Next Article in Journal
Acknowledgement to Reviewers of Minerals in 2017
Next Article in Special Issue
Origin of Reverse Zoned Cr-Spinels from the Paleoproterozoic Yanmenguan Mafic–Ultramafic Complex in the North China Craton
Previous Article in Journal
Sb-Bi Alloys and Ag-Cu-Pb-Sb-Bi Sulphosalts in the Jialong Cu-Sn Deposit in North Guangxi, South China
Article Menu
Issue 1 (January) cover image

Export Article

Open AccessArticle
Minerals 2018, 8(1), 27; https://doi.org/10.3390/min8010027

Following the Amphibolite to Greenschist Metamorphic Path through the Structural Parameters of Spinels from Amsaga (Mauritania)

1
Dipartimento di Matematica e Geoscienze, University of Trieste, Via Weiss 8, I-34128 Trieste, Italy
2
Department of Geosciences, Swedish Museum of Natural History, Box 50007, SE-10405 Stockholm, Sweden
3
Dipartimento di Scienze Chimiche e Geologiche, Università di Cagliari, Via Trentino 51, 09127 Cagliari, Italy
4
Géosciences Environnement Toulouse (GET), Observatoire de Midi-Pyrénées, Université de Toulouse, CNRS, IRD, 14 avenue Edouard Belin, F-31400 Toulouse, France
5
Geological Institute, ETH Zürich, 8092 Zürich, Switzerland
*
Author to whom correspondence should be addressed.
Received: 24 November 2017 / Revised: 9 January 2018 / Accepted: 15 January 2018 / Published: 18 January 2018
(This article belongs to the Special Issue Spinel Group Minerals)
View Full-Text   |   Download PDF [6096 KB, uploaded 18 January 2018]   |  

Abstract

We investigated the crystal and structural behavior of several Cr-bearing spinels from the Archean chromitites of Amsaga (Mauritania). The chemical and structural data testified a retrograde metamorphism from amphibolite to greenschist facies, witnessed by relative changes in the amount of all the major oxides (Cr, Al, Mg, Fe2+, Fe3+), the relative proportion of Fe3+/Fetot as well as the structural parameters, including the cell edge and the oxygen coordinate. The general agreement between electron microprobe and Mössbauer data indicates that the analyzed spinels are stoichiometric. The structural data revealed that the oxygen positional parameter of amphibole-bearing samples is the highest observed among Cr-bearing spinels with similar Cr# and Mg#. Consequently, it is suggested that a structural study of detrital Cr-spinels could be important in discriminating an amphibole-chromitite source from an ophiolite source. View Full-Text
Keywords: Cr-bearing spinel; chemistry; X-ray single crystal diffraction; Mössbauer spectroscopy; Archean; Mauritania Cr-bearing spinel; chemistry; X-ray single crystal diffraction; Mössbauer spectroscopy; Archean; Mauritania
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).

Share & Cite This Article

MDPI and ACS Style

Lenaz, D.; Skogby, H.; Rigonat, N.; Berger, J. Following the Amphibolite to Greenschist Metamorphic Path through the Structural Parameters of Spinels from Amsaga (Mauritania). Minerals 2018, 8, 27.

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