.R.; van der Meer, F.D. Near-Infrared Spectroscopy of Hydrothermal versus Low-Grade Metamorphic Chlorites. Minerals 2018, 8, 259.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Minerals EISSN 2075-163X Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top