Gas and Isotope Chemistry of Thermal Features in Yellowstone National Park, Wyoming

ABSTRACT

This report presents 167 gas analyses and 59 related water analyses on samples collected from thermal features at Yellowstone between 2003 and 2012. An overview of previous studies of gas emissions at Yellowstone is also given. The analytical results from the present study include bulk chemistry of gases and waters and isotope values for water and steam (δ¹⁸O, δD), carbon dioxide (δ¹³C only), methane (δ¹³C only), helium, neon, and argon. We include appendixes containing photos of sample sites, geographic information system (GIS) files including shape and kml formats, and analytical results in spreadsheets. In addition, we provide a lengthy discussion of previous work on gas chemistry at Yellowstone and a general discussion of the implications of our results. We demonstrate that gases collected from different thermal areas often have distinct chemical signatures, and that differences across the thermal areas are not a simple function of surface temperatures or the type of feature. Instead, gas chemistry and isotopic composition are linked to subsurface lithologies and varying contributions from magmatic, crustal, and meteoric sources.

Revised October 27, 2014

First posted May 12, 2011