Description:
The Sentinel Plains lava field and associated small shields are early Pleistocene-age, mantle-derived alkali
olivine basaltic lavas in the vicinity of the Gila Bend and Painted Rock Mountains, 65 km to 100 km
southwest of Phoenix, Arizona (please see 1:100,000-scale map). These volcanic centers are collectively
referred to as the Sentinel-Arlington Volcanic Field (SAVF). The SAVF covers ~600 km2 and consists of
more than 2 dozen volcanic centers ranging from 4-6 km in diameter and 30-200 m in height. The lavas
are partially eroded and dissected by peripheral ephemeral washes, the Hassayampa River, and the Gila
River, as well as lightly mantled by aeolian dust, pedogenic calcium carbonate, and basaltic rubble, with a
few areas covered by alluvium.