Cross Lake Project (1983-86)

Geologist P.G. Lenton Year 84 STATION 5665
EASTING 568481 NORTHING 6049054 ZONE 14 DATUM NAD83
Date of mapping 07/26/1984

STRUCTURAL DATA

Layering:
Layering type | Strike | Dip | top Direction
bedding | 311 | 54 |

Planar Structures:
Structure type | Strike | Dip | Separation
schistosity | 251 | 76 |

Linear Structures
Type | Plunge | Azimuth
rodding | 53 | 43

PETROLOGIC DATA

Rock Number: 1

Rock Type: greywacke
Descriptors:
bedded
mafic
Field Description:

-hornblende rich seds. as to east with some ampb. horizons
-patchy feldspathic alteration

Minerals of Note
Mineral | Abundance (%)
hornblende
garnet

Rock Number: 2

Rock Type: sandstone
Descriptors:
massive
psammitic
Field Description:

-brownish grey weathering psammite to west of outcrop
-mostly 1 to 2 in massive lush with 10 to 20 cm semi-pelite interbeds
-patchy alteration to feld-HB on 2 to 5 cm scale

Rock Number: 3

Rock Type: pegmatite
Field Description:

-sampled extensivly by Anderson
-part of peristerite group
-not as much plag. as at 5643 dike but still significant
-has BO, some TC, lots of apple green apatite
-a few tiny opaques
-two textural phases--1) coarse plag. rich phaneritic
2) true peg, blacky perthitic microcline in peg-often graphic

Rock Number: 4

Rock Type:
Field Description:

-ALTERATION ZONE
-patchy material as at last with orange - pink garnet and some TL appears constrained to layering-may predate pegs
-appears to be aluminous alteration as amount of free quartz decreases sharply in the alteration patches

Minerals of Note
Mineral | Abundance (%)
garnet
tourmaline

Rock Number: 5

Rock Type: tonalite
Descriptors:
massive
leucocratic
Field Description:

-grey white 2 m thick massive intrusion
-intrusive into layering and folded by late foliation
-TL developed along contact with country rock
-pinches out to thin vein and then disappears going east
-relationship to pegs unclear as they don't cross but as it is intruding layering only and is then folded
-I suspect it predates pegs. significantly

Minerals of Note
Mineral | Abundance (%)
biotite
tourmaline

Manitoba Geological Survey, 2017