Geology of the Cays
The Commonwealth of The Bahamas is a group of some 700 Islands and nearly 2,500 small islets or cays resting on an immense plateau of tertiary limestone that was formed between 1 and 2 million years ago. The Exumas are centrally located resting between the shallow banks and Exuma Sound a mile deep canyon created by the action of the sea over the past million years.
During glaciation some 70,000 to 10,000 years ago, water was taken from the oceans to form the ice at high latitudes, thus global sea level dropped by as much as 120 meters, exposing the continental shelves and the Bahamas plateau. During deglaciation, the melted ice-water returned to the oceans, causing sea levels to rise. These changes in sea level account for the formation by dripping water of both stalactites and stalagmites in limestone caves (Rocky Dundas) and other caves now found below sea level in the Bahamas.
The Bahamas are not volcanic like many of the Caribbean and Pacific islands. Limestone is the only rock found in the Bahamas and is frequently worn razor sharp by the action of the wind and sea. Much of what you see underwater and along the shore today is the result of coral growth on the plateau of limestone.
There are no fresh water rivers in the Bahamas as water erodes limestone and the cays contain numerous sink holes and caves. A few fresh water wells can be found on the cays. Creeks, such as those found on Shroud Cay and Warderwick Wells are created by the tidal flows of salt water. As a result, the soil on the cays is extremely thin and the limited amount of fresh water creates a harsh environment for both plant and animal life.
The growth of coral reefs on the limestone plateau accounts for the beautiful clear waters of the Bahamas. Wave action over the centuries has created the amazing white beaches consisting of tiny fragments of coral, sea shells and limestone. The seas in the Bahamas are very fertile and a wide variety of sea life exists deep in Exuma Sound, along the coral reefs and on the banks. In addition, numerous tropical birds have made the Bahamas their home.
Enjoy your visit to Exuma Park!