In 1982, the United States Geological Survey under the Volcano Hazards Program began an intensive effort to monitor and study geologic unrest in Long Valley Caldera.[1] The goal is to provide residents and civil authorities with reliable information on the nature of the potential hazards posed by this unrest and timely warning of an impending volcanic eruption, should it develop.[15] Most, perhaps all, volcanic eruptions are preceded and accompanied by geophysical and geochemical changes in the volcanic system.[15] Common precursory indicators of volcanic activity include increased seismicity, ground deformation, and variations in the nature and rate of gas emissions.[15]