ON THE THERMAL REGIME OF SOME TECTONIC UNITS IN A CONTINENTAL COLLISION ENVIRONMENT IN ROMANIA

An analysis of the evolution of the main tectonic units in Romania shows that the thermal regime of the lithosphere should be derived according, on the one hand, to the particular tectonic interactions the various tectonic units have been involved in and, on the other hand, to the investigated depth interval. A steady-state conduction model of the crustal temperature field based on the heat flow distribution and information on the structure is presented for the Romanian territory. It shows large lateral thermal variations between tectonic units, as a result of different geological and thermal histories. Within the frame of a complex modelling of the thermal evolution of the lithosphere in the East Carpathians, as proposed in this study, the zero-order thermal effects of the pre-Miocene oceanic subduction of the Eurasian plate are evaluated. The deep thermal structure of the subducted slab is derived and shown to be compatible with the velocity structure of the lithosphere and the intermediate-depth seismicity of the Vrancea area.