Volcanics and neotectonic characteristics of the Springerville volcanic field, Arizona
L. S. Crumpler, Jayne C. Aubele, and C. D. Condit
The Plio-Pleistocene Springerville volcanic field (SVF) is one of the largest basaltic volcanic fields in the western U.S.. It is petrologically and volcanologically diverse and includes tholeiitic, alkalic and evolved alkalic rock types characterized by a general evolutionary trend in petrology in which tholeiitic rocks account for 24% of the field volume and were erupted early, and alkalic and evolved alkalic rocks (hawaiite, mugearite, and benmoreite) were erupted later. The average volume rate of effusion over the history of the field (1.5 X 10-4 km3/a) is similar to rates observed for other cinder-cone type volcanic fields throughout the world, but lower by about an order of magnitude than typical rates associated with large volcanic edifices and calderas. The magma supply in the Springerville volcanic field was long-lived, but too low and sporadic to sustain a single large volcano. Large-scale physiographic and morphologic features in the Springerville volcanic field reflect the kinematics of on-going, weak late Cenozoic, distributed tectonic deformations. The style, distribution and geometry of individual eruptions record the influence of contemporaneous tectonic stresses on the ascent and emplacement of magmas as well as environmental conditions present at the time of the eruptions. The general absence of strong patterns of fissure vents appears to be a consequence of the absence of regional tensile strain. Neotectonic structures are interpreted to indicate that left lateral shear stresses in the brittle crust occurred throughout much of the history of the Springerville volcanic field, rather than simple tensile stresses that would result in long fissures. Deeply penetrating faults in the northeast edge of the field interrupted the deep regional ground water flow and contributed to formation of spring deposits (travertine) in the northern margin of the field. The neotectonic deformation appears to record a transtensional style of lithospheric extension across this part of the southern margin of the Colorado Plateau in response to continued late Cenozoic clockwise rotation of the Colorado Plateau.
- Crumpler, L. S.; Aubele, Jayne C.; Condit, C. D., 1994, Volcanics and neotectonic characteristics of the Springerville volcanic field, Arizona, in: Mogollon Slope, west-central New Mexico, Chamberlin, Richard M.; Kues, Barry S.; Cather, Steven M.; Barker, James B.; McIntosh, William C., New Mexico Geological Society, Guidebook, 45th Field Conference, pp. 147-164.