2:00 PM - 2:15 PM
[MIS10-02] A statistical approach to discover the location and focal mechanism role on possible seismo-ionospheric disturbances
★Invited Papers
Keywords:earthquake, Swarm, focal mechanism, land/sea, geomagnetic field
Nowadays, the Swarm constellation is successfully in orbit from more than 8 years. In this work, an extended Worldwide Statistical Approach is proposed with such a large available dataset, using the same analysis technique of De Santis et al. (2019) and adding some new approaches as the investigation of the frequency of the magnetic and electron density signals along the orbits (about latitudinal profiles as Swarm is in quasi-polar orbit). The large available dataset permitted to confirm the previous results and found the concentration of anomalies for larger events such as M7.5+ (not well observed in De Santis et al., 2019 due to the data availability). Furthermore, we observed that the content of high frequency of the signal of the possible earthquake precursor anomalies becomes more intense as the earthquake is approaching. The huge amount of data permitted also to explore if the land or sea and focal mechanism (normal, reverse, or strike-slip) play a role in the frequency of the possible signal associated with the earthquakes. The focal mechanism has been found to have a weak influence on the frequency of the magnetic signal, while the sea earthquakes are more likely to be preceded by high-frequency magnetic signals than land earthquakes that are more likely preceded by slower magnetic disturbances.
References:
- De Santis, A., et al. (2019). Precursory worldwide signatures of earthquake occurrences on Swarm satellite data. Sci. Rep. https://doi.org/10.1038/s41598- 019-56599.
- Rikitake, T. (1987). Earthquake precursors in Japan: Precursor time and detectability. Tectonophysics, 136, 265–282. https://doi.org/10.1016/0040-1951(87)90029-1.