Strong Earthquake Swarm Strikes Japan's Tokara Islands; Geologist Analysis

Hundreds of magnitude 3, 4, and 5 earthquakes have rapidly struck one after the other in Japan's Tokara Islands. This earthquake swarm began on June 21st, and is still ongoing. Is it related to magma movement, perhaps a magma intrusion, or does it have a different potential origin? Today's video discusses the various possibilities through the opinion and analysis of a geologist.

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Sources/Citations:
[1] Japanese Meteorological Agency
[2] Aoyama, H., M. Takeo, and S. Ide, Evolution mechanisms of an earthquake swarm under the Hida Mountains, central Japan, in 1998, J. Geophys. Res., 107(B8), doi:10.1029/2001JB000540, 2002.
[3] Enomoto, Y., Yamabe, T. & Okumura, N. Causal mechanisms of seismo-EM phenomena during the 1965–1967 Matsushiro earthquake swarm. Sci Rep 7, 44774 (2017). https://doi.org/10.1038/srep44774, CC BY 4.0.
[4] Cappa, F., J. Rutqvist, and K. Yamamoto (2009), Modeling crustal deformation and rupture processes related to upwelling of deep CO2-rich fluids during the 1965–1967 Matsushiro earthquake swarm in Japan, J. Geophys. Res., 114, B10304, doi:10.1029/2009JB006398.
[5] U.S. Geological Survey

0:00 Tokara Islands Earthquakes
1:25 Earthquake Swarms
2:30 Possibility 1
3:09 Possibility 2