Array-derived rocking and vertical ground motion scaling relations from seismicity induced by the 2018 Espoo/Helsinki geothermal stimulation ...

• Main Authors: Sadeghi-Bagherabadi, Amir, Hillers, Gregor
• Format: Conference Object
• Language: unknown
• Published: GFZ German Research Centre for Geosciences 2023
• Subjects: Fennoscandian
• Online Access: https://dx.doi.org/10.57757/iugg23-2868; https://gfzpublic.gfz-potsdam.de/pubman/item/item_5019000

<!--!introduction!--> The observation of ground motions excited by induced earthquakes near urban areas is of significant engineering importance. During the 2018 geothermal stimulation in the Otaniemi district of Helsinki, Finland, five seismic arrays consisting of 3 to 25 three-component geophones were deployed with interstation distances of 50 meters to record ground motions of 6-km deep induced events. This dataset provides an opportunity to study the ground motion patterns in the low-attenuation environment of the Fennoscandian Shield. The translational seismograms are used to calculate rotational motion for ~400 events with local magnitudes ranging from -0.5 to 1.8 using the seismogeodetic method. We evaluate the relationship between array-derived ground rocking rate (GRR) and vertical ground acceleration (VGA) associated with direct body waves. The robustness of the GRR estimates in the 2-15 Hz frequency range are assessed by comparing the VGA waveforms to the GRRs from the full arrays and to the ... : The 28th IUGG General Assembly (IUGG2023) (Berlin 2023) ...