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USGS2002

Resource-assessment perspectives for unconventional gas systems

Concepts are described for assessing those unconventional gas systems that can also be defined as continous accumulations. Continuous gas accumulations exist more or less independently of the water column and do not owe their existence directly to the bouyancy of gas in water. They cannot be represented in terms of individual, countable fields or pools delineated by downdip water contacts. For these reasons, traditional resource-assessment methods based on estimating the sizes and numbers of undiscovered discrete fields cannot not be applied to continuous accumulations. Specialized assessment methods are required. Unconventional gas systems that are also continous accumulations include coalbed methane, basin-centered gas, so-called tight gas, fractured shale (and chalk) gas, and gas hydrates. Deep-basin and bacterial gas systems may or may not be continuous accumulations, depending on their geologic setting. Two basic resource-assessment approaches have been employed for continous accumulations. The first approach is based on estimates of gas in place. A volumetric estimate of total gas in place is commonly coupled with an overall recovery factor to narrow the assessment scope from a treatment of gas volumes residing in sedimentary strata to a prediction of potential additions to reserves. The second approach is based on the production performance of continous gas reservoirs, as shown empirically by wells and reservoir-simulation models. In these methods, production characteristics (as opposed to gas in place) are the foundation for forecasts of potential additions to reserves.

American Association of Petroleum Geologists Bulle↗

USGS2016

The Lassen hydrothermal system

The active Lassen hydrothermal system includes a central vapor-dominated zone or zones beneath the Lassen highlands underlain by ~240 °C high-chloride waters that discharge at lower elevations. It is the best-exposed and largest hydrothermal system in the Cascade Range, discharging 41 ± 10 kg/s of steam (~115 MW) and 23 ± 2 kg/s of high-chloride waters (~27 MW). The Lassen system accounts for a full 1/3 of the total high-temperature hydrothermal heat discharge in the U.S. Cascades (140/400 MW). Hydrothermal heat discharge of ~140 MW can be supported by crystallization and cooling of silicic magma at a rate of ~2400 km 3 /Ma, and the ongoing rates of heat and magmatic CO 2 discharge are broadly consistent with a petrologic model for basalt-driven magmatic evolution. The clustering of observed seismicity at ~4–5 km depth may define zones of thermal cracking where the hydrothermal system mines heat from near-plastic rock. If so, the combined areal extent of the primary heat-transfer zones is ~5 km 2 , the average conductive heat flux over that area is >25 W/m 2 , and the conductive-boundary length <50 m. Observational records of hydrothermal discharge are likely too short to document long-term transients, whether they are intrinsic to the system or owe to various geologic events such as the eruption of Lassen Peak at 27 ka, deglaciation beginning ~18 ka, the eruptions of Chaos Crags at 1.1 ka, or the minor 1914–1917 eruption at the summit of Lassen Peak. However, there is a rich record of intermittent hydrothermal measurement over the past several decades and more-frequent measurement 2009–present. These data reveal sensitivity to climate and weather conditions, seasonal variability that owes to interaction with the shallow hydrologic system, and a transient 1.5- to twofold increase in high-chloride discharge in response to an earthquake swarm in mid-November 2014.

California↗

USGS2004

Photomosaics of the cathodoluminescence of 60 sections of meteorites and lunar samples

Cathodoluminescence (CL) petrography provides a means of observing petrographic and compositional properties of geological samples not readily observable by other techniques. We report the low-magnification CL images of 60 sections of extraterrestrial materials. The images we report include ordinary chondrites (including type 3 ordinary chondrites and gas-rich regolith breccias), enstatite chondrites, CO chondrites and a CM chondrite, eucrites and a howardite, lunar highland regolith breccias, and lunar soils. The CL images show how primitive materials respond to parent body metamorphism, how the metamorphic history of EL chondrites differs from that of EH chondrites, how dark matrix and light clasts of regolith breccias relate to each other, how metamorphism affects eucrites, the texture of lunar regolith breccias and the distribution of crystallized lunar spherules ("lunar chondrules"), and how regolith working affects the mineral properties of lunar soils. More particularly, we argue that such images are a rich source of new information on the nature and history of these materials and that our efforts to date are a small fraction of what can be done. Copyright 2004 by the American Geophysical Union.

Journal of Geophysical Research E: Planets↗

USGS2014

Report of the committee on chemistry of natural waters, 1938–39

The membership of this Committee is as follows: C. S. Howard (Chairman), United States Geological Survey, Washington, D.C. I. A. Denison, National Bureau of Standards, Washington, D.C. W. P. Kelley, 119 Hilgard Hall, University of California, Berkeley, California A. C. Lane, 22 Arlington Street, Cambridge, Massachusetts C. S. Scofield, Bureau of Plant Industry, United States Department of Agriculture, Washington, D.C. D. G. Thompson, United States Geological Survey, Washington, D.C. T. G. Thompson, University of Washington, Seattle, Washington Studies on the corrosion of metals and soils have been continued at the National Bureau of Standards and a report of the recent findings was published under the title “Correlation of the electrolytic corrosion test with the active corrosiveness of soils,” by I. A. Denison and R. B. Darnielle [J. Res., Nation. Bur. Stan., No. 21, pp. 819‐830, December, 1938], Another paper on this subject by Kirk H. Logan was published under the title “Engineering significance of National Bureau of Standards soil corrosion data” [J. Res. Nation. Bur. Stan., pp. 109–125, January. 1939].

Eos, Transactions, American Geophysical Union↗

USGS2020

Strategic Plan for the North American Breeding Bird Survey, 2020–30

The North American Breeding Bird Survey (BBS) has been the cornerstone of continental bird conservation and management for hundreds of North American bird species in the United States and Canada for more than 50 years. This strategic plan was developed in collaboration with key partners and stakeholders and charts the ambitious course for the BBS over the next decade (2020–30). Using this plan as a guide, the BBS program will set out to improve the breadth and depth of standardized data collection and analytical products; ensure its products are widely used and recognized as the authoritative source for long-term population change information for most birds; and secure adequate resources, internally and through partnerships, to realize the expanded vision of the BBS intended to support avian management needs through 2030.

Circular↗

USGS2012

Potential climate-induced runoff changes and associated uncertainty in four Pacific Northwest estuaries

As part of a larger investigation into potential effects of climate change on estuarine habitats in the Pacific Northwest, we estimated changes in freshwater inputs into four estuaries: Coquille River estuary, South Slough of Coos Bay, and Yaquina Bay in Oregon, and Willapa Bay in Washington. We used the U.S. Geological Survey's Precipitation Runoff Modeling System (PRMS) to model watershed hydrological processes under current and future climatic conditions. This model allowed us to explore possible shifts in coastal hydrologic regimes at a range of spatial scales. All modeled watersheds are located in rainfall-dominated coastal areas with relatively insignificant base flow inputs, and their areas vary from 74.3 to 2,747.6 square kilometers. The watersheds also vary in mean elevation, ranging from 147 meters in the Willapa to 1,179 meters in the Coquille. The latitudes of watershed centroids range from 43.037 degrees north latitude in the Coquille River estuary to 46.629 degrees north latitude in Willapa Bay. We calibrated model parameters using historical climate grid data downscaled to one-sixteenth of a degree by the Climate Impacts Group, and historical runoff from sub-watersheds or neighboring watersheds. Nash Sutcliffe efficiency values for daily flows in calibration sub-watersheds ranged from 0.71 to 0.89. After calibration, we forced the PRMS models with four North American Regional Climate Change Assessment Program climate models: Canadian Regional Climate Model-(National Center for Atmospheric Research) Community Climate System Model version 3, Canadian Regional Climate Model-Canadian Global Climate Model version 3, Hadley Regional Model version 3-Hadley Centre Climate Model version 3, and Regional Climate Model-Canadian Global Climate Model version 3. These are global climate models (GCMs) downscaled with regional climate models that are embedded within the GCMs, and all use the A2 carbon emission scenario developed by the Intergovernmental Panel on Climate Change. With these climate-forcing outputs, we derived the mean change in flow from the period encompassing the 1980s (1971-1995) to the period encompassing the 2050s (2041-2065). Specifically, we calculated percent change in mean monthly flow rate, coefficient of variation, top 5 percent of flow, and 7-day low flow. The trends with the most agreement among climate models and among watersheds were increases in autumn mean monthly flows, especially in October and November, decreases in summer monthly mean flow, and increases in the top 5 percent of flow. We also estimated variance in PRMS outputs owing to parameter uncertainty and the selection of climate model using Latin hypercube sampling. This analysis showed that PRMS low-flow simulations are more uncertain than medium or high flow simulations, and that variation among climate models was a larger source of uncertainty than the hydrological model parameters. These results improve our understanding of how climate change may affect the saltwater-freshwater balance in Pacific Northwest estuaries, with implications for their sensitive ecosystems.

Oregon;Washington↗

USGS2015

Flood-inundation maps for the Hoosic River, North Adams and Williamstown, Massachusetts, from the confluence with the North Branch Hoosic River to the Vermont State line

A series of nine digital flood-inundation maps were developed for an 8-mile reach of the Hoosic River in North Adams and Williamstown, Massachusetts, by the U.S. Geological Survey (USGS) in cooperation with the Federal Emergency Management Agency. The coverage of the maps extends from the confluence with the North Branch Hoosic River to the Vermont State line. Peak flows with 20-, 10-, 4-, 2-, 1-, 0.5-, and 0.2-percent annual exceedance probabilities were computed for the reach from updated flood-frequency analyses. These peak flows were routed through a one-dimensional step-backwater hydraulic model to obtain the corresponding peak water-surface elevations, and to place the tropical storm Irene flood of August 28, 2011 into historical context. The hydraulic model was calibrated by using the current (2014) stage-discharge relation at the USGS streamgage Hoosic River near Williamstown, Massachusetts (01332500), and from documented high-water marks from the tropical storm Irene flood, which had approximately a 1-percent annual exceedance probability. The hydraulic model was used to compute water-surface profiles for flood stages referenced to the streamgage and ranging from 9 feet (ft; 624.45 ft North American Vertical Datum of 1988 [NAVD 1988]), which is near bankfull, to 16.1 ft (631.59 ft NAVD 1988), which exceeds the maximum recorded water level at the streamgage and the National Weather Service major flood stage of 13.0 ft. The mapped stages, 10.9 to 16.1 ft, were selected to match the stages of flows with annual exceedance probabilities between 20 and 0.2 percent, and thus do not fall at exact 1-ft increments. The simulated water-surface profiles were combined with a geographic information system digital elevation model derived from light detection and ranging (lidar) data having a 0.5-ft vertical accuracy to create a set of flood-inundation maps. The availability of the flood-inundation maps, combined with information regarding current (near real-time) stage from USGS streamgage Hoosic River near Williamstown, and forecasted flood stages from the National Weather Service Advanced Hydrologic Prediction Service will provide emergency management personnel and residents with information that is critical for flood response activities such as evacuations and road closures, and post-flood recovery efforts. The flood-inundation maps are nonregulatory, but provide Federal, State, and local agencies and the public with estimates of the potential extent of flooding during selected peak-flow events.

Massachusetts↗

USGS2018

Characterization of peak streamflows and flood inundation of selected areas in southeastern Texas and southwestern Louisiana from the August and September 2017 flood resulting from Hurricane Harvey

Hurricane Harvey made landfall near Rockport, Texas, on August 25, 2017, as a Category 4 hurricane with wind gusts exceeding 150 miles per hour. As Harvey moved inland, the forward motion of the storm slowed down and produced tremendous rainfall amounts over southeastern Texas, with 8-day rainfall amounts exceeding 60 inches in some locations, which is about 15 inches more than average annual amounts of rainfall for eastern Texas and the Texas coast. Historic flooding occurred in Texas as a result of the widespread, heavy rainfall; wind and flood damages were estimated to be $125 billion, and the storm resulted in at least 68 direct fatalities. In the immediate aftermath of the Harvey-related flood event, the U.S. Geological Survey (USGS) and the Federal Emergency Management Agency initiated a cooperative study to evaluate the magnitude of the flood, determine the probability of occurrence, and map the extent of the flood in Texas. Seventy-four USGS streamflow-gaging stations in Texas with at least 15 years of record and no large data gaps in the period of record had a 2017 annual peak streamflow related to Harvey ranking in the top five of all annual peaks for each given station. New peaks of record streamflow were recorded at 40 of the 74 USGS streamflow-gaging stations. The number of years of peak streamflow record for the 74 analyzed streamflow-gaging stations ranged from 18 to 105, with a mean number of 55 years. The annual exceedance probability estimates for the analyzed streamflow-gaging stations ranged from less than 0.2 to 14.0 percent. USGS field crews surveyed 2,123 high-water marks to obtain water-surface elevations, in feet above the North American Vertical Datum of 1988. In some locations, several water-surface elevations were averaged to obtain 1 water-surface elevation, resulting in 1,258 water-surface elevations. Some of these high-water marks were used, along with peak-stage data from USGS streamflow-gaging stations, to create 19 inundation maps to document the areal extent of the maximum depth of the flooding. Digital datasets of the inundation area, modeling boundary, water-depth rasters, and final map products are available from the USGS data release associated with this report ( https://doi.org/10.5066/F7VH5N3N ).

Arkansas, Louisiana, Texas↗

USGS2014

Further tests of permeability with low hydraulic gradients

Many of the water‐bearing formations in the United States have hydraulic gradients of much less than 20 feet to the mile, and some may have gradients of less than one foot to the mile, whereas most laboratory‐ tests of permeability are made with much higher gradients . An investigation was therefore undertaken by the writer, under the direction of 0. E. Meinzer, in the Hydrologic Laboratory of the United States Geological Survey, to determine whether Darcy's law is valid for very low hydraulic gradients —that is, whether under such low gradients the rate of flow remains proportional to the gradient . In a previous paper by Meinzer and the writer (Amer. Geophysical Union,15th annual meeting, pp.405–409, 1934), it was shown that for the sand tested the rate of flow varies directly with the hydraulic gradient down to a gradient of about one foot to the mile. More recently six additional tests have been made on this sand with the same apparatus, and these tests give evidence of the validity of Darcy's law for still lower gradients .

Eos, Transactions, American Geophysical Union↗

USGS2014

Long-term trends of ground-water levels in the United States

Ground-water levels at the end of 1954 were at or near record-low stages throughout most of the southern two-thirds of the United States. These low stages, like those of the early 1930's, have led to frequent expression of the opinion that the water table throughout the country is continuously falling and that we are gradually exhausting our ground-water supplies. A good record of changes in ground-water levels is being obtained by the United States Geological Survey and cooperating State agencies from periodical measurements of water levels in nearly 20,000 observation wells. The records of some of these wells extend back 50 years. Many records are available for the period beginning in 1934. These long-term records indicate that in some areas the ground-water supply is overdeveloped. In the great majority of areas, however, the stage of the water levels correlates with the precipitation. Much of the country has been in drought and the water levels are at a low stage. As the precipitation increases, as it is bound to do later, the water levels will return to higher stages.

Eos, Transactions, American Geophysical Union↗

USGS2008

Differences in evaporation between a floating pan and class a pan on land

Research was conducted to develop a method for obtaining floating pan evaporation rates in a small (less than 10,000 m 2 ) wetland, lagoon, or pond. Floating pan and land pan evaporation data were collected from March 1 to August 31, 2005, at a small natural wetland located in the alluvium of the Canadian River near Norman, Oklahoma, at the U.S. Geological Survey Norman Landfill Toxic Substances Hydrology Research Site. Floating pan evaporation rates were compared with evaporation rates from a nearby standard Class A evaporation pan on land. Floating pan evaporation rates were significantly less than land pan evaporation rates for the entire period and on a monthly basis. Results indicated that the use of a floating evaporation pan in a small free‐water surface better simulates actual physical conditions on the water surface that control evaporation. Floating pan to land pan ratios were 0.82 for March, 0.87 for April, 0.85 for May, 0.85 for June, 0.79 for July, and 0.69 for August.

Journal of the American Water Resources Associatio↗

USGS2011

Summer stream water temperature models for Great Lakes streams: New York

Temperature is one of the most important environmental influences on aquatic organisms. It is a primary driver of physiological rates and many abiotic processes. However, despite extensive research and measurements, synoptic estimates of water temperature are not available for most regions, limiting our ability to make systemwide and large-scale assessments of aquatic resources or estimates of aquatic species abundance and biodiversity. We used subwatershed averaging of point temperature measurements and associated multiscale landscape habitat conditions from over 3,300 lotic sites throughout New York State to develop and train artificial neural network models. Separate models predicting water temperature (in cold, cool, and warm temperature classes) within small catchment–stream order groups were developed for four modeling units, which together encompassed the entire state. Water temperature predictions were then made for each stream segment in the state. All models explained more than 90% of data variation. Elevation, riparian forest cover, landscape slope, and growing degree-days were among the most important model predictors of water temperature classes. Geological influences varied among regions. Predicted temperature distributions within stream networks displayed patterns of generally increasing temperature downstream but were patchy due to the averaging of water temperatures within stream size-classes of small drainages. Models predicted coldwater streams to be most numerous and warmwater streams to be generally associated with the largest rivers and relatively flat agricultural areas and urban areas. Model predictions provide a complete, georeferenced map of summer daytime mean stream temperature potential throughout New York State that can be used for planning and assessment at spatial scales from the stream segment class to the entire state.

New York↗

USGS1994

American White Pelicans at the Molly Islands, in Yellowstone National Park: Twenty-two years of boom-and-bust breeding, 1966-87

Systematic monitoring of nesting and fledging of American White Pelicans ( Pelecanus erythrorhynchos ) breeding on the Molly Islands In Yellowstone Lake was carried on for 20 years between 1966 and 1987. The mean number of pelicans fledged during those years was 214 (±196 SD). In five of those years the number of pelicans fledged was at or near zero. In six other years, the number of young pelicans fledged ranged from 302-650, with four of those years producing record numbers of successfully fledged young. Maximum seasonal levels of Yellowstone Lake reaching 1.6 m or more produced complete or near complete reproductive failures. Conversely, years with maximum lake levels never reaching 1.4 m were most likely to have very good to outstanding fledging success. Also, numbers of days when air temperatures of -8.8° C or colder and daily temperature minimums of -16.6° C, as well as the duration of ice cover on Yellowstone Lake were important modifiers of the numbers of pelicans fledged. Unexpected crustal deformations adjacent to and within the Yellowstone Lake basin induced flooding, representing serious geologic threats to the long-term well being of the Molly Island pelican colony. A baseline breeding population of 546 (± 183 SD) adult pelicans was calculated to have supported this Molly Island colony. Also, the percentage of population change in the computed annual life cycle for 1966-87 was +5%.

Wyoming↗

USGS2014

Ground‐water inventory in the Upper Gila River Valley, New Mexico and Arizona: Scope of investigation and methods used

The Division of Ground Water of the Geological Survey, United States Department of the Interior, has been making an inventory of the water‐resources of the upper Gila River since January 1, 1940. Funds for the project are furnished under a cooperative agreement with the Arizona State Water Commissioner, supplemented by a substantial grant from the United States Engineer Office of the War Department. The State of Arizona wants information regarding the quantity of ground‐water available to supplement surface‐water irrigation. The Army Engineers would like to know the effect that flood‐control structures which may be built on the upper Gila will have on existing relations between river‐flow and ground‐water storage.

Eos, Transactions, American Geophysical Union↗

USGS1969

Lower Llandovery of the northern Appalachians and adjacent regions

Rocks of clearly dated early Llandovery age, as well as rocks that can logically be classed as early Llandovery from their regional relationships, appear to be more widespread than recognized, heretofore, in the northern Appalachians and adjacent regions. Their areal distribution and lithology permit a generalized reconstruction of the paleogeography, which consisted, in general, of three source areas alternating from east to west with three belts of clastic sedimentation. The westernmost clastic belt grades laterally westward into the carbonate rocks of the North American platform. The Central Clastic Belt encloses a belt containing impure carbonates with clastic detritus and clastic interbeds, and, locally, relatively clean carbonate deposits. Llandovery age rocks of the platform include the Manitoulin Dolomite and the Ellis Bay Formation. In the deposits to the east, coeval rocks occur, in part or in whole, within the limy and clastic deposits of the Carys Mills Formation and the Matapedia Group, as well as in the following clastic rock formations: Grimsby, Shawangunk, Tuscarora, Massanutten, Clinch, Smyrna Mills, Perham, Cabano, Weir, Beechhill Cove, Ross Brook, and White Rock.

Maine, New Brunswick, Quebec↗

USGS2009

Method development for analysis of urban dust using scanning electron microscopy with energy dispersive x-ray spectrometry to detect the possible presence of world trade center dust constituents

The collapse of the World Trade Center Towers on September 11, 2001, sent dust and debris across much of Manhattan and in the surrounding areas. Indoor and outdoor dust samples were collected and characterized by U.S. Geological Survey (USGS) scientists using scanning electron microscopy with energy-dispersive spectrometry (SEM/EDS). From this characterization, the U.S. Environmental Protection Agency and USGS developed a particulate screening method to determine the presence of residual World Trade Center dust in the indoor environment using slag wool as a primary "signature". The method describes a procedure that includes splitting, ashing, and sieving of collected dust. From one split, a 10 mg/mL dust/ isopropanol suspension was prepared and 10-30 ??L aliquots of the suspension placed on an SEM substrate. Analyses were performed using SEM/EDS manual point counting for slag wool fibers. Poisson regression was used to identify some of the sources of uncertainty, which are directly related to the small number of fibers present on each sample stub. Preliminary results indicate that the procedure is promising for screening urban background dust for the presence of WTC dust. Consistent sample preparation of reference materials and samples must be performed by each laboratory wishing to use this method to obtain meaningful and accurate results. ?? 2009 American Chemical Society.

Environmental Science & Technology↗

USGS2009

A synthesis of Martian aqueous mineralogy after 1 Mars year of observations from the Mars Reconnaissance Orbiter

Martian aqueous mineral deposits have been examined and characterized using data acquired during Mars Reconnaissance Orbiter's (MRO) primary science phase, including Compact Reconnaissance Imaging Spectrometer for Mars hyperspectral images covering the 0.4-3.9 ??m wavelength range, coordinated with higher-spatial resolution HiRISE and Context Imager images. MRO's new high-resolution measurements, combined with earlier data from Thermal Emission Spectrometer; Thermal Emission Imaging System; and Observatoire pour la Min??ralogie, L'Eau, les Glaces et l'Activiti?? on Mars Express, indicate that aqueous minerals are both diverse and widespread on the Martian surface. The aqueous minerals occur in 9-10 classes of deposits characterized by distinct mineral assemblages, morphologies, and geologic settings. Phyllosilicates occur in several settings: in compositionally layered blankets hundreds of meters thick, superposed on eroded Noachian terrains; in lower layers of intracrater depositional fans; in layers with potential chlorides in sediments on intercrater plains; and as thousands of deep exposures in craters and escarpments. Carbonate-bearing rocks form a thin unit surrounding the Isidis basin. Hydrated silica occurs with hydrated sulfates in thin stratified deposits surrounding Valles Marineris. Hydrated sulfates also occur together with crystalline ferric minerals in thick, layered deposits in Terra Meridiani and in Valles Marineris and together with kaolinite in deposits that partially infill some highland craters. In this paper we describe each of the classes of deposits, review hypotheses for their origins, identify new questions posed by existing measurements, and consider their implications for ancient habitable environments. On the basis of current data, two to five classes of Noachian-aged deposits containing phyllosilicates and carbonates may have formed in aqueous environments with pH and water activities suitable for life. Copyright 2009 by the American Geophysical Union.

Journal of Geophysical Research E: Planets↗

USGS2003

Sulfur geochemistry of hydrothermal waters in Yellowstone National Park, Wyoming, USA. III. An anion-exchange resin technique for sampling and preservation of sulfoxyanions in natural waters

A sampling protocol for the retention, extraction, and analysis of sulfoxyanions in hydrothermal waters has been developed in the laboratory and tested at Yellowstone National Park and Green Lake, NY. Initial laboratory testing of the anion-exchange resin Bio-Rad??? AG1-X8 indicated that the resin was well suited for the sampling, preservation, and extraction of sulfate and thiosulfate. Synthetic solutions containing sulfate and thiosulfate were passed through AG1-X8 resin columns and eluted with 1 and 3 M KCl, respectively. Recovery ranged from 89 to 100%. Comparison of results for water samples collected from five pools in Yellowstone National Park between on-site IC analysis (U.S. Geological Survey mobile lab) and IC analysis of resin-stored sample at SUNY-Stony Brook indicates 96 to 100% agreement for three pools (Cinder, Cistern, and an unnamed pool near Cistern) and 76 and 63% agreement for two pools (Sulfur Dust and Frying Pan). Attempts to extract polythionates from the AG1-X8 resin were made using HCl solutions, but were unsuccessful. Bio-Rad??? AG2-X8, an anion-exchange resin with weaker binding sites than the AG1-X8 resin, is better suited for polythionate extraction. Sulfate and thiosulfate extraction with this resin has been accomplished with KCl solutions of 0.1 and 0.5 M, respectively. Trithionate and tetrathionate can be extracted with 4 M KCl. Higher polythionates can be extracted with 9 M hydrochloric acid. Polythionate concentrations can then be determined directly using ion chromatographic methods, and laboratory results indicate recovery of up to 90% for synthetic polythionate solutions using AG2-X8 resin columns. ?? The Royal Society of Chemistry and the Division of Geochemistry of the American Chemical Society 2003.

Geochemical Transactions↗