Cross Lake Project (1983-86)


Geologist    P.G. Lenton     Year    83     STATION    5212
EASTING   573357     NORTHING   6049096     ZONE   14     DATUM   NAD83
Date of mapping    08/18/1983

STRUCTURAL DATA

PETROLOGIC DATA

Rock Number: 1

Rock Type: pegmatite

Field Description:

Anderson A-8

-2.5 m thick dike, strike 302/34. There is a combination schistocity lineation marked by elongate spodumene and tourmaline. It trends 064, dip unknown.
-Mineralogy: microcline, albite, spodumene, tourmaline, muscovite, blue-green apatite, beryl, columbite.
-very little apparent zoning other than a 20 cm cleavlandite wall zone and a 15 mm platy albite border zone with minor tourmaline. Orientation of spodumene and tourmaline appears to be tectonic imposed stunting growth of crystals. ie crystallization is syn-tectonic. There is very little segregation of quartz, in general the dike is quartz poor. Clevelandite is concentrated mainly in the inner margin of the wall zone. The core region has scattered 20 to 30 cm blocky microclines in dominantly clevelandite, anheral microcline, muscovite matrix. Apatite appears to be concentrated in the lower portions of the dike. Beryl is distributed in the apical portions and is quite rare. Shearing is present but not as pervasive as in the previous dikes

PHOTOS


Viiew of dike 5212 (Anderson A-8) looking west taken during extreme low water in 1988 showing the substantially larger shape of the pegmatite and its much greater extent along strike.


Manitoba Geological Survey, 2017