Seasonal modulation of oceanic seismicity in the azores

The analysis of an 11-year (2008–2018) seismic catalogue the Azores suggests existence secondary cyclic influences on seismicity rate oceanic region, with more earthquakes observed during summer months, from May to August, than in winter. Statistical testing based Monte-Carlo simulations and a Jack-Knife methodology indicate that seasonal modulation affects magnitudes M3.3–4.5, well above magnitude completeness. Here, we investigate variations earthquake considering both whole domain four separate sub-regions, corresponding regional clusters identified by previous authors. shows is particularly near Triple Junction region between Faial Island Mid-Atlantic Ridge. To identify possible mechanisms driving modulation, apply Singular Spectral Analysis time-series plausible external triggers, order common periodicities. We find significant correlations rate, sea level anomaly GRACE satellite anomalies ocean bottom pressure, suggesting water load may modulate seismicity.