Cinder Hills Overlook - Sunset Crater National Monument, AZ
N 35° 22.286 W 111° 29.407
12S E 455478 N 3914344
Sunset Crater is the youngest in a string of volcanoes (the San Francisco volcanic field) that is related to the nearby San Francisco Peaks.
Waymark Code: WMTCBZ
Location: Arizona, United States
Date Posted: 11/01/2016
Views: 5
The date of the eruptions that formed the 340-meter-high cone (1,120 ft) was initially derived from tree-ring dates, suggesting the eruption began between the growing seasons of A.D. 1064–1065.[7] However, more recent geologic and archaeological evidence places the eruption around A.D. 1085.
The largest vent of the eruption, Sunset Crater itself, was the source of the Bonito and Kana-a lava flows that extended about 2.5 kilometers (1.6 mi) NW and 9.6 kilometers (6 mi) NE, respectively. Additional vents along a 10-kilometer-long fissure (6.2 mi) extending SE produced small spatter ramparts and a 6.4-kilometer-long lava flow (4 mi) to the east. The Sunset Crater eruption produced a blanket of ash and lapilli covering an area of more than 2,100 square kilometers (810 sq mi) and forced the temporary abandonment of settlements of the local Sinagua people. The volcano has partially revegetated, with pines and wildflowers. Since the last eruption of the volcano is a recent occurrence, it is considered dormant by volcanologists.
The San Francisco volcanic field is an area of volcanoes in northern Arizona, north of Flagstaff, USA. The field covers 1,800 square miles (4,700 km²) of the southern boundary of the Colorado Plateau. The field contains 600 volcanoes ranging in age from nearly 6 million years old to less than 1,000 years (Miocene to Holocene), of which Sunset Crater is the youngest.
The volcanic field seems to have formed from a geological hotspot, a hot area in the mantle. As the North American plate moves over the spot, new volcanoes appear. Thus, the newest volcanoes are at the east side of the field. Most of the volcanoes are basalt cinder cones, but there are also large lava domes consisting of rhyolite and dacite.
Given that Sunset Crater is such a young volcanic feature of this area and that eruptions have occurred every several thousands of years in frequency, it is likely that there will be a future eruption in the San Francisco Volcanic field. However, it is impossible to predict when and exactly where a new eruption might occur. The United States Geological Survey does say that a future eruption would likely be in the eastern side of the volcanic field, where the most recent volcanic activity has occurred. Such an eruption is likely to be small and pose little hazard due to the remoteness of the area.