Thermal models simulating the tectonic processes in the extra-Carpathian area (on the Romanian territory): Rheological models and their interpretation in relation with the local seismic wave attenuation models

Abstract

This study proposes a re-evaluation of the thermal models for lithosphere in the main tectonic units of the extra-Carpathian area (Central Moesian Platform, Black Sea Block and East-European Platform) and a minimization of the uncertainties in the spatial distribution of the parameters required in thermal modelling, by assimilation of available information supplied by tomographic seismic data, using the seismic wave velocity — temperature conversion. The thermal structures of the three tectonic compartments are estimated through the extrapolation of the surface heat flow determinations and by thermal modelling simulating the main geodynamic processes affecting the lithospheric structures (sedimentation in the Focsani Depression, magma eruption in the Neogene volcanic belt and convergence process in the Eastern Carpathians). Forcing the 1D and/or 2D thermal models (heat flow derived geotherms) to fit the seismic constraints (seismic derived geotherms) the more plausible values for the thermal parameters are assessed. The rheological structures in the investigated zones are then obtained by valuating the developed thermal models and are interpreted in correlation with the characteristics of the seismic wave propagation process — quality factor of the medium Q, provided by recent seismic studies.