stripes
Occurrence number:
174-00-001
Country:
United States
Region:
Alaska
Location:
Longitude: -160.37, Latitude: 66.33
Carbonatite:
No
The most westerly of the Kobuk-Selawik Lowland alkaline intrusions, the Selawik Lake complex covers 18 km2. In the southeast the complex is in contact with syenites, but elsewhere it is surrounded by Recent sediments. The northern half is composed of leucocratic juvite and borolanite which forms a hill of 8 km2. Kalsilite has been identified in these rocks and melanite is abundant, locally forming up to 15% modally. The southern half is poorly exposed and includes perthosite and malignite.
References:
MILLER, T.P. 1972. Potassium-rich alkaline intrusive rocks of western Alaska. Bulletin of the Geological Society of America, 83: 2111-28
Map:
Fig. 1_121 General distribution of Kobuk-Selawik Lowland alkaline rocks (after Miller, 1972, Fig. 3).
Location: