1. Nephelinite is an example of a silica-undersaturated igneous rock.2. Nephelinite is exposed on the islands but is extremely rare.3. Benmoreite, nephelinites , pantellerites and kulaite are found here. 4. These include nephelinite , basanite and peralkaline phonolite, trachyte and comendite lavas. 5. Olivine nephelinite has been collected near these basalts. 6. A normative feldspathoid classifies a rock as silica-undersaturated; an example is nephelinite . 7. Nephelinite is yet richer in Na 2 O plus K 2 O compared to SiO 2.8. The origin of the volcanism is unknown, but is probably related to olivine nephelinite occurs. 9. An example is the Hamada nephelinite lava flow in southwest Japan which occurred in the late Miocene age. 10. Nephelinite is also associated with the highly alkalic volcanism of the Ol Doinyo Lengai volcanic field in Tanzania.
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