Tectonic Models for the Evolution of Sedimentary Basins

Abstract

The tectonic evolution of sedimentary basins is the intrinsic result of the interplay between lithospheric stresses, lithospheric rheology, and thermal perturbations of the lithosphere–upper mantle system. The thermomechanical structure of the lithosphere exerts a prime control on its response to basin-forming mechanisms, in both extension and compression. Tectonic reactivation has strongly affected the structure and fill of many sedimentary basins. The long-lasting rheological memory of the lithosphere appears to play a far more important role in basin reactivation than hitherto assumed. The temporal evolution of the strength of continents and the spatial variations in stress and strength at continental margins, rifts, and orogenic belts govern the mechanics of basin development in time and space. Polyphase deformation is a common feature of many sedimentary basin systems. Compressional reactivation of extensional basins during their postrift phase appears to occur in many intraplate rifts and passive margins, reflecting temporal and spatial changes in the orientation and magnitude of the intraplate stress regime. Similarly, foreland basins are frequently characterized by preorogenic extension. The actual subsidence patterns of these polyphase systems are often more complex than predicted by end-member models that only consider the basin formation mechanism. Folding of the lithosphere, involving positive and negative deflections, appears to be of more importance in the large-scale deformation of intraplate domains than hitherto realized. In the intraplate domain of continental Europe that was thermally perturbed by Cenozoic upper mantle plume activity, lithospheric folding, for instance, plays an important role and strongly affects the pattern of vertical motions, in terms of both the basin subsidence and the uplift of broad arches. Tectonic processes operating during basin formation and during the subsequent deformation of basins can generate significant differential topography in basin systems. In view of the close link between erosion of topographic highs and sedimentation in subsiding areas, constraints are needed on uplift and coeval subsidence to validate quantitative process-oriented models for the evolution of sedimentary basins. Integration of analog and numerical modeling provides a novel approach to assess the feedback mechanisms between deep mantle, lithospheric, and surface processes.