Upon completing the west half of the Sunset Trail, we enjoyed some nice gulps of water from one of the many natural springs that percolate their way through the town. When I think of hot springs, I know I tend to think of geysers and volcanic heated water. That’s now how it works at Hot Springs National Park. There’s just the right balance of rock types and fractures within those rocks for the water to travel to great depths within the Earth. This heats the water up before it is then forced to the surface. The water tends to reach the surface at 143 degrees Fahrenheit.

In the time it took the water to first begin its descent into the Earth and to resurface, more than 4,000 years have passed! The water will have travelled 2,000 to 8,000 feet below the surface. This descent is thanks to the porous Bigfork Chert and Arkansas Novaculite. Novaculite is a sedimentary rock. It’s typically white, gray, or black. Novaculite is made mostly of silica. It also goes by Arkansas Stone. Chert is another type of sedimentary rock made primarily of silica, but it also contains microcrystalline quartz. It’s a hard, yet brittle rock. Bigfork Chert can be found in the Ouachita Mountains of Arkansas and Oklahoma.