In Victoria Land, East Antarctica, a natural phenomenon takes place. Blood Falls is a small saltwater waterfall from Taylor Glacier that is tainted with iron oxide, giving it the appearance of blood.
Blood Falls is not the melted residue of Taylor Glacier like most glacier waterfalls are. Instead, it is a plume rising from an ancient salt lake trapped beneath Taylor Glacier's 400 meters of ice. This occurred years ago when the ocean flooded East Antarctica and created a salty inland lake. Years later, glaciers formed over the saline lake, trapping the salt water. The liquid below became saltier as the surface of the glacier froze as the water was removed to form ice. Today, the water is about three times saltier than the ocean. This salt content keeps it from freezing even in freezing temperatures.
Blood Falls includes large amounts of iron. When this very salty, iron-rich water interacts with the oxygen at the surface, a process called oxidation occurs, turning the water red. A similar process occurs when metal comes into contact with oxygen (which causes rust).
Scientists have discovered many microbes in Blood Falls called extremophiles (microbes that can withstand extremely harsh conditions). The microbes in Blood Falls convert the sulfur and iron compounds present into energy. Therefore, no oxygen or light is required for them to survive.