Cross Lake Project (1983-86)

Geologist P.G. Lenton Year 84 STATION 5406
EASTING 576038 NORTHING 6060534 ZONE 14 DATUM NAD83
Date of mapping 06/13/1984

STRUCTURAL DATA

Planar Structures:
Structure type | Strike | Dip | Separation
schistosity | 233 | 84 |

-Deformation ratio: 1:8:24, for felsic liths
-flattening ratio in mafics is much higher

PETROLOGIC DATA

Rock Number: 1

Rock Type: sandstone
Descriptors:
pebbly
lithic
Field Description:

-fairly uniform section of quartz rich lithic wacke impart a matrix supported conglomerate
-deformation is extreme
-exomorphic tourmineralization assoc. with pegmatite extends greater than 20 m
-mafic clasts are preferably replaced by tourmaline
-garnet largely disappears in tourmineralized segments
-remnant laminations in troughs are visable but highly deformed and reorientated

Minerals of Note
Mineral | Abundance (%)
garnet
muscovite

Rock Number: 2

Rock Type: pegmatite
Descriptors:
granitic
Field Description:

-highly deformed and sheared to feldspar pegmatite
-tourmaline alteration extensive along contacts
-contacts are assymetrically folded (S fold) to pervasive axial planar schistocity, marked by extensive growth of late muscovite on the margins changing to discrete shears in the blocky core
-apatite is pretty turqoise colour and is fairly rare, most common in marginal zones
-traces of pale orange garnet, probably spessartines associated with columnar tourmaline
-microcline is perthitic, and slightly graphic

Minerals of Note
Mineral | Abundance (%)
tourmaline
muscovite
apatite

Manitoba Geological Survey, 2017