KINEMATICS AND TECTONOTHERMAL MODELING - INTERPRETATION OF HEAT-FLOW OBSERVED ON THE TIBETAN PLATEAU

Thirteen heat flow values along a N-S profile are employed as surface constraints on a tectonothermal model of the Tibetan Plateau. The mode ling demonstrates 40 Ma of crust-mantle temperature-history, since the India-Eurasia collision. The main emphasis in this paper is put on th e fact that a series of heat-generating and heat-absorbing processes s uch as enhancement of radiogenic heating, strain- and friction-heating , partial melting etc., were induced by tectonic deformations of the l ithosphere. On this basis, equations defining terrane deformations in forms of shortening, thickening, extension, uplift and erosion were de duced using the principles of plate kinematics and 3-D mass balance. T hen, these equations being coupled with each other are further used as systematically defined initial and boundary conditions for integrated tectonothermal simulation. The modeling results suggest heterogeneity in lithospheric thermal structure and sharp differences in tectonothe rmal evolution between the old northern terranes and the new southern ones. However, even in the warm terranes in the south, the scale of th e tectonically induced heat-generating processes is smaller than usual ly expected.