Geodynamics of Geological Processes

总结。我们的研究项目涉及岩石圈的地球动力学/构造及其与地幔和地表过程的相互作用。与早期板块构造概念相反，岩石圈板块不是刚性的。虽然变形集中在板块边界，但大陆内部及其边缘也经历了广泛的变形。我们研究的动机是需要定量地了解岩石圈的变形，以及是什么力量驱动了这种变形。我们开发和使用地球动力学计算机模拟实验作为自然系统的类比，并将其结果与观测结果进行比较。在地球科学中，这些模型不可避免地是对自然界的简化。然而，它们为预测、分析和测试提出的自然过程提供了一个定量框架。这种方法的新颖之处在于，动态模型可以用来洞察复杂系统的行为，当它们出乎意料或违反直觉时，这些洞察特别有用。数值模型实验设计简单，但符合岩石圈的一级热力学性质。我们提出的计划意义重大，因为我们现在可以研究和模拟完全3D问题。这一创新源于专门用于解决地球动力学问题的全3D有限元程序（DOUAR）的合作开发，初步结果表明其适用于自然问题，以及DOUAR的实施和建议发展（例如亚尺度，嵌套模型），从而提高了其计算效率，速度和分辨率。具体项目侧重于大热造山带（山带及其根）的完整威尔逊旋回发育和这些造山带的应力分配、大陆裂陷和下岩石圈逆流以及盐和页岩构造。后两者对石油工业有着直接的影响。我们的目标是：1)确定这些地球动力学过程是如何运作的；2)量化它们对地质记录的影响；（三）教育和培养高素质人才；4)开发软件，证明其适用性，并与行业伙伴合作。

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.