Kaolinite zone
Chemical Process (Alteration) - Open system under ground (Acidic metasomatism)
Synonym
Alunite zone (Middle temperature), Argillized zone (Kaolinite)
Index Minerals
Halloysite
Required Geological Setting
Occurrence
Metasomatic zone formed by acidic hydrothermal fluid of 100-220 degree associated with Rhyolitic magma activities. This alteration is called kaolinitization (kaolinization) and is a part of alunitization or argillization. Protoliths are felsic rocks. Kaolinite zone may be associated with Low-T hydrothermal deposits.
Distribution of kaolinite zones described in this site. Yellow lines are volcanic fronts.
Change of mineral assemblages
- [ Extinct ] Halloysite, Cristobalite
- [ Appear ] Kaolinite, Quartz, Smectite/Illite, Smectite/Chlorite
Mineral Assemblages
- Alunite, Kaolinite, Quartz, Pyrite, Smectite/Illite, Smectite/Chlorite, (Böhmite, Gypsum, Anhydrite)
Localities
- Mount Meshimori (Kaolinite)
Related Occurrences
- Halloysite zone (Alunite zone, Argillized zone)
- Kaolinite zone (Alunite zone, Argillized zone)
- Minamiite-Alunite zone (Alunite zone)
- Pyrophyllite zone
- Smectite zone (Argillized zone)
- Interstratified mineral zone (Argillized zone)
- Illite-Chlorite zone (Propylite zone)
- Epidote-Actinolite zone
- Stilbite-Mordenite zone (Zeolite zone)
- Heulandite-Analcime zone (Zeolite zone)
- Laumontite-Albite zone (Zeolite z., Propylite z.)
- Wairakite-Albite zone (Zeolite zone)