The possibilities of statistical estimation of quantiles of predicted maximum peak ground acceleration are discussed. The estimation is based on the theory of extreme values. The quantiles of maximum peak ground acceleration are calculated for a spatial grid covering the territory of high seismicity regions of Japan, Kuril Islands, and Kamchatka. A new phenomenon is observed: spatial spots of increased ground acceleration showing essential inhomogeneity not only across the deep ocean trench, but as well along its extension. Some spots exist during all observation time (130 years), whereas some other can disappear or appear during this time interval. The position of majority of spots is correlated with the concentration of underwater sea mounts at the adjacent part of the oceanic plate. The subduction of these sea mounts could induce an increased seismicity. A correlation of spots with sites of increased ( M b − M w ) values is observed also, which can be caused by an increased friction between the plates. Stable spots of higher acceleration are observed for different earthquake catalogs and various time periods. Our results make advisable using the extreme values theory technique for statistical estimation of seismic hazard, in particular, for characterization of seismic activity spots.

中文翻译：

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西北太平洋地震地面加速度统计及时空结构

讨论了对预测的最大峰值地面加速度的分位数进行统计估计的可能性。该估计基于极值理论。最大峰值地面加速度的分位数是针对覆盖日本、千岛群岛和堪察加半岛高地震活动地区领土的空间网格计算的。观察到一种新现象：地面加速度增加的空间点不仅在深海海沟中，而且在其延伸范围内都显示出基本的不均匀性。一些斑点在所有观测时间（130 年）内都存在，而另一些斑点可能在这段时间间隔内消失或出现。大多数斑点的位置与大洋板块相邻部分的水下海山的浓度有关。这些海山的俯冲可能导致地震活动增加。还观察到斑点与 (M b - M w ) 值增加的位置的相关性，这可能是由板之间的摩擦增加引起的。对于不同的地震目录和不同的时间段，观察到更高加速度的稳定点。我们的结果建议使用极值理论技术进行地震危险的统计估计，特别是用于表征地震活动点。