Anisotropic Flow, Depth-Age Relationships and Stratigraphic Disturbances in Polar Ice Sheets: Collaborative Research by University of Washington and University of Colorado

极地冰原的各向异性流动、深度-年龄关系和地层扰动：华盛顿大学和科罗拉多大学的合作研究

• 批准号: 9815160
• 负责人: Raymond Fletcher
• 金额: $ 19.32万
• 依托单位: University of Colorado at Boulder
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-07-01 至 2004-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9815160&HistoricalAwards=false
• 关键词: Anisotropic; Flow; Depth; Age; Relationships

This award supports a collaborative program to bring together glaciology and structural geology to tackle two related cross-disciplinary issues. The project will investigate the geological mechanisms known to operate in anisotropic rocks that may also generate stratigraphic disruptions in polar ice. A series of analytical and semi-analytical models to explore conditions for and onset of folding, kinking, fabric striping, and shear banding in polar ice sheets will be developed using linearization and perturbation methods. A fundamental goal is a new ability to estimate the maximum depths of undisturbed ice for ice cores in various settings. The bulk anisotropic properties of polar ice will also be incorporated in a new finite element dynamic ice flow model. One goal is to extend the models of layer disruption processes to large strains. This model will also be used to improve the predicted depth-age relationships for ice core sites, and to produce improved calculations of the thinning functions needed to convert measured layer thicknesses to past accumulation rates for deep ice that has a strongly anisotropic bulk fabric.

该奖项支持一项合作计划，将冰川学和结构地质学结合在一起，以解决两个相关的跨学科问题。 该项目将调查已知在各向异性岩石中起作用的地质机制，这些岩石也可能在极地冰中产生地层破坏。 一系列的分析和半分析模型，探索条件和发病的折叠，扭结，织物条纹，剪切带在极地冰盖将开发使用线性化和扰动方法。 一个基本目标是一种新的能力，以估计最大深度的冰芯在各种设置的原状冰。 极地冰的体积各向异性特性也将被纳入一个新的有限元动态冰流模型。 一个目标是将层破裂过程的模型扩展到大菌株。 该模型还将用于改进冰芯位置的预测深度-年龄关系，并改进将测得的层厚转换为具有强烈各向异性块状结构的深冰过去累积率所需的减薄函数的计算。