Kiyokawa Mine
Nippara, Okutama city, Nishi-tama county, Tokyo, Japan
Occurrence
High-T zeolite facies bedded manganese deposit
Chert-hosted bedded manganese deposit in a chert block of the Early Jurassic (180 Ma) Ohirayama unit, a member of the Southern Chichibu accretionary complex. The Ohirayama unit has been subjected to weak Prehnite-Pumpellyite to Zeolite facies metamorphism as a low grade part of the Sambagawa metamorphic belt in the Late Cretaceous (100 Ma). The age of chert is Permian Guadalupian (270 Ma) to Early Jurassic (200 Ma). Ages of sedimentary rocks were determined by radiolarians, and metamorphic age by K-Ar or Ar-Ar radiometric dating of muscovite.
Reported Minerals
- Pyrite
- Hausmannite
- Jacobsite
- Pyrochroite
- Manganosite
- Rhodochrosite
- Wiserite
- Rhodonite
Mineral Assemblages
- Hausmannite - Jacobsite - Pyrochroite - Manganosite - Rhodochrosite
- Hausmannite - Wiserite
- Rhodonite - Rhodochrosite - Quartz
History
- 1964: Started to mine.
- 1979: The mine was closed.
Localities
- Kusama Mine (Mudstone-hosted, Miocene)
- Kiyokawa Mine (Chichibu belt)
- Okutama Mine (Chichibu belt)
- Shiromaru Mine (Braunite, Chichibu belt)
Related Occurrences
- Bedded Mn (Diagenesis)
- Bedded Mn (Low-T zeolite facies)
- Bedded Mn (High-T zeolite facies)
- Bedded Mn (Prehnite-Pumpellyite facies)
- Bedded Mn (Pumpellyite-Actinolite facies)
- Bedded Mn (Greenschist facies)
- Bedded Mn (Epidote-Amphibolite facies)
- Bedded Mn (Amphibolite facies)
- Bedded Mn (Albite-Epidote-hornfels facies)
- Bedded Mn (Hornblende-hornfels facies)
- Bedded Mn (Pyroxene-hornfels facies)