Dragon chart in 青森県東方沖

Dragon chart in 青森県東方沖 (Eastern offshore of Aomori Pref.）just before M7.6 on 2025/12/8.

There are 3 characteristics as below,

• The plots of 1km/10km are on a line a slope of 1.0.⋯There has been no earthquake of 1km since 1998 in this area. There has been 10km earthquake swarm(*) of the M7.6. 
• The plots of 10km/20km/30km/70km are on a line.⋯There has been an 10km/20km/30km earthquake swarms(*) of the M7.6.
• The plots of 30km/40km/50km are on a line.⋯The M7.6 was occurred in 50km, and updated the record of 50km (M7.0 in 1971 was the old record) . There has been M4.0 and M3.9 in 40km. But, the sum isn't satisfied with my difinition for earthquake swarms(*). There has been 30km earthquake swarm(*) of the M7.6.

(*)  Earthquake swarm is defined as earthquakes per depth within 24 hours in this case.

M7.6 on 2025/12/8 changed the record of the maximum magnitude of 50km from M6.0.

The new dragon chart is below,

The 50km plot shifted vertically and is now located on a line between 80km parallel to the line between 40km/50km.