High-temperature silicified zone
Chemical Process (Alteration) - Open system under ground (Acidic-Neutral metasomatism)
Correlated: Albite-Epidote-hornfels facies
Index Minerals
Quartz, Chlorite, Illite
Required Geological Setting
Metasomatic rocks (Intermediate acidic)
Occurrence
Metasomatic zone formed by acidic-neutral hydrothermal fluid of 250-350 degree associated with Rhyolitic to Dacitic magma activities. This alteration is called high-temperature silicification. Protoliths are felsic rocks. High-temperature silicified zone may be associated with Kuroko massive sulfide deposits, Cyprus-type massive sulfide deposits, Felsic-Siliclastic type massive sulfide deposits, Moderate-T hydrothermal deposits, Moderately high-T hydrothermal deposits, High-T hydrothermal deposits, and/or Pneumatolytic deposits.
Change of mineral assemblages
- [ Extinct ] Smectite
- [ Appear ] Chlorite, Illite
Mineral Assemblages
- Rutile, Quartz, Pyrite, Illite, Chlorite
Localities
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)