Earthquakes and Volcanoes - I Feel the Earth Move Under My Feet

[C. Flower]

A continuation of an old Machine Nation thread, in which reports of earthquakes were recorded.

I just came upon this excellent site which maps earthquakes globally in the last 7 days.

It shows a string of earthquakes from north america to Indonesia and also in the Caribbiean and gives a real impression of how the earth's crust is shifting.

http://earthquake.usgs.gov/earthquakes/recenteqsww/

Now here's a question - does sea temperature change affect submarine geoology/ plate movements in any way

[C. Flower]

This shows the fault lines between plates.

(First posted in Tok. Jan 17th 2010)

[C. Flower]

REPLY BY IBIS

A continuation of an old Machine Nation thread, in which reports of earthquakes were recorded.

I just came upon this excellent site which maps earthquakes globally in the last 7 days.

It shows a string of earthquakes from north america to Indonesia and also in the Caribbiean and gives a real impression of how the earth's crust is shifting.


http://earthquake.usgs.gov/earthquakes/recenteqsww/

Now here's a question - does sea temperature change affect submarine geoology/ plate movements in any way ?

It does - indeed, lots of things do. The tension in an earthquake-prone fault is balanced against the pressure of the overlying atmosphere, earth, and water. See here for a fuller summary.

[C. Flower]

POSTED BY EVERCLOSERUNION

A continuation of an old Machine Nation thread, in which reports of earthquakes were recorded.

I just came upon this excellent site which maps earthquakes globally in the last 7 days.

It shows a string of earthquakes from north america to Indonesia and also in the Caribbiean and gives a real impression of how the earth's crust is shifting.


http://earthquake.usgs.gov/earthquakes/recenteqsww/

Now here's a question - does sea temperature change affect submarine geoology/ plate movements in any way ?

It does - indeed, lots of things do. The tension in an earthquake-prone fault is balanced against the pressure of the overlying atmosphere, earth, and water. See here for a fuller summary.

Loving those lines. Hundreds of miles away from Ireland, just the way I like them.

[C. Flower]

Not always so far. I was taught that Ireland is the result of a collision between land masses that were "european" and "american".

I guess that the "suture" on this map might be something to do with the join.



http://www.tcd.ie/Geology/staff/chew...%20Ireland.php

[C. Flower]

POSTED BY IBIS

Not always so far. I was taught that Ireland is the result of a collision between land masses that were "european" and "american".

I guess that the "suture" on this map might be something to do with the join.



http://www.tcd.ie/Geology/staff/chew...%20Ireland.php

Sure - Ireland started off on separate sides of an ocean called the Iapetus, with the north-west part of Laurentia (the same system of land as the Appalachians, Scotland, and Greenland), while the South was part of the microcontinent of Avalonia (Newfoundland, S. Ireland and England) - the latter collided first with Baltica (Scandinavia and parts of NE Europe) and then the two collided with Laurentia, closing the Iapetus.

However, that's 440-420 million years ago, and the Iapetus Suture was welded shut long long ago. It is no longer a plate boundary.

[C. Flower]

18.1.2010

There have been earthquakes reported today off the coast of Argentina and in Guatemala and also off the coast of Argentina.

http://upcoming.current.com/items/74...-no-damage.htm

[C. Flower]

POSTED BY THRANDUIL

Was trying to explain to my twelve year old niece all about the plates and how earthquakes happen today. She is very curious about all aspects of how things work, from the planets to quakes.

t does - indeed, lots of things do. The tension in an earthquake-prone fault is balanced against the pressure of the overlying atmosphere, earth, and water. See here for a fuller summary.

Then maybe Danny Glover wasn't being one hundred and ten percent illogical when he tried to make a connection between temperature change and the earthquake in Haiti (though i still believe 99.9% illogical is fair :lol. From that article though global warming should reduce the occurrence of earthquakes if it results in higher sea levels (and therefore more pressure on the zones between the plates), unless the pressure must come one way or another and doing this causes the pressure to build up - producing a higher intensity release of pressure instead of smaller and safer ones... It makes you appreciate just how finely tuned Earth is with these equilibria and delicate balances in place that such a small thing like a rainy day could destabilise that volcano in Montserrat (as the article states) causing an eruption or that a little teeny bit closer our planet is to the sun making a major difference in temperature possibly making it too hot for us to survive on.

[C. Flower]

I haven't been able to find any chronology of earthquakes over the last few centuries and haven't a clue if they are particularly frequent now. It seemed to me that there were a lot, 2008-2009, but its possible that the tsunami made the media, and me, more concious of them.

[Xray]

i am sure if they were becoming significantly more common we would hear about it. I suspect it is just on of those things, it has happened before and will again.
We are very lucky. I remember the one in the Irish sea in the 80s, I was in bed in the morning and the house started shaking, I thought it was a truck or plane passing.

[5intheface]

Yes I remember my late Mother was visiting her sister in Santry and was woken by that, she just assumed it was a bomb then remembered she wasn't at home.

[Fraxinus]

There was a small one in Donegal a few weeks back but how is this possible if the nearest fault line in way off. Or do the massive earthquakes occur around the fault lines while smaller ones can happen anywhere? I wish I paid attention in earth science.

[estouxim]

Another one today - Turkey, 5,9

72 quakes above magnitude 5 in the last 7 days

I know quakes are happening all the time, but so many, so strong?

[C. Flower]

Thranduil's post is interesting, but the sea level change I believe is mainly due to the expansion of the water as it gets warmer. Sea temperatures worldwide in 2009 were on average highest "since records began", whenever that was.

Estouxim, I have also felt that we have had a lot of earthquakes over the last year or so, and logged them on a thread on Machine Nation, then Tok! and now here. I have read that some are cyclical and maybe expected to be very active every 120 years or so. There are little oscillations of the planet - maybe they have an effect?

I was fascinated to see that the Chilean earthquake had an effect on the length of the day (however infinitisal) and gave the entire planet a little jolt along its regular journey.

I understand the questioning as to whether there could be some human interention in this. In the case of Haiti, where the earthquake was so close to the surface and so close to the city, the question came up in my mind. But Haiti, like all of the earthquakes, took place on a known fault line where earthquakes are expected.

I would like to see some kind of timeline of earthquakes and their intensity over the last couple of hundred years, but it seems highly unlikely that such data exists.

The planet is not an inert thing, and while it has regular habits, some of these habits are violent, sudden and difficult to predict. What we can do is prepare for some of them. In earthquake zones the type of construction used has an enormous effect on the death rate if a serious earthquake occurs.
In answer to Fraxinus' question, Ibis said that Ireland's fault line has long ago sealed up, but I have heard geologists say that Ireland is moving slowly (Mary Harney must be pleased) towards the United States. The earth's crust is relatively very thin and its inside very hot and volatile, so i suppose the whole thing moves around to some extent.

There was an interesting thread also recently at Machine Nation from Evotingmachine, discussing "why the centre of the earth is still hot". The answer is fascinating and complex and I'll link it here some time.

[C. Flower]

http://www.breakingnews.ie/world/doz...ey-449180.html

An earthquake over 6 on the Richter scale hit Turkey this morning and flattened at least one village.