According to a new study, a series of burial sites on Pacific islands and northern Scotland were likely related to catastrophic tsunamis. The research was published July 13, 2018, in the Journal of Archaeological Method and Theory.
Tsunamis have never been considered as explanations for burial sites before – which is why no prehistoric coastal mass graves have ever been identified in the archaeological record as tsunami-related.
The researchers looked at coastal mass burial sites in the Solomon Islands and Vanuatu in the Pacific, as well as the Scottish islands Orkney and Shetland in the Atlantic. The mass graves cover a long timeframe of human history – from about 5,000 years ago to as recent as about 500-600 years ago. Goff said:
We already know that tsunamis have occurred in all the areas that we explored in this study, and the ages for mass burials match those of the geological evidence for past events.
Looking at the evidence from the burial sites considering the potential of tsunamis, we were able to make a strong case for many of these sites being related to major tsunamis, as opposed to more standard explanations like warfare or an epidemic.
For example, at the site in the Solomon Islands, the method of burial and the age of the people buried is consistent with what we’d expect after a tsunami – people were buried in atypical positions, and they’re uncharacteristically young.
Mass graves with up to 60,000 bodies suggest that the need to bury the dead after the event can overwhelm the normal funerary protocols. Goff said:
Our archaeological research in conjunction with geological evidence recognises that exactly what has happened in modern events must have happened in the past.
The researchers’ argument is not that every mass burial is tsunami-related, but that in a coastal context in particular, there is the danger of not considering it and, as such, misinterpreting much about human-environment interactions in prehistory.
There is a fairly simple way forward here. When people die in a tsunami, they inhale saltwater that contains small marine micro-organisms called diatoms, which means they suffocate and then drown.
These diatoms travel through the blood stream and are deposited and preserved within the bone marrow of larger bones. If we can find marine diatoms, this may indicate that the body is a tsunami victim.
Goff says the research provides new insights into past human-environment interactions and a new perspective on past catastrophic events. He said:
Proving that a site is related to a past tsunami could lead to a fundamental rewrite of how we interpret coastal human settlement in prehistory, and change what we thought we knew about the culture and people living in the region at the time. It could also have dramatic implications for how archaeologists analyze a site.
Bottom line: A new study suggests that some mass burial sites in the Pacific, Mediterranean and northern Scotland were likely related to catastrophic tsunamis.
Eleanor Imster has helped write and edit EarthSky since 1995. She was an integral part of the award-winning EarthSky radio series almost since it began until it ended in 2013. Today, as Lead Editor at EarthSky.org, she helps present the science and nature stories and photos you enjoy. She also serves as one of the voices of EarthSky on social media platforms including Facebook, Twitter and G+. She and her husband live in Tennessee and have two grown sons.