The geology that causes Italy's spine to quake

The cluster of earthquakes that have hit Italy this year are the latest in a long history of destruction. Italy sits on the boundary where the African tectonic plate is diving down beneath the Eurasian plate

For people living along Italy's picturesque Apennine mountain spine, these are worrying times. Since 24 August there have been three significant earthquakes in the region, the most recent of which was the magnitude 6.6 Norcia quake, on Sunday 30 October. Add to this the thousands of smaller aftershocks, and right now the Apennines feel very unstable. So why is the backbone of Italy being pummelled repeatedly?

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