The Soda Dam was formed by calcium carbonate and travertine deposits from the thermal spring water that was built up over the course of 7,000 years. The river flows through the dome-like bridge created by the deposition of these minerals across the river. There is also a waterfall at the site, over 300 feet long, 50 feet high, and 50 feet wide at the base. The hot spring water is heated by volcanic magma of the
Valles Caldera. The water percolates through shale and limestone, following cracks in the Jemez geological fault zone to emerge at the springs. Because algal filaments are contained within the carbonate rock, the site is used to study ways in which possible ancient life on Mars may be detected through examination of rocks. The hot spring water emerges from several sources and seeps. ==History==