Seismic Anisotropy in the Lower Mantle: Systematics, Modeling and Interpretation

9814554 Garnero这项研究是对地球上核幔边界（CMB）区域（称为D”）上方区域的调查的继续。 其中包括：确定/绘制太平洋海底小到中等规模的强烈横向不均匀变化图;绘制可变D”不连续结构和地震波速度各向异性图;在CMB发现可变薄（5-40 km）超低速（10%慢）层;探测最外层岩心的地震结构。 本计画将详细探讨D”各向异性的系统学。 除了记录D”穿越横波的走时分裂模式外，波形不规则性的地理系统学也有令人信服的证据。 这些特征将被绘制成地图，并与阿拉斯加、北方太平洋、加勒比海、欧亚大陆和印度/印度洋下采样良好的D”区域的下地幔异质性相关。 目标之一是更好地理解俯冲板块可能与D”各向异性和结构的关系。

9814554GarneroThis research is a continuation of investigations of the region of the earth just above the core-mantle boundary (CMB) region known as D". These include: identifying/mapping out small to medium-scale strong lateral variations in heterogeneity beneath the Pacific; mapping variable D" discontinuity structure and seismic wave speed anisotropy; discovering a variable thin (5-40 km) ultra-low velocity (10% slow) layer at the CMB; and probing seismic structure of the outermost core. This project will address in increasing detail the systematics of D" anisotropy. In addition to documenting patterns in travel time splits of D" traversing shear waves, there is compelling evidence for geographical systematics in waveform irregularities. These features will be mapped and related to lower mantle heterogeneity for the well-sampled D" regions beneath Alaska, the northern Pacific, the Caribbean, Eurasia, and India/Indian Ocean. One of the goals is to better understand the relationship that subducting slabs may have with D" anisotropy and structure.