10.6084/m9.figshare.3454829.v1 Yanni Gunnell Yanni Gunnell Jean-Claude Thouret Jean-Claude Thouret Stéphanie Brichau Stéphanie Brichau Andy Carter Andy Carter Kerry Gallagher Kerry Gallagher Low-temperature thermochronology in the Peruvian Central Andes: implications for long-term continental denudation, timing of plateau uplift, canyon incision and lithosphere dynamics Geological Society of London 2016 plateau magmatism rock cooling histories 24 Ma canyon thermochronology rock heating event Peruvian Central Andes uplift incision middle Miocene time response denudation subducting slab dynamics km Geology 2016-06-21 12:22:48 Dataset https://geolsoc.figshare.com/articles/dataset/Low-temperature_thermochronology_in_the_Peruvian_Central_Andes_implications_for_long-term_continental_denudation_timing___of_plateau_uplift_canyon_incision_and_lithosphere_dynamics/3454829 <p>In Peru, the western edge of the 4.5 km high Western Cordillera is cut by a >3 km deep canyon. To understand incision by the Cotahuasi–Ocoña River and the regional uplift history of this orogenic plateau capped by volcanic rocks, 26 crystalline rock samples were collected for low-temperature thermochronology from vertical profiles parallel and perpendicular to the canyon. Rock cooling histories confirm that most plateau denudation had occurred prior to 24 Ma but plateau incision peaked after <em>c</em>. 14–9 Ma in response to rapid surface uplift. The abrupt occurrence of a rock heating event is also detected during middle Miocene time. This was either a response to the emplacement of low-conductivity, regionally extensive ignimbritic caprock or a response to crustal-scale fluid circulation caused by wet melting of the overriding plate when magmatism resumed <em>c</em>. 24 Ma. The potential for thermochronology to provide information on past geothermal gradients is discussed, showing how it can be used as a proxy for understanding change in subducting slab dynamics, with oscillations in subduction angle having perhaps been the main on–off switch for magmatism in this Cordilleran setting. </p>