Hydrologic data for Long Valley Caldera, Mono County, California, 1987-93

Hydrologic data were collected during 1987-93 as part of the U.S. Geological Survey's long-term Volcanic Hazards Monitoring Program of the Long Valley Caldera, Mono County, California. The data are presented in graphs or tables. Data collected for the Long Valley Hydrologic Advisory Committee monitoring program also are presented. Hydrologic data collected include continuous record of ground-water levels in 6 wells, instantaneous measurement of ground-water levels in 55 wells, continuous record of discharge at 2 streams and 5 springs, instantaneous discharge measurements at 4 streams and 2 springs, ground-water temperature profiles of 3 thermal wells, continuous record of water temperature in 1 stream and 5 springs, vent gas temperatures at 2 fumaroles, and chemical and isotopic analyses of water samples collected at 13 ground-water and 6 surface-water sites. Precipitation amounts at three sites also are included.