Monitoring the hydrothermal system in Long Valley caldera, California

C. D. Farrar; M.L. Sorey

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USGS · 70177135

Monitoring the hydrothermal system in Long Valley caldera, California

C. D. Farrar·M.L. Sorey

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Abstract

An ongoing program to monitor the hydrothermal system in Long Valley for changes caused by volcanic or tectonic processes has produced considerable data on the water chemistry and discharge of springs and fluid temperatures and pressures in wells. Chemical and isotopic data collected under this program have greatly expanded the knowledge of chemical variability both in space and time. Although no chemical or isotopic changes in hot spring waters can be attributed directly to volcanic or tectonic processes, changes in hot spring chemistry that have been recorded probably relate to interactions between and variations in the quantity of liquid and gas discharged. Stable carbon isotope data are consistent with a carbon source either perform the mantle or from metamorphosed carbonate rocks. Continuous and periodic measurements of hot spring discharge at several sites show significant co seismic and a seismic changes since 1980.

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Source-reported bounding extent: 37.55002139332707° to 37.79784832917947° latitude; -119.00665283203124° to -118.53836059570311° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeX RIS

C. D. Farrar, M.L. Sorey. 1985. Monitoring the hydrothermal system in Long Valley caldera, California. https://pubs.usgs.gov/publication/70177135

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