Labrador

Labrador has a fabulous diversity of geology. It has rocks as old as 3.8 billion years old to the present. In addition to rocks, Labrador also is known for:
 
Bears…
Wide expanses of pine trees…
Blueberries!
 
Most of the best exposures in Labrador are to be found in quarries. These quarries are large scars in the landscape nearly fifty feet deep and hundreds of meters wide. Because these quarries are less than 50 years old there has been little to no weathering resulting is excellent outcrop.


Left: garnet-bearing, K-feldspar megacrystic biotite granitoid rock with ovoid megacrysts. Right: mafic dike associated with the 615 Ma Long Range dike swarm with small quenched plagioclase phenocrysts.
Wouter Bleeker testing the magnetic susceptibility of the Long Range dike.
Top to the right shear fabric in a K-feldspar megacrystic granitoid from the Lake Melville terrane.
Biotite and K-feldspar pegmatite with 1 meter wide biotite crystal.
graphite+quartz+K-spar+biotite+titanite gneiss
Think of it graphite in a granitic gneiss!
More graphite.
This excellent specimen of fergusonite [(Y, rare earths)NbO4] found on HighREE Island. That’s right High Rare Earth Element Island. The island was named by the mining company Search Minerals because of the bizarre occurrence of rare earth elements. Rare earth mineralization is found primarily in pegmatite and aplite intrusions. The rare earth elements were discovered by prospectors walking around with geiger counters. When the geigers click the prospectors dig.
More fergusonite in a pegmatitic dike.
Allanite [(Ce,Ca,Y,La)2(Al,Fe+3)3(SiO4)3(OH)] crystal in pegmatite intruding the Alexis River Anorthosite/Leucogabbonorite. The radial fractures around the allanite are formed from radiation damage.
On top of all the crystalline rocks is the Cambro-Ordovician rocks of the Sauk transgression (the Labrador group). From Estonia to Scotland, Labrador, Argentina, Texas, California, Yukon, and the Northwest Territories all display this same sequence of rocks.

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