Fortean Times Message Board

Hugo Cornwall · Gone Slightly Mad! Joined: 18 Jun 2002 Posts: 2201

Have there been studies of a correlation between perihelion and earthquakes?

Just from my own meandering memory, I'm certain we seem to get more earthquakes this time of year (Turkey, Albania, Greece, Afghanistan, and now Sumatra) around Xmas and New Year than during the period after the start of summer (aphelion of our orbit).

Could it be a slight increase in the Solar tidal effect as we swing away from the sun around winter solstice?
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rynner · Posted: 27-12-2004 16:31 Post subject:

Perhaps. The Earth is nearer the sun at this time of year. (The fact that's it's the northern winter is to do with the tilt of the Earth's axis, not the distance from the sun.)

It was also full moon last night, giving increased tidal stesses.

lopaka · Tawdry Yank Cliche Joined: 17 Sep 2001 Posts: 2241

Hugo: I'd be willing to play with numbers a little (though it's likely to take a little while. I have the raw data but no way to easily sort it). Do you have a specific timeframe (over/under one week from perihelion/aphelion) you were thinking of as parameters for a study? As far as events to use , I'd probably use the USGS standard for 'significant', >6.5 and/or deaths and/or widespread damage. Though obviously that's different than 'earthquakes'.

Thoughts?
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Emperor · Posted: 27-12-2004 16:53 Post subject:

There have been studies correlating volcanic activity with ice core information and it appears that volanic activity rises when the crust is being loaded and unloaded (at the beginning and end of glaciations respectively) - e.g. the Toba mega-eruption happened during the shift into the last Ice Age.

Clearly if we can see this kind of thing in records which are not going to be very finegrained but it does show that shifts in the stresses on the crust can have significant effects.
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Emps

The wakeful trump of doom. - "The Hymn" Milton.

I've seen things you people wouldn't believe... All those moments will be lost in time, like tears in rain. Roy Batty

Emperor · Posted: 27-12-2004 17:02 Post subject:

I did a quick Google - some random informaiton:

There is seasonla variation in Japanese earthquakes possibly related to snow load:
http://www.ep.sci.hokudai.ac.jp/~heki/documents/snowquake.htm

There has been some suggestions that it might correlate to changes in geomagnetism:
http://www.cosis.net/abstracts/EAE03/13108/EAE03-J-13108.pdf

It has been known for a while that filling reservoirs can lead to earthquakes:
http://projecteuclid.org/Dienst/UI/1.0/Summarize/euclid.jap/1085496605

rynner · Posted: 27-12-2004 17:51 Post subject:

There was another Xmas earthquake, which thankfully didn't hurt anyone.

It was in Antartica (sorry to have to bring up penguins again! Very Happy

)

Penguins escape huge earthquake
An earthquake on a remote Antarctic archipelago home to 850,000 King Penguins was the strongest on earth in four years, seismologists say.
The quake hit 400km (250 miles) off the Macquarie Islands on Friday, measuring 8.1 on the Richter scale.

Penguins appear to have escaped a major disaster as the quake occurred deep under the sea, far from inhabited land.

There were no tsunamis, or large tidal waves, because the quake moved horizontally rather than vertically.

The tremors were felt in Tasmania, 1000km (600 miles) away, but because the epicentre was 10km underground, few observers noticed the initial quake.

Buildings on the islands shook for 15 seconds, seismologist Cvetan Sinadinovski said.

"If this had happened underneath a population centre it would probably have destroyed a whole city," he said.

The quake was the biggest anywhere on earth since an 8.4-magnitude tremor off the coast of Peru in June 2001. That killed 74 people.

Friday's earthquake was caused by the collision of two of the major tectonic plates which make up the earth's crust layer, the Indo-Australian and the Pacific plates.

The last quake of a similar magnitude in the Macquarie region was in 1924, Mr Sinadinovski said.

Despite its size, 22 staff of the Australian Antarctic Division slept through the tremors.

"Nobody felt anything," a spokesman said.

10 BIGGEST QUAKES SINCE 1900
Chile, 1960: 9.5
Alaska, 1964: 9.2
Alaska, 1957: 9.1
Kamchatka, 1952: 9.0
Near Ecuador, 1906: 8.8
Alaska, 1965: 8.7
Tibet, 1950: 8.6
Kamchatka, 1923: 8.5
Indonesia, 1938: 8.5
Kuril Islands, 1963: 8.5
Source: US Geological Survey

http://news.bbc.co.uk/1/hi/world/asia-pacific/4123927.stm

Emperor · Posted: 27-12-2004 17:56 Post subject:

There was an earlier quake in Tasmania which some siesmologists think may have contributed/presaged the main one:

www.forteantimes.com/forum/viewtopic.php?p=478531#478531

which is interesting as there were a number of mystery whale and dolphin beachings in Tasmania at the end of November:

www.forteantimes.com/forum/viewtopic.php?p=469685#469685

A link?
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Emps

The wakeful trump of doom. - "The Hymn" Milton.

I've seen things you people wouldn't believe... All those moments will be lost in time, like tears in rain. Roy Batty

Hugo Cornwall · Gone Slightly Mad! Joined: 18 Jun 2002 Posts: 2201

Purely from gut feeling, period of up to three weeks after solstice.

I'm not sure that the physics is holds water but wouldn't the stresses be higher moving out of the gravity well as we decelerate away from the sun?

As a complete side bar, why does the illumination of the face of the moon affect tides? The moon is always there as a gravitic centre... something I've never seen properly explained.
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"Somewhere, something incredible is waiting to be known." Carl Sagan

Emperor · Posted: 27-12-2004 22:24 Post subject:

Goldstein · Older than the Dark Lord Joined: 09 Dec 2001 Posts: 332

Has anyone noted yet that it was a year to the day since the last big earthquake, in Bam, Iran? Shocked

That one wasn't anywhere near as big on the Richter scale, and didn't kill (m)any tourists, but the death toll was, IIRC, comparable to this one simply because the epicentre was in a city...

Surely there's material for some very scary theories there...

Something a friend of mine said: perhaps this was the revenge of the Little People for their grave discovery/desecration... Shocked

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lopaka · Tawdry Yank Cliche Joined: 17 Sep 2001 Posts: 2241

There's a site that's been trying to use a list (a very selective one, I hasten to add) about recent Asian/Pacific earthquakes on the 26th of the month, not just December. It's all nonsense, but it's been making the rounds...

lopaka · Tawdry Yank Cliche Joined: 17 Sep 2001 Posts: 2241

While searching the MB on an unrelated topic I came across this that Emps posted last year * Nice day for an eruption *, with the part that caught my eye being:

Emperor · Posted: 10-01-2005 17:33 Post subject:

lopaka: I think it would be safe to assume that similar crustal stresses work on both volcanoes an earthquakes - we just have a better understanding of the timedepth of volcanic eruptions from ice cores.
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Emps

The wakeful trump of doom. - "The Hymn" Milton.

I've seen things you people wouldn't believe... All those moments will be lost in time, like tears in rain. Roy Batty