The year of 365AD

19 February 2015

This is the year of a big earthquake in the central Mediterranean area, an earthquake that produced a tsunami wave that caused widespread destruction as far afield as Cyprus and Egypt. It is described graphically by the Roman historian Ammianus Marcellus – see for starters

It was preceded by furious and incessant lightning – what does that mean? The sea retreated a considerable distance going by his words, stranding boats and marine life. Then the waves came crashing forwards, rising and swelling up and destructively smashed against the coast and any homes and buildings near the shores. Thousands were drowned and it is remarkably similar in effect to the earthquake and tsunami wave that recently struck Japan – wreaking havoc along the coastline.

The Japan earthquake was blamed on a fault line at a plate boundary in the NW Pacific. Geophysicists say that western Crete, the epicentre of the earthquake, also lies on a fault line – and it is believed that one plate is subducting under another plate. The situation therefore seems to differ. However, the Boxing Day tsunami that was generated by an earthquake off the coast of Aceh Province in Indonesia, may also have been a plate boundary – but nobody has yet suggested there was subduction. It was put down to slippage, one side of the fault line dropping in relation to the other side – and displacing ocean water.

Recent research has shown ancient shorelines in the region changed considerably with the earthquake in western Crete – ten metres of uplift occurred. This is a huge displacement of rock strata – and it all happened with one jolt, suddenly.

Alexandria was affected by the tsunami wave – see … which is based on a paper in Nature Geoscience (in 2008). There was another paper in Nature Geoscience in 2013 – see  … which describes research done on megaturbides. These are found in sediments on the bottom of the sea and are caused by ground acceleration from seismic events, caused it is thought by tsunami waves. In the Ionian Basin (the Aegean) the sediments are very thick and are said to span the whole period from the Jurassic to the Holocene, some 200 million years. The upper layers of sediment, which themselves are extremely thick, were tested, even though they are thought to go back to Late Miocene. The most recent megaturbide, or the most significant of the recent, was until recently attributed to the Thera volcano – and was used to demonstrate how powerful that particular eruption was. However, the trajectory did not seem to quite fit so in recent years some geophysicists have tried to rope in Etna instead. Now they are looking at the earthquake at 365AD – which happened nearly 2000 years after Thera.

When they came to actually dating the megaturbide event they came up with a date somewhere between 215 and 547AD – which would include a multiple of sins. The implication is that the 365 earthquake was disastrous enough to cause mayhem in the eastern Roman Empire. At … they call the 365 earthquake after Kourian, a town on Cyprus that was destroyed by the tsunami wave.

Skip to content