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The Andean Plateau of north‐western Argentina (Puna) at a mean elevation of ca. 4.2 km constitutes the southern continuation of the Altiplano; it is a compressional basin‐and‐range province comprising fault‐bounded, high‐elevation mountain ranges and largely internally drained basins with often thick sedimentary and volcaniclastic fill. Growing sedimentological and structural evidence supports the notion that the north‐western Argentine Andes between 22° and 26°S developed from an initial extensive broken‐foreland system that extended across the present‐day eastern Andean flank during the early to middle Eocene. However, compelling evidence of the tectonic history of this region is still missing. Here, we present new apatite fission track and zircon (U–Th)/He thermochronological data and U–Pb zircon ages from intercalated volcanic ash deposits from the Pastos Chicos Basin (23.5°S, 66.5°W) to constrain basin formation and the timing of major crustal deformation in the northern Puna. Inverse thermal modeling of the thermochronological data provides further temporal constraints on the late Cenozoic cooling history of the crust in this region and, by inference, on the timing of upper‐crustal shortening, range uplift, and basin formation in the northern sector of the present‐day Puna Plateau. Specifically, we argue for plateau‐wide distributed deformation in the Eocene between 23° and 24°S, followed by spatially disparate and diachronous deformation (Oligocene to Pliocene)., Plain Language Summary: The Argentine Puna Plateau is a mountainous region in the Central Andes of South America. It is the result of the tectonic convergence between the oceanic Nazca Plate and the continental South American Plate. However, the detailed tectonic evolution of this region is yet unknown. We present new thermochronologic data from the Puna Plateau that allow inferences about crustal deformation and mountain range uplift. Combined with previous studies, our results suggest deformation distributed over the entire plateau during the Eocene. Thereafter, local deformation occurred spatially non‐systematic, possibly related to zones of weakness in the crust., Key Points: Thermal modeling of apatite fission track and (U‐Th)/He zircon data from the Pastos Chicos Basin shows Oligo‐Miocene onset of exhumation. Regional compilation of spatio‐temporal deformation at 23°–24°S suggests out‐of‐sequence deformation related to basement heterogeneities. Mio‐Pliocene U–Pb zircon ages of volcanic ash deposits refine the chronostratigraphy of the Pastos Chicos Basin., Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659, Brandenburg Ministry of Sciences, Research and Cultural Affairs, Germany, Blaustein Fund, Fulbright Foundation, France‐Stanford Center for Interdisciplinary Studies, https://doi.org/10.6084/m9.figshare.20209865.v1

Supplementary text: Analytical methods.

Cenozoic tectono-magmatism in Iran is widely considered to be related to subduction of the Neo-Tethys Ocean. We employed whole-rock and mineral geochemistry and isotopic data of intrusive rocks from Tafresh, central Urumieh-Dokhtar magmatic arc, to evaluate the role of the mantle in magmatism, to assess the timing of emplacement, and to interpret the tectonic setting. Rock compositions range from gabbro or gabbro-diorite (plagioclase + pyroxene ± olivine), to diorite (plagioclase + amphibole ± pyroxene), to granodiorite (quartz + plagioclase + K-feldspar + amphibole + biotite), exhibiting high-alumina calc-alkaline affinity. Major oxide and trace element variations vary systematically from less to more evolved rocks suggesting a major role for fractional crystallization processes. Zircon LA-ICP-MS U–Pb ages of major rock types are in the range of 24–19 Ma, whereas those of gabbroic dikes are ~17.5 Ma. ԐNd values range between -1.8 and 3.7, and (87Sr/86Sr)i is narrowly restricted to 0.705–0.706, suggesting a common mantle source. The enrichment in light rare earth element (REE) enrichment and flat heavy REE patterns couple depletion of Nb–Ta–Ti indicate that subducting oceanic crust had interacted with the overlying mantle wedge. High-alumina, mid-Mg# Tafresh plutonic rocks formed from hydrous melts from which Ca-pyroxene and magnetite crystallized earlier than plagioclase, whereas late-crystallizing zircon nucleated while magma traversed through lithospheric mantle and Cadomian crust. Modelling of isotope and incompatible-element patterns suggests the contribution of no more than ~5% molten sediment or other crustal components in Tafresh magma, at a developmental stage before most plagioclase and amphibole had crystallized. The Miocene Tafresh plutons originated during the final stages of subduction, before the collision between the Arabian and Eurasian plates.