WESTERN NORTH AMERICA SHOWS HOW CONTINENTS GROW WITH TIME AS MATERIAL ACCRETES TO THEIR EDGES

-BLOCKS THAT HAVE BEEN ADDED ARE CALLED TERRANES

-THESE INCLUDE VOLCANIC ARCS, CONTINENTAL FRAGMENTS, AND OLD SEA FLOOR (OPHIOLITES)

-THESE ARE IDENTIFIED BY GEOLOGICAL MAPPING AND PALEOMAGNETIC STUDIES

-MAP SHOWS BLOCKS ADDED IN PAST 300 MYR