Two recent events have brought this question to light, Deadly tsunami strikes in Pacific. If so; why? Is there a connection between them and an unknown underlying cause?
Is frequency of earthquake tsunamis increasing?
- Thread starter common_sense_seeker
- Start date
No-one interested in the possiblity of a frequency increase. Too early to tell?
they have nothing to do with eachother. They are miles apart. Now the series of earthquakes in indonesia aparently ARE related, ie they are part of a series which started 10 years ago and will aparently cuminate in a mag 10 in sumatra? (i cant rember where it was surposed to end)
It's quite eerie with the ability of accurate predictions of where the next hit will be, don't you think?
It's a horrible subject. I'm going to concentrate on something else for a while.
I'd be interested in reading the full article. Can you provide a link?
a senario we did in a lecture was what do you do if the adelaide falt line had a major quake. Basically we lose every major hospital except tha adelaide and the metro area is divided into thirds with only the CBD itself having any access to the royal Adelaide hospital. Botom line is we would be royally fucked and thats ignoring the actual injuries should something like AAMI stadium or Adelaide oval happen to be full when it struck
http://www.msnbc.msn.com/id/24096212/
According to the chart on this page : http://neic.usgs.gov/neis/eqlists/eqstats.html
It does appear the average number of Earthquakes per year has increased by about 8-9000 ending at a total of 31,777 in 2008 and started at 22,256 in the year 2000. In the 1990s, the numbers were even lower...http://neic.usgs.gov/neis/eqlists/info_1990s.html
16,590 in 1990, and 20,832 in 1999. So yes it does appear Earthquake occurrences are rising, and steadily. Now the question is, why?
It does appear the average number of Earthquakes per year has increased by about 8-9000 ending at a total of 31,777 in 2008 and started at 22,256 in the year 2000. In the 1990s, the numbers were even lower...http://neic.usgs.gov/neis/eqlists/info_1990s.html
16,590 in 1990, and 20,832 in 1999. So yes it does appear Earthquake occurrences are rising, and steadily. Now the question is, why?
Did you read the link you supplied? The answer to the question raised in the original post is right there.
As more and more seismographs are installed in the world, more earthquakes can be and have been located. However, the number of large earthquakes (magnitude 6.0 and greater) has stayed relatively constant. See: Are Earthquakes Really on the Increase?
From that imbedded link,
Are Earthquakes Really on the Increase?
We continue to be asked by many people throughout the world if earthquakes are on the increase. Although it may seem that we are having more earthquakes, earthquakes of magnitude 7.0 or greater have remained fairly constant.
A partial explanation may lie in the fact that in the last twenty years, we have definitely had an increase in the number of earthquakes we have been able to locate each year. This is because of the tremendous increase in the number of seismograph stations in the world and the many improvements in global communications. In 1931, there were about 350 stations operating in the world; today, there are more than 8,000 stations and the data now comes in rapidly from these stations by electronic mail, internet and satellite. This increase in the number of stations and the more timely receipt of data has allowed us and other seismological centers to locate earthquakes more rapidly and to locate many small earthquakes which were undetected in earlier years. The NEIC now locates about 20,000 earthquakes each year or approximately 50 per day. Also, because of the improvements in communications and the increased interest in the environment and natural disasters, the public now learns about more earthquakes.
We continue to be asked by many people throughout the world if earthquakes are on the increase. Although it may seem that we are having more earthquakes, earthquakes of magnitude 7.0 or greater have remained fairly constant.
A partial explanation may lie in the fact that in the last twenty years, we have definitely had an increase in the number of earthquakes we have been able to locate each year. This is because of the tremendous increase in the number of seismograph stations in the world and the many improvements in global communications. In 1931, there were about 350 stations operating in the world; today, there are more than 8,000 stations and the data now comes in rapidly from these stations by electronic mail, internet and satellite. This increase in the number of stations and the more timely receipt of data has allowed us and other seismological centers to locate earthquakes more rapidly and to locate many small earthquakes which were undetected in earlier years. The NEIC now locates about 20,000 earthquakes each year or approximately 50 per day. Also, because of the improvements in communications and the increased interest in the environment and natural disasters, the public now learns about more earthquakes.
How many seismograph stations were installed from 2000 to 2008?
Can We Tell Yet (earthquake tsunamis increasing)?
I have read some articles where the author says thinning ice sheets over Greenland could trigger quakes and the resultant tsunamis.
I have not read the same for Antarctica, or anywhere else, however.
We may need a longer span of time to collect data, because increases in occurrences can sometimes happen without a nexus to anything else.
But if this is in fact happening, it is a function of more earthquakes near the oceans or under them.
One hypothesis might be that water is heavier than the ice that is melting, so more stress is being put on land under the oceans that are getting heavier.
It would show up where that factor was near fault zones. No?
A study might, with enough data, provide a nexus to a real and present increase for those reasons.
I have read some articles where the author says thinning ice sheets over Greenland could trigger quakes and the resultant tsunamis.
I have not read the same for Antarctica, or anywhere else, however.
We may need a longer span of time to collect data, because increases in occurrences can sometimes happen without a nexus to anything else.
But if this is in fact happening, it is a function of more earthquakes near the oceans or under them.
One hypothesis might be that water is heavier than the ice that is melting, so more stress is being put on land under the oceans that are getting heavier.
It would show up where that factor was near fault zones. No?
A study might, with enough data, provide a nexus to a real and present increase for those reasons.
yeah these so called earthquakes causing tsunamis are being monitored much more closely and information being widespread all over the Globe about its conditions all around ... at this stage it would be hard to deduce if they did indeed increase in frequency or if it is a result of closer monitoring (which I think it is).
Here's a neat map of tsunami occurances in USA at their respective dates.
Here's a neat map of tsunami occurances in USA at their respective dates.
There was a powerful earthquake in the Kermadec Trench, northeast of New Zealand, sometime in the 1450's; it created a tsunami that hit the east coast of New Zealand. It was 100 feet high when it hit the coast, and had a run-up height of about 300 feet or 90 metres. It destroyed all the Maori pas (forts) and kianga (sea-shore settlements) in the north and east of the country, and caused the abandonment of the coasts for about a century. The effects of this tsunami would surely have been noticed in a reduced form across the entire Pacific, including the west coasts of the Americas.
I have noticed that after an earthquake, the rescue efforts often seem to be hampered by bad weather.
Is this just sod's law, or is there a connection?
Is this just sod's law, or is there a connection?
Last edited:
Ophiolite
Valued Senior Member
There is a clear correlation between bad weather and the presence of large teams of television reporters. The latter are skillful at seeking out the most devestated views and filming these under the most adverse conditions, using portable fans if necessary, to create that windswept look. Cameramen are also adept at shaking their cameras to exagerate the magnitude of aftershocks.