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A better understanding of intraplate deformation requires the knowledge of the space–time scales involved in its development and to decipher possible links with the dynamic evolution of the plate boundaries. Central Iran provides an ideal test site to approach this scientific issue, since it is characterised by a prolonged history of Mesozoic–Cenozoic intraplate deformation that has been interfering with the spatio‐temporal re‐organization of the Zagros convergence zone along the Eurasia plate boundary. This study focus on the Doruneh Fault (DF) region that is considered as the northern mechanical boundary of the Central East Iranian Microcontinent. By combining field investigations with apatite low‐temperature thermochronology, we present a revised tectono‐stratigraphic scenario for the DF region, typified by a punctuated history of fault‐related exhumation, burial and cooling history back to the Upper Cretaceous. When framed at regional scale, these results attest that the Zagros convergence zone, and its hinterland domain were fully mechanically coupled since ca. 40–35 Ma, a time lapse that is here referred as to the onset of continental collision along the Arabia–Eurasia plate boundary. In this scenario, the DF region operated throughout the Cenozoic as a major zone of residual stress accommodation and transfer in the hinterland domain of the Zagros convergence zone. Results of this study also suggest that the tectonic evolution along the Arabia–Eurasia plate boundary was modulated by the plate‐boundary dynamics and by the modes of tectonic reactivation of the intracontinental weak zones of Central Iran and at its tectonic boundaries. [ABSTRACT FROM AUTHOR]

• Most of the recent and probably fossil subduction zones on Earth are oblique. • Oblique subduction results in asymmetric mantle flow pattern leading to plate rotation. • Transition to continental subduction facilitates coeval trench advance and retreat. • Back-arc extension is led by toroidal mantle flow. • Sediments are transported in the trench and along the subduction interface. Most subduction zones on Earth are oblique, i.e., the angle between the plate convergence vector and the trench notably differs from 90°. Therefore, modeling and understanding the strain partitioning in the forearc, the development of extensional basins in the back-arc region and the diachronous transition from subduction to collision require a 3D approach. Here, we assess how oblique oceanic subduction and subsequent collision and associated mantle flow around the subducted lithosphere control the thermo-mechanical evolution of active margins. We conducted a series of 3D thermo-mechanical subduction models and discuss the influence of different subduction obliquity angles, the role of mantle flow variations and their connection with sediment transport and back-arc deformation. Numerical models are complemented by scaled analogue models to visualize the mantle flow evolution. Oceanic subduction along an oblique trench results in asymmetric mantle return flow leading to the gradual decrease of the subduction obliquity angle driven by the gradual rotation of the lower plate and the along-trench variation of slab retreat. This creates laterally variable subduction velocities and slab geometries. Back-arc extension is governed by both the toroidal mantle flow along the slab edges and by the oblique subduction induced lateral mantle flow gradient. The diachronous transition from oceanic to continental subduction and collision facilitates the laterally variable trench advance and retreat and back-arc deformation. Tectonically induced lateral sediment transport in the trench and along the subduction interface decreases its strength and viscosity and can alter subduction velocities. Our model results provide critical insights into the evolution of oblique subduction and collisional systems, such as the Arabia-Eurasia convergence zone. [ABSTRACT FROM AUTHOR]

We investigate the processes driving spatial-temporal patterns of Cenozoic exhumation in the Mediterranean and the Middle East by compiling >7300 published low-temperature thermochronometric ages and converting them into exhumation rates through a formal inversion process based on thermal modeling and closure temperature kinetics. Exhumation rates are resolved using piecewise-continuous spatial variability and timesteps of five million years. The spatial variability of the inferred rates is constrained by a plate tectonic reconstruction based on the integration of available kinematic data. In this model we recognize different tectonic blocks with a relative homogenous tectono-sedimentary and tectono-magmatic history. The inverted erosion rates for each block are then compared with regional and local geodynamic rates, eustatic curves, and climatic forcing to decipher common patterns and possible teleconnections among different blocks. The results document asynchronous exhumation across different tectonic blocks indicating local (i.e., at the scale of a single orogen) rather than regional (i.e., at the scale of multiple orogens) control on erosion rates. The main processes driving exhumation include collisions of Arabia, Adria, and Iberia with Eurasia, and subduction and retreat of the various Neo-Tethys slabs and back-arc basins. Specifically, we recognize two tectonic domains: collisional deformation zones where exhumation is controlled by surface uplift and erosion, and back-arcs areas where exhumation is controlled by tectonic denudation. In both cases we observe an increase in mean rates and rate variance during tectonic activity, followed by a decrease in each metric as tectonic activity wanes. Finally, we note (with a few exceptions) an overall increase in exhumation rates over most of the Mediterranean and Middle East in the last 5 Ma. This increase is more evident in areas of active tectonics and/or high topographic relief. Although we cannot exclude a tectonic contribution to some of these higher rates, the occurrence of higher exhumation rates, even in regions that did not experience enhanced tectonic activity, indicates that such an increase occurred most likely in response to the late Cenozoic global cooling and the Pleistocene increase in climate cyclicity. • We resolve Cenozoic exhumation rates in the Mediterranean and Middle East every 5 My. • An increase in mean erosion rates and their dispersion is associated with collision. • A decrease in mean erosion rates and their dispersion marks the end of deformation. • Quarternary climate-enhanced erosion is more evident in active tectonic and high relief areas. [ABSTRACT FROM AUTHOR]

The importance of slab–slab interactions is manifested in the kinematics and geometry of the Philippine Sea Plate and western Pacific subduction zones, and such interactions offer a dynamic basis for the first-order observations in this complex subduction setting. The westward subduction of the Pacific Sea Plate changes, along-strike, from single slab subduction beneath Japan, to a double-subduction setting where Pacific subduction beneath the Philippine Sea Plate occurs in tandem with westward subduction of the Philippine Sea Plate beneath Eurasia. Our 3-D numerical models show that there are fundamental differences between single slab systems and double slab systems where both subduction systems have the same vergence. We find that the observed kinematics and slab geometry of the Pacific–Philippine subduction can be understood by considering an along-strike transition from single to double subduction, and is largely independent from the detailed geometry of the Philippine Sea Plate. Important first order features include the relatively shallow slab dip, retreating/stationary trenches, and rapid subduction for single slab systems (Pacific Plate subducting under Japan), and front slabs within a double slab system (Philippine Sea Plate subducting at Ryukyu). In contrast, steep to overturned slab dips, advancing trench motion, and slower subduction occurs for rear slabs in a double slab setting (Pacific subducting at the Izu–Bonin–Mariana). This happens because of a relative build-up of pressure in the asthenosphere beneath the Philippine Sea Plate, where the asthenosphere is constrained between the converging Ryukyu and Izu–Bonin–Mariana slabs. When weak back-arc regions are included, slab–slab convergence rates slow and the middle (Philippine) plate extends, which leads to reduced pressure build up and reduced slab–slab coupling. Models without back-arcs, or with back-arc viscosities that are reduced by a factor of five, produce kinematics compatible with present-day observations. [ABSTRACT FROM AUTHOR]