Squirrel Springs Volcano-Tectonic Depression: A Buried Cauldron in Southwestern New Mexico
The Squirrel Springs depression is a 25-km-diameter structural basin in the northwest part of the Mogollon Plateau volcanic province, which is interpreted as the surface expression of a buried cauldron. Evidence for the buried cauldron includes (1) a shallow, terraced structural basin 25 km in diameter in which postcauldron volcanic rocks are ponded, (2) a circular fault pattern around the basin that is discordant with regional structural trends, (3) a porphyritic quartz latite dome complex centered within the basin, and (4) flow direction measurements showing flow of the Tularosa Canyon ash-flow tuff outward from the structure. The Squirrel Springs depression developed by (1) cauldron collapse accompanied by eruption of the Tularosa Canyon ash-flow tuff 30.7 m.y. ago, (2) burial of the cauldron by younger volcanic rocks, (3) reactivation of ring fractures forming a structural basin, and eruption of the John Kerr Peak Quartz Latite domes, and (4) arching of the northwest rim of the Mogollon Plateau, obscuring the western part of the Squirrel Springs depression.