The aim of this paper is to analyse the seismic activity of the Iberian Peninsula and a wide area of the Republic of Croatia. To do so, two incidence-magnitude seismic parameters have been defined. First, the areas have been divided into several ellipsoidal clusters using Mahalanobis clustering. Four generalised indexes (Mahalanobis Calinski Harabasz, Mahalanobis Davies–Bouldin, Mahalanobis Simplified Silhouette Width Criterion and Mahalanobis Area) have been used to determine the most appropriate number of ellipsoidal clusters, on the basis of which a partition with four and a partition with eleven clusters have been considered. For the wide area of the Republic of Croatia there are fourteen clusters and the five areas that just affect Croatia have been analysed in detail. Then, to analyse the seismic activity of the areas, two incidence-magnitude seismic parameters have been defined and calculated: a) ${\Delta }^{\left(4\right)}$, that represents the minimal number of successive years in which at least one earthquake of magnitude between 4 and 5 has been registered; b) ${\Delta }^{\left(5\right)}$, that shows the number of years in which at least one earthquake of magnitude larger than 5 occurred. The calculation of ${\Delta }^{\left(4\right)}$ for the South-west and the South-east of the Iberian Peninsula has provided two years for both. Regarding ${\Delta }^{\left(5\right)}$, 10 and 12 years have been obtained for the South-west and the South-east of the Iberian Peninsula, respectively. The analysis of Croatia has shown that the Ston–Metković area has the highest seismic activity. The following results have been determined: 5 years for ${\Delta }^{\left(4\right)}$ and 22 for ${\Delta }^{\left(5\right)}$. It should be mentioned that these results cannot be used for predicting earthquakes. However, data about the incidences of earthquake events and their magnitudes can certainly serve as useful information in civil engineering.

本文的目的是分析伊比利亚半岛和克罗地亚共和国广大地区的地震活动。为此，定义了两个入射震级地震参数。首先，使用 Mahalanobis 聚类将这些区域划分为几个椭圆体聚类。已使用四个广义指标（Mahalanobis Calinski Harabasz、Mahalanobis Davies–Bouldin、Mahalanobis Simplified Silhouette Width Criterion 和 Mahalanobis Area）来确定最合适的椭球簇数，在此基础上，一个有四个簇的分区和一个有十一个簇的分区已经考虑了。对于克罗地亚共和国的广大地区，有十四个集群，并详细分析了仅影响克罗地亚的五个地区。然后，为了分析该地区的地震活动，${\Delta }^{\left(4\right)}$，表示至少连续记录一次 4 到 5 级地震的最少年份；b)${\Delta }^{\left(5\right)}$，表示至少发生一次 5 级以上地震的年数。的计算${\Delta }^{\left(4\right)}$伊比利亚半岛的西南部和东南部为两者提供了两年的时间。关于${\Delta }^{\left(5\right)}$, 分别为伊比利亚半岛的西南和东南部获得了 10 年和 12 年。克罗地亚的分析表明，Ston-Metković 地区的地震活动最高。已确定以下结果： 5 年${\Delta }^{\left(4\right)}$ 和 22 为 ${\Delta }^{\left(5\right)}$. 应该指出的是，这些结果不能用于预测地震。然而，关于地震事件发生率及其震级的数据当然可以作为土木工程中的有用信息。