Orogen parallel flow in convergent systems

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Mountain belts typically mark zones where tectonic plates convergence. Most of the deformation associated with mountain building (or orogenesis) is taken up along faults that facilitate horizontal shortening and vertical thickening of the crust, which drives mountain building. Most studies that examine mountain systems (orogens) focus on characterizing changes in structure, metamorphism, and geochronology perpendicular to the structural grain of the orogen. This has been broadly successful in elucidating many of the processes that govern how a mountain system develops. Yet, there remain fundamental questions that have not been solved using this traditional approach, such as reconciling discrepancies in the total convergence across a mountain belt and total the shortening recognized in the geological record. Recent studies within the Himalayan system, the result of collision and convergence between the Indian and Asian plates, have reported local areas of orogen-parallel flow, perpendicular to the expected convergence-parallel direction. Quantifying this out-of-plane movement of material may help solve some of the outstanding issues in understanding orogens such as that mentioned above. Researchers in the Himalaya have offered a variety of different interpretations for the driving mechanisms of orogen-parallel flow, none of which explain all observations in a self-consistent model. The localities in which orogen-parallel flow has been recognized in the Himalaya directly overlie topographic highs in the Indian plate that is being thrust under Asia. This relationship leads to the hypothesis that enhanced compression above such highs forces lateral escape of material to adjacent areas through orogen-parallel flow. Similar geological relationships occur in the Proterozoic Ungava orogen of Nunavik and the Cretaceous fossil subduction zone exposed in the U.A.E. The nature of orogen-parallel flow in the Himalaya, Nunavik and U.A.E. will serve as the focus of multiple HQP-led investigations. In order to understand the details of the conditions, symmetry, characteristics and rates of deformation, the projects will be multi-disciplinary and provide HQP hands-on experience with a variety of highly valuable analytical, project management and data assessment techniques that are directly transferrable to any employment sector. The research proposed herein will contribute to my long-term research program goal of understanding the geological processes that govern how mountain belts develop. Critically, this new research will help quantify the 3D nature of flow in convergent systems, which, at present, is under-investigated, yet fundamental to developing representative thermo-mechanical or analogue models of orogenesis. Such models can be used to inform interpretations of subduction systems, and associated seismic hazards, and ore body distribution in complexly deformed regions.