To the south of the Polar Front, near the Antarctic Peninsula, a group of researchers discovered microfossils of microorganisms known as forams, or “foraminifera.” These were previously unknown in this region, though foraminifera play a fundamental role in the food chain in all oceans. The study was published in the journal “Progress in Oceanography.”
Andrea Navarro, IDEAL Center: The Drake Passage is a strait approximately 800 kilometers wide that separates the South American continent from Antarctica. The Antarctic Circumpolar Current flows through this area, connecting the main ocean basins of the planet. This is a challenging region for conducting scientific research due to strong winds and frequent storms. As a result, there are very few geological records of this area. The last studies of large geographical scale took place in the 1960s.
However, between February and April 2016, a team of German and Chilean scientists took part in the “Paleodrake” expedition aboard the German icebreaker Polarstern, belonging to the Alfred Wegener Institute (AWI). In that campaign, sediments samples were taken from the Chilean continental margin, between the Drake Passage and the Bransfield Strait, between the South Shetland Islands and the Antarctic Peninsula.
“We wanted to see if the surface sediments really reflected the current oceanic biogeographic regions and the physical, chemical, and biological properties of the three ocean fronts: the South Antarctic, polar, and southern fronts of the Antarctic Circumpolar Current,” explained paleoceanographer Dr. Carina Lange. Dr Lange is a researcher from the Research Center – Dynamics of High Latitude Marine Ecosystems (IDEAL) at the Austral University of Chile (UACh) and faculty member at the University of Concepción (UdeC).
After analyzing the surface sediments, the research team created a scientific study that was published in a special IDEAL Center volume in the scientific journal, “Progress in Oceanography.”
Marine Biologist Paola Cárdenas directed this research effort. One of the principal results included a discovery near the Antarctic Peninsula of Foraminifera, tiny organisms that are invisible to the naked eye. Their skeletons are made up of calcium carbonate. These are fundamental in the food chains in all the oceans of the planet. Microfossils of these organisms can be used as bio-indicators of past ocean productivity, sea surface temperature, and — in conjunction with other microfossils and geochemical parameters– they can provide information on salinity changes.
Dr. Carina Lange, a researcher from the IDEAL Center, took part in the discovery of the microfossils of foraminifera. These were previously unknown in this region, and their role is fundamental in the food chain in all of the oceans.
“South of the Polar Front, we found foraminifera fossils in a perfect state of preservation, despite the passage of hundreds of years. This is something which had not been seen in previous expeditions. From a scientific point of view, this is astonishing,” explained Dr. Lange.
Researcher Lange indicated that this discovery is not related to the effects of climate change, but instead reflects the technological progress that has been made in the drilling equipment. Unlike the conditions of the 1960s, it is now possible to extract the topmost superficial layer of the sediments of the oceans
The information obtained by these scientists will be very important in the future calibration of biological and geochemical indicators in this under-explored and difficult-to-access area.