My research objectives are to characterize and quantify spatial and temporal patterns of temperature, pressure, chemistry, and phase (e.g. liquid or gas) in volcano-hydrothermal systems and relate them to magmatic and/or volcanic activity.
Quantitative understanding of groundwater and gas-rich fluid dynamics in volcanic areas is important for several reasons: 1) pressure, temperature and chemical changes in the hydrothermal system might signal one of the earliest warnings of volcanic unrest, 2) Many of the geochemical, geodetic, and seismic signals measured at the volcano’s surface have hydrothermal origins or magmatic origins modulated by the intervening hydrothermal system, 3) as a major source of hazard such as propellant in steam-driven explosions, lubricant in mudflows, and transport agent for toxic constituents such as arsenic and mercury, 4) guiding exploration and mining of geothermal energy and mineral deposits. To better understand these complex systems I integrate and synthesize hydrologic, geochemical, geologic, and geophysical methods. My research is intended to support the USGS Volcano Hazards Program’s broad goal of lessening the harmful impacts of volcanic activity and the Geothermal Project's goals of exploring reservoirs of hot fluids in the Earth’s crust.
A list of publications can be found below and on Google Scholar
- Hurwitz et al., 2021, Groundwater dynamics at Kīlauea Volcano and vicinity, Hawaiʻi: USGS Prof. Pap. 1867, 28 p.
- Hurwitz, S. & Manga, M., 2017. The fascinating and complex dynamics of geyser eruptions. Ann. Rev. Earth Planet. Sci., 45, 31-59.
- Hurwitz, S., & Lowenstern, J.B., 2014. Dynamics of the Yellowstone hydrothermal system. Rev. Geophys., 52, 375-411.
- Ingebritsen, S.E., Geiger, S., Hurwitz, S., and Driesner, T., 2010. Numerical simulation of magmatic hydrothermal systems. Rev. Geophys., 48(1).
- Water-gas-rock interaction in volcano-hydrothermal systems using field observations, chemical and isotopic data, controlled laboratory experiments and thermodynamic models
- Numerical simulations of volcano-hydrothermal systems
- Modulation of volcanic and geyser activity by cyclic hydrological and climatic forcers and by large earthquakes
- The effects of deglaciation on Yellowstone's hydrothermal system
- Heat transport in volcanic systems
- Dynamics and chemistry of volcanic lakes
- Geyser dynamics - motivation for studying geysers
- The impact of geothermal energy production on groundwater quality
- Development of a field-portable helium isotope analyzer
Education and Certifications
PhD (1999), The Hebrew University of Jerusalem
Science and Products
Sources, fate, and flux of riverine solutes in the Southwest Yellowstone Plateau Volcanic Field, USA
Dating silica sinter (geyserite): A cautionary tale
The prevalence and significance of offset magma reservoirs at arc volcanoes
Radiocarbon dating of silica sinter and postglacial hydrothermal activity in the El Tatio geyser field
Hydrothermal activity in the southwest Yellowstone Plateau Volcanic Field
Temporal variations in scrubbing of magmatic gases at the summit of Kīlauea Volcano, Hawai‘i
Temperature-dependent variations in mineralogy, major element chemistry and the stable isotopes of boron, lithium and chlorine resulting from hydration of rhyolite glass: Constraints from hydrothermal experiments at 150 to 350°C and 25 MPa
Heat and mass transport in a vapor-dominated hydrothermal area in Yellowstone National Park, USA: Inferences from magnetic, electrical, electromagnetic, subsurface temperature and diffuse CO2 flux measurements
Hydrothermal discharge from the El Tatio basin, Atacama, Chile
Hot water in the Long Valley Caldera—The benefits and hazards of this large natural resource
Combining multiphase groundwater flow and slope stability models to assess stratovolcano flank collapse in the Cascade Range
Science and Products
Filter Total Items: 51
Sources, fate, and flux of riverine solutes in the Southwest Yellowstone Plateau Volcanic Field, USASince the 1970s, temporal variations of hydrothermal discharge and thermal output from the numerous hydrothermal features in the Yellowstone Plateau Volcanic Field (YPVF) have been studied by measuring the chloride flux in the major rivers. In this study, the sources, fate, and flux of solutes in the Fall River and its major tributaries, in southwest Yellowstone National Park, were determined. The
Dating silica sinter (geyserite): A cautionary taleWe describe a new effort to date hydrothermal silica sinter deposits (geyserite) from the Upper Geyser Basin of Yellowstone National Park using 14C of co-deposited organic matter, U-series and cosmogenic 10Be methods. A majority of the samples were collected from stratigraphic sections, mainly at Riverside, Giant, and Castle Geysers. Ages obtained from 41 14C analyses range from modern to 12.1 cal
The prevalence and significance of offset magma reservoirs at arc volcanoesDetermining the spatial relations between volcanic edifices and their underlying magma storage zones is fundamental for characterizing long-term evolution and short-term unrest. We compile centroid locations of upper crustal magma reservoirs at 56 arc volcanoes inferred from seismic, magnetotelluric, and geodetic studies. We show that magma reservoirs are often horizontally offset from their assoc
Radiocarbon dating of silica sinter and postglacial hydrothermal activity in the El Tatio geyser fieldThe El Tatio geothermal field in the Chilean Altiplano contains hydrothermal silica sinter deposits overlaying glacial and volcanic units, providing an opportunity to constrain the timing of deglaciation and volcanic activity in an area with sparse absolute chronologies. We obtained 51 new radiocarbon ages and δ13C values on the organic material trapped in these sinter deposits. Based on the δ13C
Hydrothermal activity in the southwest Yellowstone Plateau Volcanic FieldIn the past two decades, the U.S. Geological Survey and the National Park Service have studied hydrothermal activity across the Yellowstone Plateau Volcanic Field (YPVF) to improve the understanding of the magmatic-hydrothermal system and to provide a baseline for detecting future anomalous activity. In 2017 and 2018 we sampled water and gas over a large area in the southwest YPVF and used Landsat
Temporal variations in scrubbing of magmatic gases at the summit of Kīlauea Volcano, Hawai‘iMeasurements of gas compositions and emission rates play a major role in monitoring restless volcanoes. However, thermodynamic calculations imply that scrubbing by groundwater will prevent most HCl and significant SO2 emissions until dry pathways are established, thus leading to underestimates of gas released from magma and magma volumes. Despite the significance, direct evidence for scrubbing is
Temperature-dependent variations in mineralogy, major element chemistry and the stable isotopes of boron, lithium and chlorine resulting from hydration of rhyolite glass: Constraints from hydrothermal experiments at 150 to 350°C and 25 MPaRhyolite-hosted hydrothermal systems in the continental crust contain valuable energy and mineral resources that make them of special interest across several scientific disciplines. Despite extensive research on these systems, the temperature-dependence of chemical reactions between host rocks and aqueous-rich fluids and the mineralogical transformations resulting from these reactions are not well
Heat and mass transport in a vapor-dominated hydrothermal area in Yellowstone National Park, USA: Inferences from magnetic, electrical, electromagnetic, subsurface temperature and diffuse CO2 flux measurementsVapor‐dominated hydrothermal systems are characterized by localized and elevated heat and gas flux. In these systems, steam and gas ascend from a boiling water reservoir, steam condenses beneath a low‐permeability cap layer, and liquid water descends, driven by gravity (“heat pipe” model). We combine magnetic, electromagnetic, and geoelectrical methods and CO2 flux and subsurface temperature measu
Hydrothermal discharge from the El Tatio basin, Atacama, ChileEl Tatio in northern Chile is one of the best-studied geothermal fields in South America. However, there remain open questions about the mass and energy budgets, water recharge rates and residence time in the subsurface, origin of dissolved solutes, and processes affecting the phase and chemical composition of groundwater and surface water. We measured and sampled surface manifestations of the geo
Hot water in the Long Valley Caldera—The benefits and hazards of this large natural resourceThe volcanic processes that have shaped the Long Valley Caldera in eastern California have also created an abundant supply of natural hot water. This natural resource provides benefits to many users, including power generation at the Casa Diablo Geothermal Plant, warm water for a state fish hatchery, and beautiful scenic areas such as Hot Creek gorge for visitors. However, some features can be dan
Combining multiphase groundwater flow and slope stability models to assess stratovolcano flank collapse in the Cascade RangeHydrothermal alteration can create low‐permeability zones, potentially resulting in elevated pore‐fluid pressures, within a volcanic edifice. Strength reduction by rock alteration and high pore‐fluid pressures have been suggested as a mechanism for edifice flank instability. Here we combine numerical models of multiphase heat transport and groundwater flow with a slope‐stability code that incorpor