Coexistence of halloysite and iron-bearing clays in an altered ignimbrite, Patagonia, Argentina

The Mamil Choique halloysite deposits of Patagonia, Argentina, contain randomly distributed green clay inclusions and patches within the halloysite mass. Halloysite has been formed from the thorough alteration of rhyolitic to dacitic ash fall tuffs and ignimbrites of the Huitrera Formation, Eocene a...

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Detalles Bibliográficos
Autores: Cravero, Maria Fernanda, Marfil, Silvina Andrea, Ramos, Cinthia Paula, Maiza, Pedro Jose
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2014
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/18393
Acceso en línea:http://hdl.handle.net/11336/18393
Access Level:acceso abierto
Palabra clave:Iron-Bearing Smectites
Halloysite
Weathering
Patagonia
Argentina
https://purl.org/becyt/ford/1.5
https://purl.org/becyt/ford/1
Descripción
Sumario:The Mamil Choique halloysite deposits of Patagonia, Argentina, contain randomly distributed green clay inclusions and patches within the halloysite mass. Halloysite has been formed from the thorough alteration of rhyolitic to dacitic ash fall tuffs and ignimbrites of the Huitrera Formation, Eocene age, under ambient conditions. The smectites present in the clay inclusions have been determined as ferruginous beidellites with variables amounts of Fe3+ in octahedral sites. The weathering activity that caused the formation of halloysite was also responsible for the genesis of the iron-bearing clay minerals, the formation of which was controlled mainly by permeability. Textural variations within the rock indicate favourable local geochemical environments for the formation of the green clay minerals.