Assessment of local Seismic records and Spatiotemporal distribution Study in the Comoros Archipelago between 2017 and 2021

Seismic data for the period 2017-2021 (during which a significant earthquake swarm occurred east of Mayotte Island in 2018) were obtained from the Comoros Karthala Volcano Observatory (KVO), and usable sections were selected. This study uses duration magnitude data selected from the KVO data, a complete assembled catalog of 234 seismic events ranging from (Md) ~ 0.64 to 4.95 for Spatiotemporal analysis over the 5 years. Mapping of yearly spatial distribution and a temporal analysis for 2018 yielded the calculated seismic productivity a-value and the relative distribution of the earthquake b-value “a = 5.768±0.16 ≈ 5.77±0.16”, “b = 0.994±0.13 ≈ 0.1±0.13”. A comprehensive stress regime was created with a generated 3D seismic surface visualization showing that the accumulated seismic stress field derived from the 234 earthquakes and stress calculation “σ_ i (x,y) = 9 815 400” on the highest Md4.95 concentrated in the East of Mayotte Island in 2018. No significant NW-SE mainshock-aftershock extension of the five-year spatial distribution patterns was observed. Furthermore, the range of a-value and b-value supports a regional stress type resulting from seismo-volcanic unrest. The 2017-2021 spatial distribution and the 2018 temporal analysis, along with the cumulative earthquake stress field regime, provide an alternative approach to deciphering volcano-induced seismicity in the Comoros and afford useful insights for the monitoring of volcanic eruptions in the local and regional contexts.