Sunday, February 15, 2009

Famous Earthquakes - Kobe 1995


With this mid-size earthquake (M6.7), we learned the true power of the urban earthquake, and something more. After the Armenia earthquake, and then this one, I became convinced there was a bit more to Magnitude, when it came to damage.

The fault that whacked Kobe was way off the beaten path. For years, Japan was only expecting earthquakes from these monstrous faults. Who would expect an interior fault? But this was a thrust fault and it did something very bizarre.

Digression: I'm getting all this from the EQE report! I finally found them all right here!

Now, I can only find the peak accelerations, which were around 0.6 g, but somewhere they must have the PGV's. Looking at the damage, and the videos, I think the PGV hit 1-2 m/s, which is huge! All this from an M6.7

But this was no ordinary earthquake, this was a 'super-pulse', where a high velocity pulse runs up the fault, and smashes the surface! Of course, the soft ground didn't help much.

Since all the water mains were destroyed, there were huge fires.


As always in an EQE report, they looked at things which should have been damaged, but weren't. You never find that in a 'standard' earthquake report. Well-anchored pumping and industrial facilities were not damaged. Well-designed building out of the main swamp were also not damaged.

7 comments:

Silver Fox said...

Nice post! I like hearing about what things weren't damaged. That should really help redesigning for future quakes.

Anonymous said...

'Ello, 'ello, ....
Wot's all this then?

Harold Asmis said...

Neat.

Anonymous said...

You should pout some more detail like on the Type of Fault and the Damaged Caused and also the Rating and more locations :)

Harold Asmis said...

Nah, all the drivel like that is on wikipedia. I'm more interested in the bizzare.

Harold Asmis said...

This has become one of my biggest ever posts. I don't know why.

Harold Asmis said...

This was most likely a supershear earthquake, now explained on

http://ontario-geofish.blogspot.com/2010/12/physics-of-super-shear-earthquake.html