Tufa is the name for an unusual geological formation.
Tufa is a rough, thick, rock-like calcium carbonate deposit that forms by precipitation from bodies of water with a high dissolved calcium content. Tufa deposition occurs in five known ways:
- Mechanical precipitation by wave action against the shore. This form of tufa can be useful for identifying the shoreline of extinct lakes, especially in the Lake Lahontan region.
- Precipitation from supersaturated hot spring water entering cooler lake water
- Precipitation in lake bottom sediments which are fed by hot springs from below
- Precipitation throughout the lake as the lake dries out
- Through the agency of algae
