Hanazono Valley
Saimaru, Sekimoto village, Kita-Ibaraki city, Ibaraki pref., Japan
Occurrence
Pegmatite associated with granite of the Late Cretaceous (100 Ma) Tabito Pluton intruded in gneiss of the Takanuki metamorphic rocks, a member of the metamorphosed Early Jurassic (180 Ma) accretionary complex. The Takanuki metamorphic rocks have been subjected to Amphibolite to Granulite facies metamorphism by the medium-P Takanuki metamorphism in the Early Cretaceous (110 Ma). The granite of Tabito Pluton is S-type (Ilmenite-series), and its origin is considered as migmatite formed by partial melting of the Takanuki metamorphic rocks. Ages of sedimentary rocks were determined by radiolarians, the Abukuma metamorphism by U-Pb SHRIMP dating of zircon, and the Tabito pluton by K-Ar radiometric dating of hornblende and biotite.
Outcrop of granitic pegmatite of the Tabito Pluton. Gray grains with a vitreous luster are quartz, and pale brown parts are feldspar. Black spots are cross section of prismatic schorl. This pegmatite is approximately 1.0 m in width and traverses schistosity of the host biotite gneiss of the Takenuki Metamorphic Rocks.
Reported Minerals
- Schorl
- Almandine
- Biotite
Mineral Assemblages
- Quartz - Feldspar - Biotite - Schorl
- Quartz - Feldspar - Biotite - Almandine
Localities
- Mount Hanazono (Andalusite)
- Hanazono Valley (Andalusite)
Related Occurrences
- Pegmatite (Abyssal)
- Pegmatite (Muscovite)
- Pegmatite (Muscovite-Rare element)
- Pegmatite (Rare element, Allanite)
- Pegmatite (Rare element, Euxenite)
- Pegmatite (Rare element, Gadolinite)
- Pegmatite (Rare element, Titanium)
- Pegmatite (Rare element, Beryl)
- Pegmatite (Rare element, Phosphate)
- Pegmatite (Rare element, Spodumene)
- Pegmatite (Rare element, Petalite)
- Pegmatite (Rare element, Lepidolite)
- Pegmatite (Rare element, Elbaite)
- Pegmatite (Rare element, Amblygonite)
- Pegmatite (Rare element, Albite-Spodumene)
- Pegmatite (Rare element, Albite)
- Pegmatite (Miarolitic, REE)
- Pegmatite (Miarolitic, Li)
- Pegmatite (Gabbro)