A series of enigmatic submarine mounds hidden beneath the western Ross Sea is moving from field exploration to intensive scientific analysis, as researchers begin examining the vast dataset collected during the MYSTERO Antarctic expedition earlier this year.
The project, led by Italian partners including OGS, CNR-ISMAR, CNR-ISP, the Stazione Zoologica Anton Dohrn and the University of Naples Federico II, is investigating hundreds of circular seafloor features found between roughly 300 and 1,200 metres water depth. Their origin remains uncertain, making them one of the Ross Sea's most intriguing geological puzzles. Early hypotheses range from fluid or gas-related processes to the interaction of oceanographic and sedimentary forces over long timescales.
The January-February 2026 field campaign aboard the icebreaker Laura Bassi gathered an extensive suite of observations, including multibeam bathymetry, seismic data, sediment samples and water-column measurements. According to a 2026 conference abstract, the team mapped more than 2,000 square kilometres of seafloor during the expedition.
Researchers are now focusing on analysing those data, with OGS recently advertising scholarships dedicated to the marine geophysical datasets generated by the project. The effort highlights the transition from discovery to interpretation, where the most significant scientific insights may emerge.
The mounds could prove important for several branches of Antarctic research. Sediments associated with these features may preserve valuable records of past ocean and climate conditions, offering clues to the evolution of the Antarctic Ice Sheet and Ross Sea circulation patterns. Researchers are also examining whether interactions between deep water masses and the mounds influence local seabed environments.
Another intriguing possibility is ecological. Preliminary observations reported in conference material identified corals, bryozoans, sponges and other benthic organisms living on some mound tops, suggesting these structures may provide habitat in the deep Ross Sea. However, this interpretation remains preliminary and has not yet been confirmed through peer-reviewed publication.
A second expedition planned for the 2026/27 Antarctic season is expected to deploy an ROV from the Stazione Zoologica Anton Dohrn, potentially delivering the first close-up imagery of these mysterious undersea landscapes.