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Geochemistry and Soils of the Big Smoky Valley Fens, Nevada

Sade K. Cromratie Clemons·Geoffrey John Moret·Katherine J. Earp
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Abstract

Fens are groundwater-fed wetlands that can provide habitat for plants and animals. Due to anthropogenic activities and climate change, many fens around the world are at risk. This paper presents the results of a study of the hydrology and geochemistry of fens in Big Smoky Valley, central Nevada to support the Bureau of Land Management’s activities in the area. A water sample from the largest fen in the study area was analyzed for its water chemistry and compared to a nearby alluvial aquifer and hot spring. The high SiO 2 concentration of the fen sample implies that the fen water may originate from geothermal water. A soil core was taken to analyze radiocarbon age and soil type. A majority of the core was composed of silt and clay interlayered with water-filled voids. Changes in the character of the clay with depth suggest that there may have been changes in the depositional environment over time. Radiocarbon dating of Ruppia seeds showed longevity of the fen, with the minimum 14 C age of the core as 4,375±40 years. This paper provides reconnaissance-level information on the Big Smoky Valley fens, but further information would be needed to better understand the source of water to the fens or how the fen environment has changed over time with climate.

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Journal of the Nevada Water Resources AssociationArticle

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Sade K. Cromratie Clemons, Geoffrey John Moret, Katherine J. Earp. 2025-12-01. Geochemistry and Soils of the Big Smoky Valley Fens, Nevada. https://doi.org/10.22542/jnwra/2025/1/2

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Article subjectBig Smoky Valley placeJournal of the Nevada Water Resources Association subjectNevada placeUnited STates place

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