Cross Lake Project (1983-86)


Geologist    P.G. Lenton     Year    83     STATION    5025
EASTING   568376     NORTHING   6042736     ZONE   14     DATUM   NAD83
Date of mapping    06/20/1983

STRUCTURAL DATA

Planar Structures:
Structure type Strike Dip Separation
cataclastic foliation 312 62
fault 281 80

-photos of incredable mylonite and augen mylonite features
-mylonite layered

PETROLOGIC DATA

Rock Number: 1

Rock Type: gneiss
Descriptors:
augened
granodiorite
tonalitic
shears present or common
cataclastic

Field Description:

-heavily sheared - both tonalite and granodiorite present but so intimately associated because of heavy cataclasis that you can't really separate phases.
-There appears to be some warping and distortion of the mylonite by later penetrative shear

PHOTOS


Brecciation of old sheared multi-component gneiss by younger small scale cross-cutting mylonite/ultramylonite seams.


Detail of late crosscutting mylonite.(card resting on late surface)


Late granitic lit occupying dextral fractures.


Large augen formed in old leucotonalite by progressive boudinage and rotation of early granite/pegmatite veins.


Manitoba Geological Survey, 2017