Prehnite-Pumpellyite facies
Chemical Process (Solid-phase growth) - Burial Metamorphism (Low-T, Low-P)
Correlated: Illite-Chlorite zone, Laumontite-Albite zone, Wairakite-Albite zone
Index Minerals
Prehnite, Laumontite, Wairakite
Required Geological Setting
Accretionary complexes + Middle-P metamorphic rocks
Accretionary complexes + Low-P metamorphic rocks
Occurrence
Metamorphic rocks formed by burial or regional metamorphism in the following condition: 200-350 degree and 0.2-0.4 GPa (5-15 km depth). A metamorphic facies formed in oceanic crusts at subseafloor near mid-ocean ridges. Prehnite-Pumpellyite facies metamorphic rocks are in accretionary complexes near the boundaries of Barrovian-type middle-P metamorphic rocks and Ryoke-type low-P metamorphic rocks.
Distribution of metamorphic rocks subjected to Prehnite-Pumpellyite facies metamorphism described in this site. Protolith of blue dots is bedded Mn deposit, and protoliths of green dots are igneous rocks and sedimentary rocks. Yellow zones are distribution of accretionary complexes.
Change of mineral assemblages
- [ Extinct ] Heulandite, Analcime, Celadonite, Illite/Smectite
- [ Appear ] Prehnite, Pumpellyite, Albite, Laumontite, Wairakite, Epidote, Illite/Chlorite, Antigorite, Talc
Mineral Assemblages
- [ Felsic Rocks ] Quartz, Illite/Chlorite, Albite, Pumpellyite, Epidote, (Stilpnomelane)
- [ Mafic Rocks ] Illite/Chlorite, Prehnite, Albite, Pumpellyite, Epidote, Laumontite, Wairakite, (Calcite, Datolite, Yugawaralite)
- [ Ultramafic Rocks ] Clinochlore, Serpentine (Chrysotile, Lizardite), Talc
- [ Mudstone ] Illite/Chlorite, Albite, Quartz, Graphite
- [ Laterite ]
- [ Bedded Mn ] Pumpellyite-(Mn), Braunite/Hausmannite, Caryopilite, Rhodochrosite, Quartz, (Piemontite)
- [ Carbonate Rocks ] Calcite/Dolomite, Quartz, Talc
Localities
- Onna-Saka (Basalt)
- Hirayama (Basalt)
- Kouragahana (Pillow lava)
- Nakayashiki (Hyaloclastite)
- Iwakake (Hyaloclastite)
- Yadoriki (Tuff)
- Heguri (Sandstone, Gabbro)
- Mount Chiba (Datolite)
- Kami-Ochiai (Axinite-Datolite)
- Nyushima (Axinite-Datolite)
- Nanasawa (Celadonite)
- Oisawa (Celadonite)
- Mount Gozen (Celadonite)
Related Occurrences
- Albite-Epidote-hornfels facies
- Hornblende-hornfels facies
- Pyroxene-hornfels facies
- Sanidinite-hornfels facies