THE ORIGINS OF THE GREAT BARRIER REEF
The great Barrier Reef began to form where the shallow area of the sea floor
had favorable conditions to encourage and support colonization of benthic
plants and animals. These conditions are the presence of a hard bottom
free from excess mud and sand. The area must be clear, warm sea water
with enough movement to circulate oxygen and plankton to the colonial organisms.
The skeletal limestone remains of corals and other are then cemented together
by calcareous algae. The process continues as the reef "grows" towards
the surface. Particular to the Great Barrier that encouraged the
continued growth of the reef is the large continental shelf off the coast
of Queensland which provided the base for the reef system. A second
factor was the fluctuating sea levels that occurred in the Pleistocene
era. A time when the continental shelf was exposed to the air.
At this time the colonial organism were able to keep pace with the raising
sea level until the present reefs were formed. Warm waters and favorable
oceanic and tidally induced currents maintain flourishing coral growths
throughout the Great Barrier Reef at the present time. The Great
barrier system is a cluster of shelf reefs which are found in shallow waters
as opposed to oceanic reefs which are found in deeper waters.