NUMERICAL MODELLING OF TECTONIC AND SURFACE PROCESSES: INSIGHTS INTO CONTINENTAL RIFTING AND THE FORMATION OF PASSIVE MARGINS

The formation and evolution of continental margins and associated rift basins is critical to the understanding of major hydrocarbon provinces. The response of continental margin geomorphology to subsidence and uplift in the short and long-term effects sediments distribution. Over long periods of time, this heterogeneous sediment load has a direct impact on the lithosphere isostasy.

Over the past few years, our ability to understand the evolution of complex lithospheric-scale deformation, such as continental rifting, has been greatly enhanced by improvements in thermo-mechanical numerical modelling techniques and increased computational power. In the mean time, the numerical simulation of surface processes also greatly improved.

Our objective is to implement a 4D tectonic and sedimentary model of a rift basin in order to study feedback mechanisms between lithospheric deformation and surface processes.

We present the preliminary results of the coupling between (i) Underworld, a thermo-mechanical code designed to simulate long-term tectonic evolution of the lithosphere, and (ii) Tellus, a surface processes code designed to simulate the impact of gravity flows (such as rivers, debris flows and turbidity currents) driven by climatic forces (sea level variations and rainfall) to stratigraphy and landscape evolution. A fully parallel implementation has been designed for enabling simulation of the feedback between tectonic and surface processes over high resolution unstructured grid on HPC.

The integration of Underworld and Tellus offers new avenues for studying the mechanical and thermal evolution of continental margins and rift-basins in general, and how this affects hydrocarbon reservoir distribution and preservation.