Crystal Geyser: An Unusual Cold Spring System, Grand County

Abstract

Crystal Geyser is a cold carbon dioxide (CO2) geyser, part of a natural spring system along the Little Grand Wash fault south of Green River, Utah (figure 1). The spring system hosts a series of CO2-driven geysers and springs with active and fossil microbial mats and tufa deposits composed of carbonate and iron oxide and iron oxyhydroxide minerals (Potter-McIntyre and others, 2017; Knuth and Potter-McIntyre, 2018) (figure 2). Additionally, progressively older carbonate spring deposits crop out on some of the topographic highs in the area because these relatively erosion-resistant deposits armor the paleo-land surface and slow down erosion (Shipton and others, 2004; Burnside, 2010). Recent radiometric U-Th dating of carbonate terraces and embedded veins reveal that CO2-charged fluid has constantly leaked to the surface for over 400 thousand years during the Pleistocene (Burnside, 2010). Crystal Geyser is a popular place for tourists, and it is not uncommon to see children playing in the spring.