Yellow bladerpod and Mexican Golden poppies carpet The Peridot Mesa vent is a part of the San Carlos volcanic field located in San Carlos, Arizona, USA on the San Carlos Apache Indian Reservation. The mesa is about 3 km (1.9 mi) in diameter and is capped by a basalt flow 3 to 6 meters thick that originated from a volcanic cone located in the Southwest corner of the mesa. The flow which surrounds this vent is of special interest to igneous petrologists due to several unique qualities including the extremely high concentration of xenoliths