Rheological Heterogeneities Control the Non‐Progressive Uplift of the Young Iranian Plateau.

The Iranian plateau is at the early stage of plateau development and intracontinental deformation in response to the Arabia‐Eurasia collision. Its compressive deformation is concentrated in the northern plateau but skips the central counterpart, challenging the common views envisaging the progressive uplift from the collisional front to the hinterland. Based on three‐dimensional, crustal‐scale numerical models, we present how the rheological heterogeneities common in continents control the deformation of the young Iranian plateau. The weak northern plateau ensures itself a preferential zone in accommodating continental collision. The N‐S strike‐slip faults within the non‐rigid central plateau, formed along the boundaries between the tectonic units with rheological contrast, suppress the shortening of the central plateau while further accentuating the compressive deformation of the northern plateau. Our results suggest a non‐progressive intracontinental deformation pattern where rheological boundaries and mechanically weak zones, not necessarily those close to collisional fronts, preferentially accommodate continental convergence. Plain Language Summary: Continental collisions can produce extensive intracontinental deformation and uplift, forming orogenic plateaus. Common views predict progressive plateau uplift from the collisional front to the hinterland. In the young Iranian plateau, however, uplift mainly occurs in its northern and southern (collisional front) boundary zones while its central part shows relatively low elevation. Here, we perform numerical modeling experiments to investigate the deformation and uplift mechanisms of the Iranian plateau, which can promote our understanding of plateau evolution. The models show that only when the northern plateau is weaker than the central counterpart, uplift will preferentially occur in the north. The central plateau, which displays minor compressive deformation and uplift, is not necessarily rigid. The large‐scale N‐S strike‐slip faults in this region that developed along the boundaries between tectonic blocks with strength contrast can facilitate compressive deformation to concentrate on the northern plateau, making the central plateau less uplift. The results suggest that rheological boundaries and mechanically weak zones, not necessarily those close to collisional fronts, deform preferentially to accommodate continental convergence. Therefore, we suggest a non‐progressive intracontinental deformation pattern, since orogenic plateaus are usually composed of multiple tectonic blocks with different properties. Key Points: 3D crustal‐scale models investigate the strain partitioning and non‐progressive uplift of the young Iranian plateauRheological heterogeneities and large‐scale strike‐slip faults jointly dominate the intracontinental deformationRheological boundaries and mechanically weak zones preferentially accommodate continental convergence [ABSTRACT FROM AUTHOR]