^There is a "difference between the geophysical and geological definition of suture zones and terrane boundaries. The geophysical definitions are generally based upon the integration of a physical response over the thickness of the crust, whereas the geological definition is almost always as a line or zone at the Earth's surface." Harris, Anthony L. and Fettes, D. J. (1988) The Caledonian-Appalachian orogen published for the Geological Society by Blackwell Scientific Publications, Oxford, England, page 4, ISBN978-0-632-01796-6
