Patterns of volcanism along the southern margin of the Colorado Plateau: The Springerville Field

Abstract

The mostly 2.1‐ to 0.3‐m.y.‐old Springerville volcanic field is the southernmost of the Colorado Plateau‐margin fields and encompasses −3000 km2, with a volume of −300 km3. Mapping documents 409 flow units, most emanating from one of the −400 predominantly pyroclastic cones. Alkali olivine basalt constitutes about one‐half the outcrop area, with hawaiite and tholeiite each composing about a quarter of the area, and mugearite and benmoreite each covering less than 1% of the area. The composition of the lavas shows a progression away from tholeiitic and toward alkalic affinities with decreasing age, in marked contrast to that found in both the southeast and western margins of the Colorado Plateau. Estimates of volume effusion rates show an early eruptive episode dominated by large volumes of tholeiitic lavas, a middle period of alkali olivine basalt eruption, and a late pulse of evolved alkalic rocks. Changes in chemistry [Na2O + K2O, MgO/(MgO + FeO*), K/P] with respect to location of lava sources that might reflect thermal and/or chemical differences appear to be minimal. Eastward migration of alkali olivine basalt volcanism within the Springerville volcanic field is essentially identical to that seen in the San Francisco volcanic field for the same time period, supporting the suggestion of Tanaka et al. (1986) that it may reflect the westward motion of the North American continent above relatively fixed mantle sources. The late Cenozoic migration of volcanic fields toward the Colorado Plateau suggested by Best and Hamblin (1978) and by Luedke and Smith (1978) does not seem to be reflected by vent migrations from 2.1 Ma to the present within the Springerville and San Francisco fields.

Hazard area and probability of volcanic disruption of the proposed high-level radioactive waste repository at Yucca Mountain, Nevada, USA

“…Volcanic fields commonly migrate or expand and new volcanoes generally erupt at the periphery of an existing field. Patterns of volcanism are complex and shifts or migration in the location of volcanism over periods of million of years have been documented in many basaltic volcanic fields: Examples include the Coso Volcanic Field in California (Duffield et al 1980;Condit et. al 1989); San Francisco Volcanic Field in Arizona (Tanaka et al 1986); Lunar Crater Volcanic Field in Nevada (Foland and Bergman 1992); Michoacán-Guanajuato Volcanic Field in Mexico (Hasenaka and Carmichael 1985); and Cima Volcanic Field in California (Dohrenwend et al 1984;Turrin et al 1985).…”

Mafic alkalic magmatism in central Kachchh, India: a monogenetic volcanic field in the northwestern Deccan Traps

“…Such fields typically form in areas experiencing low rates of magma production, with little or no crustal extension (Condit et al 1989;Valentine and Hirano 2010). They may develop on the flanks of large stratovolcanoes or shield volcanoes, as satellite vents that can number into hundreds.…”

Systhesis of Volcanism Studies for the Yucca Mountain Site Characterization Project

“…Perhaps the best documented example of systematic volume and compositional relationships through time is the Springerville volcanic field on the southern Colorado Plateau margin of Anzona (Condit et al, 1989). At Springerville, the earliest and most voluminous basalt is tholeiitic (large degree of partial melting), which erupted between 6.5 and 1.75 Ma (Condit et al, 1989;.…”