Cross Lake Project (1983-86)
Geologist P.G. Lenton
Year 83
STATION 5089
EASTING 568961
NORTHING 6044035
ZONE 14
DATUM NAD83
Date of mapping 07/04/1983
STRUCTURAL DATA
Structure type | Strike | Dip | Separation |
---|---|---|---|
schistosity | 275 | 84 |
-it appears the 2 granodiorite types which are distinctly different on this outcrop may have been responsable for confusion in that highly tectonized outcrops have not allowed differentiation.
-suggest a cross check of previous samples for colour index and intensity of fabric
PETROLOGIC DATA
Rock Number: 1
-relativly undeformed zone with little intrusion of pegmatitic matierial
-age relation to younger intrusives fairly obvious in that rock types 2 and 3 both truncate pegmatite/tonalite layering of S1 age.
Type | Mineral | Min. Size | Max. Size | Abundance (%) | Unit |
---|---|---|---|---|---|
groundmass grainsize | 0.0 | 1.0 | mm | ||
mafic mineral | 0.0 | 0.0 | 4.0 | % |
Rock Number: 2
-age relations indicate intermediate age between types 1 and 3
-exhibits distinct intrusive relations into tonalite, but has its own distinct S2/S3 fabric, not found in rock type 3.
-the amount of injected matierial (mainly 1 to 3 cm granitic aplite and peg.) is much greater than rock type 3
Type | Mineral | Min. Size | Max. Size | Abundance (%) | Unit |
---|---|---|---|---|---|
mafic mineral | 0.0 | 0.0 | 8.0 | % |
Rock Number: 3
-relativly featureless massive grey sandy textured rock
-appears to be youngest of granitic intrusion.
-it is highly deformed and intruded by late pegmatites but largely lacks the early granitic lit and strong S2 fabric
Type | Mineral | Min. Size | Max. Size | Abundance (%) | Unit |
---|---|---|---|---|---|
mafic mineral | biotite | 0.0 | 0.0 | 15.0 | % |
groundmass grainsize | biotite | 0.0 | 0.4 | mm |
Rock Number: 4
-plagioclase rich schlieric pegmatite, biotite strung out in S3 foliation
-feldspars partially granulated with some augen developement
Mineral | Abundance (%) |
---|
biotite |
garnet |
magnetite |
Manitoba Geological Survey, 2017