Poulet Thomas, Behnoudfar Pouria
Commonwealth Scientific and Industrial Research Organisation (CSIRO) Mineral Resources, Kensington, Perth, WA, 6151, Australia.
Sci Rep. 2023 Dec 28;13(1):23095. doi: 10.1038/s41598-023-50759-0.
Stress orientation information is invaluable to evaluate active tectonic forces within the Earth's crust. The global dataset provided by the World Stress Map offers a rich resource of stress indicators, facilitating the calibration of mechanical models to extract complete stress and displacement fields. However, traditional inversion processes are hampered by the manual tuning of geomechanical properties and boundary conditions to reconcile simulations with observations. In this study, we introduce ML-SEISMIC (machine learning for stress estimation integrating satellite image and computational modelling), a physics-informed deep neural network approach to autonomously align stress orientation data with an elastic model. It nearly completely bypasses the need for explicit boundary condition inputs and yields comprehensive distributions of material properties, displacements, and stress tensors. Application of this methodology to Australia, coupled with precise global navigation satellite systems observations, unveils a robust and scale-independent interpolation framework. Additionally, it pinpoints regions where stress orientation reinterpretation is warranted. Our results present a streamlined yet powerful process, offering a substantial leap forward in geodynamic investigations. This approach promises to unify velocity and stress orientation observations with physical models, ushering in a new era of insights into Earth's dynamic processes.
应力方向信息对于评估地壳内的活动构造力非常重要。世界应力图提供的全球数据集提供了丰富的应力指标资源,有助于校准力学模型以提取完整的应力和位移场。然而,传统的反演过程受到地质力学性质和边界条件的人工调整的阻碍,以便使模拟与观测结果相协调。在本研究中,我们引入了ML-SEISMIC(结合卫星图像和计算建模的应力估计机器学习方法),这是一种基于物理的深度神经网络方法,用于自动将应力方向数据与弹性模型对齐。它几乎完全绕过了对显式边界条件输入的需求,并产生了材料属性、位移和应力张量的综合分布。将该方法应用于澳大利亚,并结合精确的全球导航卫星系统观测,揭示了一个强大且与尺度无关的插值框架。此外,它还指出了需要重新解释应力方向的区域。我们的结果展示了一个简化而强大的过程,在地球动力学研究方面取得了重大进展。这种方法有望将速度和应力方向观测与物理模型统一起来,开创一个洞察地球动态过程的新时代。