Cross Lake Project (1983-86)

Geologist P.G. Lenton Year 83 STATION 5086
EASTING 568042 NORTHING 6044110 ZONE 14 DATUM NAD83
Date of mapping 07/04/1983

STRUCTURAL DATA

Planar Structures:
Structure type | Strike | Dip | Separation
gneissosity | 81 | 65 |

PETROLOGIC DATA

Rock Number: 1

Rock Type: granodiorite
Descriptors:
porphyritic
biotite-plagioclase bearing
Field Description:

- Outcrop is 70% younger granodiorite, intruded by numerous intrafolial quartz poor potassic pegmatites.
-moderate injection of highly sheared aplitic matierial.
-in general the extent of lit injection is much greater than typical for the granodiorite

Textural Features
Type | Mineral | Min. Size | Max. Size | Abundance (%) | Unit
groundmass grainsize |  | 0.0 | 3.0 |  | mm
mafic mineral | biotite | 0.0 | 0.0 | 12.0 | %

Rock Number: 2

Rock Type: tonalite
Descriptors:
schlieric or schlieren present
leucocratic
Field Description:

-extremly deformed highly compressive tonalite, biotite schlieren common
-boudinage and augen structures of pegmatitic lit dominate the foliation plane
-folding both ptygmatic and z-assymetric

Rock Number: 3

Rock Type: amphibolite
Descriptors:
layered
biotite - hornblende bearing
Field Description:

-origin uncertain, extensivley intruded by pegmatite
- vague suggestions of layering, may have a sedimentary component.
-probably part of the greenstone environment but far too deformed and recrystallized to be certain.
-forms low flat rubbly outcrops parallel to shoreline

Textural Features
Type | Mineral | Min. Size | Max. Size | Abundance (%) | Unit
mafic mineral |  | 0.0 | 0.0 | 40.0 | %

Manitoba Geological Survey, 2017