The tar sands underlie much of Alberta's subarctic boreal forest, an environment of coniferous woodlands, muskeg bogs, lakes, rivers and marshes. Although summer days are long, the growing season is ...

The two countries both produce heavy oil, which is difficult to refine, and have relied historically on American refineries ...

Canada and Venezuela compete in the same heavy-oil regional and global markets, so shifts in supply from Canada to Venezuela ...