Cross Lake Project (1983-86)


Geologist    P.G. Lenton     Year    84     STATION    5582
EASTING   579769     NORTHING   6060766     ZONE   14     DATUM   NAD83
Date of mapping    07/12/1984

STRUCTURAL DATA

Planar Structures:
Structure type Strike Dip Separation
cataclastic foliation 66 89

PETROLOGIC DATA

Rock Number: 1

Rock Type:

Field Description:

-this is one bitch of an outcrop!
-everything I've seen in the last two days is in this one exposure
-the whole exposure is cataclastic to locally mylonitic
-basically there are 3 rock types
(1) assorted mafic volcanics
(2) assorted gabbros
(3) assorted dacite porphyries

-they appear to be fault slices stacked together like a deck of cards
-basic distribution is gabbro to SE, basalt to NW and dacite down the middle
-the dacite is exposed in several layers from 1 to 10 m thick and appears to be dominantly fragmental quartz porphyry
-the basalt was probably a mixture of pillowed, massive and breccia layers but is just a streaky amphibole now
-the gabbro is much the same as previous stations but most is reduced to mafic augen gneiss (see sample 3)


Manitoba Geological Survey, 2017