Center for Lithospheric Research, Czech Geological Survey
Building Pangea: Mechanisms of interior and peripheral continental growth
We show an integrated and multidisciplinary approach of continental research from field observations – mapping (geological and geophysical), sampling – laboratory determination of P-T and geochronological and mineral fabric data, geochemistry and analysis of geophysical signal (potential data – gravity and airborne magnetic) and paleomagnetism. This approach results in a large synthesis at the plate scale and allows to assess the mechanical behaviour and rheological properties of the lithosphere during collisional and accretionary processes.
In the interior of the Pangean system (future supercontinent) a new model of lower crustal flow is proposed allowing the redistribution of the lower plate underneath the upper plate at gigantic scales. We call this mechanism relamination and show how this material is coming to the asthenosphere and then relaminates beneath the Moho of the upper plate. We show how this material penetrates the upper plates in the form of translithospheric diapirs.
At the external boundary of the (Pangea) supercontinent, we show how the oceanic accreted systems are transformed into a mature continental lithosphere thereby becoming a stable continent at the contact of hot young/old cold oceans and continental margins.