Next Article in Journal
Implicit 3D Modeling of Ore Body from Geological Boreholes Data Using Hermite Radial Basis Functions
Previous Article in Journal
Importance of Magmatic Water Content and Oxidation State for Porphyry-Style Au Mineralization: An Example from the Giant Beiya Au Deposit, SW China
Previous Article in Special Issue
Infra Red Spectroscopy of the Regulated Asbestos Amphiboles
Article Menu

Export Article

Open AccessArticle
Minerals 2018, 8(10), 442; https://doi.org/10.3390/min8100442

Naturally Occurring Asbestos (NOA) in Granitoid Rocks, A Case Study from Sardinia (Italy)

1
Department of Science, Università Roma Tre, Largo S. Leonardo Murialdo 1, 00146 Rome, Italy
2
Department of Seismology and Tectonophysics, Istituto Nazionale di Geofisica e Vulcanologia, Via di Vigna Murata 605, 00143 Roma, Italy
3
Department of Earth Science, Sapienza-Università di Roma, Piazzale Aldo Moro 5, 00185 Roma, Italy
*
Author to whom correspondence should be addressed.
Received: 12 September 2018 / Revised: 28 September 2018 / Accepted: 4 October 2018 / Published: 10 October 2018
(This article belongs to the Special Issue Occurrence, Crystal-Chemistry and Properties of Fibrous Minerals)
Full-Text   |   PDF [15068 KB, uploaded 10 October 2018]   |  

Abstract

All six minerals defined as “asbestos” by the existing regulation on asbestos hazard, i.e., actinolite, tremolite, anthophyllite, crocidolite and amosite amphiboles, and the serpentine-group mineral chrysotile are typical constituents of mafic and ultramafic magmatic rocks of ophiolitic sequences. However, little is known about the presence and distribution of naturally occurring asbestos (NOA) in plutonic felsic rocks. The Isadalu magmatic complex outcropping in central Sardinia and belonging to the post-variscan Permian volcanic cycle, is described here as an interesting occurrence of fibrous amphiboles in granitoid rocks. Field work and collected mineralogical/petrological data show that NOA fibers from the Isadalu complex belong compositionally to the actinolite-tremolite series. They were generated by metasomatic growth on pristine magmatic hornblende, at ca. 470 °C at 1 kbar, during sodic-calcic hydrothermal alteration. In terms of environmental hazard, the Isadalu complex represents a high-value case study, since the actinolite-bearing felsic rocks outcrop in a strongly anthropized area. Here, towns with local and regional strategic infrastructures (dams, pipes, hydroelectric power plants, water supply, roads) have been developed since the last century, also using the granitoid asbestos-rich stones. The aim of this study is to demonstrate that NOA and relative hazard are not univocally connected to a restricted typology of rocks. This result should be taken into account in any future work, procedure or regulation defining asbestos occurrences in natural environments. View Full-Text
Keywords: actinolite; tremolite; asbestos; granite; late variscan magmatism; Sardinia; amphibole; sodic-calcic hydrothermal alteration actinolite; tremolite; asbestos; granite; late variscan magmatism; Sardinia; amphibole; sodic-calcic hydrothermal alteration
Figures

Graphical abstract

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).

Supplementary material

SciFeed

Share & Cite This Article

MDPI and ACS Style

Lucci, F.; Della Ventura, G.; Conte, A.; Nazzari, M.; Scarlato, P. Naturally Occurring Asbestos (NOA) in Granitoid Rocks, A Case Study from Sardinia (Italy). Minerals 2018, 8, 442.

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