Ilaria Rosella Pagliaro About 40 mysterious circular formations discovered on the bottom of Lake Michigan: NOAA scientists hypothesize that they are sinkholes similar to those in Lake Huron
©NOAA
The Great Lakes Environmental Research Laboratory of the NOAA recently confirmed that there are indeed about 40 rounded shapes on the Lake Michigan bottom. First spotted in 2022, the natural geological features have remained the center of fascination among many researchers.
NOA analysts discovered these strange circular pits using the sonar technology in 2022. The diameter of these structures ranges from around 500 feet up to approximately 1,015 feet. They are distributed within a range of 300-600 feet in depth. This spotting reported by the wreck hunter who detected similar structures with such instruments on board also correlates with the latest detection. A research group has finally been able to study them in August 2023.
According to shipwreck hunter Brendon Baillod, the shape structure stretches over about 14 miles due east, cutting from Sheboygan to Port Washington.
Sinkholes and geological formation of sinkholes
These are probably “sinkholes“, a natural process often seen in karst areas, where moving water gradually dissolves the soil. According to the U.S. Geological Survey, the areas which tend to be at risk for forming sinkholes include those made from soluble rocks, such as limestone, gypsum, or salt, all of which exist in Lake Michigan’s subsurface. Lake Michigan is composed largely of limestone, which provides a reason for these depressions.
Similar phenomena have been seen in nearby Lake Huron, where sinkholes harbor an exotic microbial community that gives pointers to conditions that may have existed on Earth 2.5 billion years ago. In these oxygen-starved and sulfur-rich areas, microbial life thrives, forming striking purple mats dominated by strains of photosynthetic cyanobacteria such as Phormidium autumnale.
Such microorganisms are able to convert the sun’s energy into organic carbon, and their bacterial relatives exist in other extreme environments, including frozen lakes in Antarctica and hot springs in Yellowstone National Park. In addition, sinkholes in Lake Huron also host methane-producing Archaea and numerous different eukaryotes, several of which have not yet been classified.
The scientists of the NOAA speculate that this might be so because the sinkholes in Lake Michigan contain similar life forms as found in Lake Huron; more research is called for. It will only be through such explorations that will establish whether or not such formations contain similar microbial life, and also get to know or deepen our understanding of what the environmental condition was during ancient Earth times.
Source: US Geological Survey – NOAA
