For an ω²-source model, moment-based estimates of the stress drop are obtained by combining corner frequency and seismic moment source parameters. Therefore, the moment-based estimates of the stress drop are informative about the amount of energy radiated at high frequencies by dynamic rupture processes. This study aims to systematically estimate such stress drop from the harmonized dataset at the European scale and to characterize the distributions of the stress drop for application in future stochastic simulations. We analyze the seismological records associated with shallow crustal seismic events that occurred in Western Europe between January 1990 and May 2020. We processed 220,000 high-quality records and isolated the contributions of the source, site, and path contributions using the Generalized Inversion Technique. The source parameters, including the corner frequency, moment magnitude, and stress drop, of 6135 seismic events are calculated. The events processed are mainly tectonic events (e.g., earthquakes of the central Italy 2009–2016 sequence), although non-tectonic events associated with the Groningen gas field and mining activities in Western Europe are also included in the analysis. The impact of different attenuation models and reference site choices are evaluated. Most of the obtained source spectra follow the standard ω²-model except for a few events where the data sampling considered does not allow an effective spectral decomposition. The resulting stress drop shows a positive correlation with moment magnitude between 3 and 4, and a self-similarity for magnitudes greater than 4 with a mean stress drop of 13.8 MPa.

对于 ω ²源模型，通过结合角频率和地震矩源参数来获得基于力矩的应力降估计。因此，基于力矩的应力降估计可以提供有关动态破裂过程在高频下辐射的能量的信息。本研究旨在从欧洲范围内的统一数据集中系统地估计这种应力降，并表征应力降的分布，以便在未来的随机模拟中应用。我们分析了 1990 年 1 月至 2020 年 5 月期间西欧发生的浅地壳地震事件相关的地震记录。我们处理了 220,000 条高质量记录，并使用广义反演技术隔离了震源、地点和路径的贡献。计算了6135个地震事件的震源参数，包括角频率、矩震级和应力降。处理的事件主要是构造事件（例如，意大利中部2009-2016年序列的地震），尽管与格罗宁根气田和西欧采矿活动相关的非构造事件也包括在分析中。评估不同衰减模型和参考站点选择的影响。大多数获得的源光谱都遵循标准 ω ²模型，除了少数事件外，其中考虑的数据采样不允许进行有效的光谱分解。由此产生的应力降与 3 到 4 之间的力矩大小呈正相关，并且对于大于 4 的力矩大小具有自相似性，平均应力降为 13.8 MPa。