Petrologic, paleomagnetic, and structural evidence of a Paleozoic rift system in Oklahoma, New Mexico, Colorado, and Utah

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“…Within southern Oklahoma, the Wichita uplift-Anadarko basin system formed as a result of late Mississippian-Pennsylvanian ARM compression that inverted the failed Cambrian rift (Larson et al, 1985;Gilbert, 1992). The inversion structures are unusually large, with at least 12 km of vertical separation between the Cambrian basement exposed in the Wichita Mountains and that present in the subsurface of the adjacent Anadarko basin (Perry, 1989;Keller and Stephenson, 2007).…”

“…Notably, Larson et al (1985) suggested that the SOA extended to the Uncompahgre uplift region of Colorado on the basis of distributed, but limited, Cambrian mafi c intrusives. Recent geophysical studies corroborate this inference (e.g., Smith, 2002;Casillas, 2004;Rumpel et al, 2005;Keller and Stephenson, 2007;Pardo, 2009; details in the following).…”

An integrated analysis of controlled and passive source seismic data across an Archean‐Proterozoic suture zone in the Rocky Mountains

“…Mafic intrusions of Cambrian age are found in the Wet Mountains [e.g., Larson et al, 1985] and recent gravity studies [Pardo and Keller, 2008] indicate that that a large mass of this age is the explanation of the high velocities observed. The South Park basin begins just north of the Wet Mountains and Precambrian basement and late Eocene intrusive rocks of the Colorado Mineral belt terminate this basin at $550 km along the model and separate it from the Middle and North Park basins.…”

“…This feature is one of a series of uplifts and basins that formed in the late Paleozoic during the Ancestral Rocky Mountain orogeny [e.g., Kluth and Coney, 1981]. However, this feature is also associated with a large northwest trending gravity high and has been interpreted to be part of a Cambrian rift zone along which many large mafic intrusions were emplaced [e.g., Larson et al, 1985;Keller and Stephenson, 2007].…”

Detrital zircon geochronology of the Grenville/Llano foreland and basal Sauk Sequence in west Texas, USA

“…1) and is bounded by the Wichita, Sierra Grande, Cimarron, Tusas, and Uncompahgre uplifts (McMillan and McLemore, 2004;Keller and Stephenson, 2007). Extensive exposures of Cambrian-age bimodal igneous rocks within the Oklahoma-Colorado aulacogen indicate that crustal extension (Larson et al, 1985;McMillan and McLemore, 2004;Gilbert and Hogan, 2010) propagated broadly cratonward with ages ranging from 539 Ma to 528 Ma, based on laser ablation (LA)-ICP-MS and ID-TIMS U-Pb zircon geochronology (Larson et al, 1985;Lambert et al, 1988;Hames et al, 1995;Hogan and Gilbert, 1998;McConnell and Gilbert, 1990;McMillan and McLemore, 2004). In southwestern New Mexico, the Florida Mountains pluton has also been dated by zircon U-Pb geochronology as crystallizing at ca.…”