Cenozoic Tectonics, Magmatism, and Stratigraphy of the Snake River Plain–Yellowstone Region and AdjacentYellowstone Areas plume themed trigger issuefor Basin and Range extension Yellowstone plume trigger for Basin and Range extension, and coeval emplacement of the Nevada–Columbia Basin magmatic belt Victor E. Camp1, Kenneth L. Pierce2, and Lisa A. Morgan3 1Department of Geological Sciences, San Diego State University, San Diego, California 92182, USA 2U.S. Geological Survey, Northern Rocky Mountain Science Center, 2327 University Way, Box 2, Bozeman, Montana 59715, USA 3U.S. Geological Survey, 973 Federal Center, Box 25046, Denver, Colorado 80225-0046, USA ABSTRACT and Range. It was not the sole cause of Basin Juan de Fuca–Farallon plates, tractional forces and Range extension, but rather the catalyst applied to the base of the lithosphere, buoyancy Widespread extension began across the for extension of the Nevadaplano, which was forces associated with lithospheric density varia- northern and central Basin and Range already on the verge of regional collapse. tions, and basal normal forces associated with Province at 17–16 Ma, contemporaneous mantle upwelling and/or gravitational insta- with magmatism along the Nevada–Colum- INTRODUCTION bilities. They concluded that boundary forces bia Basin magmatic belt, a linear zone of associated with plate interaction would produce dikes and volcanic centers that extends for The Basin and Range Province is one of the neither the magnitude nor the rates of extension >1000 km, from southern Nevada to the best exposed extensional areas in the world for observed in the northern and central Basin and Columbia Basin of eastern Washington. studying the effects and causes of large-scale Range, and that, at best, these forces can only This belt was generated above an elongated stretching of continental crust. The boundaries augment or modify the other forces necessary for sublithospheric melt zone associated with of this extended terrain were originally defi ned continental extension. They also concluded that arrival of the Yellowstone mantle plume, by the American physiographer N.M. Fenneman buoyancy forces have been the primary control with a north-south tabular shape attrib- (1928, 1931), with subdivisions defi ned by later for extension of the northern Basin and Range, uted to plume ascent through a propagat- workers. In this paper, the province is subdi- but that boundary forces might have played a ing fracture in the Juan de Fuca slab. Dike vided into northern, central, and southern seg- greater role in driving extension in the southern orientation along the magmatic belt suggests ments (Fig. 1), following the terminology of Basin and Range (Fig. 1). an extension direction of 245°–250°, but Jones et al. (1992) and Wernicke (1992). This quantitative approach led Sonder and this trend lies oblique to the regional exten- The Cenozoic extensional history of the Jones (1999) to attribute most of the extension sion direction of 280°–300° during coeval Basin and Range Province (Fig. 1) has been in the northern Basin and Range to gravitational and younger Basin and Range faulting, an explained through a variety of models, which potential energy, where crustal thickening and ~45° difference. Field relationships suggest include: (1) broadly distributed shear of the isostatic rise led to gravitational collapse of a high that this magmatic trend was not controlled plate interior driven by right-lateral motion of orogenic plateau (Dewey, 1988). Such a model by regional stress in the upper crust, but the Pacifi c plate (e.g., Atwater, 1970; Livaccari, is consistent with crustal shortening and the rather by magma overpressure from below 1979); (2) thickening of the crust suffi cient to development of fold-and-thrust belts in central and forceful dike injection with an orienta- produce buoyancy-driven extensional strain and eastern Nevada and western Utah during the tion inherited from a deeper process in the (e.g., Sonder et al., 1987; Jones et al., 1998); late Mesozoic to early Tertiary Sevier-Laramide sublithospheric mantle . The southern half or (3) subslab upwelling and lateral spreading orogeny. By the end of the Late Cretaceous, this of the elongated zone of mantle upwelling of asthenosphere, derived either from a “slab compressional regime had thickened the crust was emplaced beneath a cratonic lithosphere window” behind the trailing edge of the Faral- to an estimated 50–70 km (DeCelles, 2004; with an elevated surface derived from Late lon plate (e.g., Dickinson and Snyder, 1979), Best et al., 2013; Lechler et al., 2013), with a Cretaceous to mid-Tertiary crustal thicken- or from the adiabatic rise of the Yellowstone regional paleoelevation that was 3–4 km (e.g., ing. This high Nevadaplano was primed for mantle plume (e.g., Parsons et al., 1994; Saltus Chase et al., 1998; Wolfe et al., 1998; Chamber- collapse with high gravitational potential and Thompson, 1995; Pierce et al., 2002). lain et al., 2012). Gravitational potential energy energy under the infl uence of regional stress, Sonder and Jones (1999) evaluated these and variations appear to play the major role in exten- partly derived from boundary forces due to other models quantitatively by applying geologi- sion today, as suggested by the modeling results Pacifi c–North American plate interaction. cal and geophysical constraints on the driving of Flesch et al. (2000), Humphreys and Coblentz Plume arrival at 17–16 Ma resulted in advec- forces and the resisting forces inherent in each (2007), and Ghosh et al. (2013). tive thermal weakening of the lithosphere, model. They subdivided driving forces into four The effects of mantle upwelling (basal nor- mantle traction, delamination, and added groups: boundary forces associated with the rela- mal forces), however, are virtually indistin- buoyancy to the northern and central Basin tive motions of the Pacifi c, North American, and guishable from those produced by buoyancy Geosphere; April 2015; v. 11; no. 2; p. 203–225; doi:10.1130/GES01051.1; 9 fi gures. Received 7 March 2014 ♦ Revision received 30 October 2014 ♦ Accepted 17 December 2014 ♦ Published online 17 February 2015 For permissionGeosphere, to copy, contact April [email protected] 2015 203 © 2015 Geological Society of America Downloaded from http://pubs.geoscienceworld.org/gsa/geosphere/article-pdf/11/2/203/3332791/203.pdf by guest on 30 September 2021 Camp et al. 120°W 114°W Figure 1. The Basin and Range Province, with northern, central, and southern segments modifi ed from Jones et al. (1992) and 48°N Wernicke (1992). The northern and central Basin and Range are bounded to the west by the Sierra Nevada batholith and to the east by the Colorado Plateau. The northern Basin and Range incorpo- rates most of Nevada and western Utah. Its northern boundary is transitional with the Oregon High Lava Plains and the southern extension of the Columbia River Basalt Province, which contains the initial eruptions of fl ood basalt in the vicinity of Steens Moun- tain (SM). It also extends to the northeast, south of the Snake River Plain. Coeval extension north of the Snake River Plain is sometimes referred to as the Rocky Mountain Basin and Range (Sonder and Jones, 1999). Middle Miocene to Pliocene volcanic fi elds lying north of the northern Basin and Range include the Strawberry volcanics (STR) and the Lake Owyhee–Powder River volcanic fi eld (LOV- PRV). Metamorphic core complexes are located in the Snake Range (SR), the Albion–Raft River–Grouse Creek Ranges (ARG), and the 40°N Ruby Mountains–East Humboldt Range (REH). The Oregon-Idaho graben (OIG) is not typically considered part of the northern Basin and Range, although extension there was contemporaneous with mid-Miocene extension in north-central Nevada. The central Basin and Range incorporates the Colorado River extensional corridor of southern Nevada and adjacent California and Arizona. The south- ern Basin and Range lies southeast of the Sierra Nevada of southern California, extending eastward into the Sonora Desert of southern Arizona and southward beyond the confi nes of the map into Mexico. 0 300 Km forces associated with a thickened crust (Sonder and poorly constrained age correlations between of eastern Nevada and western Utah (ca. 165– and Jones, 1999). A vigorously upwelling the initiation of mantle upwelling and the timing 80 Ma), and the broader Laramide belt of block mantle would increase driving forces not only of extension in the northern Basin and Range. uplifts and structural basins in eastern Utah by increasing horizontal asthenospheric fl ow, There has also been a lack of interdisci plinary and Colorado (ca. 70–40 Ma) (e.g., Wyld et al., but also by warming the lithosphere, thus studies between workers with structural and 2003; Dickinson, 2013). By Late Cretaceous decreasing its strength, decreasing its densities, tectonic interests in the Basin and Range Prov- time, contraction in central and eastern Nevada and increasing lithospheric buoyancy. Simi- ince and those with geophysical and petrologi- had produced an overthickened crust (Coney, lar to crustal thickening, mantle upwelling can cal interests in mantle upwelling associated 1987), topographically expressed as a broad, generate dynamic topographic uplift and high with the Columbia Plateau–Snake River Plain– low-relief, high-elevation plateau. This elevated gravitational energy subject to normal faulting Yellow stone magmatic system. In an attempt to paleosurface has been called the “Great Basin over a wide region (Houseman and England, help bridge this gap, this paper reviews a broad altiplano” by Best et al. (2009), or the “Nevada- 1986). Thermorheological and thermomechani- range of studies from both of these regions that plano” by DeCelles (2004), analogous to the cal modeling suggests that a thickened crust appear to support a genetic relationship between present-day central Andean Altiplano of Bolivia may be unstable and may tend to collapse, but mid-Miocene mantle upwelling of the Yellow- and northern Argentina (Isacks, 1988).