Friday, October 13, 2006

Friday Random Ten

  • Emerald Rose, "Penny in the Well". A warm song about searching for fulfillment.
  • Tim McGraw, "Tiny Dancer". I like this version of the song.
  • Alabama, "Fiddle in the Band". Can you listen to this and not tap your toes?
  • John Denver, "Islands"
  • Jackson Browne, "Running on Empty". A very LA song about growing up.
  • Bruce Cockburn, "All the Diamonds in the World". Gentle and lyrical.
  • Vladimir Vysotsky, "Vyet Eto Nashi Gory (These are Our Mountains)". Russian song that tells of a WWII battle in which Soviet alpine fighters faced German soldiers they themselves had trained. Has anybody tried to translate Vysotsky into English?
  • John Denver, "Rhymes and Reasons". The first John Denver song I ever heard and still one of my favorites. Hopeful and comforting.
  • Trisha Yearwood, "Real Live Woman". An honest, solid song that matches Yearwood's style perfectly.
  • The Highwaymen, "Against the Wind". Good song, but I like Bob Seger's version better.

Now I'm off to the Smokies!

Tuesday, October 10, 2006

What Does It Feel Like to be On Top of a Nuclear Test?

Since North Korea claimed to have tested a nuclear weapon on Monday, geologists and policy wonks have been wondering why the tremor the detonation caused was so small. Was the bomb small, not very good, or fake -- simply a pile of regular explosives? While the authorities study and debate, I am struck by the surrealness of the situation. Human beings have weapons that imitate tectonic plate movements!

I grew up in southern California and have been through several earthquakes, including the magnitude 6.6 Northridge Earthquake in 1994. When I read about the North Korean nuclear-seismological debate, I wondered what it would feel like to be on top of an underground nuclear test.

To find out, I combined a Wikipedia chart of the Richter scale magnitudes of various earthquakes and explosions with a chart giving rough conversions between earthquake magnitudes on the Richter scale and their felt intensities on the Modified Mercali Scale. Here is the result.



































































EventRichter magnitudeTNT EquivalentIntensity
WWII conventional bombs1.5178 kg (392 lb)Detected only by seismographs
late WWII conventional bombs2.01 metric tonDetected only by seismographs
WWII blockbuster bomb

2.55.6 metric tonsDetected only by seismographs
Small atomic bomb4.01 kilotonResembling vibrations caused by heavy traffic.
Nagasaki
atomic bomb
5.032 kilotonSleepers awakened and bells ring.
Little Skull Mtn, NV Quake, 19925.5178 kilotonsTrees sway, some damage from overturning and falling objects.
Double Spring Flat, NV Quake, 19946.01 megaton

General alarm, cracking of walls.
Northridge quake, 19946.55.6 megatonsChimneys fall and there is some damage to buildings.
Tsar Bomba, largest
thermonuclear weapon ever tested
~7.050 megatonsGround badly cracked and many buildings are destroyed. There are some landslides.
Landers, CA Quake, 19927.5178 megatonsGround badly cracked and many buildings are destroyed. There are some landslides.