Abstract:

 To a large degree, the intracontinental deformation is controlled by lateral rheological heterogeneities of lithosphere, and temperature (thermal gradient) is the major factor affecting the rheology of crust and mantle. The thermal weakening of crust/mantle rocks induced by heat represents a main way in rock weakening, which provides material condition for intracontinental deformation. Under the tectonic forcing (platerelated or nonplaterelated), these weakened rock materials are easily deformed and formed orogenic belt and deformation belt at continental interiors. This paper, based on the study of a great deal of relevant publications, introduces the thermal weakening of crust and mantle rocks caused by heatproducing element enrichment in the lithosphere and occurrence of strain localization and intracontinental deformation under the tectonic force produced by mantle downwelling induced by lithospheric mantle gravitational (RayleighTaylor type) instabilities.

Key words: heatproducing elements, thermal weakening, gravitational (RayleighTaylor type) instabilities, mantle downwelling, intracontinental (intraplate) deformation