What are Ribbon lakes?
A ribbon lake is a long and narrow lake, usually found in a glacial trough. This type of lake forms when a glacier moves over an area containing alternate bands of hard and soft bedrock. The sharp-edged boulders that are picked up by the glacier and carried at the bottom of the glacier erode the softer rock more quickly by abrasion, thus creating a hollow called a rock basin. On either side of the rock basin, the more resistant rock is eroded less and these outcrops of harder rock are known as rock bars, which act as dams between which rainwater may accumulate after the retreat of the ice age, filling up the rock basin and creating a ribbon lake.
What are Marl lakes?
A marl lake is rich in the material calcium carbonate. Over time, algae and other aquatic organisms in the lake produce this insoluble material. The insolubility of calcium carbonate causes it to accumulate at the bottom of the lake. Marl is a material that is created when calcium carbonate and clay are mixed at the lakebed. Its color is beige or whitish-brown. Marl dramatically affects the color of the lake. If there is marl present in the lake, sunlight will reflect off of the lighter-colored lakebed and will cause the lake to look teal/turquoise. Many glacial and kettle lakes that have a high presence of marl can be classified as marl lakes.
Logging Requirements:
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Is Summit Lake considered to be a ribbon lake? Explain your reasoning.
1a. Are there any retreating glaciers visible around you that could have advanced and created/carved out this lake?
1b. Ribbon lakes usually have glacial debris around the sides of the lake. Does Summit Lake have this? If so, estimate the size of the debris?
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Is Summit Lake considered to be a marl lake?
2a. What color is the lake? (Higher marl concentrations in lakes yield brighter colors)
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Sources:
https://en.wikipedia.org/wiki/Ribbon_lake
http://culturalecology.info/wetland_combi/Marllakes.html
https://en.wikipedia.org/wiki/Marl
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