Data Catalog of Earthquakes around Tohoku of Japan Area has been updated related with M7.6 in 2025/12/8

 As I noticed the skip of the catalog data around Tohoku area of Japan, I have updated one of 青森県東方沖 of Tohoku area. Because, there was M7.6 in the area 3 days ago. So, I have added the special comment to some pages related with the M7.6. 

MD-T chart in 青森県東方沖

MD-T chart in  青森県東方沖 (Eastern offshore of Aomori Pref.）

There has been much blank space in recent years. It means it may be the term for the charge of earthquake energy.

MD chart in 青森県東方沖

MD chart in 青森県東方沖 (Eastern offshore of Aomori Pref.）

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 the depth within 24 hours in this case.

• 

Sum of Magnitude per 1day in 青森県東方沖

Sum of Magnitude per 1day in 青森県東方沖 (Eastern offshore of Aomori Pref.）

note : Horizontal axis isn't linear.

Distribution of Magnitude in 青森県東方沖

Area map of 青森県東方沖 (Eastern offshore of Aomori Pref.）is defined for epicenter's analysis as below,  

The plot of M7.6 (ln 7.6=0.88) is an outlier on the upside.

Distribution of Depth in 青森県東方沖 Eastern offshore of Aomori Pref.

Distribution of Depth in 青森県東方沖 (Eastern offshore of Aomori Pref.）

The center of the cracking is still around 60 km, and the drop in the graph at 10 km suggests that this area has enough capacity of the stocked energy still.