Studies of Global Seismicity and Earth's Structure

该项目的主要目标是系统地调查全球地震活动和绘制地球内部的三维地图。地震研究的重点是哈佛大学的CMT项目。所有震级大于约5.2级的地震都使用全球分布地震仪的数字数据分析其震源机制。对慢震、火山崩塌、不明地震信号等异常地震现象进行了详细研究。研究结果通过电子邮件和哈佛地震学网站http://www.seismology.harvard.edu发布。地球内部弹性特性的成像是通过开发新数据集和联合反演各种现有数据集来实现的，如绝对和差分旅行时间、表面波色散曲线、全波形和正模光谱。在模型参数化和反演中特别考虑了各向异性（径向、方位角和一般）。模型和衍生数据集可在调查人员的网站上获得

DziewonskiEAR-0207608The principal objectives of this project are the systematic investigation of global seismicity and the three-dimensional mapping of the Earth's interior. The earthquake studies are focused around the Harvard CMT project. All earthquakes with magnitudes greater than approximately 5.2 are analyzed for their source mechanisms using digital data from globally distributed seismographs. Unusual seismic phenomena, such as slow earthquakes, volcanic collapses, and unidentified seismic signals, are investigated in detail. Results are disseminated using electronic mail and the Harvard Seismology web page: http://www.seismology.harvard.edu. The imaging of the elastic properties of the Earth's interior is pursued by development of new data sets and the joint inversion of various existing data sets, such as absolute and differential travel times, surface-wave dispersion curves, full waveforms, and normal-mode spectra. Particular consideration is given to the inclusion of anisotropy (radial, azimuthal, and general) in the model parameterization and inversion. Models and derived data sets are available on the investigators' web site.--