One lesser-known thing about Mono Lake is that its tufa towers can act almost like a record of the lake’s changing water level. The formations grow underwater where freshwater springs bubble up through the lake bottom, but once the lake drops, the exposed portions stop growing. As a result, the shoreline is scattered with tufa formations from different periods, almost like a geological timeline showing where Mono Lake has been in the past.
Even more surprising, some of the submerged springs can still be seen as clear, bubbling patches of freshwater rising through the intensely salty lake. Those tiny springs are part of the process that creates the tufa in the first place. So when you look at the strange limestone towers around Mono Lake, you’re essentially looking at the frozen remnants of an interaction between two very different waters—fresh groundwater and ancient, alkaline lake water.