Record from a Sacks-Evertson borehole strainmeter at KUT located near Teshikaga, on Hokkaido. The time axis covers about 13 minutes and is labeled hh:mm in UTC. The amplitude axis is marked in nanostrain, so peak-to-peak amplitude is just more than 1 microstrain, a very large signal.

Former Postdoctoral Fellow and current Visiting Investigator Paul Rydelek, now a Visiting Researcher at the Earthquake Research Institute, Tokyo University, experienced firsthand a massive earthquake in Japan.  The 9.0-magnitude earthquake triggered a powerful tsunami along the northeast coast of Japan, launching waves that threatened coastlines as far east as California.  Paul's research at Tokyo University is on the deployment of internet and on-site analysis for earthquake early warning.

In his own words:

From: Paul A Rydelek
Date: March 11, 2011 3:15:52 AM EST

Subject: WOW

Hello,

WOW … by the time you get this email the news of the big quake off the coast of Japan should be front page news in the USA.

Unbelievable strong shaking.  It just kept building and building and after about 30 seconds I started to get scared and wondered if I should leave the building.  I looked out the window and could see the satellite dishes on the building tops shaking like they were leaves in the wind.

Then about 25 minutes later another strong quake struck (probably triggered by the first) and the shaking started all over again.  They had real-time feed of the tsunami hitting the coast and that was amazing to see the amount of water coming in.   This is going to be a disaster and I can’t  imagine the number of fatalities and costs.

WOW … this is the experience of my lifetime and of many of the Japanese I work with. It’s now been about 3 hours since the quake and I’ve already felt 9 aftershocks (that are probably in the Magnitude 6 range).

I am saddened by the thought of the amount of destruction this great earthquake will cause.

Take care,

Paul Rydelek
Earthquake Research Inst., Tokyo Univ.

Ps.  Make that 10 and 11 aftershocks, since two occurred in writing this email.