Cross Lake Project (1983-86)

Geologist P.G. Lenton Year 86 STATION 6571
EASTING 572184 NORTHING 6043385 ZONE 14 DATUM NAD83
Date of mapping 08/09/1986

STRUCTURAL DATA

-several boulders of sheared Molson have been noted in this channel, although no exposure of Molsons have been found so far
PHOTOS
1 GRDR-PORT intruding AUGN-TNLT
2 detail to show GRDR-PORT truncating old fabric in TNLT
3 and 4 GRDR-PORT dike in old TNLT truncated by camp GRDR

PETROLOGIC DATA

Rock Number: 1

Rock Type: multi-component schlieric gneiss
Field Description:

-Excellent exposure showing age relation between 3 different units of CWB
-The 2 dominent rocks of this outcrop are the old AUGN-TNLT and the young grey PORT-GRDR
-the relationship is obvious that the GRDR intrudes the TNLT
-the GRDR also cuts an old fabric in the TNLT indicating a pre-existing deformation
-associated with this old fabric are abundant LEUC.?? that are not present in the GRDR
-the third rock type is camp GRDR
-although this unit is schlieric and deformed and has the general appearance of an old rock it truncates layers of grey GRDR-PORT
-this finally fixes a relative age for camp GRDR as the distinctive youngest core intrusion in CWB
-The fabrics indicate that there must have been 3 deformational events involved in CWB
-a pre GRDR event, a post GRDR event and a post camp GRDR event
-this can be extrapolated to a 4th event which is indicated by folding of schlieren in camp GRDR, suggestng 2 deformations for camp GRDR. THe last intrusive event on this outcrop is a post camp pink PEGMT with Gr.
PHOTO 5 Fabric in PORT truncated by camp GRDR
PHOTO 6,7,8 Diagramatic explanation of GRDR-PORT, camp GRDR, TNLT
SAMPLES
A: Old TNLT
B: PORT-GRDR
C: CAMP-GRDR

Manitoba Geological Survey, 2017