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Geologic evidence across orogenic plateau margins enables the discrimination of the relative contributions of orogenic, epeirogenic and/or climatic processes that lead to growth and maintenance of those plateaus and their margins. Here, we discuss the mode of formation of the southern margin of the Central Anatolian Plateau (SCAP) and evaluate its time of formation using fieldwork in the onshore and seismic reflection data in the offshore. In the onshore, uplifted Miocene rocks in a dip‐slope topography show monocline flexure over >100 km, km‐scale asymmetric folds verging south, and outcrop‐scale syn‐sedimentary reverse faults. On the Turkish shelf, vertical faults transect the basal latest Messinian of a 10 km fold where on‐structure syntectonic wedges and synsedimentary unconformities indicate pre‐Pliocene uplift and erosion, followed by Pliocene and younger deformation. Collectively, Miocene rocks delineate a flexural monocline at plateau margin scale that is expressed along our on‐offshore sections as a kink‐band fold with a steep flank 20–25 km long. In these reconstructed sections, we estimate a relative vertical displacement of 3.8 km at rates of ca. 0.5 mm/y, and horizontal shortening values <1 %. We use this evidence together with our observations of shortening at outcrop, basin, plateau‐margin and forearc‐system scales to infer that the SCAP forms as a monoclinal flexure to accommodate deep‐seated thickening and shortening since >5 Ma, and to contextualize the plateau margin as the forearc high of the Cyprus subduction system. [ABSTRACT FROM AUTHOR]

• Models show a mechanism where forearc sediments thermally activate deep crustal flow. • Viscous flow changes regional subsidence into short-wavelength uplift/subsidence. • Forearc high uplift is controlled by sediment accretion, sedimentation and temperature. • Mechanism explains S Anatolia upper-plate strain and vertical motions in Neogene. • Mechanism explains S Turkey uplift by accretion and viscous flow, not slab break-off. We present a model for the dynamic formation of the forearc high of southern Anatolia where sedimentation in the forearc basin leads to thermally-activated deformation in the lower crust. Our thermo-mechanical models demonstrate that forearc sedimentation increases the temperature of the underlying crust by "blanketing" the heat flux and increasing Moho depth. Deformation switches from frictional to viscous with a higher strain rate led by increased temperature. Viscous deformation changes large-wavelength subsidence into coeval, short-wavelength uplift and subsidence. Models show that forearc highs are intrinsic to accretionary wedges and can grow dynamically and non-linearly at rates dependent on sediment accretion, sedimentation and temperature. The mechanism explains the uplift of the southern margin of the Central Anatolian Plateau and the Neogene vertical motions and upper-plate strain in the Anatolian margin along Central Cyprus. This system is analogous to forearc highs in other mature accretionary margins, like Cascadia, Lesser Antilles or Makran. [ABSTRACT FROM AUTHOR]