Soda Dam is a travertine deposit within the Jemez Caldera. Travertine is finely crystalline limestone formed by the precipitation of calcium carbonate from water. It is a common deposit at hot springs. All photos by Geoffrey Johnson. Thanks to Zoe Johnson.
At Jemez, a hydrothermal system feeds water up to surface along a fault. The deposits are as old as 1 million years. The youngest deposit is about 5,000 years old and is about 100 m long.
Old attachment point on cliff for soda dam. A roadcut breached the dam in the 1950s.
Soda Dam hot spring.
Soda Dam hot spring.
Obsidian cliff at Jemez. Photo by Geoffrey Johnson.
Redondo Peak in Valles Caldera. Redondo Peak is a resurgent block or dome. It is the second highest (at 3,431 m) point in the Jemez Mountains and rises 840 m above the caldera floor. Redondo Peak is made of Bandelier tuff and it is cut by faults. Photo by Geoffrey Johnson.
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