Quick
Search: 		  
advanced search
 GSW Home   GeoRef Home   My GSW Alerts   Contact GSW   About GSW   Journals List   Help 
Clays and Clay Minerals Signup for GSW Email News
JOURNAL HOME HELP CONTACT PUBLISHER SUBSCRIBE ARCHIVE SEARCH TABLE OF CONTENTS
Clays and Clay Minerals; June 2001; v. 49; no. 3; p. 216-226
© 2001 Clay Minerals Society
This Article
Right arrow Figures Only
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in ISI Web of Science
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Dani, N.
Right arrow Articles by Meunier, A.
Right arrow Search for Related Content
GeoRef
Right arrow GeoRef Citation

NORDSTRANDITE IN BAUXITE DERIVED FROM PHONOLITE, LAGES, SANTA CATARINA, BRAZIL

Norberto Dani1, Milton Luiz Laquintinie Formoso1, Alain Decarreau2 and Alain Meunier2

1 Universidade Federal do Rio Grande do Sul, Instituto de Geociências, Avenida Bento Gonçalves 9500, CEP 91501-970, Caixa Postal 15001, Porto Alegre, Brazil
2 Hydrasa UMR 6532 CNRS, University of Poitiers, 40 Avenue du Recteur Pineau, 86022 Poitiers Cedex, France

E-mail of corresponding author: dani{at}if.ufrgs.br

Nordstrandite from Lages represents the first occurrence of this mineral in an oxisoil that does not involve the influence of a calcareous substrate. This is also the first reported occurrence in Brazil. Nordstrandite occurs near the city of Lages only in the weathered bedrock facies, mostly where the circulation of meteoric water is restricted. There is also a close association between nordstrandite and the weathering of modified pseudoleucite structures. The interaction of meteoric water and feldspathic alkaline country rock with uncommon texture and mineralogy (rich in nepheline, sodalite, nosean, analcime and natrolite) promotes the development of solutions enriched in alkaline ions with basic pH, necessary to form nordstrandite. A detailed study by X-ray diffraction (XRD) and infrared (IR) spectroscopy in natural or chemically leached samples was performed to identify the Al(OH)3 polymorphs of gibbsite and nordstrandite.

Key Words: Bauxite • Boehmite • Gibbsite • Nordstrandite • Paraná Basin • Phonolite • Weathering






JOURNAL HOME HELP CONTACT PUBLISHER SUBSCRIBE ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 2009 by Clay Minerals Society