That's a 50' waterfall of crimson primordial ooze
.Roughly 2 million years ago, the Taylor Glacier sealed beneath it a small body of water which contained an ancient community of microbes. Trapped below a thick layer of ice, they have remained there ever since, isolated inside a natural time capsule. Evolving independently of the rest of the living world, these microbes exist without heat, light, or oxygen, and are essentially the definition of "primordial ooze." The trapped lake has very high salinity and is rich in iron, which gives the waterfall its red color. A fissure in the glacier allows the subglacial lake to flow out, forming the falls without contaminating the ecosystem within.
If you're planning an expedition to investigate the ooze, don't forget to pack lots of Cthulhu snacks
. Dealing with all those Shoggoths and the Mi-go is tough work.