Bryson Burke Diamond Corporation: Diamond Exploration and Mining in Canada

Basalt and granite have quite a bit in common. Both are igneous rocks, which means that they cooled from a magma (the earth gets very hot just below the surface, and there is lots of liquid rock available). Both are made up of minerals from the silicate group, so both have large amounts of silica and oxygen. Both will hurt if you drop a big piece on your toe. But there are several important differences, too. These differences help define and explain how the earth works. Click GeoMan for more . . .

Pangea Index: The History of Continental Drift

We live on the Earth's Crust

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Grenville Province Crustal Structure

There are marked differences in the scale and disposition of the Archean blocks in western and eastern Quebec (Fig. AG-3). In western Quebec, the Archean block has a full crustal thickness of more than 40 km; that in eastern Quebec is only 30 km thick, with the balance of the crust being comprised of an upper, 10 km thick duplex of parautochthonous Meso-Proterozoic sedimentary rocks. We interpret the thinner Archean crust of eastern Quebec as part of the continental margin of the pre-Grenvillian continent that had been thinned by passive-margin formation. Unless there was substantial rethickening of the Archean crust in western Quebec during the Grenville orogeny, a possibility that is not supported by the apparent preservation of an early, northwest-pitching reflectivity, the Baskatong Promontory was unthinned Archean crust when it became involved in the Grenville orogeny. Regardless of the reason for it, the smaller thickness of Archean crust provides the simplest explanation for the greater thickness of preserved transported rocks in eastern Quebec than in western Quebec. (Click above for full article)