A detailed analysis of sediments from the island of Bonaire in the Caribbean presents convincing evidence for an extraordinary wave impact dating back some 3,300 years, even though no historical records of tsunamis exist for this island. Of particular interest are the consequences this large wave impact had on the island's ecosystem. The sediments studied by the scientists suggested that this tsunami entirely changed the coastal ecosystem and sedimentation patterns in the area. The work by Dr. Max Engel and colleagues, from the University of Köln in Germany, is published online in Springer's journal, Naturwissenschaften – The Science of Nature.
The Caribbean region is highly vulnerable to coastal hazards, including tropical cyclones, earthquakes, volcanoes, and tsunamis. Even though the island of Bonaire has not experienced a tsunami during the past 500 years, which is the period of historical documentation, overwash deposits from a coastal lagoon provide evidence for at least one such event in prehistory.
Engel and colleagues investigated sediment cores from Washington-Slagbaai National Park. They looked specifically at grain size distribution, carbonate content, organic matter, magnetic susceptibility and fauna. Their analyses showed that the sediments had criteria typically linked with tsunami deposits, consistent with a tsunami with a maximum age of 3,300 years.
The authors conclude: "This single catastrophic event is of long-term ecological significance. Formation of a barrier of coral rubble was triggered by the tsunami separating a former inland bay from the open sea and turning it into a highly saline lagoon which persists until today. Further studies of the geology of tsunamis, using well-dated deposits, are required over the entire Caribbean to reconstruct reliable patterns of magnitude, frequency and spatial occurrence of tsunami events and their environmental impact."
Engel M et al (2012). A prehistoric tsunami induced long-lasting ecosystem changes on a semi-arid tropical island - the case of Boka Bartol (Bonaire, Leeward Antilles). Naturwissenschaften – The Science of Nature; DOI 10.1007/s00114-012-0993-2
This press release was posted to serve as a topic for discussion. Please comment below. We try our best to only post press releases that are associated with peer reviewed scientific literature. Critical discussions of the research are appreciated. If you need help finding a link to the original article, please contact us on twitter or via e-mail.
Bardarbunga, a subglacial stratovolcano, showing increased seismic activity; 2010 eruption caused air travel chaos
A coffee entrepreneur claims his brew is different — and better — than the trendy civet poop coffee. And it starts with the idea that elephants, unlike humans or civets, are herbivores.
Structural colours are more visible and vivid than those that use pigments as many examples from the natural world demonstrate. But sometimes pure white is what is required
Dutch biologist Ingrid van der Meer often meets with disbelief when she talks about her work on dandelions and how it could secure the future of road transport.
Pretend for a minute that it’s 1875 and you’re a mining engineer whose job it is to figure out how much gold is in them thar hills. Get it wrong, and your company is going to waste a lot of time and money hunting for gold that’s not there—or worse yet, miss out on the mother lode
It can only switch from black to transparent and back again, but that's a start
What happens when you add folds to materials that are only a few atoms thick? Several scientists set out to find the answer — and discovered that these nano-wrinkles can be quite useful.
A battery tattoo powered by perspiration has been unveiled by chemists in California.
Huge earthquakes could be on the way to Chile, after the major quake in April this year failed to relieve seismic stresses that have built up for 150 years
The Swedish government is looking at building a nuclear reactor purely for research, although a decision will not be taken until after a general election in September, Swedish daily Dagens Industri reported.