Cross Lake Project (1983-86)

Geologist P.G. Lenton Year 83 STATION 5131
EASTING 577043 NORTHING 6042783 ZONE 14 DATUM NAD83
Date of mapping 07/10/1983

STRUCTURAL DATA

Dikes and Sills:
Rock Number | Type | Width (m) | Strike | Dip
0 | Molson dike | 90.00 | 228 | 71

-PHOTOS 1 and 2- upper contact cross cutting dike
-PHOTOS 3 - margin to margin view of crosscutting dike
-PHOTOS 4 - bifurcated cross cutting dike
-PHOTOS 5 AND 6 - detail of crosscutting relationships

PETROLOGIC DATA

Rock Number: 1

Rock Type: gabbro
Field Description:

-dominantly cumulate layered gabbro
(see sample)
-72 m continuous exposure estimated total width between 85 - 90 m
- PHOTO 7 cross cutting dikes, granodiorite country rock

Rock Number: 2

Rock Type: diabase
Field Description:

291/68 163.0 cm
109/88 48.0 cm
-2 dikes enter the contact of major Molson, cooled into a single 2.2 - 3.1 m dike that cross cuts the gabbro dike
-see photos

PHOTOS

Upper leuco gabbro part of Molson gabbro dike crossed by fine grained to aphanitic diabase dike. Note the distinct chill of the diabase against the gabbro.
The crosscutting nature, lack of deformation, planar form and NW-SE orientation suggests this may be a small Mackenzie dike.

Complex instrusive pattern of diabase into the gabbro. Multiple dikes surround and stope the gabbro before merging at the contact with the country rock.

Detail showing delicate intrusion and marginal chill in the diabase.

Diabase intruding fractures in the Molson gabbro

Foreground of picture is the hangingwall of the Molson dike. The assistant is standing on the augen grandiorite country and is bracketed 3-4 m on each side by probable Mackenzie dikes. The diabase dikes deflect into the contact of the gabbro dike, merge and then cross the gabbro dike.

Manitoba Geological Survey, 2017