This comment concerns the recent large earthquakes that have been happening around the Pacific basin.

Terminology:
Earthquake Clusters (sometimes called Megaquake Clusters) concerns earthquakes bigger than 7.0 magnitude, and apparently happening within a short time period. On a geological scale, 10-20 years is a short time period.

Ring Of Fire: A general line of circumference drawn around the Pacific Basin, which includes a lot of earthquake and volcanic activity on the rim (perimeter). During the 1950's and 1960's scientists made a lot of progress understanding why this was happening with a theory called "Plate Tectonics". Check Wikipedia. There are 14-15 major plates covering the surface of the Earth's crust. One of the large ones is the Pacific Plate.

Now let's step forwards. Over the last decade there have been several major quakes around the Pacific rim - including some of the largest earthquakes ever seen. In addition, there have been large quakes on "nearby" tectonic plates, including in Indonesia and Haiti. This has caused the data of large quakes to clump together into a short time period. It has also caused a controversy to erupt amongst scientists over what it all means.

It is worthwhile to note that the science of seismology is a very young science. This field of science only has detailed seismology data over a century or so. If we had all the data going back for 2,000 years - we'd be in a lot better shape (!). Many scientists take the point of view that earthquakes are local phenomena, and not generally connected (except if they occur nearby one another). These people see no relationship between the cluster of big quakes, and feel it is just a random series of events.

Other scientists take the point of view that there is something going on, and some kind of major shift in the tectonic plates is taking place. Notably, the earth scientists in Russia have this point of view - hence the dire warning sent to their own leaders (if news sources can be believed).

I have been looking at this carefully. I am a structural engineer, although not a seismologist. But the two areas have a lot of overlap - we speak the same language. I find the argument that the Pacific Plate is going through a series of movements and a realignment to be compelling. I do understand that data is scarce as hens teeth. We need more.

But I think the Russians may have jumped the gun a little bit. To me, it would not be surprising to see another large quake in the northwest Pacific, in the region of Japan or the Aleutians. I certainly hope that Japan does not get a "double whammy" out of this. It would be devastating to them. But the major seismic zone which lies SE of Tokyo has not triggered yet, and we can't dismiss other fault lines between Japan and Alaska. If these fault lines do rupture, concern about the West Coast of the USA would magnify.

Pete #2