Late Cretaceous–Recent Low‐Temperature Cooling History and Tectonic Analysis of the Zuni Mountains, West‐Central New Mexico

Laramide tectonic models are testable with spatiotemporal constraints. The Colorado Plateau portion of the orogen, however, lacks detailed information on deformation timing. Herein, we analyze the Zuni Mountains, a Colorado Plateau Laramide arch, with apatite thermochronology, stratigraphic analysis, and thermal calculations to constrain and interpret its low‐temperature and tectonic history. Results show 2.9–3.6 km of pre‐exhumation burial by Late Cretaceous time that was sufficient to reset apatite (U‐Th)/He and apatite fission track dates after Pennsylvanian–Permian Ancestral Rocky Mountains exhumation. Low thermal conductivity of fine‐grained sediments was instrumental in facilitating sufficient temperatures to reset dates. Cooling histories of samples were structurally controlled. Forward and inverse models suggest ca. 80–45 Ma moderate to rapid cooling on the southwest flank and range crest of the arch, while the northeast flank displays 80–55 Ma slow cooling, very slow 55–20 Ma cooling and/or reheating, and post‐20 Ma rapid cooling. Northeast flank protracted cooling likely resulted from burial during backlimb tilting of the arch. Onset of exhumation was ca. 80 Ma, similar to 80–75 Ma onset of localized subsidence in San Juan Basin and 80–77 Ma onset of exhumation on the Nacimiento arch, but somewhat earlier than commonly considered for Colorado Plateau Laramide arches. In the regional context, our results support an easterly sweep of deformation driven by Farallon flat‐slab processes, and argues against prior suggestions for synchronous onset of Colorado Plateau Laramide deformation. Timing of post‐20 Ma cooling is most consistent with mantle‐driven epeirogenic uplift rather than Oligocene geotherm relaxation.