On the mechanics of lithospheric stretching and doming: a finite element analysis

Abstract

To investigate the thermo-mechanical aspects of lithospheric thinning and rift formation we have constructed finite element models for doming and stretching. We have found that the magnitude of stretching forces required to induce failure in oceanic lithosphere is proportional to lithospheric age. Updoming of the lithosphere caused by a temperature perturbation in the upper mantle can be an effective mechanism for rifting only when updoming is associated with a reduction in the thickness and the strength of the mechanically strong part of the lithosphere. These findings explain why relatively lew uplifts generate new rifts.