Factors controlling the rift basin formation in the Black sea region inferred from geodynamic models

Geodynamic modeling studies have shown that rift basin formation and their transition to sea floor spreading is controlled by tectonic deformation and surface processes. Furthermore, models are used to identify the controlling factors of symmetric vs asymmetric characteristics of the rift basins and the fault network patterns. Here, we use Black sea rift basin as a case study to test how varying model parameters can help to understand rapid subsidence and crustal stretching as well as up to 14 km of sediment thickness in the region. Namely,  we use high-resolution 2D geodynamic models (ASPECT) coupled with a landscape evolution code (FastScape) to investigate rift development under changing model parameters. We also reconcile model results against a number of geological and seismic reflection data where different types of stretching modes, such as pure vs simple have been described in the eastern and western sub basins. Our geodynamic model results provide important insight into how rifting has evolved in the black sea where thick sedimentary deposits are accumulated and possibly delayed continental break up.  That is, the thick sedimentary cover (Maykop) probably impeded serpentinization (sediment blanket) by modifying thermal structure of the crust. Models also explain the pure shear stretching (basin symmetry) in the eastern sub-basin compared to the west where migration of rift axis has been suggested and causing a broad zone of hyperextended crust.