Article contents
The Coalgate Bentonite. A ferriferous-beidellite deposit from Canterbury, New Zealand
Published online by Cambridge University Press: 09 July 2018
Abstract
The Coalgate Bentonite deposit has been formed by the alteration of cryptocrystalline basaltic ash erupted in Upper Miocene to Pliocene times and deposited in a freshwater lake on a land surface of earlier tholeiitic flows. Physical and chemical analysis shows the bentonite to consist essentially of non-swelling (Ca2+ and Mg2+) ferriferous-beidellite with minor ferriferous montmorillonite. The process of montmorillonitization probably involved a crystal chemical structural reorganization without solution or precipitation and occurred in a mildly alkaline environment in which initial reducing conditions become oxidizing.
- Type
- Research Article
- Information
- Copyright
- Copyright © The Mineralogical Society of Great Britain and Ireland 1974
References
- 8
- Cited by