Cross Lake Project (1983-86)


Geologist    P.G. Lenton     Year    83     STATION    5015
EASTING   568224     NORTHING   6044484     ZONE   14     DATUM   NAD83
Date of mapping    06/19/1983

STRUCTURAL DATA

Planar Structures:
Structure type Strike Dip Separation
gneissosity 79 50
fault 45 80 dextral

-several aplitic sills in foliation along with usual compliment of pegmatitic stringers

PETROLOGIC DATA

Rock Number: 1

Rock Type: tonalite
Descriptors:
augened
leucocratic

Field Description:

-older tonalite is 95% of exposure
-good 1 cm potassium feldspar augen up to 3% of exposure
-texturally indicative of cataclasis of lit-par-lit gneiss

Textural Features
Type Mineral Min. Size Max. Size Abundance (%) Unit
augen potassium feldspar 0.0 0.0 3.0

Rock Number: 2

Rock Type: granodiorite
Descriptors:
massive
biotite - amphibole bearing
boudin or boudinaged

Field Description:

-several isolated boudins of younger grey non-porphyritic GRDR
-very little injected lit matierial

Textural Features
Type Mineral Min. Size Max. Size Abundance (%) Unit
mafic mineral 0.0 0.0 17.0 mm

PHOTOS


Grey augen tonalite with old pegmatite cut by dextral offset shear filled with late pegmatite.


Outcrop view showing augen tonalite with 3 generations of pegmatite lit/dikes.


Manitoba Geological Survey, 2017