
To say that last night’s 8.9 earthquake in Japan was horrifying is an understatement. As news stations around the world show photos and video of the damage, the science and specifics of the quake can get lost in the mayhem.
This is Japan’s largest earthquake on record, and the fifth largest in the world since modern recordkeeping began. It is eerily similar to the 9.0 earthquake that struck the Pacific Northwest January 26, 1700, which created a 33 foot high tsunami that reached Japan: http://www.historylink.org/index.cfm?DisplayPage=output.cfm&file_id=5098.
Foreshocks had been occurring for a couple of days before the 8.9 hit, including a 7.2 on the Richter scale. As a flashback to middle school science class, remember that for every number you go up on the Richter scale, ten times the amount of energy is released.
There have been scores upon scores of aftershocks, with a disturbing number of those in the 5.0 to 7.0 range. While they’ve generally been 20 to 40 miles deep, one was as shallow as nine miles. While I don’t have a scientific basis for this, I can’t shake the creepy feeling that another large one could hit.
According to the U.S. Geological Service’s website, those size aftershocks have been occurring as often as every five minutes. They are definitely large enough to be felt, and some of them seem to be lasting longer than what people are used to feeling in these situations.
Japan is part of the Pacific Rim “Ring of Fire” like us, and their east coast runs along a subduction zone, where one plate of the earth’s top crust is moving under another– like us. Here’s what their coast looks like, from http://geology.com/plate-tectonics.shtml:
You can see where one plate is grinding under another, meaning it’s possible that the aftershocks can go on for weeks.
Here’s an illustration of our subduction zone in Washington from
http://earthquake.usgs.gov/learn/glossary/?term=subduction%20zone :
For near real time information on the sizable quakes with links to maps and other useful information, go to the USGS’ site at http://earthquake.usgs.gov/earthquakes/recenteqsww/Quakes/quakes_big.php. Note that the site uses Zulu time; subtract eight hours for Pacific Standard Time.
There is also great information on possible tsunamis at the Pacific Tsunami Warning Center’s website, ttp://ptwc.weather.gov/ . A tsunami occurred in this case when the buckling of the ocean floor dropped the water down and then pushed it up.
Note to people gathering on the coast to watch tsunami waves come in: even when the waves generated by such an event aren’t that high, the rip currents can sweep you away.
You can monitor our local quakes at http://www.ess.washington.edu/recenteqs/latest.htm.
In times like these it can be best to keep your mind on how to help people and the science of the event more than the anxiety-inducing news coverage. And the people of Japan can use our prayers, so there’s already a way that everyone can help, right where they’re at.
*************************************************************************************
Nation will rise against nation, and kingdom against kingdom. There will be famines and earthquakes in various places. All these are the beginning of birth pains. -Matthew 24:7
*************************************************************************************
©2011 H. Hiatt/wildninja.wordpress.com. All articles/posts on this blog are copyrighted original material that may not be reproduced in part or whole in any electronic or printed medium without prior permission from H. Hiatt/wildninja.wordpress.com.