A New Approach to Determining Long-Duration Slip of Large Earthquakes

本研究是利用超大型地震的绕地球表面波叠加，消除沿路径变化的速度结构的影响，隔离震源时程。这种技术在140到550秒的表面波周期内最有效。这些低频估计可以与体波模拟的高频估计相结合，以产生对震源的宽带描述。这项技术将应用于自1977年以来以数字方式记录的特大地震，以及一些有特殊意义的早期事件，包括至今仍难以理解的1989年麦夸里岭地震。特别强调在地震发生前寻找长周期的前兆断层滑动。这项研究是国家减少地震危害计划的一个组成部分。＊＊＊

9526873 Nabelek This research is to use the stacking of globe-circling surface waves from very large earthquakes to eliminate the effects of varying velocity structure along the path and isolate the source time history of the earthquake. This technique is most effective in the surface-wave periods of 140 to 550 seconds. These low- frequency estimates can be combined with high-frequency estimates from body wave modeling to produce a broadband description of the earthquake source. The technique will be applied to very large earthquakes recorded digitially since 1977, and a select number of earlier events of special interest including the 1989 Macquarie Ridge earthquake which has been difficult to understand as yet. Special emphasis will be on the search for long-period precursory fault slip prior to the earthquake onset. This research is a component of the National Earthquake Hazard Reduction Program. ***