Evidence of the Overturn - Barbados
The Ice Age Evidence of the Overturn - Barbados
Evidence of a recent, violent past can be found in many world regions that are currently thought to be stable.
Much of Barbados is surrounded by coral reefs. The shore line in many places is the outer edge of an older coral reef that now forms a cliff. You can see that the waves cut a platform at the base of the cliff. The top of the cliff is the top surface of the old reef, that would have been level along its entire length, but this is not now the case. The top of the old reef slopes - it is not the same height above sea level from one end of the island to the other, demonstrating that this is not simply the result of rising and falling sea levels. The island has been upthrust, unevenly, up to 10m in one go.Other cliffs inland show that the process of dramatic change has been repeated at intervals throughout the geological history of the island.
Where the old reef cliff has an overhang, the surface structure of the coral is undamaged, showing that this has not been exposed to prolonged wave action as sea levels slowly rose or fell. The uplift was sudden.
A huge block of limestone sits on top of the old reef. This is evidence of a vast tsunami sweeping this shoreline at some point in the past