Nemakit And Satellite Plugs

The Nemakit complex is situated on the right bank of the Medvezhya River, a tributory of the Kotui River, 60 km east of the Odikhincha intrusion and is intruded into lower Cambrian limestones, which are metamorphosed near the contact. According to the data of Moore, Ivanov and Safronov the principal rocks are ijolite and melilite rocks, including okaite and turjaite, with a rather limited development of olivinite and a little alkaline syenite. Carbonatites also occur as narrow veins. A number of smaller plugs occur to the northeast and southwest of Nemakit. The one lying to the northeast (Fig. 116) is circular and has an area of 0.4 km 2. It comprises a core of melilitolite with peripheral nepheline syenite. A second plug (Fig. 117) contains the same rock types.