Teleseismic Studies of 'Quiet' Earthquakes and Other Events Of Anomalously Long Duration

这项研究遵循了先前NSF开发的进展 补助金，其中制定了新的检测技术， 描述持续时间过长的地震。 一个新的正常模式激发事件的10年目录已经 这使得系统地识别缓慢的 全球范围内的地震。 这导致了 一种新型的地震，它激发自由振荡， 不产生长周期或短周期可观察到的波群， 周期地震图，称为“平静地震”。“这些不寻常的 慢事件可能是快速破裂的附属物，或者是正常的 地震 这项研究将更准确地定义慢 破裂，并调查它们是否过大 破坏性事件，从而提供了一种手段， 预测. 这项研究是国家 减少地震灾害计划。

This research follows advances developed under a prior NSF grant where new techniques were formulated for the detection and characterization of earthquakes with anomalously long duration. A new 10-year catalog of normal-mode excitation events has been made that allows the systematic identification of slow earthquakes on a global scale. This has led to the discovery of a new type of earthquake which excites free oscillations but does not generate wave groups observable on long-period or short- period seismograms, called "quiet earthquakes." These unusually slow events may be precursory to fast ruptures, or normal earthquakes. This research will more precisely define the slow ruptures and investigate whether they are precursory to large damaging events and thus provide a means of short-term earthquake prediction. This research is a component of the National Earthquake Hazard Reduction Program.