Thermo-mechanical controls on intraplate deformation and the role of plume – folding interactions in continental topography

Abstract

Thermo-tectonic age and inherited structure exert the main controls on the bulk strength of the lithosphere in intraplate settings. Mechanical decoupling within the lithosphere strongly affects the interaction between deep Earth and surface processes. Thermo-mechanical models demonstrate the particular importance of the rheological stratification of the lithosphere in the preservation of ancient cratonic blocks, in the surface expression of plume- and mantle lithosphere interactions and their impact on the “dynamic” topography in general. The same is true for the effect of large-scale lithospheric folding on intraplate basin formation and associated differential vertical motions. Initiation of continental lithosphere subduction, crucial for linking orogenic deformation to intraplate deformation, appears to be facilitated by plume–lithosphere interactions. We present a discussion of these aspects, focusing on better process- understanding of continental deformation, in the context of a number of well-documented cases of intraplate deformation.