Epidote-Actinolite zone
Chemical Process (Alteration) - Open system under ground (Neutral metasomatism)
Correlated: Pumpellyite-Actinolite facies, Albite-Epidote-hornfels facies
Synonym
K-feldspar zone
Index Minerals
Actinolite
Required Geological Setting
Occurrence
Metasomatic zone formed by neutral hydrothermal fluid of 300-350 degree associated with Andesitic magma activities. This alteration is called Epidotization. Epidote-Actinolite zone may be associated with Moderately high-T hydrothermal deposits, High-T hydrothermal deposits, Pneumatolytic deposits, or Porphyry copper deposits.
Distribution of Epidote-Actinolite zones described in this site. Yellow lines are volcanic fronts.
Change of mineral assemblages
- [ Appear ] Actinolite, Biotite
Mineral Assemblages
- [ Felsic Rocks ] Illite, Adularia, Quartz, Pyrite, Biotite, Epidote, Albite
- [ Mafic Rocks ] Chlorite, Actinolite, Biotite, Epidote, Prehnite, Garnet, Clinopyroxene, Albite, (Pumpellyite)
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)