A stunning underwater ecosystem was captured in the Antarctic.

An iceberg the size of Chicago, named A-84, broke away from the George VI Ice Shelf on January 13. The George VI Ice Shelf is one of the massive floating glaciers attached to the Antarctic Peninsula ice sheet.

An international team aboard Schmidt Ocean Institute's R/V Falkor, working in the Bellingshausen Sea, decided to investigate the newly exposed area that had been covered by ice until then.

The team reached the seafloor on January 25, becoming the first to explore a location that had never before been accessible to humans.

The ice that calved was approximately 510 square kilometres (209 square miles), revealing an equivalent area of seafloor.

Expedition co-chief scientist Dr. Patricia Esquete from the Centre for Environmental and Marine Studies (CESAM) and the Department of Biology (DBio) at the University of Aveiro, Portugal, said: 'We seized upon the moment, changed our expedition plan, and went for it so we could look at what was happening in the depths below.

'We didn't expect to find such a beautiful, thriving ecosystem. Based on the size of the animals, the communities we observed have been there for decades, maybe even hundreds of years.'

Using Schmidt Ocean Institute's remotely operated vehicle, ROV SuBastian, the team spent eight days observing the deep seafloor, discovering flourishing ecosystems at depths of up to 1,300 metres.

Footage captured large corals and sponges supporting diverse animal life, including icefish, giant sea spiders, and octopuses.

The team was stunned by the significant biomass and biodiversity of the ecosystems, and they suspect they may have discovered several new species.

Expedition co-chief scientist Sasha Montelli of University College London (UCL) said: 'The ice loss from the Antarctic Ice Sheet is a major contributor to sea level rise worldwide.'

In addition to collecting samples, the team deployed gliders to study the impacts of glacial meltwater. Preliminary data suggests high biological productivity and a strong meltwater flow from the George IV Ice Shelf.

The expedition was part of Challenger 150, a global collaboration focused on deep-sea research.