Induced Earthquake Source Parameters, Attenuation, and Site Effects From Waveform Envelopes in the Fennoscandian Shield

We analyze envelopes of 233 and 22 ML0.0 to ML1.8 earthquakes induced by two geothermal stimulations in the Helsinki, Finland, metropolitan area. separate source spectra site terms determine intrinsic attenuation scattering strength shear waves 3 Hz 200 frequency range using radiative transfer based synthetic envelopes. Displacement yield scaling relations with a general deviation from self-similarity, stronger albeit more controversial signal weaker 2020 stimulation. The also tend have smaller local magnitude compared 2018 same moment magnitude. discuss these connections context fluid effects on rupture speed or medium properties. Site demonstrate that spectral amplification relative reference borehole sites is not neutral at other sensors; largest variations are observed surface stations frequencies larger than 30 Hz. Intrinsic exceptionally low values down 2.4 × 10−5 20 Hz, which allows observation diffuse reflection ∼50 km deep Moho. Scattering globally data between 10−3 10−4. application employed Qopen analysis program retrospective monitoring mode demonstrates its versatility as seismicity processing tool. diverse results implications for relations, hazard assessment ground motion modeling, imaging ballistic scattered wavefields crystalline Fennoscandian Shield environment.