A multi-parametric study of the space-time evolution of the seismicity from 2015 to the beginning of 2020 is performed within a well-focused area, located between the Alps and the Prealps, in the central part of the Friuli Venezia Giulia region (Northeastern Italy). The study area is characterized by a complex tectonic pattern resulting from the interference of differently oriented fault systems and involving mechanically heterogeneous rocks. From 2018 to 2019, the area experienced a significant increase and clustering of radiated seismic energy. The estimated damage pattern emphasizes the tectonic complexity. Notably, the most energetic events are located in correspondence with the sharp transitions from zones of low damage to zones of intermediate damage.

The evolution of seismicity is analyzed through the temporal variation of the Shannon entropy, b-value, fractal dimension, nearest neighbour distance, and changing orientation of the planes inferred from Principal Component Analysis (PCA). The PCA analysis is applied along a geological cross-section to infer the geometry and the time-evolution of the fracturing. It reveals best-fit planes mainly subvertical. Two distinct temporal phases are recognized, characterized by different orientation of planes and propagation of fracturing. The two phases correspond to the changes in the seismic activity, highlighted by the variations of the entropy, b-value, fractal dimension and nearest neighbour distance. The observed spatio-temporal evolution of seismicity is interpreted within the frame of damage evolution in a heterogeneous medium subjected to an applied remote stress.

对 2015 年至 2020 年初地震活动时空演变的多参数研究是在位于弗留利威尼斯朱利亚地区（东北部意大利）。研究区的特征是复杂的构造模式，这是由于不同方向的断层系统的干扰并涉及机械非均质岩石。2018年至2019年，该地区经历了辐射地震能量的显着增加和聚集。估计的损坏模式强调了构造的复杂性。值得注意的是，最活跃的事件与从低破坏区到中度破坏区的急剧转变相对应。

通过香农熵、b 值、分形维数、最近邻距离以及从主成分分析 (PCA) 推断出的平面的变化方向的时间变化来分析地震活动的演变。沿着地质横截面应用 PCA 分析来推断压裂的几何形状和时间演变。它揭示了主要是近垂直的最佳拟合平面。识别出两个不同的时间阶段，其特征是平面的不同方向和压裂的传播。这两个阶段对应于地震活动的变化，以熵、b 值的变化突出显示、分形维数和最近邻距离。观察到的地震活动的时空演变是在受到施加远程应力的异质介质中的损伤演变框架内解释的。