Tectonics, lithology, and climate interaction in the landscape evolution of Talesh Mountain Range (NW Iranian Plateau)

The present-day landscape of the NW Iranian Plateau in the Arabia- Eurasia continental collision system results from the interplay between internal and external forces at different temporal scales. The Talesh Mountains along the NW margin of the plateau represent characteristics of a transient landscape that is the combined result of the spatial variability of rainfall, bedrock erodibility, and active tectonics. The erosion rates obtained from cosmogenic meteoric 10Be range from ⁓100 to 400 m/Myr, with lower values in the interior, and higher values in the plateau exterior which correlates with topographic metrics. Thermochronometry data and river inversion analysis from our 10Be erosion rates dataset, suggest that strain partitioning may have been active at least since ∼10 Ma. We can infer that during the last ~10 Ma a large wavelength process was synchronous with localized shortening and thickening in the Talesh Mts. The configuration of high precipitation, steepness values, millennial meteoric cosmogenic 10Be erosion rates, and longer-term exhumation rates in the eastern flank of the range probably started to develop during the last 10 Ma and led to the progressive coincidence of focused precipitation and tectonic activity. Such feedback may have been amplified during the ∼ 6 to 3-Myr-old base-level drop of the Caspian Sea. Consequently, we suggest possible long-term feedback among tectonics, topography, and surface processes/runoff variability in the Talesh Mts. The erosion rates are set by tectonic activity and the efficiency of these processes which are driven by climate, together with lithology control the orogenic architecture.