Development of Anisotropy in Deformed Rocks

变形岩石各向异性的发展

• 批准号: 9417580
• 负责人: Hans-Rudolf Wenk
• 金额: $ 15万
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1995
• 资助国家: 美国
• 起止时间: 1995-08-01 至 2000-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9417580&HistoricalAwards=false
• 关键词: Development; Anisotropy; Deformed; Rocks

Wenk 9417580 The proposal is to investigate ductile deformation of polymineralic rocks and accompanying development of preferred orientation and anisotropy. Finite element methods will be used to model deformation of crystal aggregates at the submicroscopic intragrain scale and compare results with analytical upper and lower bounds solutions. Based on results constitutive equations for deformation of plastically anisotropy and heterogeneous polymineralic rocks can be proposed. FEM methods will also be used to model large heterogeneous systems such as convection of the Earth's mantle, with more realistic geometry and material constraints than in a preliminary pilot study. Instead of using a single number for viscosity to describe the material behavior as is done in classical isotropic convection studies, each element will contain an assembly of 500 grains and deform according to principles of strain compatibility and stress equilibrium. These models of anisotropy convection based on polycrystal plasticity concepts will be useful for geodynamics and seismology to understand development and interpretation of anisotropy of elastic waves. ****

Wenk 9417580 建议研究多矿物岩石的韧性变形及其伴随的择优取向和各向异性的发展。 有限元方法将被用来模拟变形的晶体聚集体在亚微观intragrain规模和分析的上限和下限的解决方案的结果进行比较。 根据研究结果，可以提出塑性各向异性和非均质多矿物岩石的变形本构方程。 有限元方法还将用于模拟大型非均质系统，如地幔对流，其几何形状和材料限制比初步试点研究更为现实。 与经典各向同性对流研究中使用单个粘性数值来描述材料行为不同，每个单元将包含500个颗粒的组合，并根据应变相容性和应力平衡原理变形。 这些基于多晶塑性概念的各向异性对流模型将有助于地球动力学和地震学理解弹性波各向异性的发展和解释。 ****