Skip to Main Content
Skip Nav Destination
GEOREF RECORD

Supergene vermiculitization of a magnesian chlorite; iron and magnesium removal processes

Dominique Proust, J. P. Eymery and Daniel Beaufort
Supergene vermiculitization of a magnesian chlorite; iron and magnesium removal processes
Clays and Clay Minerals (October 1986) 34 (5): 572-580

Abstract

An X-ray powder diffraction study of a vermiculitized chlorite in an amphibole schist near Limoges, France, shows the following weathering sequence: chlorite --> ordered interstratified chlorite/vermiculite --> vermiculite. Moessbauer spectroscopy indicates that vermiculitization proceeded by the release of ferrous iron from the 2:1 mica layer of the chlorite. The ferric iron content of the vermiculite product is almost the same as that of the initial chlorite. Infrared spectroscopy and chemical microprobe analyses show that Mg was preferentially extracted from the hydroxide sheet of the chlorite, whereas the Si and Al contents progressively increased to the point of the formation of a pure dioctahedral aluminous vermiculite. The Si, Al, and Mg removal processes support currently accepted vermiculitization mechanisms, but the behavior of Fe is slightly different. In this weathering sequence, vermiculitization does not appear to have taken place by the oxidation of Fe (super 2+) , but rather, by the simultaneous leaching of Fe (super 2+) and Mg.


ISSN: 0009-8604
Coden: CLCMAB
Serial Title: Clays and Clay Minerals
Serial Volume: 34
Serial Issue: 5
Title: Supergene vermiculitization of a magnesian chlorite; iron and magnesium removal processes
Affiliation: Univ. Poitiers, Lab. Petrol. Surface, Poiters, France
Pages: 572-580
Published: 198610
Text Language: English
Summary Language: French
Publisher: Clay Minerals Society, Clarkson, NY, United States
References: 38
Accession Number: 1987-014048
Categories: Sedimentary petrologyMineralogy of silicates
Document Type: Serial
Bibliographic Level: Analytic
Illustration Description: illus. incl. 3 tables
N42°30'00" - N51°00'00", W05°00'00" - E08°30'00"
Country of Publication: United States
Secondary Affiliation: GeoRef, Copyright 2017, American Geosciences Institute. Abstract, Copyright, Mineralogical Society of Great Britain and Ireland
Update Code: 1987
Close Modal

or Create an Account

Close Modal
Close Modal