@article{Supino_Scognamiglio_Chiaraluce_Doglioni_Herrero_2024, title={Source characterization of the 20th May 2024 MD 4.4 Campi Flegrei caldera earthquake through a joint source-propagation probabilistic inversion}, volume={3}, url={https://seismica.library.mcgill.ca/article/view/1394}, DOI={10.26443/seismica.v3i2.1394}, abstractNote={<p>On May 20<sup>th</sup>, 2024, an earthquake of magnitude <em>M<sub>D</sub></em> 4.4 nucleated at shallow depth (2.6 km) in the Campi Flegrei caldera (Southern Italy), a densely populated area where an increase in seismic activity has been observed since 2019 attributable to an on-going unrest episode. While the magnitude was moderate, the event produced a strong ground shaking with an observed maximum peak ground acceleration of 3.58 m s<sup>-2</sup>, and several buildings were damaged. Here, we characterize the earthquake source using a probabilistic joint source-propagation spectral inversion in the Fourier space. We estimate a moment magnitude <em>M<sub>w</sub></em> = 3.70 ± 0.13 and a corner frequency <em>f<sub>c</sub></em> = 1.11 ± 0.19 Hz. Assuming a circular rupture model, we estimate a source radius <em>r</em> = 400 ± 70 m and a stress drop <em>Δσ</em> = 3.2 ± 2.2 MPa. The estimated stress drop suggests that future earthquakes in the hypocentral region, considering a possible rupture length of 3 km suggested by previous studies, can have magnitude increased by 1.2 ± 0.3 units with respect to May 20<sup>th </sup>event. A systematic source characterization of the recent seismicity in the caldera would hep in estimating the expected ground motions from future large-magnitude events. </p>}, number={2}, journal={Seismica}, author={Supino, Mariano and Scognamiglio, Laura and Chiaraluce, Lauro and Doglioni, Carlo and Herrero, Andrè}, year={2024}, month={Aug.} }