HISTORIC TSUNAMIS

Recorded Historic Tsunamis - Part 1

This article is telling about the lists of notable historic tsunamis, which are sorted by the date and location that the tsunami occurred, the earthquake that generated it, or both.

Because of seismic and volcanic activities at tectonic plate boundaries along the Pacific Ring of Fire, tsunamis occur most frequently in the Pacific Ocean, but are also worldwide natural phenomena. Tsunamis are possible wherever large bodies of water are found, including inland lakes, where they can be caused by landslides and glacier calving. Very small tsunamis, non-destructive and undetectable without specialized equipment, occur frequently as a result of minor earthquakes and other events.

As early as 426 BC, the Greek historian Thucydides inquired in his book History of the Peloponnesian War (3.89.1-6) about the causes of tsunamis. He argued rightly that it could only be explained as a consequence of ocean earthquakes, and could see no other possible causes for the phenomenon.^[1]

Crete and the Argolid and other locations were destroyed by a tsunami caused by the eruption of Thira, which destroyed Minoan civilization on Crete and related cultures in the Cyclades and in areas facing the eruption on the Greek mainland such as the Argolid.

During the Persian siege of the sea town Potidaea, Greece, in 479 BC,^[2] the Greek historian Herodotus reports how the Persian attackers who tried to exploit an unusual retreat of the water were suddenly surprised by "a great flood-tide, higher, as the people of the place say, than any one of the many that had been before". Herodotus attributes the cause of the sudden flood to the wrath of Poseidon.^[3]

Here are some facts provided by the history about the tsunamis:

Tsunamis - Before 1000 AD

 

1) 6100 BC: Norwegian Sea

Main article: Storegga Slide

The Storegga Slides occurred 100 km north-west of the Møre coast in the Norwegian Sea, causing a very large tsunami in the North Atlantic Ocean. This collapse involved an estimated 290 km length of coastal shelf, with a total volume of 3,500 km³ of debris.^[4] Based on carbon dating of plant material recovered from sediment deposited by the tsunami, the latest incident occurred around 6100 BC.^[5] 

In Scotland, traces of the subsequent tsunami have been recorded, with deposited sediment being discovered in Montrose Basin, the Firth of Forth, up to 80 km inland and 4 metres above current normal tide levels.

 

2) 1600 BC: Santorini, Greece

Main article: Minoan eruption

The volcanic eruption on Santorini, Greece is assumed to have caused severe damage to cities around it, most notably the Minoan civilization on Crete. A tsunami is assumed to be the factor that caused the most damage.

 

3) 426 BC: Maliakos Gulf, Greece

Main article: 426 BC Maliakos Gulf tsunami

In the summer of 426 BC, a tsunami hit hard the Maliakos bay in Eastern Greece.^[6] The Greek historian Thucydides (3.89.1-6) described how the tsunami and a series of earthquakes intervened with the events of the raging Peloponnesian War (431-404 BC) and correlated for the first time in the history of natural science quakes and waves in terms of cause and effect.^[7]

 

4) 373 BC: Helike, Greece

An earthquake and a tsunami destroyed the prosperous Greek city Helike, lying 2 km away from the sea. The fate of the city, which remained permanently submerged, was often commented upon by ancient writers^[8] and may have inspired the contemporary Plato to the myth of Atlantis.

 

5) 365 AD: Alexandria, Eastern Mediterranean

Main article: 365 Crete earthquake

In the morning of July 21, 365 AD, an earthquake of great magnitude caused a huge tsunami more than 100 feet high. It devastated Alexandria and the eastern shores of the Mediterranean, killing thousands and hurling ships nearly two miles inland.^[9][10] The Roman historian Ammianus Marcellinus (Res Gestae 26.10.15-19) describes in his vivid account the typical sequence of the tsunami including an incipient earthquake, the sudden retreat of the sea and a following gigantic wave:

Slightly after daybreak, and heralded by a thick succession of fiercely shaken thunderbolts, the solidity of the whole earth was made to shake and shudder, and the sea was driven away, its waves were rolled back, and it disappeared, so that the abyss of the depths was uncovered and many-shaped varieties of sea-creatures were seen stuck in the slime; the great wastes of those valleys and mountains, which the very creation had dismissed beneath the vast whirlpools, at that moment, as it was given to be believed, looked up at the sun's rays. Many ships, then, were stranded as if on dry land, and people wandered at will about the paltry remains of the waters to collect fish and the like in their hands; then the roaring sea as if insulted by its repulse rises back in turn, and through the teeming shoals dashed itself violently on islands and extensive tracts of the mainland, and flattened innumerable buildings in towns or wherever they were found. Thus in the raging conflict of the elements, the face of the earth was changed to reveal wondrous sights. For the mass of waters returning when least expected killed many thousands by drowning, and with the tides whipped up to a height as they rushed back, some ships, after the anger of the watery element had grown old, were seen to have sunk, and the bodies of people killed in shipwrecks lay there, faces up or down. Other huge ships, thrust out by the mad blasts, perched on the roofs of houses, as happened at Alexandria, and others were hurled nearly two miles from the shore, like the Laconian vessel near the town of Methone which I saw when I passed by, yawning apart from long decay.^[9]

The tsunami in 365 AD was so devastating that the anniversary of the disaster was still commemorated annually at the end of the 6th century in Alexandria as a "day of horror."^[11]

Researchers at the University of Cambridge recently carbon dated corals on the coast of Crete which were lifted 10 metres and clear of the water in one massive push. This indicates that the tsunami of 365 AD was generated by an earthquake in a steep fault in the Hellenic trench near Crete. The scientists estimate that such a large uplift is only likely to occur once in 5,000 years, however the other segments of the fault could slip on a similar scale - and could happen every 800 years or so. It is unsure whether "one of the contiguous patches might slip in the future."^[12]

 

6) 684 AD: Hakuho, Japan (白鳳大地震)

Japan is the nation with the most recorded tsunamis in the world. The number of tsunamis in Japan totals 195 over a 1,313 year period (thru 1997), averaging one event every 6.73 years, the highest rate of occurrence in the world.

The Great Hakuho Earthquake was the first recorded tsunami in Japan. It hit in Japan on November 29, 684. It occurred off the shore of the Kii Peninsula, Nankaido, Shikoku, Kii, and Awaji region. It has been estimated to be a magnitude 8.4 ^[13] It was followed by a huge tsunami, but no estimates on how many deaths.^[14]

 

7) 869 AD: Sendai, Japan

Main article: 869 Sanriku earthquake and tsunami

The Sendai region was struck by a major tsunami that caused flooding extending 4 km inland from the coast. The town of Tagajō was destroyed, with an estimated 1,000 casualties.

 

8) 887 AD: Ninna Nankai, Japan (仁和南海地震)

On August 26 of the Ninna era, there was a strong shock in the Kyoto region, causing great destruction and some victims. At the same time, there was a strong earthquake in Osaka, Shiga, Gifu, and Nagano prefectures. A tsunami flooded the coastal locality, and some people died. The coast of Osaka and primarily Osaka Bay suffered especially heavily from the tsunami. The tsunami was also observed on the coast of Hyuga-Nada.^[13]