[Island Chris]

http://earthquake.usgs.gov/earthquakes/e...is#general

There was a M7.0 earthquake about 28 hours after a M6.2 quake, near the city of Kumamoto on Kyushu, Japan. Well, it looks like it was in the city, with the 6.2 epicenter beneath a hill or mountain. By the way, that topographic feature with the 1592 m mountain east of the quakes is a volcanic caldera. Some far field aftershocks. M5.5 and 5.3, are located near the edge of the caldera. I think this is Aso volcano (dod not check).

Both quakes are strike-slip and shallow.

CNN says dozens of fatalities. If the city is on a deep sedimentary basin, it might be an interesting comparison to Los Angeles: quakes on Newport-Inglewood or Palos Verdes or Elsinore-Whittier faults.

Chris

[Skywise]

When I first saw the pictures of the damage, it was obviously a shallow quake. Although, USGS still shows the the default depth of 10km. Still, I'm a bit surprised since this is a only a little more powerful than the M6.7 Northridge quake in 1994, and the damage from that seems less than the current Japan quake. I guess the difference could be that this quake's location is far enough away from major cities that buildings haven't been updated enough.

The aftershocks already nicely illuminate the fault, and matches with the finite fault model on the USGS page for the quake.

Brian

[Island Chris]

A M 7.0 shallow strike-slip quake would usually break to the surface.

There is an interesting comment on far field triggering:
http://www.cnn.com/2016/04/18/americas/e...index.html



"Usually we don't think earthquake are connected across the ocean," Caruso said, but there's ongoing research in "remote triggering," the idea that a big quake can cause another quake a long distance away.

The distance between Japan and Ecuador: 15,445 kilometers, or about 9,590 miles.
A M 7.0 shallow strike-slip quake would usually break to the surface.

Brian, send me an email about what is up with you. Interesting quakes, and Earthwaves just is not interesting without some back-and-forth.

Chris

[Skywise]

(04-19-2016, 09:51 AM)Island Chris Wrote: Brian, send me an email about what is up with you.

Chris, I sent you a private message here on Earthwaves.

Brian