AGU Fall Meeting , California, United States Of America, 11 - 15 December 2023, pp.1
Orogenesis accounts for the formation of mountain belts and basins through plate boundary scale shortening and extension, over millions of years, based on average global tectonic strain rates (~10-9 yr-1). On the other hand, fast (a few million years) plateau uplift and surface subsidence, as well as strain localization, develop in hinterlands and continental interiors through mantle (convective) upwellings and downwelling. Specifically, delamination, break off, and convective removal are used to explain the development of short-lived geological events across Tethyan and Cordilleran orogenic systems. In this presentation, we provide a synthesis of geodynamic models of lithospheric removal that are reconciled with a series of geological, geophysical and petrological constraints. Delamination, slab peel-back (not roll back) can produce migratory and transient topography, with up to 2 km of uplift and 2 km of subsidence, adjacent to each other. For example, the east Anatolian plateau formed via subduction-accretionary process and the southeast Carpathian orogenic system are formed by slab peel-pack, subsequent to Neo-Tethyan subduction. Slab break-off drives the rapid rise of topography along the Alpine-Himalayan orogeny, for example in the central Apennines, but it cannot be held responsible for long-wavelength surface rise, such as the uplift of orogenic plateaus (Tibet, Anatolia). Mass balance estimates across the central Andean arc-back-arc and the Kırşehir arc of central Anatolia suggest lithospheric thickening and folding. Convective removal in the form of lithospheric drip tectonic models tested against paleoaltimetry and geophysical data from these regions show the punctuated nature of surface uplift (> 1 km) in less than 5 Myr. These drips are characterized by folding/wrinkle -like features along the crust while producing extension on the periphery and form circular shaped basins. Models for rapid loss of lithosphere are being increasingly invoked around the globe and other planetary bodies for their characteristic geological and geophysical signatures. Geodynamic experiments, when properly compared and contrasted against observations, are considered to be key agents to address the primary role of lithospheric removal in the orogenic cycle.