Cross Lake Project (1983-86)

Geologist P.G. Lenton Year 83 STATION 5129
EASTING 575887 NORTHING 6041837 ZONE 14 DATUM NAD83
Date of mapping 07/10/1983

STRUCTURAL DATA

Dikes and Sills:
Rock Number | Type | Width (m) | Strike | Dip
1 | Molson dike | 0.00 | 236 | 77

PETROLOGIC DATA

Rock Number: 1

Rock Type: gabbro
Field Description:

Footwall section
-1a lower chill
-1b 6.5 m above lower contact - 2 pyroxene gabbro
-1c coarse leucocratic gabbro with cumulate layering 14 m. above footwall
-excellent cumulate features including scours and cross bedding
PHOTO 1 - contact between cumulous and leucocratic gabbro layers
PHOTO 2 & 3 - truncation of layers in cross bedded sequence
PHOTO 4 - truncation of layering in scour
PHOTO 5 - high angle truncation of layering by leucocratic gabbro
PHOTO 6 - reprosentative photo of leucocratic gabbro
PHOTO 7 - cross bed truncation
PHOTO 8 - lamination in magma tube
PHOTO 9 & 10 - over view of outcrop showing magnitude of cross bedding

PHOTOS

Contact between orthocumulate layer and leuco-gabbro layer.

Layer truncation in crossbedded sequence.

Larger view of previos layer trauncation.

Truncation of layering in a scour. Note the autolith below the scale card.

High angle truncation of layering by leuco gabbro.

Representativee photo of the leuco gabbro (anorthositic gabbro).

Crossbed truncation.

Lamination in a magma tube piercing thick bedded orthocumulate.

Overview of outcrop showing the scale of the crossbedding.

Manitoba Geological Survey, 2017