A marine biologist claims to have discovered a huge underwater sinkhole—or blue hole—in the Great Barrier Reef.
Blue holes are large marine sinkholes that mostly formed during past ice ages when sea levels were far lower—this mean they were subject to the same erosion from rain and chemical weathering as any other area. After being submerged, the erosion ceased, and the deep blue caverns were left.
Johnny Gaskell noticed the lagoon using Google and decided to explore the region more closely. On visiting the site, he found a thriving ecosystem, which he described in an Instagram post.
“After spotting this deep blue hole on google maps we decided to head far offshore, out further than our normal Reef trips to see what dwelled within,” he wrote. “At around 15-20m [50-65ft] deep there was huge Birdsnest Corals (Seriatopora) and super elongated Staghorn Corals (Acropora) both of which were among the biggest and most delicate colonies I’ve …