The interesting underwater geological structures in the Great Barrier Reef are found to be exceptionally massive than previously thought, according to researchers.
The Great Barrier Reef was known to exist in Australia since the 1970s, but its shape and size were relatively unknown until now. With the help of the Royal Australian Navy, the scientists uncovered another massive reef with donut-shaped mounds just behind the Great Barrier Reef.
Researchers from James Cook University, Queensland University of Technology and University of Sydney used the data provided by the Navy's LiDAR-equipped aircraft to discover the 33-foot-deep and 600- to 1,000-foot-wide reef. The LiDAR is a technologically advanced radar that uses laser in the place of radio waves.
The circular mounds are actually bioherms, or carbonate rock formations, of Halimeda, a type of green algae that calcify upon death to form limestone flakes and accumulate over the years. The massive reef is found to cover about 6,095 square kilometers (2,353 square miles), which is three times larger than the estimated size.
Robin Beaman, a marine geologist at James Cook University, said that while the Great Barrier Reef was discovered sometime between 1970 and 1980, the scale, shape and size of the reef weren't understood in detail. He added that it was amazing to know that the reef was much deeper than previously estimated.
Mardi McNeil, the study's lead author and a researcher at the Queensland University of Technology, said that the reef area they were able to map extends from the Torres Strait to north of Port Douglas. He added that the massive reef covers an area larger than the coral reef present in the northern part of the Great Barrier Reef.
The discovery of the bioherms is significant because it could help the researchers to study the environmental conditions of the seafloor in the past 10,000 years. The impact of acidification and increase in the temperature of ocean water on sensitive organisms like Halimeda is also a promising scope for research.
"We did not know their shape, nor the enormity of their size," said Beaman. "What we found deep behind the Great Barrier Reef has amazed us. It's the deeper part of the seafloor, the inter-reef and the strange shape of the geological structure that has grabbed us. These are vast meadows of green algae covering the inter-reef seafloor, and more than 10,000 years of growth, building up into these weird-looking Halimeda bioherms."
Photo: Steve Parish | Flickr