Uh I don't think 9.1 is twice 8.9, but definitely a powerful quake none the less.

Originally posted by PinkAndBlack
Uh I don't think 9.1 is twice 8.9, but definitely a powerful quake none the less.

Yes, it is. Each level of magnitude is 10 times more powerful. So for every .2 increase, it is twice as powerful.

Well, technically, it's a logarithmic scale...that's why a 9.0 is 10 times as powerful as an 8.0, and it means that a 9.1 is 1.6 times as powerful as an 8.9. Not quite 2, but close enough.

Now, whether or not it's 2, or 1.6, or 1000 times stronger than an 8.9, I don't think it matters...we can see how much energy was released. The attempts to quantify it are interesting, but the damage is done.

Well I suppose another reason this may be significant is that if it was a 9.1, it raises the likely maximum aftershock magnitude potential to 7.6. (Main shock mag minus 1.5)

We've already seen a 7.1 aftershock, so another bigger one statistically might be possible. But this zone has already deviated from the norm, so I am not predisposing anything. For all we know, we could still get the biggest quake ever recorded yet to come.

And I might point out that if they do get another huge quake, how that could affect a pending nuclear disaster. What was possible containment could turn into total disaster.

It's still quite shaking with very frequent tremors, some above the 6.0

I noticed that quakes in the Gulf of California are showing up, too

5.6 2011/03/12 22:31:27 39.225 142.333 25.8 NEAR THE EAST COAST OF HONSHU, JAPAN 6.3 2011/03/12 22:12:46 37.662 141.959 14.3 NEAR THE EAST COAST OF HONSHU, JAPAN
5.3 2011/03/12 21:58:17 39.055 142.319 25.9 NEAR THE EAST COAST OF HONSHU, JAPAN
5.5 2011/03/12 21:48:09 39.626 142.565 24.9 NEAR THE EAST COAST OF HONSHU, JAPAN
5.0 2011/03/12 21:40:58 37.170 143.354 25.3 OFF THE EAST COAST OF HONSHU, JAPAN
5.0 2011/03/12 21:38:35 37.934 144.251 26.2 OFF THE EAST COAST OF HONSHU, JAPAN
5.2 2011/03/12 20:09:55 36.747 144.050 24.2 OFF THE EAST COAST OF HONSHU, JAPAN
5.0 2011/03/12 20:08:25 35.775 141.893 24.5 NEAR THE EAST COAST OF HONSHU, JAPAN
5.0 2011/03/12 19:45:19 -6.187 154.385 62.0 BOUGAINVILLE REGION, PAPUA NEW GUINEA
5.1 2011/03/12 19:11:59 37.730 142.587 13.7 OFF THE EAST COAST OF HONSHU, JAPAN
5.0 2011/03/12 18:28:39 -56.851 -27.963 235.8 SOUTH SANDWICH ISLANDS REGION
6.0 2011/03/12 17:19:24 36.573 142.645 4.3 OFF THE EAST COAST OF HONSHU, JAPAN
5.1 2011/03/12 17:13:02 25.466 -109.727 10.0 GULF OF CALIFORNIA
5.2 2011/03/12 17:11:09 38.051 144.071 29.1 OFF THE EAST COAST OF HONSHU, JAPAN
5.1 2011/03/12 17:01:22 37.701 143.353 38.5 OFF THE EAST COAST OF HONSHU, JAPAN
5.0 2011/03/12 16:38:45 38.067 144.066 25.1 OFF THE EAST COAST OF HONSHU, JAPAN
5.0 2011/03/12 16:22:15 37.891 144.831 34.1 OFF THE EAST COAST OF HONSHU, JAPAN
5.7 2011/03/12 14:43:09 39.471 142.406 21.5 NEAR THE EAST COAST OF HONSHU, JAPAN
5.6 2011/03/12 14:35:00 35.784 141.660 24.4 NEAR THE EAST COAST OF HONSHU, JAPAN
5.3 2011/03/12 14:11:05 25.396 -109.652 12.1 GULF OF CALIFORNIA
5.8 2011/03/12 14:03:30 38.843 142.592 24.8 NEAR THE EAST COAST OF HONSHU, JAPAN
5.2 2011/03/12 13:57:12 36.439 141.926 24.2 NEAR THE EAST COAST OF HONSHU, JAPAN
5.3 2011/03/12 13:26:56 39.381 142.423 25.1 NEAR THE EAST COAST OF HONSHU, JAPAN
6.4 2011/03/12 13:15:42 37.261 141.175 37.5 NEAR THE EAST COAST OF HONSHU, JAPAN
5.8 2011/03/12 12:53:50 37.754 143.573 19.2 OFF THE EAST COAST OF HONSHU, JAPAN
5.7 2011/03/12 11:46:01 35.761 141.656 17.6 NEAR THE EAST COAST OF HONSHU, JAPAN
6.1 2011/03/12 10:53:31 39.075 142.352 24.9 NEAR THE EAST COAST OF HONSHU, JAPAN

Well, since I can't find this listed anywhere on the PTWC site, I have written to them to get confirmation. So we'll see soon hopefully if they respond.

Ok, I did receive a response, and have changed the thread title and updated the OP with new information.

But I can now confirm this is true, it is just that the first story was a bit inaccurate. USGS has yet to update, but it may soon. They may not. We'll see.