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
Ca, Sr, O and D isotope approach to defining the chemical evolution of hydrothermal fluids: example from Long Valley, CA, USA
Constraints on the upper crustal magma reservoir beneath Yellowstone Caldera inferred from lake-seiche induced strain observations
Eruptions at Lone Star Geyser, Yellowstone National Park, USA, part 1: energetics and eruption dynamics
Heat flow in vapor dominated areas of the Yellowstone Plateau volcanic field: implications for the thermal budget of the Yellowstone Caldera
Temporal variations of geyser water chemistry in the Upper Geyser Basin, Yellowstone National Park, USA
Mechanics of Old Faithful Geyser, Calistoga, CA
Climate-induced variations of geyser periodicity in Yellowstone National Park, USA
Temperature data from wells in Long Valley Caldera, California
Note from the Hubbert Quorum
Boiling water at Hot Creek— The dangerous and dynamic thermal springs in California’s Long Valley Caldera
River Chemistry and Solute Flux in Yellowstone National Park
Spatial and temporal geochemical trends in the hydrothermal system of Yellowstone National Park: Inferences from river solute fluxes
Science and Products
Filter Total Items: 51
Ca, Sr, O and D isotope approach to defining the chemical evolution of hydrothermal fluids: example from Long Valley, CA, USAWe present chemical and isotopic data for fluids, minerals and rocks from the Long Valley meteoric-hydrothermal system. The samples encompass the presumed hydrothermal upwelling zone in the west moat of the caldera, the Casa Diablo geothermal field, and a series of wells defining a nearly linear, ∼16 km long, west-to-east trend along the likely fluid flow path. Fluid samples were analyzed for the
Constraints on the upper crustal magma reservoir beneath Yellowstone Caldera inferred from lake-seiche induced strain observationsSeiche waves in Yellowstone Lake with a ~78-minute period and heights
Eruptions at Lone Star Geyser, Yellowstone National Park, USA, part 1: energetics and eruption dynamicsGeysers provide a natural laboratory to study multiphase eruptive processes. We present results from a four–day experiment at Lone Star Geyser in Yellowstone National Park, USA. We simultaneously measured water discharge, acoustic emissions, infraredintensity, and visible and infrared video to quantify the energetics and dynamics of eruptions, occurring approximately every three hours. We define f
Heat flow in vapor dominated areas of the Yellowstone Plateau volcanic field: implications for the thermal budget of the Yellowstone CalderaCharacterizing the vigor of magmatic activity in Yellowstone requires knowledge of the mechanisms and rates of heat transport between magma and the ground surface. We present results from a heat flow study in two vapor dominated, acid-sulfate thermal areas in the Yellowstone Caldera, the 0.11 km2 Obsidian Pool Thermal Area (OPTA) and the 0.25 km2 Solfatara Plateau Thermal Area (SPTA). Conductive h
Temporal variations of geyser water chemistry in the Upper Geyser Basin, Yellowstone National Park, USAGeysers are rare features that reflect a delicate balance between an abundant supply of water and heat and a unique geometry of fractures and porous rocks. Between April 2007 and September 2008, we sampled Old Faithful, Daisy, Grand, Oblong, and Aurum geysers in Yellowstone National Park's Upper Geyser Basin and characterized temporal variations in major element chemistry and water isotopes (δ18O,
Mechanics of Old Faithful Geyser, Calistoga, CAIn order to probe the subsurface dynamics associated with geyser eruptions, we measured ground deformation at Old Faithful Geyser of Calistoga, CA. We present a physical model in which recharge during the period preceding an eruption is driven by pressure differences relative to the aquifer supplying the geyser. The model predicts that pressure and ground deformation are characterized by an expone
Climate-induced variations of geyser periodicity in Yellowstone National Park, USAThe geysers of Yellowstone National Park, United States, attract millions of visitors each year, and their eruption dynamics have been the subject of extensive research for more than a century. Although many of the fundamental aspects associated with the dynamics of geyser eruptions have been elucidated, the relationship between external forcing (Earth tides, barometric pressure, and precipitation
Temperature data from wells in Long Valley Caldera, CaliforniaThe 30-by-20-km Long Valley Caldera (LVC) in eastern California (fig.1) formed at 0.76 Ma in a cataclysmic eruption that resulted in the deposition of 600 km? of Bishop Tuff outside the caldera rim (Bailey, 1989). By approximately 0.6 Ma, uplift of the central part of the caldera floor and eruption of rhyolitic lava formed the resurgent dome. The most recent eruptive activity in the area occurred
Note from the Hubbert QuorumNo abstract available.
Boiling water at Hot Creek— The dangerous and dynamic thermal springs in California’s Long Valley CalderaThe beautiful blue pools and impressive boiling fountains along Hot Creek in east-central California have provided enjoyment to generations of visitors, but they have also been the cause of injury or death to some who disregarded warnings and fences. The springs and geysers in the stream bed and along its banks change location, temperature, and flow rates frequently and unpredictably. The hot spri
River Chemistry and Solute Flux in Yellowstone National ParkIntroduction The Yellowstone Volcano Observatory (YVO) was established to 'To strengthen the long-term monitoring of volcanic and earthquake unrest in the Yellowstone National Park region'. Yellowstone National Park is underlain by a voluminous magmatic system overlain by the most active hydrothermal system on Earth. Tracking changes in water and gas chemistry is of great importance because anoma
Spatial and temporal geochemical trends in the hydrothermal system of Yellowstone National Park: Inferences from river solute fluxesWe present and analyze a chemical dataset that includes the concentrations and fluxes of HCO3−, SO42−, Cl−, and F− in the major rivers draining Yellowstone National Park (YNP) for the 2002–2004 water years (1 October 2001 – 30 September 2004). The total (molar) flux in all rivers decreases in the following order, HCO3− > Cl− > SO42− > F−, but each river is characterized by a distinct chemical comp