Geodynamics of Geological Processes

SUMMARY. Our research programme concerns geodynamics/tectonics of the lithosphere and its interactions with the mantle and surface processes. Contrary to early plate tectonic concepts, lithospheric plates are not rigid. Although deformation is focussed on plate boundaries, continental interiors and their margins also experience widespread deformation. Our research is motivated by the need to understand lithospheric deformation quantitatively, and what forces drive this deformation. We develop and use geodynamical computer modeling experiments as analogues to natural systems and compare their results with observations. In earth sciences these models are inevitably simplifications of nature. Nevertheless, they provide a quantitative framework for the prediction, analysis, and testing of proposed natural processes. The novelty of this approach is that dynamical models can be used to gain insight into the behaviour of complex systems and that these insights are particularly useful when they are unexpected or counterintuitive. Numerical model experiments are designed to be simple but consistent with the first-order thermo-mechanical properties of the lithosphere. Our proposed programme is significant because we can now study and model fully 3D problems. This innovation results from the collaborative development of a fully 3D finite element program (DOUAR) specifically designed to solve geodynamical problems, initial results that demonstrate its applicability to natural problems, and implemented and proposed developments of DOUAR (e.g. sub-scale, nested models) that increase its computational efficiency, speed, and resolution. Specific projects focus on complete Wilson cycle development of large-hot orogens (mountain belts and their roots) and strain partitioning in these orogens, continental rifting and lower lithosphere counterflow, and salt and shale tectonics. The last two have direct implications for the petroleum industry. Our objectives are: 1) to determine how these geodynamical processes operate; 2) to quantify their impact on the geological record; 3) to educate and train highly qualified personnel; 4) to develop software, demonstrate its applicability, and to collaborate with industry partners.