The Valley and range sequence-Southern Yuma County is a 3-Valley sequence of NW–by–SE trending block faulted valleys and mountains. About eleven major mountain ranges connect to each other in four, (mostly parallel), mountain sequences.
This regional parallel valley-mountain sequence ends at the Gila River valley at the north; to the south, it extends to the Gran Desierto de Altar of northwestern Mexico; the sequence is a remnant of the Basin and Range system.
List of valleys Coyote Wash and Lechuguilla Desert Mohawk Valley (Arizona) San Cristobal Valley
Table of mountain ranges The three valleys lay mostly between these perimeter mountain sequences. West SequenceNorthW-Central blockE-Central blockEast SequenceNorthGila River ValleyGila River ValleyGila River ValleyGila River ValleyGila Mountains (Yuma County)Wellton Hillsand Baker PeaksMohawk MountainsAztec HillsGila Mountains (Yuma County)Copper MountainsMohawk MountainsAguila MountainsTinajas Altas Mountainsand Butler Mountains)W:Cabeza Prieta and Tule MountainsE:Sierra PintaBryan Mountainsand Antelope HillsGranite Mountains (Arizona)Tinajas Altas Mountainsand Butler Mountains)W:Cabeza Prieta and Tule MountainsE:Sierra PintaBryan Mountainsand Antelope HillsxxxxxxWest SequenceSouthW-Central blockE-Central blockEast SequenceSouth
See also Fault-block mountain
External links U.S. Bureau of Reclamation: Map of "Surface geology of the Lower Colorado River Planning Area" – Southwestern Arizona. ADWR – Arizona Dept of Water Resources: Lower Colorado River Hydrology – with map