Which areas of France are most at risk from earthquakes?

Reader Question: Which areas of France have had the strongest earthquakes in the past? Which are most at risk?

It is important to identify what we mean by ‘France’ as France’s overseas departments and territories in the Caribbean and the Pacific are more prone to seismic activity than mainland France and have recorded many earthquakes. 

All earthquakes in France’s history which measured 7 or higher on the Richter scale were in Martinique, Guadeloupe, or New Caledonia (although in the latter the epicentres were in the ocean with resulting damage being caused by the ensuing tsunami).

Looking at metropolitan France (the mainland and Corsica) things are different. 

Thousands of earthquakes occur each year but the majority are so small they are barely detectable by humans. 

Two recent small earthquakes that made the news were in Perpignan and Dordogne.

Read more: ‘Alarms went off everywhere’: Light earthquake felt in Perpignan

Around 30 earthquakes per year in metropolitan France measure high enough on the Richter scale for humans to feel them, however even these are unlikely to cause damage. 

France’s Institut de Radioprotection et de Sûreté Nucléaire (IRSN) has its own ranking system of 1-5 (‘very light’ to ‘strong’) for which areas in France are most at risk of earthquakes. 

Nowhere on the mainland has a level 5 risk - this is seen only in the Caribbean - although some, mostly mountainous, areas are placed at level 4, described as ‘medium’ risk.

These are found mostly in the Pyrenees and Alps.

You can see a map in the article below: 

Read more: MAP: 4,000 earthquakes a year in France; where, and what risk level?

Largest recorded earthquakes in France

The highest recorded earthquake in mainland France was in the Vendée department in 1799, measuring 6.4 - 6.5 on the Richter scale. 

It caused serious economic damage, destroying thousands of buildings although there were not any recorded deaths.

More powerful earthquakes near France’s Alpine border (in Liguria, Italy; and Valais, Switzerland) have been recorded.

The largest earthquake recorded in Central Europe, near Basel, Switzerland in 1356, affected some parts of France.

More recently an earthquake in 1946 in Provence killed 46 people. It measured 6.2 on the Richter scale.