AGU Meeting, United States Of America, 1 - 04 January 2012
The Central Anatolian plateau is a distinct geologic area located between the Eastern Anatolian contractional province and the Western Anatolian extensional province. Existing geomorphological and geological data reveal that rapid uplift of more than ~1 km occurred during the last 7 Myr. Contemporaneously, extensional tectonics dominated the region and exhumation of metamorphic massifs (e.g., Nigde and Kirsehir massifs) occurred along the large-scale Tuzgolu normal fault. There is also a striking correlation between the low-velocity seismic zones beneath the crust and volcanic complexes (such as the Cappadocian Volcanic province), which could be interpreted to indicate that the plateau is underlain by hot/buoyant sub-lithospheric mantle, similar to the Eastern Anatolian plateau. In this work, we conduct a series of thermo-mechanical numerical experiments to examine quantitatively lithospheric delamination and dripping (or Rayleigh-Taylor) instability mechanisms for the evolution of the Central Anatolian plateau. More specifically, various rheological models of crust and underlying mantle are tested to explore the sensitivity of surface uplift (epeirogenic) responses to these properties. The model results are tested against a range of geological/geophysical observables (e.g., surface strain rate, surface elevation, crustal thickness) and syntheses of these results are reconciled with regional observational constraints. In particular, we focus on the present-day topographic signal, comparing the magnitude and pattern of observed dynamic topography in the region with flow models based on available seismic tomography inversions. As a result, we argue the case for a temporal and spatial coherence between the tectonics of lithospheric removal and associated vertical mantle flow beneath the Central Anatolian plateau.