If it is really Canadian Shield (granite), OK, but, if not, make sure you are not buying / building on Quick Clay. (See Wikipedia article.)

Highway 416 between Prescott and Ottawa crosses over some unstable stretches, and you don't want to have your house collapse like what happened to a family living in St Jude, Qc on May 11, 2010. They had a nice, solid looking rural house, and it slid into a void, killing them all.