I live very near to the epicentre (about 25km away), and was awake at the time. Pretty much straight away it was clear that it was an earthquake, and reasonably strong at that. I felt rather schocked intially, especially as there seemed to be a bang at the beginning and it felt stronger than the last (in 2002). But after about five or ten seconds, I felt that it wasn't going to get any stronger (don't know whay I felt this, just did), and I started actually enjoying the feeling of being shaken.
After it had stopped, it occured to me that it could, possibly just, be an explosion, as there a a number of refineries and chemical plants relatively nearby. I went upstairs and spoke to everybody who had woken up and looked out the windows. But there was no smoke or flames on the horizon, so it was a stupid worry really. Oddly, roadworks started outside my house today, so the earth has been shaking all day.
However, I don't think my experience has helped bring earthquakes in general into my understanding as a life-threatening thing. I mean, they are explicable, and I know that they can and do kill many people. But the sheer meaninglessness of an earthquake is difficult to process, if not impossible, when it causes death and destruction. I can only guess that it feels very emptying, as there is no reason with which we can replace our loss, and really no closure. Losing somebody, or even something, in that way must be very individual as each person seeks their own reason and understanding where none exists. Member of the Anti-Fabulousness League since 1987.
Most people believe reality is real, as exemplified by the firmness underfoot. When the firmness underfoot melts away, so does the perception of reality.
In the SF bay area, small quakes are omnipresent, with little effect other than subconsciously. But all of the big quakes, say greater than 5.8, cause little studied psychological effects. But it's in the big ones where it finally becomes obvious.
After the '89 jolt, the typical total quiet of the water and weather took hold. There were huge, drunken parties in the streets everywhere i went. Kind of a celebration of survival.
After the first exhilaration wore off, the level of general depression was astounding. My amateur analysis was simply that most people can't handle their basis of reality being destroyed. (In a real earthquake, that's what happens, as there is no longer a ground to stand on.) i noticed that other natural disasters had less mood swing attached.
It's one thing when your house shakes a bit. It's quite another when your base of reality no longer exists. and you don't forget, as you've seen everything happen in slow motion.
Aside: i was in the parking lot tailgating at Candlestick Park in '89. i happened to have turned away from the stadium when the quake hit. i watched in awe as thirty rows of car roofs swelled and ebbed like the giant waves at Mavericks. i knew instantaneously what was happening, and rode the wave just as if i was surfing. When it was over, i continued the tailgate party like everyone else. It took about 10 minutes to digest what had just happened, and i started to wonder about where my son might be. It took the first white faces descending from the upper deck of the stadium to bring me back to reality, and i split quickly. on the drive home through back streets of SF i realized how huge the damage as going to be. (It was 7.1 if i recall.)
When i realize it would take less than a 6.0 to devastate anywhere in Europe, where we just normally ride through a 5.8 or even 6.0, i get concerned. Skennah Kowa
When i realize it would take less than a 6.0 to devastate anywhere in Europe, where we just normally ride through a 5.8 or even 6.0, i get concerned.
It's a case of bringing risk down to roughly the same tolerable level, in different circumstances. We have met the enemy, and he is us — Pogo
Previously, we've touched upon about earthquakes in Switzerland. Historically we also know about Italy, both in the south but also north (Friuli, Umbria) and even Portugal (which I don't really understand at first glance). The only European country which has to deal with major earthquakes at a fairly regular basis is Greece.
Anything above 7.0 Richter scale with an epicentre nearby a major city may well give abhorrent chaos in countries where modern architecture has not been previously tested by a big quake. I'd suspect some hazard evaluation should be available at the seismological services in each country, but I already have a PhD to finish...
How strong have the earthquakes been in Switzerland? Magnitude 4?
There are earthquakes in the Alps, but the major plate boundary (responsible for the Lisbon earthquake) is in the Southern Mediterranean (which explains Turkey, Greece, Southern Italy and Southern Spain).
Though there is this:
Plate tectonics - Wikipedia, the free encyclopedia
Not all plate boundaries are easily defined. Some are broad belts whose movements are unclear to scientists. One example would be the Mediterranean-Alpine boundary, which involves two major plates and several micro plates.
The Basel earthquake has been estimated with a intensity of IX, which can probably be correlated to a Richter scale (or the more accurate Seismic Moment). I found a hazard analysis on Basel here wherein they write:
Earthquake Scenarios for the City of Basel
The calculated scenarios are an intensity VII - VIII earthquake and one of intensity IX. These represent the expected value with return period of 475 years generally used in building codes, and the intensity of the earthquake in 1356.
Meaning, the building codes do no provide for earthquakes the magnitude of the 14th century Basel quake, and the estimated damage is considerable (Fig 1). How likely is it that we'll have another one? Don't know, but the very fact that one happened should bear caution - it's a known unknown. If stress can build up in that region to such levels, it can happen again.
The simplification of the plates in the picture works as a first approximation concept - there is no nicely defined 8 pixel line, especially when it concerns converging plates which is a very messy process. The idea one would get from the picture above when focussed on the African-EuroAsian plate margins is completely wrong. One would have to zoom in on the Mediterranean, start here.
Yes, most of the tectonic action is concentrated at a particular zone and you're correct that the majority of the major earthquakes will be centred around the Mediterranean countries. The uncertainty is: what's the extent of major seismic event towards the north? For now, we know at least Basel, and the north of Italy, can be affected. Although, for Basel, it's not clear to me if it's because of plate convergence to the south or by normal faulting as a response to crustal loading.
To address the original comment, Germany doesn't appear on Wikipedia's List of deadly earthquakes since 1900.
Portugal had a magnitude 7.8 in 1969 which killed 13 people (both the earliest and strongest on the list for Portugal, which suggests a gap in the data).
Spain has one in magnitude 5.3 in 1997 which killed one person.
The strongest on the list for France was a magnitude 4.2 which killed one person in 2001. The weakest and earliest is a 3.5 in 1983, also killing one.
Switzerland is not on the list, and neither is Austria.
Italy has 31 earthquakes on the list. The earliest is a magnitude 6.8 in 1905, killing about 1200 people. The weakest is a 4.2 in 1987, killing 2. The strongest is a 7.2 in 1908, killing 80 thousand.
Greece has 39. The earliest and strongest is a magnitude 8.2 in 1903, killing 2. The weakest is a 4.6 in 1978, killing 1. The deadliest is a 7.2 in 1953, killing 600.
Japan has 74 earthquakes on the list. The earliest is a 7.0 in 1900. The strongest is an 8.4 in 1933, killing 3,000. The deadliest is the 1923 Kanto Earthquake, magnitude 7.9 killing 140 thousand.
The US (excluding "minor outlying islands") has 29. The earliest, strongest and deadliest is the 1906 SF earthquake, 7.8 killing 1200 people. We have met the enemy, and he is us — Pogo
The most powerful recent quakes were
However, I recall reading an article by some geologists critical of the ruling assumption that the central part of the rift zone shifts in a 'lubricated' way -- that assumption is unproven, and that would imply the possibility of strong earthquakes with a low frequency. I.e., what the USA had at New Madrid in 1812 (incidentally the strongest for the contiguous states in recorded history), and China at Tangshan in 1976. Such low-frequency events are definitely missing from risk calculations, especially for high-rises, which haven't been around for long. *Traitor*, n. A benighted individual who perceives an illusory distinction between serving his nation and abetting the criminals who govern it.
We know that large magnitude events have occurred prior to the 20th century. Has modern architecture (eg. flats and office blocks) in these countries withstood a direct hit of major earthquakes? No - because they're untested. There were no major events in this time period. And Messina was bad enough.
Developments and architecture work on hindsight, retrospection and, worse, amnesia - not foresight. I've used the housing planning in England's river stormbeds during last year's floodings as example of that. I don't believe it's really that different for earthquakes.
