The 15th photo of the week is of an area of natural acid rock drainage (ARD) in Eagle Plains, Yukon. ARD is a phenomenon that most people associate with mine tailings and mine waste. However, it occurs naturally as well since the only criteria that need to be met are a source of oxidized water, such as rain, rocks or minerals that have a high sulphur content, and a very little carbonate in the rocks. Once you have these three things ARD is very possible, and it occurs naturally all over the world. As you can see at this site the ARD is pretty much killing everything in its path. This is no surprise since the water in the area is about pH 1 or 2 and most things cannot survive such a hostile environment.
That said, a lot of research is going into looking at what an survive in such hostile places and how this might relate to extra-terrestrial life.
Thanks for reading!