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Jacob B. Lowenstern

Publications and source records attributed to Jacob B. Lowenstern.

At least 73 records · Page 4Linked to original sources
USGS2011

Gas and isotope chemistry of thermal features in Yellowstone National Park, Wyoming

This report presents 130 gas analyses and 31 related water analyses on samples collected from thermal features at Yellowstone between 2003 and 2009. An overview of previous studies of gas emissions at Yellowstone is also given. The analytical results from the present study include bulk chemistry of gases and waters and isotope values for water and steam (delta18O, dealtaD), carbon dioxide (delta13C only), methane (delta13C only), helium, neon, and argon. We include appendixes containing photos of sample sites, geographic information system (GIS) files including shape and kml formats, and analytical results in spreadsheets. In addition, we provide a lengthy discussion of previous work on gas chemistry at Yellowstone and a general discussion of the implications of our results. We demonstrate that gases collected from different thermal areas often have distinct chemical signatures, and that differences across the thermal areas are not a simple function of surface temperatures or the type of feature. Instead, gas chemistry and isotopic composition are linked to subsurface lithologies and varying contributions from magmatic, crustal, and meteoric sources.

Wyoming↗
USGS2010

Contamination of basaltic lava by seawater: Evidence found in a lava pillar from Axial Seamount, Juan de Fuca Ridge

A lava pillar formed during the 1998 eruption at Axial Seamount exhibits compositional and textural evidence for contamination by seawater under magmatic conditions. Glass immediately adjacent to anastomosing microfractures within 1 cm of the inner pillar wall is oxidized and significantly enriched in Na and Cl and depleted in Fe and K with respect to that in glassy selvages from the unaffected outer pillar wall. The affected glass contains up to 1 wt % Cl and is enriched by ∼2 wt % Na 2 O relative to unaffected glass, consistent with a nearly 1:1 (molar) incorporation of NaCl. Glass bordering the Cl‐enriched glass in the inner pillar wall is depleted in Na but enriched in K. The presence of tiny (<10 μ m) grains of Cu‐Fe sulfides and Fe sulfides as well as elemental Ni, Ag, and Au in the Na‐depleted, K‐enriched glass of the inner pillar wall implies significant reduction of this glass, presumably by hydrogen generated during seawater contamination and oxidation of lava adjacent to microfractures. We interpret the compositional anomalies we see in the glass of the interior pillar wall as caused by rapid incorporation of seawater into the still‐molten lava during pillar growth, probably on the time scale of seconds to minutes. Only one of seven examined lava pillars shows this effect, and we interpret that seawater has to be trapped in contact with molten lava (inside the lava pillar, in this case) to produce the effects we see. Thus, under the right conditions, seawater contamination of lavas during submarine eruptions is one means by which the oceanic crust can sequester Cl during its global flux cycle. However, since very few recent lava flows have been examined in similar detail, the global significance of this process in effecting Earth's Cl budget remains uncertain.

Geochemistry, Geophysics, Geosystems↗
USGS2009

Volcano monitoring

Volcanoes are not randomly distributed over the Earth's surface. Most are concentrated on the edges of continents, along island chains, or beneath the sea where they form long mountain ranges. More than half of the world's active volcanoes above sea level encircle the Pacific Ocean (see Fig. 1 ). The concept of plate tectonics explains the locations of volcanoes and their relationship to other large-scale geologic features. The Earth's surface is made up of a patchwork of about a dozen large plates and a number of smaller ones that move relative to one another at <1 cm to ~10 cm/yr (about the speed at which fingernails grow). These rigid plates, with average thickness of ~80 km, are separating, sliding past each other, or colliding on top of the Earth's hot, viscous interior. Volcanoes tend to form where plates collide or spread apart ( Fig. 2 ) but can also grow in the middle of a plate, like the Hawaiian volcanoes ( Fig. 3 ). Of the more than 1,500 volcanoes worldwide believed to have been active in the past 10,000 years, 169 are in the United States and its territories ( Ewert et al., 2005 ) (see Fig. 4 ). As of spring 2007, two of these volcanoes, Kilauea and Mount St. Helens, are erupting, while several others, including Mauna Loa, Fourpeaked, Korovin, Veniaminof, and Anatahan, exhibit one or more signs of restlessness, such as anomalous earthquakes, deformation of the volcano's surface, or changes in volume and composition.

Book chapter↗
USGS2008

Establishing major permeability controls in the Mak-Ban geothermal field, Philippines

Recent updating of the conceptual model of the Mak-Ban (Bulalo) geothermal field verified both structural and stratigraphic controls on permeability and connectivity in the reservoir. Two silicic units within the predominantly andesitic production zone were identified from borehole logs, core and drill cuttings. Whole rock chemical data and petrographic analysis confirmed two rhyolite units that consist of partially welded ash-flow tuffs and lava with primary devitrification and vapor-phase alteration textures typical of subaerial rhyolites. U/Pb dating of zircons from the units showed two distinct episodes of silicic volcanism at 352 ± 16 ka and 501 ± 12 ka, respectively. A recent drilling campaign allowed the running of more gamma ray (GR) in tandem with PTS logs. The logs validated the presence of two units with high GR response generally coinciding with permeable zones just below the interpreted top of the reservoir. Naphthalene disulfonate tracer testing defined a predominantly fault-controlled flow path of fluids from the edges of the field into the central production area. Fifteen to 25% of injected tracers were recovered in production wells over a five-year monitoring period. Peak arrival of tracer returns indicated average speeds between 0.1 to 1.3 m/hr, allowing for sufficient time for the fluids to heat up prior to re-emergence in production wells. Although faults are known to be important pathways in most geothermal reservoirs, the identification of specific structures with high connectivities in Mak-Ban provide an important insight on fluid migration from peripheral areas. This information is critical in preparing a reservoir management strategy for addressing the entry of cool marginal recharge into the center of the field.

Mak-Ban geothermal field↗
USGS2007

Spatial and temporal geochemical trends in the hydrothermal system of Yellowstone National Park: Inferences from river solute fluxes

We present and analyze a chemical dataset that includes the concentrations and fluxes of HCO 3 − , SO 4 2− , 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, HCO 3 − > Cl − > SO 4 2− > F − , but each river is characterized by a distinct chemical composition, implying large-scale spatial heterogeneity in the inputs of the various solutes. The data also display non-uniform temporal trends; whereas solute concentrations and fluxes are nearly constant during base-flow conditions, concentrations decrease, solute fluxes increase, and HCO 3 − /Cl − , and SO 4 2− /Cl − increase during the late-spring high-flow period. HCO 3 − /SO 4 2− decreases with increasing discharge in the Madison and Falls Rivers, but increases with discharge in the Yellowstone and Snake Rivers. The non-linear relations between solute concentrations and river discharge and the change in anion ratios associated with spring runoff are explained by mixing between two components: (1) a component that is discharged during base-flow conditions and (2) a component associated with snow–melt runoff characterized by higher HCO 3 − /Cl − and SO 4 2− /Cl − . The fraction of the second component is greater in the Yellowstone and Snake Rivers, which host lakes in their drainage basins and where a large fraction of the solute flux follows thaw of ice cover in the spring months. Although the total river HCO 3 − flux is larger than the flux of other solutes (HCO 3 − /Cl − ≈ 3), the CO 2 equivalent flux is only ∼ 1% of the estimated emission of magmatic CO 2 soil emissions from Yellowstone. No anomalous solute flux in response to perturbations in the hydrothermal system was observed, possibly because gage locations are too distant from areas of disturbance, or because of the relatively low sampling frequency. In order to detect changes in river hydrothermal solute fluxes, sampling at higher frequencies with better spatial coverage would be required. Our analysis also suggests that it might be more feasible to detect large-scale heating or cooling of the hydrothermal system by tracking changes in gas and steam flux than by tracking changes in river solute flux.

Journal of Volcanology and Geothermal Research↗
USGS2007

River Chemistry and Solute Flux in Yellowstone National Park

Introduction 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 anomalous fluxes might signal one of the earliest warnings of volcanic unrest. Because of the tremendous number, chemical diversity, and large aerial coverage of Yellowstone's thermal features, it remains daunting to monitor individual features that might serve as proxies for anomalous activity in the hydrothermal system. Sampling rivers provides some advantages, because they integrate chemical fluxes over a very large area and therefore, river fluxes may reveal large-scale spatial patterns (Hurwitz et al., 2007). In addition, based on the application of the chloride-enthalpy method (Fournier, 1979), quantifying chloride flux in rivers provides an estimate of the total heat discharge from the Yellowstone volcanic system (Norton and Friedman 1985; Fournier, 1989; Friedman and Norton, in press). Intermittent sampling of the large rivers draining Yellowstone National Park began in the 1960's (Fournier et al., 1976) and continuous sampling has been carried out since water year (1 October - 30 September) 1983 excluding water years 1995 and 1996 (Norton and Friedman, 1985, 1991; Friedman and Norton, 1990, 2000, 2007). Between 1983 and 2001 only Cl concentrations and fluxes were determined. Starting in water year 2002, the concentrations and fluxes of other anions of possible magmatic origin (F-, Br-, HCO3- , and SO42-) were also determined, and several new sampling sites were established (Hurwitz et al., 2007). The ongoing sampling and analysis of river solute flux is a key component in the current monitoring program of YVO, and it is a collaboration between the U.S. Geological Survey and Yellowstone National Park.

Data Series↗
USGS2007

Preliminary Assessment of Volcanic and Hydrothermal Hazards in Yellowstone National Park and Vicinity

Possible future violent events in the active hydrothermal, magmatic, and tectonic system of Yellowstone National Park pose potential hazards to park visitors and infrastructure. Most of the national park and vicinity are sparsely populated, but significant numbers of people as well as park resources could nevertheless be at risk from these hazards. Depending on the nature and magnitude of a particular hazardous event and the particular time and season when it might occur, 70,000 to more than 100,000 persons could be affected; the most violent events could affect a broader region or even continent-wide areas. This assessment of such hazards is presented both as a guide for future activities of the Yellowstone Volcano Observatory (YVO) and to aid appropriate response planning by the National Park Service and surrounding agencies and communities. Although the assessment is presented here in some technical detail, this summary is intended to be understandable to non-scientists. The principal conclusions also will be made available in other forms, more accessible to general readers.

Open-File Report↗
USGS2007

Volcano Hazards Assessment for Medicine Lake Volcano, Northern California

Medicine Lake volcano (MLV) is a very large shield-shaped volcano located in northern California where it forms part of the southern Cascade Range of volcanoes. It has erupted hundreds of times during its half-million-year history, including nine times during the past 5,200 years, most recently 950 years ago. This record represents one of the highest eruptive frequencies among Cascade volcanoes and includes a wide variety of different types of lava flows and at least two explosive eruptions that produced widespread fallout. Compared to those of a typical Cascade stratovolcano, eruptive vents at MLV are widely distributed, extending 55 km north-south and 40 km east-west. The total area covered by MLV lavas is >2,000 km2, about 10 times the area of Mount St. Helens, Washington. Judging from its long eruptive history and its frequent eruptions in recent geologic time, MLV will erupt again. Although the probability of an eruption is very small in the next year (one chance in 3,600), the consequences of some types of possible eruptions could be severe. Furthermore, the documented episodic behavior of the volcano indicates that once it becomes active, the volcano could continue to erupt for decades, or even erupt intermittently for centuries, and very likely from multiple vents scattered across the edifice. Owing to its frequent eruptions, explosive nature, and proximity to regional infrastructure, MLV has been designated a 'high threat volcano' by the U.S. Geological Survey (USGS) National Volcano Early Warning System assessment. Volcanic eruptions are typically preceded by seismic activity, but with only two seismometers located high on the volcano and no other USGS monitoring equipment in place, MLV is at present among the most poorly monitored Cascade volcanoes.

Scientific Investigations Report↗
USGS2007

Chronology of postglacial eruptive activity and calculation of eruption probabilities for Medicine Lake volcano, northern California

Medicine Lake volcano has had 4 eruptive episodes in its postglacial history (since 13,000 years ago) comprising 16 eruptions. Time intervals between events within the episodes are relatively short, whereas time intervals between the episodes are much longer. An updated radiocarbon chronology for these eruptions is presented that uses paleomagnetic data to constrain the choice of calibrated ages. This chronology is used with exponential, Weibull, and mixed-exponential probability distributions to model the data for time intervals between eruptions. The mixed exponential distribution is the best match to the data and provides estimates for the conditional probability of a future eruption given the time since the last eruption. The probability of an eruption at Medicine Lake volcano in the next year from today is 0.00028.

California↗
USGS2007

Systematics of Water Temperature and Flow at Tantalus Creek During Calendar Year 2005, Norris Geyser Basin, Yellowstone National Park, Wyoming

We analyze data for stream flow and water temperature from Tantalus Creek in the Norris Geyser Basin and their relationship to air temperature, precipitation, and geyser eruptions during calendar year 2005. The creek is of interest because it is the primary drainage of the Norris Geyser Basin and carries a very high proportion of thermal water derived directly from hot springs. Two separate diurnal patterns emerge - (1) a winter pattern where increases in water temperature and stream flow closely track those of air temperature and (2) a summer pattern where water and air temperature are closely aligned but stream flow declines once water temperature reaches its daily maximum. The winter pattern is present when the daily average temperature consistently drops below 0 ?C whereas the summer pattern is recognizable when the daily average temperature regularly exceeds 0 ?C. Spring and fall systematics are much more irregular, although both summer and winter patterns can be discerned occasionally during those seasons. We interpret increases in stream flow associated with the winter pattern to result from addition of locally sourced melt water (both snow and soil-bound ice) that increases in abundance once temperatures increase in the morning. Melting is facilitated by the warm ground temperatures in the geyser basin, which are significantly higher than air temperatures in the winter. The summer pattern appears to be strongly affected by increased evaporation in the afternoon, decreasing flow and cooling the remaining water. Discharge from eruptions at Echinus Geyser are clearly visible as peaks in the hydrograph, and indicate that water from this geyser reach the Tantalus weir in 80 to 90 minutes, reflecting a slug of water that travels about 0.4 m s-1.

Scientific Investigations Report↗
USGS2006

Monitoring super-volcanoes: Geophysical and geochemical signals at Yellowstone and other large caldera systems

Earth's largest calderas form as the ground collapses during immense volcanic eruptions, when hundreds to thousands of cubic kilometres of magma are explosively withdrawn from the Earth's crust over a period of days to weeks. Continuing long after such great eruptions, the resulting calderas often exhibit pronounced unrest, with frequent earthquakes, alternating uplift and subsidence of the ground, and considerable heat and mass flux. Because many active and extinct calderas show evidence for repetition of large eruptions, such systems demand detailed scientific study and monitoring. Two calderas in North America, Yellowstone (Wyoming) and Long Valley (California), are in areas of youthful tectonic complexity. Scientists strive to understand the signals generated when tectonic, volcanic and hydrothermal (hot ground water) processes intersect. One obstacle to accurate forecasting of large volcanic events is humanity's lack of familiarity with the signals leading up to the largest class of volcanic eruptions. Accordingly, it may be difficult to recognize the difference between smaller and larger eruptions. To prepare ourselves and society, scientists must scrutinize a spectrum of volcanic signals and assess the many factors contributing to unrest and toward diverse modes of eruption. ?? 2006 The Royal Society.

Philosophical Transactions of the Royal Society A:↗
USGS2005

Steam explosions, earthquakes, and volcanic eruptions -- what's in Yellowstone's future?

Yellowstone, one of the world’s largest active volcanic systems, has produced several giant volcanic eruptions in the past few million years, as well as many smaller eruptions and steam explosions. Although no eruptions of lava or volcanic ash have occurred for many thousands of years, future eruptions are likely. In the next few hundred years, hazards will most probably be limited to ongoing geyser and hot-spring activity, occasional steam explosions, and moderate to large earthquakes. To better understand Yellowstone’s volcano and earthquake hazards and to help protect the public, the U.S. Geological Survey, the University of Utah, and Yellowstone National Park formed the Yellowstone Volcano Observatory, which continuously monitors activity in the region.

Wyoming↗
USGS2004

What makes hydromagmatic eruptions violent? Some insights from the Keanakāko'i Ash, Kı̄lauea Volcano, Hawai'i

Volcanic eruptions at the summit of Kilauea Volcano, Hawai'i, are of two dramatically contrasting types: (1) benign lava flows and lava fountains; and (2) violent, mostly prehistoric eruptions that dispersed tephra over hundreds of square kilometers. The violence of the latter eruptions has been attributed to mixing of water and magma within a wet summit caldera; however, magma injection into water at other volcanoes does not consistently produce widespread tephras. To identify other factors that may have contributed to the violence of these eruptions, we sampled tephra from the Keanakako'i Ash, the most recent large hydromagmatic deposit, and measured vesicularity, bubble-number density and dissolved volatile content of juvenile matrix glass to constrain magma ascent rate and degree of degassing at the time of quenching. Bubble-number densities (9X10 (super 4) -1X10 (super 7) cm (super -3) ) of tephra fragments exceed those of most historically erupted Kilauean tephras (3X10 (super 3) -1.8X10 (super 5) cm (super -3) ), and suggest exceptionally high magma effusion rates. Dissolved sulfur (average=330 ppm) and water (0.15-0.45 wt.%) concentrations exceed equilibrium-saturation values at 1 atm pressure (100-150 ppm and approximately 0.09%, respectively), suggesting that clasts quenched before equilibrating to atmospheric pressure. We interpret these results to suggest rapid magma injection into a wet crater, perhaps similar to continuous-uprush jets at Surtsey. Estimates of Reynolds number suggest that the erupting magma was turbulent and would have mixed with surrounding water in vortices ranging downward in size to centimeters. Such fine-scale mixing would have ensured rapid heat exchange and extensive magma fragmentation, maximizing the violence of these eruptions.

Hawaii↗
USGS1999

Gas and Isotope Geochemistry of 81 Steam Samples from Wells in The Geysers Geothermal Field, Sonoma and Lake Counties, California

The Geysers geothermal field in northern California, with about 2000-MW electrical capacity, is the largest geothermal field in the world. Despite its importance as a resource and as an example of a vapor-dominated reservoir, very few complete geochemical analyses of the steam have been published (Allen and Day, 1927; Truesdell and others, 1987). This report presents data from 90 steam, gas, and condensate samples from wells in The Geysers geothermal field in northern California. Samples were collected between 1978 and 1991. Well attributes include sampling date, well name, location, total depth, and the wellhead temperature and pressure at which the sample was collected. Geochemical characteristics include the steam/gas ratio, composition of noncondensable gas (relative proportions of CO2, H2S, He, H2, O2, Ar, N2, CH4, and NH3), and isotopic values for deltaD and delta18O of H2O, delta13C of CO2, and delta34S of H2S. The compilation includes 81 analyses from 74 different production wells, 9 isotopic analyses of steam condensate pumped into injection wells, and 5 complete geochemical analyses on gases from surface fumaroles and bubbling pools. Most samples were collected as saturated steam and plot along the liquid-water/steam boiling curve. Steam-togas ratios are highest in the southeastern part of the geothermal field and lowest in the northwest, consistent with other studies. Wells in the Northwest Geysers are also enriched in N2/Ar, CO2 and CH4, deltaD, and delta18O. Well discharges from the Southeast Geysers are high in steam/gas and have isotopic compositions and N2/Ar ratios consistent with recharge by local meteoric waters. Samples from the Central Geysers show characteristics found in both the Southeast and Northwest Geysers. Gas and steam characteristics of well discharges from the Northwest Geysers are consistent with input of components from a high-temperature reservoir containing carbonrich gases derived from the host Franciscan rocks. Throughout the geothermal field, the carbon-isotopic composition of CO2 is consistent with derivation of carbon from Franciscan metasedimentary rocks. NH3 concentrations are high in most Geysers well fluids, and are 2-3 orders of magnitude greater than would be expected in a the gas phase exhibiting homogeneous equilibrium at normal reservoir temperatures and pressures. Evidently, NH3 is flushed from the Franciscan host rocks at a rate that exceeds the reaction rate for NH3 breakdown. Many wells show clear influence by fluids from reinjection wells where steam condensate has been pumped back into the geothermal reservoir. Six wells were resampled over the time period of this study. One of these six wells was strongly affected by a nearby injection well. Three of the six resampled wells showed some signs of decreasing liquid/ steam within the geothermal reservoir, consistent with 'drying out' of the reservoir due to steam withdrawal. However, two wells exhibited little change. Analyses of gases from five surface manifestations (fumaroles and bubbling pools) are roughly similar to the deeper geothermal samples in both chemical and isotopic composition, but are lower in soluble gases that dissolve in groundwater during transit toward the surface.

Open-File Report↗
USGS1999

Compilation of gas geochemistry and isotopic analyses from The Geysers geothermal field: 1978-1991

We present 45 chemical and isotopic analyses from well discharges at The Geysers geothermal field and summarize the most notable geochemical trends. H 2 and H 2 S concentrations are highest in the Southeast Geysers, where steam samples have δD and δ 18 O values that reflect replenishment by meteoric water. In the Northwest Geysers, samples are enriched in gas/steam, CO 2 , CH 4 , and N 2 /Ar relative to the rest of the field, and contain steam that is elevated in δD and δ18O, most likely due to substantial contributions from Franciscan-derived fluids. The δ13C of CO 2 , trends in CH 4 vs. N 2 , and abundance of NH 3 indicate that the bulk of the non-condensable gases are derived from thermal breakdown of organic materials in Franciscan meta-sediments.

Geothermal Resources Council Transactions↗
USGS1999

Geochemistry of waters from springs, wells, and snowpack on and adjacent to Medicine Lake volcano, northern California

Chemical analyses of waters from cold springs and wells of the Medicine Lake volcano and surrounding region indicate small chloride anomalies that may be due to water-rock interaction or limited mixing with high-temperature geothermal fluids. The Fall River Springs (FRS) with a combined discharge of approximately 37 m3/s, show a negative correlation between chloride (Cl) and temperature, implying that the Cl is not derived from a high-temperature geothermal fluid. The high discharge from the FRS indicates recharge over a large geographic region. Chemical and isotopic variations in the FRS show that they contain a mixture of three distinct waters. The isotopic composition of recharge on and adjacent to the volcano are estimated from the isotopic composition of snow and precipitation amounts adjusted for evapotranspiration. Enough recharge of the required isotopic composition (-100 parts per thousand ??D) is available from a combination of the Medicine Lake caldera, the Fall River basin and the Long Bell basin to support the slightly warmer components of the FRS (32 m3/s). The cold-dilute part of the FRS (approximately 5 m3/s) may recharge in the Bear Creek basin or at lower elevations in the Fall River basin.

Geothermal Resources Council Transactions↗
USGS1994

The role of magmas in the formation of hydrothermal ore deposits

Magmatic fluids, both vapour and hypersaline liquid, are a primary source of many components in hydrothermal ore deposits formed in volcanic arcs. These components, including metals and their ligands, become concentrated in magmas in various ways from various sources, including subducted oceanic crust. Leaching of rocks also contributes components to the hydrothermal fluid—a process enhanced where acid magmatic vapours are absorbed by deeply circulating meteoric waters. Advances in understanding the hydrothermal systems that formed these ore deposits have come from the study of their active equivalents, represented at the surface by hot springs and volcanic fumaroles.

Nature↗