04 Jul , 20:57
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The mysterious "Blood Falls" at Taylor Glacier in Antarctica were simultaneously captured by three types of sensors — and scientists have for the first time described the mechanics of the discharge of a one-and-a-half-million-year-old iron-rich brine. The results have been published in Antarctic Science.
Peter Doran from Louisiana State University and his colleagues analyzed data collected in September 2018, when GPS receivers, video cameras, and temperature sensors happened to be running simultaneously at the moment of one of the periodic discharges of blood-red liquid. It was found that during the discharge, the glacier's surface subsided by approximately 15 mm, and its movement speed dropped by 10%. This indicates that the brine pressure inside the ice body significantly affects the dynamics of the entire glacier.
"Blood Falls" owes its name to its intense red color: the water gets its hue from dissolved ferric iron, which oxidizes upon contact with air. The source of the brine is a subglacial lake that was cut off from the surface approximately 1.5 million years ago. Throughout this entire time, bacteria have inhabited it, completely deprived of access to sunlight and oxygen: they obtain energy through the oxidation of iron and sulfur compounds.
The periodic discharges, according to the study's authors, are determined by cycles of brine pressure buildup and release. As soon as the pressure reaches a threshold value, the liquid breaks through cracks in the glacier to the surface — and at that moment the glacier literally subsides and slows down.
The discovery is significant not only for understanding Antarctic ecosystems but also for assessing the possibility of similar life forms existing on other planets with subglacial oceans — for example, on Jupiter's moons.
