Global Attenuation Model of the Whole Mantle Using Waveform Tomography

9706380 Romanowicz这项研究是为了解决地幔衰减的横向变化，这可以帮助我们更好地了解总体地幔环流中的上升流特征。在最近的工作中，基于谱域中的基模面波数据，建立了上地幔剪切衰减的三维模型。该模型的横向分辨率相当于六次球谐展开的横向分辨率。应用一种新的面波和体波地震记录波形反演方法，建立了全地幔12度SH速度模型。这项工作包括将波形形式扩展到包括非大圆路径传播和时间域中滞弹性结构的反演。这将允许利用体波信息对地幔进行更深层次的探测，并最终提高Q模型的横向分辨率。***

9706380 Romanowicz This research is to resolve lateral variations in attenuation in the earth's mantle, which can help improve our understanding of the character of upwellings in the general mantle circulation. In recent work, a 3D model of shear attenuation in the upper mantle was developed, based on fundamental mode surface wave data in the spectral domain. The lateral resolution in this model is equivalent to that of a degree 6 spherical harmonics expansion. A new formalism developed for waveform inversion of surface wave and body wave seismograms was applied to obtain a degree 12 SH velocity model of the whole mantle. This work involves extending the waveform formalism to include off- great-circle path propagation and inverting for anelastic structure in the time domain. This will allow a deeper probing into the mantle using body wave information and eventually increase the lateral resolution of the Q models. ***