Anisotropy and the Structural Geology of the Tectosphere

各向异性和构造圈的构造地质学

• 批准号: 9805206
• 负责人: Jeffrey Park
• 金额: $ 24.81万
• 依托单位: Yale University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-07-15 至 2002-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9805206&HistoricalAwards=false
• 关键词: Anisotropy; Structural; Geology; Tectosphere

9805206ParkThis research deals with the mapping of seismic anisotropy in the continental crust and upper mantle of the Earth. In both the crust and upper mantle, seismic anisotropy can arise from preferred mineral orientations and fine layering of contrasting rock types. In the crust, anisotropy from aligned cracks is also often present, especially in the upper few km. The strength of anisotropy, its distribution with depth, its relation to plate motion, and the relation between mantle and crustal deformation are pivotal for our understanding of the mechanisms of continental formation and Earth history. This work will combine two complementary body-wave techniques: shear-wave splitting, and P-SH conversions in the P-coda. Continents are the longest-lasting surface remnants of the plate-tectonic engine, and also the principal record of this engine's activity prior to the Mesozoic. By characterizing the patterns of seismic anisotropy in the continental regions of the Earth, this research will investigate the record of process dynamics.

9805206公园这项研究涉及大陆地壳和上地幔地震各向异性的绘制。在地壳和上地幔中，地震各向异性可能是由对比岩石类型的优选矿物取向和精细分层引起的。在地壳中，定向裂缝的各向异性也经常存在，特别是在上部几公里处。各向异性的强度、各向异性随深度的分布、各向异性与板块运动的关系以及地幔与地壳形变的关系，对于我们理解大陆形成机制和地球历史是至关重要的。这项工作将结合两种互补的体波技术：横波分裂和P尾波中的P-SH转换。大陆是板块构造引擎持续时间最长的地表遗迹，也是该引擎在中生代之前活动的主要记录。通过表征地球大陆地区的地震各向异性模式，这项研究将调查过程动力学的记录。