page 16. Total Paleozoic isopach map of northern Arizona ..... 17. Paleotectonic map of southern Cordillera, latest Precambrian to mid-Carboniferous (Mississippian-Pennsylvanian boundary) time, 625-325 myBP .......... 18. Paleotectonic map of southern Cordillera, mid-Carboniferous (Mississippian-Pennsylvanian boundary) to mid-Triassic (end of Middle Triassic) time, 325-225 myBP .