{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T02:43:13Z","timestamp":1760150593449,"version":"build-2065373602"},"reference-count":52,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2023,12,1]],"date-time":"2023-12-01T00:00:00Z","timestamp":1701388800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>Significant seismic activity has been witnessed in the area of Ridgecrest (Southern California) over the past 40 years, with the largest being the Mw 5.8 event on 20 September 1995. In July 2019, a strong earthquake of Mw 7.1, preceded by a Mw 6.4 foreshock, impacted Ridgecrest. The mainshock triggered thousands of aftershocks that were thoroughly documented along the activated faults. In this study, we analyzed the spatiotemporal variations of the frequency\u2013magnitude distribution in the area of Ridgecrest using the fragment\u2013asperity model derived within the framework of non-extensive statistical physics (NESP), which is well-suited for investigating complex dynamic systems with scale-invariant properties, multi-fractality, and long-range interactions. Analysis was performed for the entire duration, as well as within various time windows during 1981\u20132022, in order to estimate the qM parameter and to investigate how these variations are related to the dynamic evolution of seismic activity. In addition, we analyzed the spatiotemporal qM value distributions along the activated fault zone during 1981\u20132019 and during each month after the occurrence of the Mw 7.1 Ridgecrest earthquake. The results indicate a significant increase in the qM parameter when large-magnitude earthquakes occur, suggesting the system\u2019s transition in an out-of-equilibrium phase and its preparation for seismic energy release.<\/jats:p>","DOI":"10.3390\/e25121612","type":"journal-article","created":{"date-parts":[[2023,12,1]],"date-time":"2023-12-01T08:36:59Z","timestamp":1701419819000},"page":"1612","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Spatiotemporal Variations of the Frequency\u2013Magnitude Distribution in the 2019 Mw 7.1 Ridgecrest, California, Earthquake Sequence"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0009-0008-9345-789X","authenticated-orcid":false,"given":"Eirini","family":"Sardeli","sequence":"first","affiliation":[{"name":"Section of Geophysics-Geothermics, Department of Geology and Geoenvironment, National and Kapodistrian University of Athens, 15772 Athens, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0284-3867","authenticated-orcid":false,"given":"Georgios","family":"Michas","sequence":"additional","affiliation":[{"name":"Section of Geophysics-Geothermics, Department of Geology and Geoenvironment, National and Kapodistrian University of Athens, 15772 Athens, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6935-5809","authenticated-orcid":false,"given":"Kyriaki","family":"Pavlou","sequence":"additional","affiliation":[{"name":"Section of Geophysics-Geothermics, Department of Geology and Geoenvironment, National and Kapodistrian University of Athens, 15772 Athens, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Filippos","family":"Vallianatos","sequence":"additional","affiliation":[{"name":"Section of Geophysics-Geothermics, Department of Geology and Geoenvironment, National and Kapodistrian University of Athens, 15772 Athens, Greece"},{"name":"Institute of Physics of Earth\u2019s Interior and Geohazards, UNESCO Chair on Solid Earth Physics and Geohazards Risk Reduction, Hellenic Mediterranean University Research & Innovation Center, 73133 Chania, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,12,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"346","DOI":"10.1126\/science.aaz0109","article-title":"Hierarchical Interlocked Orthogonal Faulting in the 2019 Ridgecrest Earthquake Sequence","volume":"366","author":"Ross","year":"2019","journal-title":"Science"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"e2019GL086888","DOI":"10.1029\/2019GL086888","article-title":"Orthogonal Fault Rupture and Rapid Postseismic Deformation Following 2019 Ridgecrest, California, Earthquake Sequence Revealed from Geodetic Observations","volume":"47","author":"Feng","year":"2020","journal-title":"Geophys. 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