On Thursday 12 July 2012, at 3.22 am local time (1.22 am GMT) an Earthquake occurred in the Auvergne Region of France, roughly 19 k southwest of Clermont-Ferrand, according to the Centre Sismologique Euro-Méditerranéen, who reported the quake as measuring 3.0 on the Richter Scale and occurring at a depth of 2 km. A quake of this size is highly unlikely to have caused any damage or casualties, but may have been felt by people locally.
Map showing the location of the 12 July quake. Centre Sismologique Euro-Méditerranéen.
France is not noted for its Earthquake activity as it seldom suffers from large-scale quakes, however small tremors are not uncommon there; this being the tenth quake with a magnitude of greater than 2.0 recorded in France this month. The most obvious cause of these quakes is the impact of Africa into Europe from the south, which is pushing Italy into central Europe and causing uplift and folding in the Alps. France also suffers tectonic stresses to a lesser extent from the effects of small spreading centers under the Rhine, the North Sea and the Bay of Biscay. In addition the country is suffering the effects of glacial rebound; much of Europe was covered by thick glaciers until the end of the Pleistocene about 10 000 years ago. This was particularly true in the north and in high altitude areas such as the Alps, the Pyrenees and the Massif Central. These glaciers pushed the rocks of the lithosphere down into the underlying mantle, and now that they are gone the rocks are slowly rebounding. It is seldom possible to establish a single one of these factors as the cause of a quake, and most are probably the result of the interaction of a number of sources of stress.
If you felt this quake you can report it to the Centre Sismologique Euro-Méditerranéen here.
See also Modena Plane hit by second major Earthquake, Earthquake beneath the English Channel, Earthquake on the Modena Plane, northern Italy, An Earthquake off the coast of Margate, 8 April 2012 and Earthquakes on Sciency Thoughts Youtube.
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