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...
| Autores: | , , , |
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| Formato: | artículo |
| Estado: | Versión enviada para evaluación y publicación |
| Fecha de publicación: | 2014 |
| País: | Argentina |
| Recursos: | Comisión de Investigaciones Científicas de la Provincia de Buenos Aires |
| Repositorio: | CIC Digital (CICBA) |
| Idioma: | español |
| OAI Identifier: | oai:digital.cic.gba.gob.ar:11746/4550 |
| Acesso em linha: | https://digital.cic.gba.gob.ar/handle/11746/4550 |
| Access Level: | acceso abierto |
| Palavra-chave: | Geología iron-bearing smectites halloysite weathering |
| Resumo: | 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 present. |
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