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USGS1986

Selected hydrologic data for Salt Lake Valley, Utah, October 1968 to October 1985

This report contains hydrologic data collected in Salt Lake Valley from October 1968 to October 1985. The report area is bounded by the Wasatch Range on the east, the Oquirrh Mountains on the west, the Traverse Mountains on the south, and the boundary between Davis and Salt Lake Counties on the north. Hely and others (1971) defined two aquifers of major importance in the valley the principal aquifer and the shallow aquifer. The principal aquifer is a source of water for public supply and industry, whereas the shallow aquifer in many places contains water that is contaminated and is unsuitable for public supply (Seiler and Waddell, 1984). Most of the data in this report were collected by the U.S. Geological Survey in cooperation with the Utah Department of Natural Resources, Division of Water Rights, Salt Lake County Water Conservancy District, Central Utah Water Conservancy District, Granger-Hunter Improvement District, Magna Water Co. and Improvement District, City of Midvale, Salt Lake City Department of Public Utilities, City of Sandyr City of South Salt Lake, Taylorsville Bennion Improvement District, City of West Jordan, Holladay Water Company, and White City Water Co. Some of the data were published previously by Hely, Mower, and Horr (1967, 1968, and 1969), lorns, Mower, and Horr (1966a and b), Marine and Price (1963), and Seiler and Waddell (1984). The purpose of this report is to provide hydrologic data for use by the general public and by officials who manage water resources and to supplement interpretive reports for the area. Information about wells, water levels in wells, and the chemical and physical properties of ground water is given in tables 1-4, and the well locations are shown on plate 1.

Utah↗

USGS2004

Surficial Geologic Map of the Tanacross B-6 Quadrangle, East-Central Alaska

The Tanacross B-6 1:63,360-scale quadrangle, through which the Alaska Highway runs, is in east-central Alaska about 190 km west of the Yukon border. The surficial geologic mapping in the quadrangle is in support of the 'Geologic Mapping in support of land, resources and hazards issues in Alaska' Project of the USGS National Cooperative Geologic Mapping Program. The Tanacross B-6 quadrangle contains parts of three physiographic provinces: the Alaska Range, the Yukon-Tanana Upland, and the Northway-Tanana Lowland. The high, rugged, glaciated landscape of the eastern Alaska Range dominates the southern and western areas of the map area. Within the map area, about a dozen peaks rise to more than 1,710 m. In contrast, the gently rolling hills of the Yukon-Tanana Upland, in the northeastern map area, only rise to about 975 m. Between the Alaska Range and the Yukon-Tanana Upland lies the Northway-Tanana Lowland, which contains the northwesterly flowing Tanana River. Elevations along the floor of the lowland generally range between 390 and 420 m.The map provides interpretations of the Quaternary surficial deposits and associated geologic hazards in this area of the upper Tanana valley. Because the map area is dominated by various surficial deposits, the map depicts 18 different Quaternary surficial units consisting of artificial fill, alluvial, colluvial, organic, eolian, glaciofluvial, glacial, and periglacial deposits. Deposits shown on this map are generally greater than 1 m thick. The map is accompanied by a text containing unit descriptions incorporating information pertaining to material type, location, associated hazards, resource use (if any), and thickness.

Scientific Investigations Map↗

USGS2006

Surficial Geologic Map of the Tanacross B-4 Quadrangle, East-Central Alaska

The Tanacross B-4 1:63,360-scale quadrangle, through which the Alaska Highway runs, is in east-central Alaska about 100 mi west of the Yukon border. The surficial geologic mapping in the quadrangle is in support of the 'Geologic Mapping in support of land, resources, and hazards issues in Alaska' Project of the USGS National Cooperative Geologic Mapping Program. The Tanacross B-4 quadrangle contains parts of two physiographic provinces, the Yukon-Tanana Upland and the Northway-Tanana Lowland. The gently rolling hills of the Yukon-Tanana Upland, in the northern and eastern map area, rise to about 3,100 ft. The Northway-Tanana Lowland, in the western and southern map area, contains the westerly flowing Tanana River. Elevations along the floor of the lowland generally range between 1,540 and 1,700 ft. The dominant feature within the map is the Tok fan, which occupies about 20 percent of the map area. This large, nearly featureless fan contains a high percentage of volcanic clasts derived from outside the present-day drainage of the Tok River. The map provides interpretations of the Quaternary surficial deposits and associated geologic hazards in this area of the upper Tanana valley. Because the map area is dominated by various surficial deposits, the map depicts 13 different Quaternary surficial units consisting of man-made, alluvial, colluvial, organic, lacustrine, and eolian deposits. Deposits shown on this map are generally greater than 1 m thick. The map is accompanied by a text containing unit descriptions incorporating information pertaining to material type, location, associated hazards, resource use (if any), and thickness.

Scientific Investigations Map↗

USGS2024

Estimating domestic self-supplied water use in Rhode Island, 2014–21

Water withdrawal from private groundwater wells is often unaccounted for in water planning studies, and water from private wells can be a source of exposure to environmental contaminants. The sizes of populations that depend on private wells for domestic water use and the amounts of water that are withdrawn from these wells are generally poorly represented in data collection efforts because of the challenges of locating, metering, or gathering withdrawal information from individual property owners. To address this problem, the U.S. Geological Survey, in cooperation with the Rhode Island Water Resources Board, estimated the volume of water withdrawn from domestic self-supply wells and the populations who use them for the State of Rhode Island at a 30-meter pixel spatial resolution and one-month temporal resolution between July 2014 and June 2021. The number of people reliant on domestic self-supply wells has increased in Rhode Island over the study period; however, the statewide estimate of total water withdrawal has not statistically increased. Withdrawals from private wells are largest in the inland areas of the western part of the State, and the towns of Scituate and Charlestown have the highest estimated withdrawals. Statewide monthly withdrawals ranged from 3.987 million gallons per day in March 2018 to 7.767 million gallons per day in September 2016. The median per capita domestic water use rate was 46.0 gallons per capita per day.

Rhode Island↗

USGS1996

Potential effects of climate change on streamflow, eastern and western slopes of the Sierra Nevada, California and Nevada

Precipitation-runoff models of the East Fork Carson and North Fork American Rivers were developed and calibrated for use in evaluating the sensitivity of streamflow in the north-central Sierra Nevada to climate change. The East Fork Carson River drains part of the rain-shadowed, eastern slope of the Sierra Nevada and is generally higher than the North Fork American River, which drains the wetter, western slope. First, a geographic information system was developed to describe the spatial variability of basin characteristics and to help estimate model parameters. The result was a partitioning of each basin into noncontiguous, but hydrologically uniform, land units. Hydrologic descriptions of these units were developed and the Precipitation- Runoff Modeling System (PRMS) was used to simulate water and energy balances for each unit in response to daily weather conditions. The models were calibrated and verified using historical streamflows over 22-year (Carson River) and 42-year (American River) periods. Simulated annual streamflow errors average plus 10 percent of the observed flow for the East Fork Carson River basin and plus 15 percent for the North Fork American River basin. Interannual variability is well simulated overall, but, at daily scales, wet periods are simulated more accurately than drier periods. The simulated water budgets for the two basins are significantly different in seasonality of streamflow, sublimation, evapotranspiration, and snowmelt. The simulations indicate that differences in snowpack and snowmelt timing can play pervasive roles in determining the sensitivity of water resources to climate change, in terms of both resource availability and amount. The calibrated models were driven by more than 25 hypothetical climate-change scenarios, each 100 years long. The scenarios were synthesized and spatially disaggregated by methods designed to preserve realistic daily, monthly, annual, and spatial statistics. Simulated streamflow timing was not very sensitive to changes in mean precipitation, but was sensitive to changes in mean temperatures. Changes in annual streamflow amounts were amplified reflections of imposed mean precipitation changes, with especially large responses to wetter climates. In contrast, streamflow amount was surprisingly insensitive to mean temperature changes as a result of temporal links between peak snowmelt and the beginning of warm-season evapotranspiration. Comparisons of simulations driven by temporally detailed climate-model changes in which mean temperature changes vary from month to month and simulations in which uniform climate changes were imposed throughout the year indicate that the snowpack accumulates the influences of short-term conditions so that season average climate changes were more important than shorter term changes.

Water-Resources Investigations Report↗

USGS1966

Selected techniques in water resources investigations, 1965

Increasing world activity in water-resources development has created an interest in techniques for conducting investigations in the field. In the United States, the Geological Survey has the responsibility for extensive and intensive hydrologic studies, and the Survey places considerable emphasis on discovering better ways to carry out its responsibility. For many years, the dominant interest in field techniques has been "in house," but the emerging world interest has led to a need for published accounts of this progress. In 1963 the Geological Survey published "Selected Techniques in Water Resources Investigations" (Water-Supply Paper 1669-Z) as part of the series "Contributions to the Hydrology of the United States." The report was so favorably received that successive volumes are planned, of which this is the first. The present report contains 25 papers that represent new ideas being tested or applied in the hydrologic field program of the Geological Survey. These ideas range from a proposed system for monitoring fluvial sediment to how to construct stream-gaging wells from steel oil drums. The original papers have been revised and edited by the compilers, but the ideas presented are those of the authors. The general description of the bubble gage on page 2 has been given by the compilers as supplementary information.

Water Supply Paper↗

USGS2021

Data management and interactive visualizations for the evolving marine biodiversity observation network

Assessing the current state of and predicting change in the ocean’s biological and ecosystem resources requires observations and research to safeguard these valuable public assets. The Marine Biodiversity Observation Network (MBON) partnered with the Global Ocean Observing System Biology and Ecosystems Panel and the Ocean Biodiversity Information System to address these needs through collaboration, data standardization, and data sharing. Here, we describe the generalized MBON data processing flow, which includes several steps to ensure that data are findable, accessible, interoperable, and reusable. By following this flow, data collected and managed by MBON have contributed to our understanding of the Global Ocean Observing System Essential Ocean Variables and demonstrated the value of web-based, interactive tools to explore and better understand environmental change. Although the MBON’s generalized data processing flow is already in practice, work remains in building ontologies for biological concepts, improving processing scripts for data standardization, and speeding up the data collection-to-sharing timeframe.

Oceanography↗

USGS1990

Recent geophysical and geological research in Antarctica related to the assessment of petroleum resources and potential environmental hazards to their development

During the 6-year negotiation of and adoption of the Convention on the Regulation of Antarctic Mineral Resources Activities on June 2, 1988, various countries have increased their attention to the possibility of exploitation of Antarctica's petroleum resources, which are covered by this treaty. However, there are no known petroleum resources in Antarctica, and scientific information is lacking to adequately assess any undiscovered resources or the possible environmental hazards to their development. Scientific research carried out in Antarctica since the International Geophysical Year (1957-1958) has provided a great deal of information on the geological framework of this ice-covered continent and its margin and has found general indications of the types of hazards that must be considered. Antarctica covers a vast area, and likely supergiant oil fields of the type to be exploited would be tiny (e.g., a few tens of kilometers across) in comparison. Any petroleum resources located in Antarctica will be found by applying the knowledge, techniques, and experience gained developing oil fields in other parts of the world and would, therefore, be other examples of general cases; in contrast, the Antarctic environment and its associated hazards must be considered unique.

Book chapter↗

USGS1993

1993 Annual Report: San Francisco estuary regional monitoring program for trace substances

This first annual report of the San Francisco Estuary Regional Monitoring Program contains the results of monitoring measurements made in 1993. Measurements of conventional water quality parameters and trace contaminant concentrations were made at 16 stations throughout the Estuary three times during the year: the wet period (March), during declining Delta outflow (May), and during the dry period (September). Water toxicity tests were conducted at 8 of those stations. Measurements of sediment quality and contaminant concentrations were made at the same 16 stations during the wet and dry sampling periods. Sediment toxicity was measured at 8 of those stations. Transplanted, bagged bivalve bioaccumulation and condition was measured at 11 stations during the wet and dry sampling periods. Water Monitoring. Total or near-total (dissolved + particulate, see text) arsenic, cadmium, selenium, and dissolved (0.45 µm filtered) arsenic, cadmium, copper, nickel, silver, and zinc in water were highest in the South Bay. In general, dissolved metals in water were usually lowest in the Central Bay due to ocean influences. Near-total nickel and total mercury in water were highest in the northern estuary (San Pablo and Suisun Bays). Dissolved chromium and lead were highest at the Sacramento and San Joaquin River confluence stations. Six of the ten dissolved trace metals were highest in March during high runoff. Dissolved and total arsenic, selenium, and near-total cadmium were highest in September. Concentrations of trace organic contaminants are reported for the March sampling period. Total PAHs and PCBs were highest in the South Bay, but PCBs were also high in the Napa River. Dissolved PAHs were highest in the Central Bay, and dissolved PCBs were highest in the Napa River. Total and dissolved pesticides were highest in the Sacramento River and in the Extreme South Bay. Concentrations of trace elements in water (except selenium) were usually closely related with other environmental parameters. Total or near-total metals concentrations in water were most often associated with the amount of particulate material (TSS) in the water. Dissolved concentrations were usually associated with salinity or dissolved organic carbon (DOC) content. Dissolved PAHs were well correlated with TSS, but dissolved and total trace organic contaminants were poorly correlated with other water parameters. Based on deviations from conservative mixing of fresh and salt water, three different patterns of possible sources of metals were identified in 1993. For dissolved chromium and lead, rivers and local runoff appeared to be important sources. For dissolved arsenic, cadmium, copper, and nickel year-round inputs from the South Bay appeared to be important sources. Dissolved mercury, selenium, and zinc were associated with local runoff in the South Bay during the wet period. Dissolved silver did not fit any of these patterns. Although most contaminant concentrations were below water quality objectives, several trace contaminants were above the objectives at some stations. Comparisons to water quality objectives are used as a guide for evaluation of contaminant concentrations, but there are some differences in the way the RMP data are measured and that prescribed for regulatory purposes (see text). Concentrations of 5 metals in water were above EPA or Regional Basin Plan water quality objectives at six stations (see Table 30). Most of these elevated levels occurred at the northern estuary stations. Total PCB concentrations were above EPA human health objectives at all RMP stations. The pesticides chlordane, dieldrin, and DDTs were above the EPA objectives at several RMP stations, particularly at the northern-most, and river confluence stations. Although some of the contaminant concentrations were above water quality objectives, water toxicity tests (96 hour algal growth and 48 hour bivalve larval development tests) did not indicate toxicity (sometimes inconclusive) associated with the water samples collected at any of the RMP stations in 1993. Exposure to Bay San Francisco Estuary Regional Monitoring Program Regional Monitoring Program 1993 Report ii water actually enhanced algal growth at most stations. In addition to the Estuary-wide sampling, the Sacramento and San Joaquin Rivers were sampled upstream from their confluence. Stations in each river were sampled six times over a 6 week period of high flows. In the Sacramento River, seven of the ten dissolved metals measured had concentrations lower than those measured at the river confluence stations. Some metals concentrations in the San Joaquin River were higher, and some were lower than concentrations from the river confluence station. Metals concentrations in the Sacramento River were poorly related to river flow because the station at Rio Vista is under considerable tidal influence. In the San Joaquin River, flows were inversely related to 7 of 10 total metals concentrations. Sediment Monitoring. Concentrations of silver, mercury, and lead in sediment were highest in the South Bay. However, concentrations of most trace metals in sediments were highest in the northern estuary at stations with the finest (silt, clay) sediments. The northern estuary stations with the coarsest (sand, shell) sediments generally had the lowest metals concentrations. There were differences in concentrations of cadmium, lead, and selenium in sediments between the sampling periods, but no consistent trend as to which sampling period had higher values. In September, PAHs and PCBs in sediments were highest in the Central Bay, but pesticides in sediments were highest in the northern estuary and Extreme South Bay. NOAA’s Median Effects Ranges (ERM) for sediments were used as a guide for evaluation of sediment contaminant concentrations. Nickel was the only trace contaminant in sediment above the ERM guidelines, and it was high at all RMP stations. These high levels are probably due to natural, geologic sources. Although sediment contaminant concentrations were below ERMs, sediment toxicity tests (10 day amphipod mortality, and 48 hour bivalve larval development in elutriates) indicated toxicity at all stations tested. Sediment factors that could have caused the toxicity were not investigated. Bivalve Bioaccumulation. Mussels, oysters, and freshwater clams were transplanted to the RMP stations to evaluate bioaccumulation of trace substances. Trace metals were bioaccumulated at nearly all RMP stations. However, arsenic, lead, and mercury did not appear to bioaccumulate. There was generally more bioaccumulation during the dry season than during the wet season. In September, PAHs, PCBs, and pesticides accumulated in all samples. Bioaccumulation of PAHs and pesticides was generally highest at the river confluence stations, and the Napa River. PCBs accumulated most at Redwood Creek. There were substantial differences in the degree of bioaccumulation among the species. Oysters appeared to accumulate higher concentrations of trace metals than the other species, especially copper, which may be a natural phenomenon. There are no established tissue contaminant standards for trace metal and organic contaminants. Therefore, comparisons to Median International Standards (MIS) for human consumption, or U.S. Food and Drug Administration (USFDA) action levels for trace organics are used to evaluate the bioaccumulation results. Concentrations of selenium were higher than MIS guidelines at all stations during the wet season. Other trace metal concentrations were higher than MIS guidelines at various stations during one or the other sampling period. However, none of the bivalves contained concentrations above the USFDA or National Academy of Sciences (NAS) guidelines for trace organic contaminants. The transplanted bivalves survived well at all stations except in the Napa River where less than 35% survived during both sampling seasons. Measures of bivalve condition (dry weight, shell volume) indicated that bivalves deployed in the Central Bay grew significantly, but those at most other stations actually lost weight. Whether these differences were due to natural causes such as salinity or food supply, or to contamination, was not determined. Pilot Studies. Two pilot monitoring studies were conducted in 1993. A pilot study of Estuary hydrography and phytoplankton was conducted by scientists from the U.S. Summary Geological Survey in Menlo Park and U.C. Davis. Water column profiles at up to 37 stations were monitored along a transect of the Estuary run monthly between the South Bay and the Delta. The primary objective of this study was to define physical (salinity, temperature, suspended particulate matter, and light penetration), chemical (dissolved oxygen) and biological (chlorophyll a) characteristics of Estuary water that may influence other chemical and biological reactions. A second objective was to investigate planktonic indicators of ecosystem structure and function. The data collected in 1993 showed the extent and duration of the spring phytoplankton bloom in the South Bay, other localized blooms in the northern estuary, the stratification and mixing associated with the entrapment zone in the northern estuary, and mixing in the Estuary resulting from the high rainfall in 1993. Knowledge of the duration and extent of these natural features of the Estuary provide context for interpretation of the RMP contaminant data collected only 3 times per year. Another pilot study of suspended sediment transport processes was conducted by the USGS in Sacramento. This study used continuous recording sensors at Point San Pablo and the Bay Bridge to measure the amount of suspended sediment in the water at mid-depth and near the bottom, as well as tide height. The objectives of this study were to estimate which factors determine suspended solids concentrations in the Central Bay and to collect time series of suspended solids that are appropriate for continuous monitoring of suspended solids and for calibration and validation of numerical models. The investigators determined that spring tides accounted for most of the variation in suspended solids concentrations at the stations monitored, not runoff from the Sacramento or San Joaquin Rivers, or semidiurnal and diurnal tides. Comparisons were also made between measurements made by the continuous recordings and the RMP samples collected during the regular monitoring cruises. The different ways of measuring TSS were generally comparable, however only 3 measurements per year as made by the RMP could not provide the information of TSS variation actually occurring in the Estuary. This information is important because as shown by the RMP data, total contaminant concentrations in Estuary water is largely dependent on the TSS in the water. This implies that the RMP measurements alone cannot determine accurately the range of contaminant concentrations without better characterizing the dynamics of TSS. The RMP Pilot Studies are important to the developing RMP because they will help put RMP measurements into the perspective of Estuary processes and mechanisms at other time scales. The studies can relate those processes to the RMP measurements and will facilitate revision of sampling design and interpretation. Summaries of other monitoring activities pertinent to regional monitoring are also included in the Report: a description of the Regional Board’s Bay Protection Studies, the Sacramento Coordinated Monitoring Program, and a wetlands monitoring plan are included.

California↗

USGS1988

Extracting topographic structure from digital elevation data for geographic information-system analysis

Software tools have been developed at the U.S. Geological Survey's EROS Data Center to extract topographic structure and to delineate watersheds and overland flow paths from digital elevation models. The tools are specialpurpose FORTRAN programs interfaced with general-purpose raster and vector spatial analysis and relational data base management packages. The first phase of analysis is a conditioning phase that generates three data sets: the original OEM with depressions filled, a data set indicating the flow direction for each cell, and a flow accumulation data set in which each cell receives a value equal to the total number of cells that drain to it. The original OEM and these three derivative data sets can then be processed in a variety of ways to optionally delineate drainage networks, overland paths, watersheds for userspecified locations, sub-watersheds for the major tributaries of a drainage network, or pour point linkages between watersheds. The computer-generated drainage lines and watershed polygons and the pour point linkage information can be transferred to vector-based geographic information systems for futher analysis. Comparisons between these computergenerated features and their manually delineated counterparts generally show close agreement, indicating that these software tools will save analyst time spent in manual interpretation and digitizing.

Photogrammetric Engineering and Remote Sensing↗

USGS2013

Golden eagle population trends in the western United States: 1968-2010

In 2009, the United States Fish and Wildlife Service promulgated permit regulations for the unintentional lethal take (anthropogenic mortality) and disturbance of golden eagles (Aquila chrysaetos). Accurate population trend and size information for golden eagles are needed so agency biologists can make informed decisions when eagle take permits are requested. To address this need with available data, we used a log-linear hierarchical model to average data from a late-summer aerial-line-transect distance-sampling survey (WGES) of golden eagles in the United States portions of Bird Conservation Region (BCR) 9 (Great Basin), BCR 10 (Northern Rockies), BCR 16 (Southern Rockies/Colorado Plateau), and BCR 17 (Badlands and Prairies) from 2006 to 2010 with late-spring, early summer Breeding Bird Survey (BBS) data for the same BCRs and years to estimate summer golden eagle population size and trends in these BCRs. We used the ratio of the density estimates from the WGES to the BBS index to calculate a BCR-specific adjustment factor that scaled the BBS index (i.e., birds per route) to a density estimate. Our results indicated golden eagle populations were generally stable from 2006 to 2010 in the 4 BCRs, with an estimated average rate of population change of −0.41% (95% credible interval [CI]: −4.17% to 3.40%) per year. For the 4 BCRs and years, we estimated annual golden eagle population size to range from 28,220 (95% CI: 23,250–35,110) in 2007 to 26,490 (95% CI: 21,760–32,680) in 2008. We found a general correspondence in trends between WGES and BBS data for these 4 BCRs, which suggested BBS data were providing useful trend information. We used the overall adjustment factor calculated from the 4 BCRs and years to scale BBS golden eagle counts from 1968 to 2005 for the 4 BCRs and for 1968 to 2010 for the 8 other BCRs (without WGES data) to estimate golden eagle population size and trends across the western United States for the period 1968 to 2010. In general, we noted slightly declining trends in southern BCRs and slightly increasing trends in northern BCRs. However, we estimated the average rate of golden eagle population change across all 12 BCRs for the period 1968–2010 as +0.40% per year (95% CI = −0.27% to 1.00%), suggesting a stable population. We also estimated the average rate of population change for the period 1990–2010 was +0.5% per year (95% CI = −0.33% to 1.3%). Our annual estimates of population size for the most recent decade range from 31,370 (95% CI: 25,450–39,310) in 2004 to 33,460 (95% CI: 27,380–41,710) in 2007. Our results clarify that golden eagles are not declining widely in the western United States. © 2013 The Wildlife Society.

Arizona;California;Colorado;Idaho;Iowa;Kansas;Minn↗

USGS2013

Descriptive and geoenvironmental model for Co-Cu-Au deposits in metasedimentary rocks

Introduction This report is a revised model for a specific type of cobalt-copper-gold (Co-Cu-Au) deposit that will be evaluated in the next U.S. Geological Survey (USGS) assessment of undiscovered mineral resources in the United States (see Ferrero and others, 2012). Emphasis is on providing an up-to-date deposit model that includes both geologic and geoenvironmental aspects. The new model presented here supersedes previous USGS models by Earhart (1986) and Evans and others (1995), which are based solely on deposits in the Blackbird mining district of central Idaho. This report is a broader synthesis of information on 19 Co-Cu-Au deposits occurring in predominantly metasedimentary successions worldwide (table 1–1) that generally share common geologic, mineralogical, and geochemical features; preliminary summary versions were presented in Slack and others (2010) and Slack and others (2011), which are superseded by this report. As defined herein, the individual Co-Cu-Au deposits are located more than 500 meters from similar deposits and contain 0.1 percent or more by weight of Co in ore or mineralized rock; some deposits included in the database lack reported average Co grades, but they contain high Co concentrations, at least locally. Most of the deposits also have high As contents, present in Co arsenide and sulfarsenide minerals. Type examples of the Co-Cu-Au deposits are those in the Blackbird district, Skuterud in Norway, and Kouvervarra and Juomasuo in Finland. Some deposits in the database have low grades for Cu (for example, NICO in Canada) or Au (for example, Lemmonlampi in Finland), but these deposits are included because their geological, mineralogical, and alteration features are similar to those of the type examples. Several deposits included in the model are partly hosted by metavolcanic or metaigneous rocks (including granite), but regionally these deposits are within metasedimentary successions; no deposits are wholly within granite or other plutonic igneous intrusions. Despite having a lower average Co grade, the Mt. Cobalt deposit in Australia is included here because it has past Co production from higher-grade ore zones (Nisbet and others, 1983). The Black Pine deposit in the Idaho cobalt belt is included because it contains mineable Co- and Au-rich lenses within Cu-rich mineralized zones (Formation Metals, Inc., 2012). Six deposits that lack data for average Co grades are also included because each reportedly contains abundant Co (>0.1 weight percent Co), at least locally. Many of the deposits are noteworthy as possible resources of Ag, Bi, W, Ni, Y, REE, and (or) U. Detailed data on the deposits listed in table 1–1, including references, are available in appendix 1. Significantly, the grouping in this report of Co-Cu-Au deposits in metasedimentary rocks into a single model includes deposits that other workers have previously classified in different ways. For background information, a global overview of different types of Co deposits worldwide is given in Smith (2001). Additional geologically and compositionally similar deposits are known, but have average Co grades less than 0.1 percent. Most of these deposits contain cobalt-rich pyrite and lack appreciable amounts of distinct Co sulfide and (or) sulfarsenide minerals. Such deposits are not discussed in detail in the following sections, but these deposits may be relevant to the descriptive and genetic models presented below. Examples include the Scadding Au-Co-Cu deposit in Ontario, Canada; the Vähäjoki Co-Cu-Au deposit in Finland; the Tuolugou Co-Au deposit in Qinghai Province, China; the Lala Co-Cu-UREE deposit in Sichuan Province, China; the Guelb Moghrein Cu-Au-Co deposit in Mauritania; and the Great Australia Co-Cu, Greenmount Cu-Au-Co, and Monakoff Cu-Au-Co-UAg deposits in Queensland, Australia. Detailed information on these deposits is presented in appendix 2.

Scientific Investigations Report↗

USGS1977

Tactical approach for determining impact of energy development on wildlife in Wyoming: special report number 1

The U.S. Fish and Wildlife Service, within the Department of Interior, is responsible for providing national leadership in the management and protection of the nation's fish and wildlife resources, their habitat, and environment. Specifically, the Office of Biological Services obtains and assimilates biological and environmental data and identifies additional informational needs and means necessary to provide biological input into major natural resource decisions. The Wyoming Coal Coordinator for the U.S Fish and Wildlife Service is assigned the duty of becoming attuned to the ramifications of energy development within the State and its potential impact upon wildlife. In order for the Coal Coordinator to fulfill his obligations in becoming an "energy expert" for the Fish and Wildlife Service in Wyoming, it will be necessary for him to develop a means of obtaining an overview of the energy development situation. Similarly, in order for him to identify those area of critical concern to wildlife resources, it will be necessary that he determine or predict where energy development will occur, the nature of this development, and the cumulative effects of energy development upon wildlife. Likewise, in order to identify where wildlife data gaps occur and to determine future wildlife information needs, it will be necessary for him to compile and synthesize relevant existing data resources. It therefore becomes apparent that a need exists for him to gather and interpret pertinent information in a systematic way to meet these ends. The following is an account of the tactical number in which the Wyoming Coal Coordinator intends to approach the duties outlined above the rationale to be followed in meeting these needs. First, a general discussion on assessing impacts on wildlife is provided to form a basis for obtaining an overview. Secondly, a series of reports which will be generated to summarize existing information and to help identify potential problem areas is outlined. These reports will be further utilized to determine wildlife data gaps and future information needs related to wildlife and future energy development.

Wyoming↗

USGS2024

Detecting avalanche path ground cover and vegetation change across multiple scales through time using remote sensing tools

Large-magnitude avalanches often alter vegetation composition, avalanche path dimensions, and subsequent avalanche return periods. Understanding temporal changes in individual avalanche path trimlines, runout zones, and geomorphic characteristics helps forecasters, planners, and engineers estimate potential avalanche destructive size and impact on infrastructure or settlements in the runout zone. Understanding these changes on a large scale also provides information on post-cycle avalanche distribution. Here, we use remote sensing platforms and change detection techniques to examine vegetation change in avalanche paths in Montana and Colorado. In northwest Montana, we implemented a novel approach using lidar, aerial imagery, and a random forest model to classify imagery-observed vegetation within avalanche paths. We calculated spatially explicit avalanche return periods using a physically based spatial interpolation method and characterized the vegetation within those return period zones. In Colorado, we investigated changes in avalanche path vegetation characteristics prior to and after a widespread large-magnitude avalanche cycle. The highest frequency of avalanche return periods was broadly characterized by grassland and shrubland, but topography greatly influences vegetation classes and return periods. Furthermore, statistically significant differences in lidar-derived vegetation canopy height exist between categorical return periods. We used optical sensors from satellite imagery to analyze changes in Normalized Difference Vegetation Index (NDVI) to calculate ground cover change over time. NDVI, a measure of near-infrared and red bands within the imagery, allowed us to distinguish between green vegetation (e.g., trees and shrubs) and non-vegetated ground cover (e.g., dead and downed trees, rocks, and dirt) within avalanche paths. For this study, we calculated changes in NDVI values by comparing imagery from 2018 to imagery from 2019 after a widespread large magnitude avalanche cycle occurred in March 2019 in Colorado, United States. We applied a filtering process to reduce error, classified NDVI change based on the value distribution, and then calculated area change of all areas within each avalanche path. We completed this process for 1633 avalanche paths throughout Colorado. We found that using NDVI difference values pre- and post-avalanche cycle allowed us to identify ground cover change in avalanche paths throughout Colorado. These changes span from a slight expansion of existing avalanche paths to substantial landscape disturbance. For example, a size D5 avalanche caused severe ground cover change in 18% of one single path near Aspen, Colorado. This suggests that large magnitude avalanches can redefine avalanche path dimensions and could impact subsequent avalanche size and frequency. Using NDVI from satellite imagery is a simple way to detect ground cover changes in avalanche paths on a large scale or in remote areas. In general, remote sensing products to detect and examine vegetation and ground cover change in avalanche paths can help inform avalanche distribution and benefit planning efforts.

Montana↗

USGS2023

Landslide initiation thresholds in data-sparse regions: Application to landslide early warning criteria in Sitka, Alaska, USA

Probabilistic models to inform landslide early warning systems often rely on rainfall totals observed during past events with landslides. However, these models are generally developed for broad regions using large catalogs, with dozens, hundreds, or even thousands of landslide occurrences. This study evaluates strategies for training landslide forecasting models with a scanty record of landslide-triggering events, which is a typical limitation in remote, sparsely populated regions. We evaluate 136 statistical models trained on a precipitation dataset with five landslide-triggering precipitation events recorded near Sitka, Alaska, USA, as well as > 6000 d of non-triggering rainfall (2002–2020). We also conduct extensive statistical evaluation for three primary purposes: (1) to select the best-fitting models, (2) to evaluate performance of the preferred models, and (3) to select and evaluate warning thresholds. We use Akaike, Bayesian, and leave-one-out information criteria to compare the 136 models, which are trained on different cumulative precipitation variables at time intervals ranging from 1 h to 2 weeks, using both frequentist and Bayesian methods to estimate the daily probability and intensity of potential landslide occurrence (logistic regression and Poisson regression). We evaluate the best-fit models using leave-one-out validation as well as by testing a subset of the data. Despite this sparse landslide inventory, we find that probabilistic models can effectively distinguish days with landslides from days without slide activity. Our statistical analyses show that 3 h precipitation totals are the best predictor of elevated landslide hazard, and adding antecedent precipitation (days to weeks) did not improve model performance. This relatively short timescale of precipitation combined with the limited role of antecedent conditions likely reflects the rapid draining of porous colluvial soils on the very steep hillslopes around Sitka. Although frequentist and Bayesian inferences produce similar estimates of landslide hazard, they do have different implications for use and interpretation: frequentist models are familiar and easy to implement, but Bayesian models capture the rare-events problem more explicitly and allow for better understanding of parameter uncertainty given the available data. We use the resulting estimates of daily landslide probability to establish two decision boundaries that define three levels of warning. With these decision boundaries, the frequentist logistic regression model incorporates National Weather Service quantitative precipitation forecasts into a real-time landslide early warning “dashboard” system ( https://sitkalandslide.org/ , last access: 9 October 2023). This dashboard provides accessible and data-driven situational awareness for community members and emergency managers.

Alaska↗

USGS2007

Factors affecting herbicide yields in the Chesapeake Bay watershed, June 1994

Median concentrations and instantaneous yields of alachlor, metolachlor, atrazine, cyanazine, and simazine were generally highest at sites in the Lower Susquehanna River Basin and in agricultural subbasins. Instantaneous herbicide yields are related to land use, hydrogeologic setting, streamflow yield, and agricultural row cropping practices. The significance of these relations may be affected by the interdependence of the factors. The percentage of basin area planted in corn is the most influential factor in the prediction of herbicide yield. Instantaneous yields of all five herbicides measured in June 1994 related poorly to averaged 199094 herbicide use. Annually averaged herbicide-use data are too general to use as a predictor for short-term herbicide yields. An evaluation of factors affecting herbicide yields could be refined with more-current land use and land cover information and a more accurate estimate of the percentage of basin area planted in corn. Factors related to herbicide yields can be used to predict herbicide yields in other basins within the Chesapeake Bay watershed and to develop an estimate of herbicide loads to Chesapeake Bay.Median concentrations and instantaneous yields of alachlor, metolachlor, atrazine, cyanazine, and simazine were generally highest at sites in the Lower Susquehanna River Basin and in agricultural subbasins. Instantaneous herbicide yields are related to land use, hydrogeologic setting, streamflow yield, and agricultural row cropping practices. The significance of these relations may be affected by the interdependence of the factors. The percentage of basin area planted in corn is the most influential factor in the prediction of herbicide yield. Instantaneous yields of all five herbicides measured in June 1994 related poorly to averaged 1990-94 herbicide use. Annually averaged herbicide-use data are too general to use as a predictor for short-term herbicide yields. An evaluation of factors affecting herbicide yields could be refined with more-current land use and land cover information and a more accurate estimate of the percentage of basin area planted in corn. Factors related to herbicide yields can be used to predict herbicide yields in other basins within the Chesapeake Bay watershed and to develop an estimate of herbicide loads to Chesapeake Bay.

Water Resources Bulletin↗

USGS1992

Resistance of young wolf pups to inclement weather

Based on information about young dog ( Canis familiaris ) pups, it was thought that wolf ( Canis lupus ) pups 0-2 weeks of age do not thermoregulate well. This problem, plus the relative immobility of young pups, was thought to explain why pups generally remain inside dens until about 3 weeks of age, and pups younger than 3-weeks-old were thought to be highly vulnerable to loss from exposure. this report details more information about the tolerance of young wolf pups to exposure.

Research Information Bulletin↗

USGS2002

Porphyry copper deposits of the world: Database, maps, and preliminary analysis

Mineral deposit models are important in exploration planning and quantitative resource assessments for two reasons: (1) grades and tonnages among deposit types are significantly different, and (2) many types occur in different geologic settings that can be identified from geologic maps. Mineral deposit models are the keystone in combining the diverse geoscience information on geology, mineral occurrences, geophysics, and geochemistry used in resource assessments and mineral exploration. Far too few thoroughly explored mineral deposits are available in most local areas for reliable identification of the important geoscience variables or for robust estimation of undiscovered deposits—thus we need mineral-deposit models. Globally based deposit models, such as those presented here, allow recognition of important features because the global models demonstrate how common different features are. Well-designed and -constructed deposit models allow geologists to know from observed geologic environments the possible mineral deposit types that might exist, and allow economists to determine the possible economic viability of these resources in the region. Thus, mineral deposit models play the central role in transforming geoscience information to a form useful to policy makers. The foundation of mineral deposit models is information about known deposits—the purpose of this publication is to make this kind of information available in digital form for a group of porphyry copper deposits. This publication contains a computer file of information on porphyry copper deposits around the world. It also presents new grade and tonnage models for three subtypes of porphyry copper deposits, maps showing locations and general ages of these deposits, and a preliminary analysis with a number of figures summarizing many of the properties of these porphyry-style deposits. These summaries can be considered a new, quantified, form of most parts of descriptive models such as those in Cox and Singer (1986). The value of this information and analyses depends critically on the consistent manner of data gathering. For this reason, we first discuss the rules used in this compilation. Next the fields of the data file are considered. Finally, we discuss some of the things that can be done with the data.

Open-File Report↗