Remember Freshwater Marl
Freshwater Marl Technical Terms
Freshwater Marl: A soft, grayish to white, earthy or powdery, usually impure calcium carbonate precipitated on the bottoms of present-day freshwater lakes and ponds largely through the chemical action of algal mats and organic detritus, or forming deposits that underlie marshes, swamps, and bogs that occupy the sites of former (glacial) lakes. The calcium carbonate may range from 90% to less than 30%. Freshwater marl is usually gray; it has been used as a fertilizer for acid soils deficient in lime. Syn.: bog lime. Compare – marl, coastal marl. SW