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At least 523 records · Page 29Linked to original sources
USGS2013

Assessment of undiscovered conventional oil and gas resources of the Western Canada Sedimentary Basin, Canada, 2012

The U.S. Geological Survey recently completed a geoscience-based assessment of undiscovered oil and gas resources of provinces within the Western Canada Sedimentary Basin. The Western Canada Sedimentary Basin primarily comprises the (1) Alberta Basin Province of Alberta, eastern British Columbia, and the southwestern Northwest Territories; (2) the Williston Basin Province of Saskatchewan, southeastern Alberta, and southern Manitoba; and (3) the Rocky Mountain Deformed Belt Province of western Alberta and eastern British Columbia. This report is part of the U.S. Geological Survey World Petroleum Resources Project assessment of priority geologic provinces of the world. The assessment was based on geoscience elements that define a total petroleum system (TPS) and associated assessment unit(s). These elements include petroleum source rocks (geochemical properties and petroleum generation, migration, and accumulation), reservoir description (reservoir presence, type, and quality), and petroleum traps (trap and seal types, and timing of trap and seal formation relative to petroleum migration). Using this framework, the Elk Point-Woodbend Composite TPS, Exshaw-Fernie-Mannville Composite TPS, and Middle through Upper Cretaceous Composite TPS were defined, and four conventional assessment units within the total petroleum systems were quantitatively assessed for undiscovered resources in the Western Canada Sedimentary Basin.

Fact Sheet↗
USGS2021

Geometry of the Bushveld Complex from 3D potential field modelling

A full three-dimensional (3D) potential field model of the central and southern Bushveld Complex reveals information about the Complex in areas obscured by younger geological cover. Previously, two-dimensional gravity models and a few magnetic models limited to certain sections of the Bushveld Complex have been used to propose geometries for the Rustenburg Layered Suite, especially in the western and eastern lobes. These models were often used to support different emplacement models. Although these models provided valuable information, two-and-a-half-dimensional (2.5D) potential field modelling is not well suited to modelling complex 3D geology. Also, in most cases, only the magnetic or gravity data were modelled, but jointly modelling both data sets better constrains the results, as was shown recently for a 3D model of the northern lobe. Joint 3D modelling of regional gravity and magnetic data combined with published crustal thickness models derived from broadband seismic tomography studies and constrained by density and susceptibility data, geologic mapping, boreholes and seismic reflection data were used to create a 3D model of the central and southeastern sections of the Bushveld Complex, as well as the southern part of the northern lobe. The model shows a complex geometry with thick continuous Rustenburg Layered Suite S in most of the western and southeastern lobes, but less continuous Rustenburg Layered Suite in the eastern lobe. Large domes or thick granites and granophyre in the latter interrupt the continuity of the Rustenburg Layered Suite and the western and eastern lobes are strictly speaking only partially connected in places. However, they are not separate intrusions, but one disconnected by pre-existing and synmagmatic updoming. Three possible feeders were modelled in the northern, western, and south-eastern lobes.

Precambrian Research↗
USGS2016

The Department of the Interior Southeast Climate Science Center synthesis report 2011–15—Projects, products, and science priorities

Introduction In 2009, the U.S. Department of the Interior (DOI) Secretary Ken Salazar established a network of eight regional Climate Science Centers (CSCs) that, along with the Landscape Conservation Cooperatives (LCCs), would help define and implement the Department's climate adaptation response. The Southeast Climate Science Center (SE CSC) was established at North Carolina State University (NCSU) in Raleigh, North Carolina, in 2010, under a 5-year cooperative agreement with the U.S. Geological Survey (USGS), to identify and address the regional challenges presented by climate change and variability in the Southeastern United States. All eight regional CSC hosts, including NCSU, were selected through a competitive process. Since its opening, the focus of the SE CSC has been on working with partners in the identification and development of research-based information that can assist managers, including cultural and natural resource managers, in adapting to global change processes, such as climate and land use change, that operate at local to global scales and affect resources important to the DOI mission. The SE CSC was organized to accomplish three goals: Provide co-produced, researched based, actionable science that supports transparent global change adaptation decisions . Convene conversations among decision makers, scientists, and managers to identify key ecosystem adaptation decisions driven by climate and land use change, the values and objectives that will be used to make decisions, and the research-based information needed to assess adaptation options . Build the capacity of natural resource professionals, university faculty, and students to understand and frame natural resource adaptation decisions and develop and use research-based information to make adaptation decisions . This report provides an overview of the SE CSC and the projects developed by the SE CSC since its inception. An important goal of this report is to provide a framework for understanding the evolution of the SE CSC science agenda, which has evolved over the first 5 years of the Center’s operation.

Open-File Report↗
USGS1995

Water-resources investigations in Wisconsin, 1995

The statewide average precipitation of 30.66 inches for the 1994 water year was 96 percent of the normal annual precipitation of 31.79 inches for water years 1961-90. Average precipitation values ranged from 81 percent of normal in southeastern Wisconsin to 103 percent of normal in west-central Wisconsin (Pamela Naber Knox, UW-Extension, Geological and Natural History Survey, written commun., 1994). Runoff was variable for rivers throughout the State ranging from 60 percent in southeast Wisconsin to 142 percent in west-central Wisconsin. Runoff was lowest (60 percent of the average annual runoff from 1972-94) for the Pike River near Racine. Runoff was highest (142 percent of the average annual runoff from 1915-19, 1935-94) for the Trempealeau River at Dodge. Departure of runoff in the 1994 water year as a percent of long-term average runoff in the State are shown in Figure 4.

Wisconsin↗
USGS2012

A benthic-macroinvertebrate index of biotic integrity and assessment of conditions in selected streams in Chester County, Pennsylvania, 1998-2009

The Stream Conditions of Chester County Biological Monitoring Network (Network) was established by the U.S. Geological Survey and the Chester County Water Resources Authority in 1969. Chester County encompasses 760 square miles in southeastern Pennsylvania and has a rapidly expanding population. Land-use change has occurred in response to this continual growth, as open space, agricultural lands, and wooded lands have been converted to residential and commercial lands. In 1998, the Network was modified to include 18 fixed-location sites and 9 flexible-location sites. Sites were sampled annually in the fall (October-November) during base-flow conditions for water chemistry, instream habitat, and benthic macroinvertebrates. A new set of 9 flexible-location sites was selected each year. From 1998 to 2009, 213 samples were collected from the 18 fixed-location sites and 107 samples were collected from the 84 flexible-location sites. Eighteen flexible-location sites were sampled more than once over the 12-year period; 66 sites were sampled only once. Benthic-macroinvertebrate data from samples collected during 1998-2009 were used to establish the Chester County Index of Biotic Integrity (CC-IBI). The CC-IBI was based on the methods and metrics outlined in the Pennsylvania Department of Environmental Protection's "A Benthic Index of Biotic Integrity for Wadeable Freestone Streams in Pennsylvania." The resulting CC-IBI consists of scores for benthic-macroinvertebrate samples collected from sites in the Network that related to reference conditions in Chester County. Mean CC-IBI scores for 18 fixed-location sites ranged from 37.21 to 88.92. Thirty-nine percent of the 213 samples collected at the 18 fixed-location sites had a CC-IBI score less than 50; 33 percent, 50 to 70; 28 percent, greater than 70. CC-IBI scores from the 107 flexible-location samples ranged from 23.48 to 99.96. Twenty-five percent of the 107 samples collected at the flexible-location sites had a CC-IBI score less than 50; 33 percent, 50 to 70; and 42 percent, greater than 70. Factors that were found to affect CC-IBI scores are nutrient concentrations, habitat conditions, and percent of wooded and urban land use. A positive relation was determined between mean CC-IBI scores and mean total habitat scores for the 18 fixed-location sites. CC-IBI scores were most strongly affected by stream bank vegetative protection, embeddedness, riparian zone width, and sediment deposition. The highest CC-IBI scores were associated with sites that had greater than 28 percent wooded-wetland-water land use, less than 5 percent urban land use, and no municipal wastewater discharges within 10 miles upstream from the sampling site. The lowest CC-IBI scores were associated with sites where urban land use was greater than 15 percent or a municipal wastewater discharge was within 10 miles upstream from the sampling reach. The Mann Kendall test for trends was used to determine trends in CC-IBI scores and concentrations of nitrate, orthophosphate, and chloride for the 18 fixed-location sites. A positive trend in CC-IBI was determined for six sites, and a negative trend was determined for one site. Positive trends in nitrate concentrations were determined for 4 of the 18 fixed-location sites, and a negative trend in orthophosphate concentrations was determined for 1 of the 18 fixed-location sites. Positive trends in chloride concentrations were determined for 16 of the 18 fixed-location sites.

Pennsylvania↗
USGS2017

Hydrogeology and water quality of sand and gravel aquifers in McHenry County, Illinois, 2009–14, and comparison to conditions in 1979

Baseline conditions for the sand and gravel aquifers (groundwater) in McHenry County, Illinois, were assessed using data from a countywide network of 44 monitoring wells collecting continuous water-level data from 2009–14. In 2010, water-quality data were collected from 41 of the monitoring wells, along with five additional monitoring wells available from the U.S. Geological Survey National Water Quality Assessment Program. Periodic water-quality data were collected from 2010–14 from selected monitoring wells. The continuous water-level data were used to identify the natural and anthropogenic factors that influenced the water levels at each well. The water-level responses to natural influences such as precipitation, seasonal and annual variations, barometric pressure, and geology, and to anthropogenic influences such as pumping were used to determine (1) likely hydrogeologic setting (degree of aquifer confinement and interconnections) that, in part, are related to lithostratigraphy; and (2) areas of recharge and discharge related to vertical flow directions. Water-level trends generally were determined from the 6 years of data collection (2009–14) to infer effects of weather variability (drought) on recharge. Precipitation adds an estimated 2.4 inches per year of recharge to the aquifer. Some of this recharge is subsequently discharged to streams and some is discharged to supply wells. A few areas in the eastern half of the county had higher average recharge rates, indicating a need for adequate protection of these recharge areas. Downward vertical flow gradients in upland areas indicate that recharge to the confined aquifer units occurs near upland areas. Upward vertical flow gradients in lowland areas indicate discharge at locations of surface water and groundwater interaction (wetlands, ponds, and streams). Monitoring wells were sampled for major and minor ions, metals, and nutrients and a subset of wells was sampled for trace elements, dissolved gases, pesticides, and volatile organic compounds. The results were compared to health ‑ based and aesthetically based standards, which include the U.S. Environmental Protection Agency Maximum Contaminant Level (EPA MCL), and EPA Secondary Maximum Contaminant Levels (SMCL), as well as EPA Health-based Standards Drinking Water Advisories. Health‑based standards were exceeded for arsenic in 22 percent, sodium in 20 percent, and nitrates in 2 percent of the monitoring wells sampled. Aesthetically based standards were exceeded for total dissolved solids in 33 percent, chloride in 11 percent, iron in 85 percent, and manganese in 30 percent of the wells sampled. Many of these same constituents, such as arsenic, iron, and manganese, are naturally occurring but become elevated in areas that have anoxic, mixed, and suboxic conditions. Some areas of potential vulnerability to anthropogenic-sourced constituents in the sand and gravel aquifers were evidenced by trace amounts of volatile organic compounds and pesticides detected in water-quality samples from shallow wells (total depth less of than 46 feet below land surface) near urban settings, and by the detection of elevated major ions (chloride, sodium, magnesium, and calcium) associated, in part, with road-salt applications. Source analysis for chloride indicates mixtures of road salt, water softeners, and sewage. Continuously measured specific conductance values were used as a surrogate for continuously measured chloride concentrations in the groundwater. The estimated chloride concentrations generally were highest in spring and lowest in summer, and occasionally peak during spring melt. Overall, the range of concentrations varied depending on the local thickness and hydraulic conductivity of the aquifer. Water levels and water quality from the countywide groundwater monitoring network were compared to water levels and water-quality results in 1979 from a previous U.S. Geological Survey study. Potentiometric surface maps show areas with inferred decreases of water levels near the southern and southeastern areas of McHenry County. Significant increases were noted for total dissolved solids and specific conductance. Chloride concentrations increased as much as 521 percent in three of six wells resampled in 2015 from the previous study.

Illinois↗
USGS1999

Soil-calcium depletion linked to acid rain and forest growth in the eastern United States

Since the discovery of acid rain in the 1970's, scientists have been concerned that deposition of acids could cause depletion of calcium in forest soils. Research in the 1980's showed that the amount of calcium in forest soils is controlled by several factors that are difficult to measure. Further research in the 1990's, including several studies by the U.S. Geological Survey, has shown that (1) calcium in forest soils has decreased at locations in the northeastern and southeastern U.S., and (2) acid rain and forest growth (uptake of calcium from the soil by roots) are both factors contributing to calcium depletion.

Water-Resources Investigations Report↗
USGS1977

Platinum, palladium, and rhodium in volcanic and plutonic rocks from the Gravina-Nutzotin belt, Alaska

The Gravina-Nutzotin belt of Middle (?) Jurassic to middle Cretaceous sedimentary and volcanic rocks in south and southeastern Alaska includes concentrically zoned ultramafic complexes known to contain platinum-group metals. Previous isotopic, petrologic, and geologic studies suggested a close relation in time and space between the volcanic rocks and the ultramafic complexes. Interpretation of 40 analyses for platinum, palladium, and rhodium in volcanic and plutonic rocks of the belt indicates a strong geochemical correlation between the two groups of rocks and is in support of their being cogenetic either from directly connected magma chambers and flows or indirectly by selective concentration processes from similar mantle material.

Alaska↗
USGS2013

Investigation of the structure and lithology of bedrock concealed by basin fill, using ground-based magnetic-field-profile data acquired in the San Rafael Basin, southeastern Arizona

Data on the Earth’s total-intensity magnetic field acquired near ground level and at measurement intervals as small as 1 m include information on the spatial distribution of nearsurface magnetic dipoles that in many cases are unique to a specific lithology. Such spatial information is expressed in the texture (physical appearance or characteristics) of the data at scales of hundreds of meters to kilometers. These magnetic textures are characterized by several descriptive statistics, their power spectrum, and their multifractal spectrum. On the basis of a graphical comparison and textural characterization, ground-based magnetic-field profile data can be used to estimate bedrock lithology concealed by as much as 100 m of basin fill in some cases, information that is especially important in assessing and exploring for concealed mineral deposits. I demonstrate that multifractal spectra of ground-based magnetic-field-profile data can be used to differentiate exposed lithologies and that the shape and position of the multifractal spectrum of the ground-based magnetic-field-profile of concealed lithologies can be matched to the upward-continued multifractal spectrum of an exposed lithology to help distinguish the concealed lithology. In addition, ground-based magnetic-field-profile data also detect minute differences in the magnetic susceptibility of rocks over small horizontal and vertical distances and so can be used for precise modeling of bedrock geometry and structure, even when that bedrock is concealed by 100 m or more of nonmagnetic basin fill. Such data contain valuable geologic information on the bedrock concealed by basin fill that may not be so visible in aeromagnetic data, including areas of hydrothermal alteration, faults, and other bedrock structures. Interpretation of these data in the San Rafael Basin, southeastern Arizona, has yielded results for estimating concealed lithologies, concealed structural geology, and a concealed potential mineral-resource target.

Arizona↗
USGS2023

Characterization of peak streamflows and flooding in select areas of Pennsylvania from the remnants of Hurricane Ida, September 1–2, 2021

Pennsylvania experienced heavy rainfall on September 1 and 2, 2021, as the remnants of Hurricane Ida swept over parts of the State. Much of eastern and south-central Pennsylvania received 5 to 10 inches of rain, and most of the rainfall fell within little more than 6 hours. Southeastern Pennsylvania experienced widespread, substantial flooding, and the city of Philadelphia and surrounding areas were particularly affected by the flooding. U.S. Geological Survey (USGS) streamgages registered peak streamflows of record at 19 locations, and 52 locations experienced top 5 peak streamflows for the period of record and an annual exceedance probability estimate of at least 10 percent. During this September 2021 flood event, USGS personnel made over 60 streamflow measurements at streamgages in Pennsylvania using direct and indirect methods. Many of those streamflow measurements were made to verify or improve the accuracy, extent, or development of new stage-streamflow relations at streamgages operated by the USGS. After the floodwaters receded, USGS personnel identified and documented a total of 338 high-water marks in Pennsylvania, noting such things as their general description, location, height above land surface, and quality. Many of these high-water marks were used to create five flood-documentation maps for selected communities in southeastern Pennsylvania that experienced substantial flooding because of the remnants of Hurricane Ida. Digital datasets of the inundated areas, mapped boundaries, and water depth are available (Stuckey and Conlon, 2023).

Pennsylvania↗
USGS1980

Maps showing geology and shallow structure of eastern Rhode Island Sound and Vineyard Sound, Massachusetts

This report presents results of marine studies conducted by the U.S. Geological Survey (USGS) during the summers of 1975 and 1976 in eastern Rhode Island Sound and Vineyard Sound (fig. 1) located off the southeastern coast of Massachusetts. The study was made in cooperation with the Massachusetts Department of Public Works and the New England Division of the U.S. Army Corps of Engineers. It covered an area of the Atlantic Inner Continental Shelf between latitude 41 deg 12' and 41 deg 33'N, and between longitude 70 deg 37' and 71 deg 15'W (see index map). Major objectives included assessment of sand and gravel resources, environmental impact evaluation both of offshore mining of these resources and of offshore disposal of solid waste and dredge spoil material, identification and mapping of the offshore geology, and determination of the geologic history of this part of the Inner Shelf. A total of 670 kilometers (km) of closely spaced high-resolution seismic-reflection profiles, 224 km of side-scan sonar data, and 16 cores totaling 90 meters (m) of recovered sediment, were collected during the investigation. This report is companion to geologic maps published for Cape Cod Bay (Oldale and O'Hara, 1975) and Buzzards Bay, Mass. (Robb and Oldale, 1977).

Massachusetts, Rhode Island↗
USGS2000

Geologic map of the Wildcat Lake 7.5' quadrangle, Kitsap and Mason Counties, Washington

The Wildcat Lake quadrangle lies in the forearc of the Cascadia subduction zone, about 20-km east of the Cascadia accretionary complex exposed in the Olympic Mountains (Tabor and Cady, 1978),and about 100-km west of the axis of the Cascades volcanic arc. The quadrangle lies near the middle of the Puget Lowland, which typically has elevations less than 600 feet (183 m), but on Gold Mountain, in the center of the quadrangle, the elevation rises to 1761 feet (537 m). This anomalously high topography also provides a glimpse of the deeper crust beneath the Lowland. Exposed on Green and Gold Mountains are rocks related to the Coast Range basalt terrane. This terrane consists of Eocene submarine and subaerial tholeiitic basalt of the Crescent Formation, which probably accreted to the continental margin in Eocene time (Snavely and others, 1968). The Coast Range basalt terrane may have originated as an oceanic plateau or by oblique marginal rifting (Babcock and others, 1992), but its subsequent emplacement history is complex (Wells and others, 1984). In southern Oregon, onlapping strata constrain the suturing to have occurred by 50 Ma; but on southern Vancouver Island where the terrane-bounding Leech River fault is exposed, Brandon and Vance (1992) concluded suturing to North America occurred in the broad interval between 42 and 24 Ma. After emplacement of the Coast Range basalt terrane, the Cascadia accretionary complex,exposed in the Olympic Mountains west of the quadrangle,developed by frontal accretion and underplating (e.g., Clowes and others, 1987). The Seattle basin, part of which lies to the north of Green Mountain, also began to develop in late Eocene time due to forced flexural subsidence along the Seattle fault zone (Johnson and others, 1994). Domal uplift of the accretionary complex beneath the Olympic Mountains occurred after approximately 18 million years ago (Brandon and others, 1998). Ice-sheet glaciation during Quaternary time reshaped the topography of the quadrangle, and approximately two-thirds of the map area is covered with Quaternary deposits related to the last glaciation. Geophysical studies and regional mapping indicate the Seattle fault lies north of Green Mountain. This fault produced a large earthquake about 1000 years ago and may pose a significant earthquake hazard (Bucknam and others, 1992; Atwater and Moore, 1992; Karlin and Abella,1992; Schuster and others, 1992; Jacoby and others, 1992). We found no evidence of Holocene faulting in the Wildcat Lake quadrangle. Geologic mapping within and marginal to the quadrangle began with Willis (1898), who described glacial deposits in Puget Sound. Weaver (1937) correlated volcanic rocks in the quadrangle to the Eocene Metchosin Volcanics on Vancouver Island. Sceva (1957), Garling and Moleenar (1965), and Deeter (1978) all focused on mapping and understanding the Quaternary stratigraphy of the Kitsap Peninsula, but they also examined bedrock in the quadrangle. Reeve (1979) was the first to examine the igneous rocks on Green and Gold Mountains in some detail, and Clark (1989) significantly improved Reeve's (1979) mapping. Clark's (1989) mapping was conducted soon after extensive logging on the mountains. A surficial geologic map of the Seattle 1:100,000-scale quadrangle, which includes the Wildcat Lake 1:24,000-scale quadrangle, was published by Yount and others (1993). Yount and Gower (1991) also published a bedrock geologic map of the Seattle quadrangle. Geologic mapping for this report was conducted by Haeussler in the spring and summer of 1998 and in the winter of 1999. We could not substantially improve upon the bedrock mapping of Clark (1989) and thus it is incorporated into this map. Well data in the southeastern corner of the map area also helped to constrain the surficial mapping (Geomatrix Consultants, 1997). In addition, 1995 vintage 1:12,000-scale aerial photographs were used in mapping Quaternary deposits. Geologic time scale is that of Berggeren and others (1995).

Washington↗
USGS1979

Chemical analyses of coal from the Tongue River Member of the Fort Union Formation, Moorhead and southeastern part of the northward extension of the Sheridan coal fields, Powder River and Big Horn counties, Montana

As part of a continuing program by the U.S. Geological Survey to collect and chemically analyze representative samples of U.S. coals, 83 samples were collected from 23 core holes in the Paleocene Tongue River Member of the Fort Union Formation in Big Horn and Powder River counties, Montana. These holes are located in the Montana part of the Powder River coal region, specifically in the western part of the Moorhead coal field and on the eastern margin of the Northward Extension of the Sheridan coal field (fig. 1)

Montana↗
USGS2022

Hydrologic budget of the Harney Basin groundwater system, southeastern Oregon

Groundwater-level declines and limited quantitative knowledge of the groundwater-flow system in the Harney Basin prompted a cooperative study between the U.S. Geological Survey and the Oregon Water Resources Department to evaluate the groundwater-flow system and budget. This report provides a hydrologic budget of the Harney Basin groundwater system that includes separate groundwater budgets for upland and lowland areas to avoid double counting water that recharges in the uplands, discharges to streams and springs in the uplands, flows downstream to the lowlands, and recharges the lowland groundwater system. Lowlands generally represent the conterminous valleys within the center of the basin, including floodplains of the major streams and uplands represent all other areas in the basin. The upland groundwater budget is minimally affected by groundwater development and generally represents the budget of the natural system. In upland areas during 1982–2016, mean-annual recharge totaled 288,000 acre-feet (acre-ft) and mean-annual discharge totaled 239,000 acre-ft, resulting in a net recharge of 49,000 acre-ft. Upland groundwater recharge occurs as infiltration of precipitation and snowmelt and was estimated using the USGS Soil-Water-Balance model calibrated to estimates of runoff, evapotranspiration (ET), base flow, and snow-water equivalent. Groundwater discharge to streams is the predominant discharge mechanism in upland areas and was estimated as 225,000 acre-feet per year (acre-ft/yr) during 1982–2016 using hydrograph separation and summer low-flow estimates in streamgaged watersheds and a linear relation between estimated streamflow and base flow in ungaged watersheds. The remaining upland discharge occurs through springs (14,000 acre-ft/yr) that either emerge downgradient of locations where groundwater discharge to streams was estimated or are routed to irrigated areas. Spring discharge was estimated as a compilation of current and historical measurements. The net upland recharge, which is 17 percent of total upland recharge, ultimately recharges lowland areas as groundwater flow from uplands to lowlands. The lowland groundwater budget for the Harney Basin represents a combination of natural conditions and human activity as more than 99 percent of groundwater development has occurred either inside or within 2 miles of the lowland boundary. In lowland areas during 1982–2016, mean annual groundwater recharge totaled 173,000 acre-ft and groundwater discharge totaled 283,000 acre-ft, indicating discharge exceeded recharge by more than 60 percent. Excluding groundwater pumping, the lowland groundwater budget is more in balance with a mean annual recharge of 165,000 acre-ft and a mean annual discharge of 131,000 acre-ft during 1982–2016. The 23-percent difference between non-pumping recharge and discharge mostly represents the cumulative uncertainty in the estimates of the various groundwater budget components but also likely includes a small reduction in natural groundwater discharge captured by pumping. Lowland groundwater is predominantly recharged by infiltration of surface water (116,000 acre-ft/yr) through streams, floodwater, and irrigation, with a lesser amount as groundwater inflow from uplands and minimal recharge beneath Malheur and Harney Lakes. Recharge from streams and floodwater (natural and irrigation) was estimated using a balance of measured and estimated surface-water inflow to and outflow from lowland areas including streamflow, springflow, and ET where a portion of surface-water inflow to lowland areas is comprised of upland discharge to streams and springs. Groundwater ET (119,000 acre-ft/yr) is the predominant natural discharge mechanism in lowland areas and was estimated as the mean from two remote-sensing based approaches incorporating groundwater ET measurements from other similar basins and 23 years (1987–2015) of Landsat imagery. Discharge of lowland groundwater into Malheur and Harney Lakes is about 700 acre-ft/yr and is represented in groundwater ET estimates. The remaining natural groundwater discharge from lowland areas issues from Sodhouse Spring (8,900 acre-ft/yr) and as groundwater flow to the Malheur River Basin through Virginia Valley (3,100 acre-ft/yr). The relatively large amount of groundwater discharged to springs in Warm Springs Valley (25,000 acre-ft/yr) is accounted for in groundwater ET estimates. Natural groundwater discharge in lowland areas of the Harney Basin has remained relatively constant during the last 80 years based on comparisons with estimates north of Malheur Lake and west of Harney Lake published in the 1930s. Annual net amount of groundwater pumped (pumpage) from the Harney Basin during 2017–18 averaged 144,000 acre-ft. The net value is the difference between pumpage (about 152,000 acre-ft/yr) and reinfiltration of groundwater pumped for irrigation and non-irrigation purposes (about 8,000 acre-ft/yr). Net pumpage was estimated in concurrent studies that compiled groundwater-use data and coupled reported groundwater pumpage data from wells with remote-sensing-based ET estimates from groundwater-irrigated fields. Total pumpage for irrigation has increased from about 54,000 acre-ft/yr during 1991–92 to 145,000 acre-ft/yr during 2017–18. Presently, pumpage is greatest in the lowland region north of Malheur Lake (81,000 acre-ft/yr), with lesser amounts to the north and northwest of Harney Lake (41,000 acre-ft/yr) and to the south and east of Malheur Lake (22,000 acre-ft/yr). During this study, mean annual lowland groundwater discharge (including pumpage) exceeded mean annual recharge, indicating that the lowland hydrologic budget is out of balance. Net groundwater pumpage during 2017–18 is similar to groundwater discharge from all other sources in the lowlands and is four times the imbalance between non-pumping lowland recharge and discharge (34,000 acre-ft/yr). Declining groundwater levels at depth across many parts of the Harney Basin lowlands indicate that pumpage is depleting aquifer storage and is likely capturing a small amount of natural groundwater discharge to springs and ET in some lowland areas. If pumping continues, aquifer storage depletion will continue until the capture rate of natural discharge to springs and ET is equal to the pumping rate. If groundwater development occurs in upland areas and reduces either the streamflow or groundwater inflow to lowland areas, the deficit in the lowland water budget will increase.

Oregon↗
USGS1994

Flood monitoring network in southeastern Louisiana

A flood monitoring network has been established to alert emergency operations personnel and the public about hydrologic conditions in the Amite River Basin. The U.S. Geological Survey (USGS), in cooperation with the Louisiana Office of Emergency Preparedness (LOEP), has installed a real-time data acquisition system to monitor rainfall and river stages in the basin. These data will be transmitted for use by emergency operations personnel to develop flood control and evacuation strategies. The current river stages at selected gaging stations in the basin also will be broadcast by local television and radio stations during a flood. Residents can record the changing river stages on a basin monitoring map, similar to a hurricane tracking map.

Conference Paper↗
USGS2002

Produced water and hydrocarbon releases at the Osage-Skiatook petroleum environmental research sites, Osage County, Oklahoma: Introduction and geologic setting

In February 2001, the USGS started studies of the impacts of produced water and hydrocarbon releases at 2 research sites adjacent to Skiatook Lake in southeastern Osage County near Tulsa, Oklahoma. Both sites are in a dissected area of modest relief underlain by interbedded shale, siltstone, and sandstone. Thicker resistant sandstone units typically form the hill crests. Hillslopes are underlain by shale, siltstone, and thin sandstone beds. Core drilling during February and March of 2002 indicates that the depth of weathering of the bedrock is about 10-25 m on the ridges and 5-6 m in small stream valleys. These sites are located in the Cross Timbers ecosystem area of northeastern Oklahoma. Oak forests cover the hillslopes. Grassslands occur on most ridge crests. Site "A" is an area where produced water and hydrocarbon releases occurred primarily 60-85 years ago. The site is located in section 13, T22N, R10E. The entire site is underlain by 1) a surface layer of eolian sand of varying thickness (maximum observed about 80 cm); 2) colluvium that ranges from large boulders of sandstone to thin, granule-pebble conglomerate; 3) weathered shale, siltstone, and sandstone; and 4) underlying unweathered bedrock. Much of the site appears to have been impacted by early salt-water releases that killed the oak forest, however a few oak trees persist as single trees or clumps of trees within the original kill area. The gently sloping upper part of the site is slightly eroded in places and has been mostly revegetated with grasses, forbs, sumac, and a few trees. The lower, steeper, more heavily salt-impacted portion has been eroded to depths of as much as 2 m. This area drains into the Cedar Creek arm of Skiatook Lake. Oil from two redwood tanks at the top of the site was transported via ditch to two roadside pits at mid-site. Oil spills from pipeline breaks and tank batteries (no longer present) are scattered around the site. Most of the oil is highly weathered however, one pit contains what appears to be relatively fresh asphaltic tank bottom material. Site "B" is located in sections 29 and 32, T22N, R10E. It includes an active production tank battery and adjacent large pit, two injection well sites, one with an adjacent small pit, and an old tank battery. All of these sites are within 45 m of the shoreline of the lake (at normal pool elevation). The pit associated with the active tank battery is within 15 m of the lake. Two small creeks cross the northern and southern parts of the site. The upper part of the site is characterized by a thin surface layer of eolian sand mixed with sandstone-clast colluvium underlain by weathered and unweathered shale whereas the lower part of the site is underlain by 1) a surface layer of eolian sand (20-70 cm thick); 2) colluvial apron and alluvial deposits of varying thickness comprised of sandstone pebbles, cobbles, and boulders with a fine sand matrix; 3) weathered shale; and 4) unweathered bedrock. Three salt scars extend downslope from the active tank battery, the injection well/pit, and the old tank battery to the lake edge. The area underlain by shallow saline ground water is substantially larger than the salt-scarred areas. Dissolved hydrocarbons can be detected in the shallow ground water below the active pit.

Oklahoma↗
USGS2021

Multilevel groundwater monitoring of hydraulic head, water temperature, and chemical constituents in the eastern Snake River Plain aquifer, Idaho National Laboratory, Idaho, 2014–18

Radiochemical and chemical wastewater discharged to infiltration ponds and disposal wells since the early 1950s at the Idaho National Laboratory (INL), southeastern Idaho, has affected the water quality of the eastern Snake River Plain (ESRP) aquifer. In 2006, the U.S. Geological Survey (USGS), in cooperation with the U.S. Department of Energy, added a multilevel well-monitoring network to their ongoing monitoring program to begin describing the vertical movement and distribution of the chemical constituents in the ESRP aquifer. The multilevel monitoring system (MLMS) at the INL has been ongoing since 2006, and this report summarizes data collected during 2014–18 from 11 multilevel monitoring wells. Hydraulic head (head) and groundwater temperature data were collected, including 177 measurements from hydraulically isolated depth intervals from 448.0 to 1,377.6 feet below land surface. One port (port 3) within well USGS 134 was not monitored owing to a valve failure . Note: This is a partial abstract.

Idaho↗
USGS2011

An innovative method for nondestructive analysis of cast iron artifacts at Hopewell Furnace National Historic Site, Pennsylvania

The U.S. Geological Survey (USGS) is conducting research at Hopewell Furnace National Historic Site (fig. 1; see sidebar, page 53) in southeastern Pennsylvania to determine the fate of trace metals, such as arsenic, cobalt, and lead, released into the environment during the iron-smelting process. Arsenic is a carcinogen, cobalt is a suspected carcinogen, and lead can cause severe health problems. Iron ore containing elevated quantities of trace metals was smelted at Hopewell Furnace during its 113 years of operation (1771-1883). The ore used at Hopewell Furnace was obtained from local mines, mainly the Jones and Hopewell mines, which were within 5 miles (8 km) of the furnace. The iron ore deposits were formed during the early Jurassic period about 200 million years ago. The deposits are mineralogically similar and contain abundant magnetite, the chief iron mineral, and accessory minerals enriched in arsenic, cobalt, copper, and other metals.

Pennsylvania↗