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.
Sheets of programmable matter can be made to pop into complex 3D shapes 100 times taller than their original thickness when heated, and could find uses in medicine
A particle physics student has used his downtime to build a Lego model of the world's most powerful particle accelerator, the Large Hadron Collider (LHC), and is now lobbying the toy company to take it to market.
Get the full the story behind a $761 jar of peanut butter and other exorbitantly priced everyday objects used by scientists
Satellite imagery shows 20 new craters around holes discovered last year in Siberia
Young maths whizz from Iran uses simple equations to paint stunning images that bizarrely look like marine objects, and makes a fractal Africa
A new breed of the hyper-accurate clocks could help scientists detect the elusive ripples in space-time faster and cheaper
Replacing the spark plugs in engines with lasers could lead to more complete fuel combustion and greener cars
After a two-year hiatus, the Large Hadron Collider will restart soon, twice as strong and with some "dark" mysteries to unlock
Global antibiotic resistance is imperilling our existence. We need clever ways to find new bug-beating drugs
If dark matter turns out to interact with photons, its glow would be visible at the edges of spiral galaxies – now we just have to find it