地震预报中最困难的问题之一仍然是观测前兆异常。为了制订震源物理过程的详细模式和估计各种震源情况的差别,需要有多种情况下大量前兆异常的坚实的资料基础。一旦获得这种资料基础,我们就有可能为提高预报的成功率和减轻地震灾害设计最佳的地震预报程序。但这种高质量的前兆异常资料基础的积累过程是缓慢的。首先,我们要宣布的是美国研究者已实现了两次地震的长期预报。虽然这两次地震的发 One of the most difficult problems in earthquake prediction is still the observation precursor anomaly. In order to develop a detailed model of the hypophysic physical processes and to estimate the differences in the various hypotheses, a solid data base with a large number of precursory anomalies is needed in many cases. Once we have this information base, we have the potential to design the best earthquake prediction program for increasing the success rate of forecasts and mitigating earthquakes. However, the accumulation process of this high-quality precursory anomalous data base is slow. First, we want to announce that American researchers have achieved long-term forecasts of two earthquakes. Although these two earthquakes hair