Posts

Showing posts from June, 2016

Montlake - Lake on the Mountain

Image
Located in Hamilton County, Tennessee, near Chattanooga, this is one of the most interesting natural lakes, of which Tennessee has few. Montlake is a small lake near the rim of the Cumberland Plateau in Hamilton County, Tennessee. It sits close to the escarpment and has several striking features including sheer sandstone cliffs flanking most of the perimeter of the lake, as well as distinct sandstone joints zig-zagging southeast of the lake. The sinkhole itself trends south by southeast with another drainage heading southwest before turning 90 degrees and going northwest parallel to the cliff face. The lake is just over 3 acres at base height. Its depth is rumored to exceed 100' at its deepest location, but I cannot independently confirm this. Initial investigation of this feature by myself, and early Tennessee geologists suggest that Montlake is a sinkhole. It's round shape and closed elevation contours certainly makes it appear so, but that it sits on the Cumb

Don't Drink Cave Water

Image
It's becoming an almost daily routine that I feel obligated to share with people that they shouldn't drink cave water. This is me being lazy, so that I can simply point people to this essay in the future. What do I mean by cave water? Why shouldn't I drink water from a cave? Recharge to karst aquifers bypasses the filtering capability of soil through macropores and swallow holes. Water can be filtered through soils. However in many parts of karst regions there is little to no soil is present between the surface, and subsurface stream. Groundwater flows through conduits so that there is little opportunity for filtration or sorption of contaminants onto aquifer material. When water is able to flow through the grains of bedrock, the bedrock is able to filter and remove contaminants. In karst, the grains of the bedrock are dissolved and larger and larger conduits are created. Conduits, like caves, provide little, if any filtration of contaminants.