Toward High Resolution Imaging of Earths Deep Interfaces

这是一个为期3年的提案，重点是提供更好的地球短波异质性图像？通过对大量地震反射波的分析，这项研究继续PI？财政司司长的博士后工作，产生了新的高分辨率地图的不连续地形的地幔过渡带。该提案要求3年时间，以严格和彻底地评估大量数据，这些数据量丰富，但难以分析低信噪比数据。在这项研究中，PI建议通过以下方式改进他以前的地幔过渡带叠加反演方法[Lawrence和Shearer，2008]：1）通过非均匀和多重网格反演分析改进成像技术; 2）纳入更多数据和数据类型以提高数据覆盖率。这项研究还将增加技术，以评估地形上的一组更深的接口与D？？对地幔中的反射波的进一步分析将确定在~1100 km深度处的可能的不连续性是否是稳健的，并且用补充数据集独立地确认。如果界面是可靠的，地理分析将确定界面是全球还是区域观测。进一步的分析还将调查其他的可能性，以前未发现的水平，倾斜，和/或半垂直的地幔不连续。新的区域或全球不连续性的验证将对从矿物物理学和地震学到对流建模和地球化学等领域产生重大影响。

This is a 3-year proposal focused on providing better images of short-wavelength heterogeneity in the Earth?fs deep mantle by analyzing large quantities of seismicly reflected waves. This research continues the PI?fs postdoctoral work that generated new high-resolution maps of discontinuity topography for the mantle transition zone. The proposal requests 3 years in order to rigorously and thoroughly evaluate a large data volume with abundant, but difficult to analyze low signal-to-noise data. In this study, the PI proposes to improve upon his previous stacking-inversion method for the mantle transition zone [Lawrence and Shearer, 2008] by 1) improving the imaging technique with non-uniform and multiple grid inversion analyses, and 2) incorporating more data and data types to enhance data coverage. This study will also augment the technique to evaluate topography on a deeper set of interfaces associate with the D?? layer at the core mantle boundary.Further analysis of reflected waves in the mantle will determine if a possible discontinuity at ~1100 km depth is robust, and independently confirmed with complementary data sets. If the interface is robust, geographical analysis will determine if the interface is a global or regional observation. Further analysis will also investigate the possibility of other, previously undiscovered horizontal, tilted, and/or semi-vertical discontinuities in the mantle. The verification of a new regional or global discontinuity would have major impacts on fields ranging from mineral physics and seismology to convection modeling and geochemistry.