Shmidt Peninsula

Small stocks, sheets, laccoliths and dykes of gabbro, gabbro-diorite, essexite, crinanite and teschenite occur within the western (Zapadny) and eastern (Vostochny) ridges of the peninsula. The stocks do not exceed 100-120 m in diameter; the sills are 100-200 m thick and the dykes 2-3 m wide. Essexite dolerites are wholly crystalline fine- and medium-grained rocks composed of labradorite (30-35%), titanaugite (25-30%), olivine (10-15%), biotite (3-5%), analcime (10%) and anorthoclase (10%) with accessory magnetite, ilmenite, titanomagnetite and apatite. The crinanites are rich in analcime (25%) and olivine (20%) and the teschenites include nepheline and natrolite.