Definition: A natural chemical precipitate of carbonate minerals; typically aragonite, but often recrystallized to or primarily calcite; which is deposited from the water of mineral springs (especially hot springs) or streams saturated with calcium carbonate.
Definition: A step-like feature between higher and lower ground: a relatively flat or gently inclined shelf of earth, backed and fronted by steep slopes or manmade detaining walls.
Definition: A habitat that is in or on a body of water containing low concentrations of dissolved salts and other total dissolved solids (<0.5 grams dissolved salts per litre).