Yesterday morning our area experienced an earthquake. Not that I felt it, fast asleep in my bed, nor did the cats piled on it to keep warm in these freezing nights. The first I heard of the event was when I read the following message posted on one of my near neighbour’s facebook page:
“Have just been woken up with the wardrobe shaking, our first earthquake tremor, has anyone else felt it? Or am I going mad?”
My neighbour doesn’t seem to be the type to go mad so I checked up on the web and found that there had indeed been an earthquake – in fact, several shocks.
This is what our regional paper “Il Tirreno” said about it:
On the same day that marked the thirtieth anniversary of our last major earthquake warning the people of Garfagnana and Mediavalle (where we are) experienced an unwelcomed wake-up call.
From 3.20 am with an epicentre in the Emilian- Tuscan Apennines there have been over 25 seismic shocks. At 5.27 the first shock to be higher than magnitude 2.5 (at 3.2) was registered. At 7.51 am the biggest shock was felt with magnitude 4.1 and with a lesser one at 8.03 am at magnitude 3.2. The epicentre was localized at a depth of 9 kilometres in the Pistoia region near Castiglione dei Pepoli, Camugnano and Vermio. The Mediavalle area felt the earthquake only because of the seismic waves reaching it.
It’s weird because I was talking about earthquakes with a friend only a few days previously and mentioned that for the past two years we’ve had an earthquake in January and speculated whether we’d be hit again this year. (See my post on the 2013 earthquake at https://longoio2.wordpress.com/2014/08/07/guzzano-church-resurrection/)
Of course, the fact that damage was minimal, except to the nerves of those who felt it, is welcome but are seismic shocks becoming more frequent in Italy? Evidently they are, according to this table published by Italy’s earthquake monitoring department:
Year Tremors registered Tremors above magnitude 3
So there we are: earthquakes are getting more frequent over here. Why? It’s because the African tectonic plate is squeezing ever more against the tectonic plate on which Italy is placed. So not only is this country being invaded by refugees crossing the seas from Africa but also by geological phenomena from the same place.
What about the anniversary the newspaper mentioned? In 1985 there was a major earthquake alert after a number of smaller tremors. The Lucca authorities organized the evacuation of 100,000 persons from their houses in the Garfagnana region. Fortunately, the big one did not happen and everyone returned to their homes after a couple of days.
We are, however, expecting the “big one” at any time since, according to records, it tends occur every hundred years and the last one was in 1920 (See my post at https://longoio2.wordpress.com/2014/09/30/the-big-one/ on that one).
In case you weren’t quite sure about the Richter scale for measuring earthquake intensity here is a table:
|Descriptor||Richter Magnitude number||Damage caused by the earthquake||Frequency of occurrence (in the world – not here!)|
|Micro||Less than 2.0||Micro (very small) earthquakes, people cannot feel these.||About 8,000 each day|
|Very minor||2.0-2.9||People do not feel these, but seismographs are able to detect them.||About 1,000 per day|
|Minor||3.0-3.9||People often feel these, but they rarely cause damage.||About 49,000 each year|
|Light||4.0-4.9||Objects inside houses are disturbed, causing noise. Nothing is damaged.||About 6,200 each year|
|Moderate||5.0-5.9||Buildings that are not built well may be damaged. Light objects inside a house may be moved.||About 800 per year|
|Strong||6.0-6.9||Moderately powerful. May cause a lot of damage in a larger area.||About 120 per year|
|Major||7.0-7.9||Can damage things seriously over larger areas.||About 18 per year|
|Great||8.0-9.9||Massive damage is caused. Heavy objects are thrown into the air and cracks appear on the ground, as well as visible shockwaves. Overhead highways may be destroyed, and buildings are toppled.||About 1 per 20 years|
|Meteoric||10.0+||There are no records of anything of this size. The vibration is about the same as that of a 15 mi meteor.||Unknown|
What should be added is that, depending on where you live and related factors, a Richter rating does not necessarily tell you what damage can be done. The additional factors in my opinion are these:
- Type of seismic waves hitting one: lateral – vertical – undulating – all these waves of the same intensity will produce different effects.
- Type of building construction. Very modern anti-seismic buildings or (interestingly) older buildings (because of their flexibility – especially if there is a lot of wood or old stone) will withstand earthquakes with less damage. Buildings most at risk are those standard reinforced concrete or breeze block ones built in the sixties and seventies.
- Physical state of person. Many victims of earthquakes are caused through heart attacks and the like. It’s clear that physically and mentally fitter people will be able to survive better.
- Emergency training. People who know their emergence drill will obviously be better prepared for what happens. As I’ve had to go through fire drills in UK public buildings I’ve worked in so I’ve had to go through earthquake drills in schools here. In case you’re didn’t know what the drill is here it is:
Finally, as President F. D. Roosevelt famously said “The only thing we have to fear is fear itself”.
So “what me worry?” There are plenty of things that can finish one off sooner than a major earthquake and I won’t’ even start to name them here!