9 News: The U.S. Geological Survey said quake was centered about 33 kilometres (20 miles) from Gaziantep, a major city and provincial capital. It was 18 kilometres deep. A strong 6.7 temblor rumbled about 10 minutes later.

In Sanliurfa, at least 10 deaths have been confirmed.

That sounds not good. Big earthquake close to populated areas, fairly shallow. That death-toll is gonna go up considerably.

I still associate 921 with Turkey coz about one month before it (Aug 17, 1999) there was 7.6er there that killed 17 000. I remember thinking when 921 struck ok, what happened in Turkey is happening here!

I don't know how well understood the connections are between un-connected, far-away faults - think i've read they're supposedly not connected - but i still have that association. Large bits of the planet are shunting into each other - still seems plausible that they could impact distant major faults. It's a small world after all.

Hopefully, there's no repeat pattern this time - though i'd be slightly on edge around early to mid March.

9 News: Death toll is now up to 3400. The media is reporting an 'aftershock' of 7.5, though i'd categorize that as a twin earthquake event - or an earthquake swarm considering there was also a 6.7. Those poor people living in that area must be freaking out.

Looking at the photos, it's interesting that some buildings survived. Makes you realize the most important thing in earthquake research is engineering.

Looking at the photos, it's interesting that some buildings survived. Makes you realize the most important thing in earthquake research is engineering.

I remember after 921 there was talk of 'unlucky' 12 story buildings collapsing. It was later learned that that height allowed for a resonance of the seismic wave to be hit (not sure what the proper term is). The height allowed the wave to be amplified or at least it did not interrupt the wave. It all had to do with physics more so than construction quality. Buildings a floor or two different of the same quality stayed standing.

They learned that they could place weights on certain floors to counter this effect.

I saw a video today in which the commentator was standing behind a twelve story building that had just collapsed. (Can't find it now. I think it was BBC.) Same effect?

I remember after 921 there was talk of 'unlucky' 12 story buildings collapsing. It was later learned that that height allowed for a resonance of the seismic wave to be hit (not sure what the proper term is). The height allowed the wave to be amplified or at least it did not interrupt the wave. It all had to do with physics more so than construction quality. Buildings a floor or two different of the same quality stayed standing.

That's interesting - i always thought it was coz a stricter building-code kicked-in after 12 floors.

But it could be right. Have noticed that mountain ranges slow down earthquakes the same way they do typhoons - they absorb the impact. A big earthquake in the Rift Valley for example will be significantly reduced by the coastal range by the time it gets to Dulan.

Could be like catching a wave - too low it rolls over you - too high it absorbs the impact up, but 12-floors is where you catch the wave - the sweet-spot for blowing the stack.

Wave analogy is not quite right - if you're near the epicentre of a big earthquake, they don't roll through as a swaying wave like they do if you're 100k away, they violently jump.

So if there's a wave of energy, it's going straight up the building.

Which would make the weights on the roof a reasonable hypothesis. Pretty simple to do. Bad news for all those cool quasi-legal roof-top apartments in Taiwan though ...

Well, I was looking for that video I saw but can't find it. I did find lots and lots of pages detailing how poor construction leads to collapse, such as this one and this one.

There are lots of videos about various dampers used in construction, but I can't find THE video I remember. It was specifically about 12 story buildings in Taiwan.