3D Numerical Modeling of Subduction Zone Anisotropy

俯冲带各向异性的 3D 数值模拟

• 批准号: 9814242
• 负责人: Peter Malin
• 金额: $ 6.68万
• 依托单位: Duke University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-01-01 至 1999-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9814242&HistoricalAwards=false
• 关键词: 3D; Numerical; Modeling; Subduction; Zone

9814242 Malin Shear-wave splitting observations in the vicinity of subduction zones of the Pacific indicate that average olivine a-axis orientations beneath back-arcs are variable within and between subduction zones, and those beneath slabs in the seaward-side mantle are predominantly parallel to the trenches. The PI proposes to use a 3-D numerical model to study the effects of simultaneous down-dip and rollback motion of a non-planar plate, and the motion of an overriding plate on upper mantle flow and anisotropy in the vicinity of a subducting slab. The influence of simultaneous slab motion, plate geometry and overriding plate kinematics on mantle flow and anisotropy needs to be examined in more detail than has presently been done. The 3-D numerical model will produce results that can be compared to current shear-wave splitting observations.

9814242在太平洋俯冲带附近的马林剪切波分裂观测表明，平均橄榄石的a轴方向下的弧后是可变的俯冲带内和之间，和那些在板块下的向海侧地幔主要是平行于海沟。 PI建议使用3-D数值模型来研究非平面板块的同时下倾和回滚运动的影响，以及俯冲板片附近的上地幔流动和各向异性的覆盖板块的运动。 同时板片运动，板块的几何形状和覆盖板块运动学对地幔流和各向异性的影响，需要进行更详细的研究比目前所做的。 三维数值模型将产生的结果可以与目前的剪切波分裂观测结果进行比较。