Improved Estimates of the Rotation Rate of the Earth's Inner Core

改进对地球内核自转速率的估计

• 批准号: 9805245
• 负责人: Paul Richards
• 金额: $ 15万
• 依托单位: Columbia University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-07-15 至 2001-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9805245&HistoricalAwards=false
• 关键词: Improved; Estimates; Rotation; Rate; Earth

9805245RichardsThis research involves efforts to improve estimates of the inner core's rate of rotation with respect to the rest of the solid Earth. This project is a continuation of the original research that led to the discovery the inner core super rotation. A search will be made for more seismograms in the critical distance range of 147-155 degrees for paths making an angle less than about 40 degrees between the Earth's north-south spin axis and the ray within the solid inner core. Another search will be made for earthquake doublets in the critical distance regions. Doublets have identical wave patterns and can therefore be used to give high-precision differential travel-time measurements. Modeling will be done to investigate the range of structures that produce observed, low-amplitude PKIKP early arrivals associated with ray paths close to the fast axis in the inner core.

这项研究涉及到改进内核相对于固体地球其他部分的自转速度的估计。该项目是导致发现内核超级旋转的原始研究的继续。将在147-155度的临界距离范围内搜索更多的地震图，寻找地球南北自转轴与固体内核内的射线之间的夹角小于约40度的路径。将在临界距离区域进行另一次地震双星搜索。二重波具有相同的波型，因此可以用来进行高精度的差分走时测量。将进行建模，以调查产生观测到的低幅度PKIKP早期到达的结构范围，这些结构与靠近内核快轴的射线路径相关。