Alkaline Rocks and Carbonatites of the World

Setup during HiTech AlkCarb: an online database of alkaline rock and carbonatite occurrences

Mann 1

stripes

Occurrence number: 
031-00-155
Country: 
Canada
Region: 
Labrador
Location: 
Longitude: -62.38, Latitude: 54.23
Carbonatite: 
No

The Mann 1 occurrence lies some 12 km northeast of the North Red Wine complex (Fig. 79) and is associated with a fault breccia zone in variable peralkaline syenite. It consists of a lenticular mass of about 2x0.5 km lying between comenditic rocks of the Letitia Lake Group and fine grained, peralkaline syenite. The alkaline rocks appear to be metasomatized and melted Letitia Lake Group rocks, the whole having a migmatitic appearance. The alkaline rocks are correlated by Curtis and Currie (1981) with their hybrid syenites (unit 11) and comprise heterogeneous and fractured rocks with a more leucocratic portion consisting of albite, arfvedsonite and quartz with subordinate aegirine, schizolite, pectolite and aenigmatite, and a host mesocratic rock of plumose albite, with eudialyte, neptunite and pyrochlore. Near pegmatitic veinlets are traces of barylite, eudidymite, neptunite, niobophyllite, pyrochlore and other beryllium minerals.

Economic: 
Prospected as a uranium then as a beryllium deposit. Average grades of 0.35-0.4% BeO were proved in one zone and continued to a depth of at least 60 m (Evans and Dujardin, 1961).
References: 

CURRIE, K.L. 1976a. The alkaline rocks of Canada. Bulletin, Geological Survey of Canada, 239: 1-228.
CURTIS, L.W. and CURRIE, K.L. 1981. Geology and petrology of the Red Wine alkaline complex, central Labrador. Bulletin, Geological Survey of Canada, 294: 1-61.
EVANS, E.L. and DUJARDIN, R.A. 1961. A unique beryllium deposit in the vicinity of Ten Mile Lake, Seal Lake area, Labrador. Proceedings of the Geological Association of Canada, 13: 45-51.
HILL, J.D. and THOMAS, A. 1983. Correlation of two Helikian peralkaline granite-volcanic centres in central Labrador. Canadian Journal of Earth Sciences, 20: 753-63.
Thomas, A. personal communication, 1983.

Map: 
Fig. 1_79 Location of the Mann 1, Mann 2, North Red Wine and South Red Wine occurrences together with other small areas of peralkaline rocks within the vicinity (after Curtis and Currie, 1981, Fig. 39).
Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith