Changes in geyser eruption behavior and remotely triggered seismicity in Yellowstone National Park produced by the 2002 M 7.9 Denali fault earthquake, Alaska

Abstract

Following the 2002 M 7.9 Denali fault earthquake, clear changes in geyser activity and a series of local earthquake swarms were observed in the Yellowstone National Park area, despite the large distance of 3100 km from the epicenter. Several geysers altered their eruption frequency within hours after the arrival of large-amplitude surface waves from the Denali fault earthquake. In addition, earthquake swarms occurred close to major geyser basins. These swarms were unusual compared to past seismicity in that they occurred simultaneously at different geyser basins. We interpret these observations as being induced by dynamic stresses associated with the arrival of large-amplitude surface waves. We suggest that in a hydrothermal system dynamic stresses can locally alter permeability by unclogging existing fractures, thereby changing geyser activity. Furthermore, we suggest that earthquakes were triggered by the redistribution of hydrothermal fluids and locally increased pore pressures. Although changes in geyser activity and earthquake triggering have been documented elsewhere, here we present evidence for changes in a hydrothermal system induced by a large-magnitude event at a great distance, and evidence for the important role hydrothermal systems play in remotely triggering seismicity.

Ground effects and hydrological changes in the Southern Apennines (Italy) in response to the 23 July 1930 earthquake (<i>M<sub>S</sub></i>=6.7)

“…Many anomalous behaviours of aquifers have been noted before, during and after a seismic event: sudden increases/decreases in spring flows, changes in piezometric levels in water wells, and increases in the emanation of deep gases (Gordon, 1970;Sorey and Clark, 1981;Whitehead et al, 1984;Wakita et al, 1985;Igarashi et al, 1992;Briggs, 1994;Curry et al, 1994;Wolf, 1992, 1994;Quilty et al, 1995;Schuster and Murphy, 1996;Balderer et al, 2000;Italiano et al, 2000;Thorson, 2001;Montgomery and Manga, 2003;Husen et al, 2004).…”

“…Effects on fumarole activity at distances of about 100 km from the epicenter seems hard to explain, but correlations between seismicity and volcanic phenomena are well known (Wakita et al, 1985;Hill et al, 2002;Husen et al, 2004). Hill et al (2002) pointed out that earthquakes and volcanoes are linked through plate tectonics and large earthquakes are capable of triggering eruptions within a matter of minutes or days at nearby volcanoes.…”

“…In Central Japan anomalies in gas compositions were observed at fumaroles (at an epicentral distance of 9 km) and three mineral springs (at epicentral distances of 50, 71 and 95 km) about 1-3 months prior to an inland earthquake of M=6.8 on 14 September 1984 (Sugisaki and Sugiura, 1986). Husen et al (2004) report changes in geyser eruption behavior in Yellowstone National Park at very large distances (more than 3000 km from the epicenter) for Denali fault earthquake (Alaska), M=7.9. They interpreted these changes as being induced by dynamic stresses associated with the arrival of large-amplitude surface waves.…”

Hydrological and Geochemical Changes Related to Earthquakes - Examples: Three Great Earthquakes of the XX Century in the Southern Apennines (Italy)

“…Near Venosa (the Vulture volcanic complex, not far from the epicentral zone) an increase in soil temperature was measured; Oddone (1932) imputed it to chemical reaction produced by a water table uplift in layers with Fe and S. Effects on fumarole activity at distances of about 100 km from the epicenter seems hard to explain, but correlations between seismicity and volcanic phenomena are well known (Wakita et al, 1985;Hill et al, 2002;Husen et al, 2004). Hill et al (2002) pointed out that earthquakes and volcanoes are linked through plate tectonics and large earthquakes are capable of triggering eruptions within a matter of minutes or days at nearby volcanoes.…”

“…It is plausible that such effects would occur in Southern Italy which is affected by young active tectonics with frequent strong earthquakes and many volcanically active areas (Pece et al, 1999). Many anomalous behaviours of aquifers have been noted before, during and after a seismic event: sudden increases/decreases in spring flows, changes in piezometric levels in water wells, and increases in the emanation of deep gases (Gordon, 1970;Sorey and Clark, 1981;Whitehead et al, 1984;Wakita et al, 1985;Igarashi et al, 1992;Briggs, 1994;Curry et al, 1994;Wolf, 1992, 1994;Quilty and Roeloffs, 1997;Schuster and Murphy, 1996;Italiano et al, 2000;Thorson, 2001;Montgomery and Manga, 2003;Husen et al, 2004). Characterizing the behaviour of aquifers and detecting anomalies in the late 1930s may be easier than in subsequent years since water resources were less exploited at that time.…”