The Coastal Post - July, 1998

It's Shake Time Again; The Connection Between Nuke Testing And Earthquakes

By Karen Nakamura

Judging from my mail, the gang was mentally together as we helplessly watched the results of the Indian and Pakistan governments' nuclear testing. Approximately 2,500 people died in Afghanistan two days after the first Pakistani test.

Here's the stats:

Indian test:

May 11 10:13:42 UTC ground zero, 5.4


May 12 03:14:00 UTC Guatemala 5.9


May 30 06:22:00 UTC Afghanistan 6.9


May 30 06:54:56 UTC ground zero 4.6


June 1 05:34:00 UTC E. Russia 6.2

For those trying to figure out what we're talking about or just getting into this, the Coastal Post has been watching for any correlation between nuclear testing and earthquakes for a number of years.

During the '95-'96 series of Chinese and French tests, the CP compiled facts from the National Earthquake Center in Golden, Colorado to watch for a connection. This connection was first observed in the '88-'89 nuclear series set off by the US, France, Britain, the then Soviet Union and China.

When the '95-'96 French/Chinese series came up, we set out ahead of time to see if the theory held water. The results were frightening.

Of the eight tests set off by France in the South Pacific and China in its Western desert, all were over 5.0 ground zero except for one and that was a 4.7.

This is important because we're tracking some sort of force wave no one understands and most refuse to believe exists. Does the nuclear impact travel along already established faults? Or does it roll outward in an ever-widening circle like it does when the explosion occurs above ground? Or does it do both? How can a pressure here cause a rumble there?

Using the guidelines of Dr. Gary Whiteford of the University of New Brunswick, a quake may be related to a nuclear test if it comes within 5 days after a test. Occasionally, that time limit is extended up to 10 days.

Eight tests were performed during the French/Chinese series. Within the first 24 hours of four of them, there were five quakes. Eight came between 24-48 hours (two days), six between 48-72 hours (three days), six between 72-96 hours (4 days), six between 96-120 hours (five days) and another six occurring up to eight days afterwards. These are all quakes over 3.5 magnitude.

To understand the magnitude, let's look at the May 15th Chinese test which was a 6.1 ground zero. A day later a 7.7 hit Indonesia and May 17th there was a 6.5 in the same area.

On October 1st, the French set off a test at the Fangataufa Atoll with a 6.0 gz (ground zero). This was a huge denotation, an estimated 110 kilotons of force. October 6th, a 7.0 quake devastated Sumatra. On October 9th, there was a deadly 7.6 Mexico quake.

October 27th, The French again set off a blast, but this time at its usual Mururoa Atoll. The gz was 6.0. On the 29th, there was a 5.7 quake in Azerbaijan, a 6.1 in Indonesia and a 5.5 in Fuji. On the 30th there was a 5.8 in the Solomons, a 5.6 in the Aleutians. On November 1st, there was a 6.3 in Chile, a 5.6 in Japan, and a 5.5 in Kurdistan.

The rebound from tests doesn't always decrease after the first day. In fact, it's been observed that after some particularly large tests, there's an eerie silence with no quakes of any size. Then Boom.

An example is the January 27 French test on Fangataufa Atoll registering 120 kilotons. Hiroshima was 20 kt. It was totally quiet, nothing, until January 30th. Then a 6.2 hit New Zealand. A 6.7 aftershock came the same day and in the same area.

On February 1st, there was a 5.8 in Japan and a 5.3 in the Ionian Sea, a February 3rd, 6.5 (the Chinese say 7.0) quake in China, and a February 4th, 5.6 aftershock in China.

Many geologists fall back on the fact that there are usually quakes every day somewhere in the world, and that's true. What's not mentioned is that those are averages and do nothing to address the clustering found immediately after testing. These results follow the same trend found in the '88-'89 series and the current Indian and Pakistani tests.

For more information, contact National Earthquake Center, Golden, Colorado. Website: httpp://

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