Changes in the discharge characteristics of thermal springs and fumaroles in the Long Valley Caldera, California, resulting from earthquakes on May 25-27, 1980

Changes in flow rate and turbidity have been observed and measured in hot springs in the Long Valley caldera, California, following earthquakes with magnitudes up to 6.3 in May 1980. Increases in flow rate of some hot springs occurred within minutes of the earthquakes, followed by more gradual decreases in flow rate to pre-earthquake levels. Spring temperatures and chemistries also show no long-term variations following earthquakes. Transient changes in discharge characteristics of the hot springs appear to result from increases in the permeability of fault conduits transmitting the hot water to the surface. (USGS)