Architecture of kinematics and deformation history of the Tertiary supradetachment Thrace basin (NE Greece)

Detailed tectonic analysis on the Tertiary molassic and volcanosedimentary rocks of the Thrace basin allowed us to reconstruct the architecture and structural evolution of the basin, as well as the orientation of the regional paleostress field. The Tertiary molassic sedimentation of the Thrace basin was linked by a calc-alkaline magmatism associated with the Tertiary syn-orogenic extension in the Rhodope province. The Thrace basin was initially developed on the hanging wall of a low angle extensional detachment fault system of Mid- Late Eocene age simultaneously with uplift and exhumation of the Rhodope metamorphic rocks in the footwall. We interpret the molassic Tertiary Thrace basin as a supra-detachment basin associated with intense magmatism. Five (5) deformational events (T1 to T5) have been distinguished related to the basin evolution from Eocene to Quaternary time. T1 is related to low angle normal detachment faults with a mainly toward SW to SSW sense of movement of the tectonic top and subsidence of the initial Thrace basin during Mid-Late Eocene time. T2 is evolved during Oligocene-Miocene time. It is characterized by transpressional tectonic and formation of big strike slip faults and extensional fractures, as well as conjugate thrust faults and folds with N or S to NW or SE sense of movement. During Miocene-Pliocene the third T3 event is taken place. It is responsible for the high angle normal fault dismembered the Eocene-Oligocene molassic basin into Neogene grabens. A local T4 event has been recorded affecting also the Neogene sediments of the basin with minor reverse strike slip faults as well as normal faults. The following T5 event is related to big normal active faults. They are coincided to the active tectonic of the study area defined by the earthquake focal mechanisms.