【摘要】 叙述了用月差值消除形变年变，突出唐山７．８级地震叠加在年变背景上异常的方法，指出这与使用周期函数进行拟合、回归分析、维纳滤波等处理后所显现的形变异常是一致的，表明月差值法是识别异常的一种行之有效的简便方法更多还原

【Abstract】 A method of the anomaly superimposed on annual variation background before the Tangshan M7 8 earthquake stressed through the use of the monthly difference eliminating the annual variation of the deformation data is discussed,and it is showed that the result obtained from the method is coincident with the anomalies displaied through the use of the methods of periodic function fitting,regression analysis,Wienner filtering,and the monthly difference method is a effective and simple method identified anomaly.更多还原