【摘要】 对美国加州地区 1 976～ 1 994年 6级以上强震的加卸载响应比的时空演化过程进行了系统分析 ,指出该地区强震前响应比在震前 3～ 4年开始大范围出现与该地区的区域构造走向一致的高 Y区 ,高 Y区以每年数十公里的速率向震中附近地区收缩 .震中附近地区的响应比异常主要呈“升—降”型特征 ,多数地震在震前 1年内响应比才升高 ,并且上升曲线较陡 .该区内正地震一般形成丛集区 ,主震发生在正地震丛集区内或边缘 .在分析美国加州地区地震与中国大陆地区地震特征异同的基础上 ,讨论了如何应用响应比的时空演变特征 ,对美国加州地区强地震三要素 (地点、时间、强度 )的中期预测进行估计的步骤与方法 .更多还原

【Abstract】 WT5BZ]In this paper, the tempo spatial evolution characteristics of the load/unload response ratio (namely LURR or Y value) before strong earthquakes with magnitude over M =6 during 1976～1994 in California of America are studied in detail. The results show that there appear some high Y regions cohering with the regional tectonic trend in a great area 3~4 years before strong earthquakes and these high Y regions migrate from the periphery to the epicenter region at a speed of tens kilometers per year. The LURR anomalies near the epicenter region characterizes a type of “ascend → descend” and appear and increase steeply until one year or less before most strong earthquakes. Positive earthquakes form usually a concentration area; in and near which the main shock occurs. We have analyzed the different and the same characters of earthquakes between California of American and the Chinese Mainland. Basing on these results, we discuss the approach and method how to predict and estimate the three parameters (place, time and magnitude) of a strong earthquake in California of American by applying the characteristics of the LURR.更多还原