15—Anorthosite—Shore of Lake Michikamau.
A coarse grained rock of dark gray color, in which labradorite is the chief mineral. Magnetite and Kaolin are present in small quantities.
The labradorite contains inclusions of rutile and biotite and has a well-developed wedge structure and cross fracture due to the pressure and shearing which it has undergone.
It is also somewhat stained by the decomposition of the magnetite.
SOURCES OF INFORMATION
On the map of the portage route to Lake Michikamau; that lake, the Grand River and Groswater Bay are taken from the map accompanying the report of Mr. A. P. Low.
The location of the Susan and Beaver Rivers with their tributaries was obtained from Dillon Wallace’s map in “The Lure of the Labrador Wild.”
The instruments used were a Brunton Pocket Transit, a small taffrail log and an Aneroid Barometer. Distances on land were approximated by means of a pedometer and by rough triangulation.
