Spatiotemporal Evolution of Ground-Motion Intensity at the Irpinia Near-Fault Observatory, Southern Italy

التفاصيل البيبلوغرافية
العنوان: Spatiotemporal Evolution of Ground-Motion Intensity at the Irpinia Near-Fault Observatory, Southern Italy
المؤلفون: Matteo Picozzi, Fabrice Cotton, Dino Bindi, Antonio Emolo, Guido Maria Adinolfi, Daniele Spallarossa, Aldo Zollo
المساهمون: Picozzi, Matteo, Cotton, Fabrice, Bindi, Dino, Emolo, Antonio, Maria Adinolfi, Guido, Spallarossa, Daniele, Zollo, Aldo
المصدر: Bulletin of the Seismological Society of America
بيانات النشر: Seismological Society of America (SSA), 2021.
سنة النشر: 2021
مصطلحات موضوعية: Geophysics, Geochemistry and Petrology
الوصف: Fault zones are major sources of hazard for many populated regions around the world. Earthquakes still occur unanticipated, and research has started to observe fault properties with increasing spatial and temporal resolution, having the goal of detecting signs of stress accumulation and strength weakening that may anticipate the rupture. The common practice is monitoring source parameters retrieved from measurements; however, model dependence and strong uncertainty propagation hamper their usage for small and microearthquakes. Here, we decipher the ground motion (i.e., ground shaking) variability associated with microseismicity detected by dense seismic networks at a near-fault observatory in Irpinia, Southern Italy, and obtain an unprecedentedly sharp picture of the fault properties evolution both in time and space. We discuss the link between the ground-motion intensity and the source parameters of the considered microseismicity, showing a coherent spatial distribution of the ground-motion intensity with that of corner frequency, stress drop, and radiation efficiency. Our analysis reveals that the ground-motion intensity presents an annual cycle in agreement with independent geodetic displacement observations from two Global Navigation Satellite System stations in the area. The temporal and spatial analyses also reveal a heterogeneous behavior of adjacent fault segments in a high seismic risk Italian area. Concerning the temporal evolution of fault properties, we highlight that the fault segment where the 1980 Ms 6.9 Irpinia earthquake nucleated shows changes in the event-specific signature of ground-motion signals since 2013, suggesting changes in their frictional properties. This evidence, combined with complementary information on the earthquake frequency–magnitude distribution, reveals differences in fault segment response to tectonic loading, suggesting rupture scenarios of future moderate and large earthquakes for seismic hazard assessment.
وصف الملف: application/pdf
تدمد: 1943-3573
0037-1106
DOI: 10.1785/0120210153
URL الوصول: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::66bed45e4ff3b1e368c2c122bcafe67c
https://doi.org/10.1785/0120210153
Rights: OPEN
رقم الانضمام: edsair.doi.dedup.....66bed45e4ff3b1e368c2c122bcafe67c
قاعدة البيانات: OpenAIRE
الوصف
تدمد:19433573
00371106
DOI:10.1785/0120210153