Green Lake and its sister Round Lake, are a pair of unique bodies of water located in the aboriginal territory of the Onandoga nation. This writeup will concern itself with Green Lake, but much of this information carries over to its sister.
The final remnants of a plunge pool formed during the last ice age by a glacial waterfall at least twice the size of Niagara Falls; Green Lake is situated in a gorge and fed entirely by rain and groundwater. As a result, it is one of the few meromictic lakes on earth.
So, okay, in general terms, lakes do this:
For the warmer months water organizes into distinct layers, each circulating in their own way. The warmest water, being the least dense, sits at the top. This is where the phytoplankton hang out, producing oxygen and consuming nutrients. The coldest water, being the most dense, sits at the bottom. This is where nutrients tend to accumulate and oxygen gets depleted by animal life. As summer turns to winter the top layers get colder and the water mixes as stratification breaks down, the same happens as winter turns back to summer. This process helps more evenly distribute oxygen and nutrients.
Ok so Green Lake doesn't do this.
The bottom of the lake is totally devoid of oxygen, so no decomposition; whatever falls down there, stays down there. The water is also very high in mineral content, which leaves layers of calcite deposits on anything that isn't moving. Moreover there is a layer of bacterially active water around 18-20 meters down that makes the water purple at that specific depth. Thanks to photosynthetic bacteria that deposit some of the minerals in the water, Green Lake is home to one of the few existing freshwater reefs.
I just think its neat.
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its real bad