Forward and Inverse Models of Coupled Plate Tectonics and Mantle Convection using Data Assimilation

使用数据同化的耦合板块构造和地幔对流的正演和反演模型

• 批准号: 0810303
• 负责人: Michael Gurnis
• 金额: $ 37.5万
• 依托单位: California Institute of Technology
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-07-01 至 2012-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0810303&HistoricalAwards=false
• 关键词: Forward; Inverse; Models; Coupled; Plate

In this project, we will study the forces that drive plate tectonics and continental drift. Plate tectonics is the surface expression of thermal convection, representing the overall process by which the earth acts as a giant heat engine. A basic understanding of mantle convection contributes to understanding processes that control natural hazards (great earthquakes) and the occurrence of oil (within deep, offshore sedimentary basins). In this project, we will develop sophisticated computer models that resolve the forces driving and resisting plate tectonic motions. The models will assimilate some data sets (meaning that they will be input as constraints) and then they will be tested by independent data. On a global scale, the models will be the most sophisticated (in terms of both resolution and physics) attempted by any group internationally. To achieve the resolution required, we may use the largest computers that NSF is now installing. An important impact of the project will be the training of two Ph.D. students in geophysics. They will gain enormous experience with sophisticated numerical methods, supercomputing technologies, and the linkage of data with numerical models, especially the linkage between earth dynamics and sedimentary basin evolution. These skill sets are important for scientists needed by international oil companies in their search for oil in deep sedimentary basins.In our research, we link plate motions, mantle structure, and vertical motions with forward and inverse numerical models. The research will require a greater level of data integration than can now be achieved with a combination of software we have developed. This research involves three closely applied topics. First, it involves the prediction of global plate motions as a function of time, using highly resolved finite element models in which the variable viscosity of the plate margins, slabs, and mantle wedges are accounted for. Second, it involves the prediction of global (eustatic) and relative sea level changes using a new paleogeography-mantle convection system that we have developed. Third, it involves further development and application of inverse and adjoint models using seismic tomography, dynamic topography constraints, and plate motions.

在这个项目中，我们将研究驱动板块构造和大陆漂移的力量。板构造是热对流的表面表达，代表地球充当巨型热发动机的整体过程。对地幔对流的基本理解有助于理解控制自然危害（巨大地震）和石油发生（在深，离岸沉积盆地）的过程。在这个项目中，我们将开发复杂的计算机模型，以解决驱动力和抵抗板块构造运动的力量。这些模型将吸收某些数据集（这意味着它们将作为约束输入），然后将它们通过独立数据进行测试。在全球范围内，这些模型将是任何国际群体尝试的最复杂的（就解决方案和物理学而言）。为了实现所需的分辨率，我们可以使用NSF现在正在安装的最大计算机。该项目的重要影响是培训两位博士学位。地球物理学的学生。他们将通过复杂的数值方法，超级计算技术以及数据与数值模型的链接，尤其是地球动力学与沉积盆地演化之间的联系，从而获得巨大的经验。这些技能集对国际石油公司在深层沉积盆地寻找石油所需的科学家至关重要。在我们的研究中，我们将板块运动，地幔结构和垂直运动与前进数值模型联系起来。与我们开发的软件组合相比，这项研究将需要比现在可以实现的数据集成水平更高。这项研究涉及三个密切应用主题。首先，它使用高度分辨的有限元模型涉及全局板运动作为时间的函数，其中板缘，板和地幔楔的可变粘度被解释了。 其次，它涉及我们开发的新的古地理对流系统对全球（Eustatic）和相对海平面变化的预测。第三，它涉及使用地震断层扫描，动态形态约束和板块运动的进一步开发和应用逆模型。