Cross Lake Project (1983-86)


Geologist    P.G. Lenton     Year    84     STATION    5448
EASTING   574531     NORTHING   6059288     ZONE   14     DATUM   NAD83
Date of mapping    06/22/1984

STRUCTURAL DATA

Layering:
Layering type Strike Dip top Direction
bedding 57 80

Planar Structures:
Structure type Strike Dip Separation
schistosity 57 80

Dikes and Sills:
Rock Number Type Width (m) Strike Dip
0 Molson dike 0.10 43 81
0 Molson dike 2.00 43 81

Linear Structures
Type Plunge Azimuth
clast elongation 0 0

PETROLOGIC DATA

Rock Number: 1

Rock Type: conglomerate

Field Description:

-trough conglomerate and cross bedded sandstone unit across whole island
-many mylonite zones in the section; section is so uniform I can't tell if faults cut out or duplicate sections
-troughs seem to average 3 to 5 m wide and migrate cross section at will
-flattening and (minor folding?) to sever to get any reliable top control
-sample of massive sandstone unit 40 cm thick

Rock Number: 2

Rock Type: pegmatite

Field Description:

-series of 30 to 50 cm fairly parallel sided dikes
-abundant euhedral pale green beryl
-garnet-apatite intergrowths
-looks like traces of opaques, probably are but can't tell for sure
-there is no doubt here what controlled emplacement-all dikes lie between mylonite zones
-they also are sheared with MV (secondary) along shear planes-beryls shattered
-sample-has circled crystal-may be beryl but form looks wrong-X-ray

Minerals of Note
Mineral Abundance (%)
beryl
apatite
garnet
tourmaline


Manitoba Geological Survey, 2017