Computational Analysis of Geological Formations on Multiple-Length and Time Scales

该项目的主要目的是对地质材料和地层进行多尺度表征。地质构造常常在几个长度尺度上表现出构造。例如，除了材料微观结构外，在现场尺度模拟中采用的有限网格分辨率下，可能存在渗透节理集。因此，将开发一种多级均匀化程序，以促进从高清晰度图像尺度(< 2mm) ->尺度的材料非均质性（例如微裂缝，小型天然裂缝）->地质尺度元素尺寸（5-10m）的升级。该问题的多尺度性质进一步复杂化，因为需要纳入问题的多个时间尺度，从地震可测量的动态断层传播的应力重新分布到发生在数百万年尺度上的化学主导的微观结构演化。这将需要使用适当的时间尺度，并在多个时间尺度上制定新的与时间有关的材料模型。拟议的博士研究工作将结合斯旺西大学（Peric教授）的学术知识和工业合作者（Crook博士，TCGA）的工业研究专业知识，旨在开发耦合地质力学/流动建模框架，用于模拟地质时间框架内的油田尺度和盆地尺度演化。在这个项目中开发的多尺度和多物理场建模技术将嵌入到一个新的强非线性问题的计算框架中，该框架将针对地质过程的大规模应用进行模拟。

The main aim of this project is to undertake a multiscale characterisation of geological materials and formations. Geological formations often exhibit structure on several length-scales. For instance, in addition to the material microstructure, pervasive joint sets may exist below/at the resolution of the finite mesh employed in field-scale simulations. Consequently, a multi-level homogenization procedure will be developed to facilitate upscaling from: high definition image scale (< 2mm) -> scale of material heterogeneities (e.g. micro-cracks, small-scale natural fractures) -> geological-scale element size (5-10m). The multiscale nature of the problem is further compounded by the requirement to incorporate the multiple time-scales of the problem, which range from stress redistribution from seismically measurable dynamic fault propagation to the chemically dominated microstructure evolution that occurs on a scale of several million years. This will necessitate use of appropriate time-scales and the formulation of novel time-dependent material models on multiple time-scales.The proposed PhD research work will combine academic knowledge within Swansea University (Prof Peric) and industrial research expertise of industrial collaborator (Dr Crook, TCGA), with an aim to develop coupled geomechanical/flow modelling framework for simulation of field-scale and basin-scale evolution over geological time frames. Multiscale and multiphysics modelling techniques developed within this project will be embedded in a novel computational framework for strongly nonlinear problems, which will target simulations of very large-scale applications of geological processes.