A commonly held theory of the origin of epithermal ore deposits relates Au, Ag, Hg, As, Sb, Tl, and other "volatile" elements to "fossil" hot-spring systems that transported and deposited these metallic elements close to the ground surface existing at the time. In the early 1970's, an emission-spectrographic method using short-wavelength radiation (SWR) was developed for use in the analysis of these "volatile" elements. This method was applied to 125 samples of rock and hot-spring chemical precipitates from Yellowstone National Park and 43 samples from Steamboat Springs, Nev. The results of those analyses are presented here. Recently, other, more sensitive methods for the analyses of gold and volatile elements have been developed and (or) become less expensive, but these methods generally have not yet been applied to Yellowstone samples. -- First paragraph.

A commonly held theory of the origin of epithermal ore deposits relates Au, Ag, Hg, As, Sb, Tl, and other "volatile" elements to "fossil" hot-spring systems that transported and deposited these metallic elements close to the ground surface existing at the time. In the early 1970's, an emission-spectrographic method using short-wavelength radiation (SWR) was developed for use in the analysis of these "volatile" elements. This method was applied to 125 samples of rock and hot-spring chemical precipitates from Yellowstone National Park and 43 samples from Steamboat Springs, Nev. The results of those analyses are presented here. Recently, other, more sensitive methods for the analyses of gold and volatile elements have been developed and (or) become less expensive, but these methods generally have not yet been applied to Yellowstone samples. -- First paragraph.

"Home to more than 10,000 thermal features, Yellowstone has experienced over 20 large hydrothermal explosions producing craters from 100 to over 2500 meters in diameter during the past 16,000 years. Using new mapping, sampling, and analysis techniques, this volume documents a broad spectrum of ages and geologic settings for these events and considers additional processes and alternative triggering mechanisms that have not been explored in previous studies. Although large hydrothermal explosions are rare on the human time scale, the potential for future explosions in Yellowstone is not insignificant, and events large enough to create a 100-m-wide crater might be expected every 200 years. This work presents information useful for determining the timing, distribution, and possible causes of these events in Yellowstone, which will aid in the planning of monitoring strategies and the anticipation of hydrothermal explosions."--Publisher's description.