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USGS2019

Detailed Lithologic Logs from Auger Holes in southern Charleston County, southwestern Dorchester County, and eastern Colleton County, South Carolina

The lithologic logs described in this open-file report are from holes augered in the South Carolina Low Country in parts of Charleston, Dorchester, and Colleton Counties from 1998 through 2010. Lithologic units described here include not only surficial Pleistocene units but also subsurface stratigraphic units ranging as far back in age as late Eocene. This region comprises the southernmost and westernmost portions of the area included in the 1:100,000 Charleston region geologic map, which lies east of 80°30′ west and south of 33°15′ north. Logs of the remainder of that map area were published prior to the release of that map. The present report completes the lithologic log record from which the 1:100,000 Charleston region geologic map largely was compiled.

South Carolina↗

USGS2021

Genetic diversity is considered important but interpreted narrowly in country reports to the Convention on Biological Diversity: Current actions and indicators are insufficient

International agreements such as the Convention on Biological Diversity (CBD) have committed to conserve, and sustainably and equitably use, biodiversity. The CBD is a vital instrument for global conservation because it guides 195 countries and the European Union in setting priorities and allocating resources, and requires regular reporting on progress. However, the CBD and similar policy agreements have often neglected genetic diversity. This is a critical gap because genetic diversity underlies adaptation to environmental change and ecosystem resilience. Here we aim to inform future policy, monitoring, and reporting efforts focused on limiting biodiversity loss by conducting the largest yet evaluation of how Parties to the CBD report on genetic diversity. A large, globally representative sample of 114 CBD National Reports was examined to assess reported actions, progress, values and indicators related to genetic diversity. Although the importance of genetic diversity is recognized by most Parties to the CBD, genetic diversity targets mainly addressed variation within crops and livestock (a small fraction of all species). Reported actions to conserve genetic diversity primarily concerned ex situ facilities and legislation, rather than monitoring and in situ intervention. The most commonly reported status indicators are not well correlated to maintaining genetic diversity. Lastly, few reports mentioned genetic monitoring using DNA data, indigenous use and knowledge of genetic diversity, or development of strategies to conserve genetic diversity. We make several recommendations for the post-2020 CBD Biodiversity Framework, and similar efforts such as IPBES, to improve awareness, assessment, and monitoring of genetic diversity, and facilitate consistent and complete reporting in the future.

Biological Conservation↗

USGS1901

Twenty-First Annual report of the Director of the United States Geological Survey, 1899-1900: Part VII - Texas

Area treated. —The Black and Grand prairies of Texas and southern Indian Territory comprise about 50,000 square miles (see Pl. LXV, in pocket)—an area equal to that of fifty of the quadrangles mapped and described by the United States Geological Survey in its Geologic Atlas of the United States. The accompanying general geologic map (Pl. LXVI, in pocket) is a condensed presentation of the geology usually shown on that number of atlas sheets as published in folio form. Most of these quadrangles have been studied by the writer and his former assistants. Sources of data. —An entirely satisfactory presentation of these results is still impossible by reason of the lack of adequate maps. The topographic maps of the United States Geological Survey, which cover 24 of the 50 units of area, were made in the earlier years of the Survey and with a contour interval insufficient for the expression of the geology. For the remaining portion of the area it was necessary to use as a base the Land Office maps of the State of Texas. The conclusions herein presented, often condensed in a short paragraph, are founded upon a large amount of paleontologic, stratigraphic, and topographic data. The results, so far as they refer to the Black and Grand prairies, are the outcome of studies made by the writer since 1882, sometimes independently, sometimes with the assistance of the United States Geological Survey, and during two years in connection with the Texas Geological Survey. In times past he has been assisted in this work by his former students, C. C. McCulloch, now captain, U. S. A.; Messrs. Wilson T. Davidson and L. T. Dashiel; Mr. Joseph A. Taff, now of the United States Geological Survey; Dr. J. W. Stone, Mr. N. F. Drake, and Mr. G. H. Ragsdale. Inasmuch as the details which these gentlemem worked out were problems of the writer's suggestion, he has incorporated them into this paper, and here acknowledges indebtedness therefor. Upon the writer's retirement from the Texas Survey, Mr. Taff continued the work of mapping the region. He published two reports, which have been freely used and which have been of great assistance in the preparation of this paper. Importance of paleontology. —In addition to the collection of the data which appear in the text and illustrations, much paleontologic research has been necessary in order to classify the formations. Paleontology is the most reliable guide in determining the position of any bed in the geologic series with a view to ascertaining the depth, from any particular portion of the surface, of the underground waters in the Cretaceous regions of Texas. If a few species of fossils, such as can be found in any locality, be sent to one familiar with the sequence of the beds, he can predict within a few feet the depth below the surface of any particular water-bearing stratum in the series. It was a labor of years to disentangle the preexisting confusion concerning the occurrence and succession of these fossils and their bearings upon the determination and definition of the strata. Their further consideration has been left to Mr. T. W. Stanton, who, it is presumed, will make final publication of the descriptions and the scientific results. This is not a final and complete report. Detailed field work is desirable in many localities. Chemical analyses of water and illustrations of typical scenery should be more complete, but these were not obtainable with the means and time at the writer's disposal. When appreciation of geologic investigation shall have been awakened in Texas and the region under discussion shall have been studied more closely by resident students, in the manner now common in other parts of the United States, the data here presented will be largely increased and refined, and the conclusions will doubtless be correspondingly amended and rectified.

Texas↗

USGS1987

Water-resources activities of the U.S. Geological Survey in South Dakota; fiscal years 1986-87

In South Dakota, the first collection of streamflow data by the U.S. Geological Survey (USGS) was in 1903. Despite its early beginning, it was not until October 16, 1944, that the Bismarck District, comprising the states of North Dakota and South Dakota , was created to assess the water resources of the two states. The next major increase in collection of surface water records occurred during the mid-1940 's as a result of the Pick-Sloan Plan for Missouri Basin development. Since 1944, about 98 water resources studies have been made in South Dakota. These range from reconnaissance-type studies of counties and Indian reservations to research on small basin runoff and toxic wastes, the quality of water in lakes, the use of remote sensing for defining aquifers, and studies using digital models to describe the groundwater regimen and surface water hydraulics such as those currently underway in the James River basin and the Big Sioux River basin. During the past 20 years, 140 formal reports describing the studies and results of investigations have been prepared to inform the public and the scientific community. The location of surface water stations and observation wells in bedrock are tabulated. Brief (1 page) descriptions of current water resources projects in South Dakota include information on the location, purpose, period of performance, cooperating agencies, project leader, and completed reports. (Lantz-PTT)

Open-File Report↗

USGS1952

The industrial utility of public water supplies in the east south central states, 1952

The location of industrial plants is dependent on an ample water supply of suitable quality. Information relating to the chemical characteristics of the water supplies is not only essential to the location of many plants but also is an aid in the manufacture and distribution of many commodities. Public water supplies are utilized extensively as a source of supply for many industrial plants, used either as delivered for domestic consumption or with further treatment if necessary to meet specific needs of the plant, such as water for processing, cooling, and steam generation. The industrial use of water in the United States in 1950 was estimated to be more than 75 billion gallons per day from private sources. In addition, about 6 billion gallons per day was estimated to be taken from public water supplies. U. S. Geological Survey Water-Supply Paper 658, "The industrial utility of public water supplies in the United States, 1932" contains information pertaining to the public water supplies of 670 of the larger cities throughout the United States. This report, which is still in print and being distributed, has filled an important need in the field of water-supply engineering. The demand for more up-to-date information and more extended coverage has led to studies by the Geological Survey for revision of the information contained in the 1932 report. The revised report, which will include data pertaining to public water supplies of more than 1,200 cities in the United States, will eventually be published as a Geological Survey Water-Supply Paper. However, in order that the information might be available at the earliest possible time, nine preliminary reports are being issued which give data on the larger cities in each state. These nine reports are being released as Geological Survey Circulars, each covering a group of states as delineated by the Bureau of Census in taking the census of the population of the country. (See fig. 1). The reports give descriptive information and analytical data for approximately three-fourths of the cities that will be included in the final report for each of the states. This circular is the first of the series and includes data for the States of Alabama, Kentucky, Mississippi, and Tennessee. (See fig. 1). The report gives the population (1950) of the city, population supplied, ownership, sources and treatment of supplies, capacity of treatment plants, storage facilities for both raw and finished waters, and chemical analyses of the water, for 19 cities in Alabama, 16 in Kentucky, 17 in Mississippi, and 15 in Tennessee. The data for each city are essentially the same as will appear in the complete report for the whole country.

Alabama;Kentucky;Mississippi;Tennessee↗

USGS1952

The industrial utility of public water supplies in the Mountain States, 1952

The location of industrial plants is dependent on an ample water supply of suitable quality. Information relating to the chemical characteristics of the water supplies is not only essential to the location of many plants but also is an aid in the manufacture and distribution of many commodities. Public water supplies are utilized extensively as a source of supply for many industrial plants, used either as delivered for domestic consumption or with further treatment if necessary to meet specific needs of the plant, such as water· for processing, cooling, and steam generation. The industrial use of water in the United States in 1950 was estimated to be more than 75 billion gallons per day from private sources. In addition, about 6 billion gallons per day was estimated to be taken from public water supplies. U.S. Geological Survey Water-Supply Paper 658, "The industrial utility of public water supplies in the United States, 1932" contains information pertaining to the public water supplies of 670 of the larger cities throughout the United States. This report, which is still in print and being distributed, has filled an important need in the field of water-supply engineering. The demand for more up-to-date information and more extended coverage has led to studies by the Geological Survey for revision of the information contained in the 1932 report. The revised report, which will include data pertaining to public water supplies of more than 1, 200 cities in the United States, will eventually be published as a Geological Survey Water-Supply Paper. However, in order that the information might be available at the earliest possible time, nine preliminary reports are being issued which give data on the ·larger cities in each state. These nine reports are being released as Geological Survey Circulars, each covering a group of states as delineated by the Bureau of Census in taking the census of the population of the country. (See fig. 1). The reports give descriptive information and analytical data for approximately three-fourths of the cities that will be included in the final report for each of the states. This circular is the second of the series and includes data for the States of Arizona, Colorado, Idaho, Montana, Nevada, New Mexico, Utah, and Wyoming. The report gives the population (1950) of the city, population supplied, ownership, sources and treatment of supplies, capacity of treatment plants, storage facilities for both raw and finished waters, and chemical analyses of the water for 11 cities in Arizona, 8 in Colorado, 12 in Idaho, 9 in Montana, 8 in Nevada, 9 in New Mexico, 9 in Utah, and 8 in Wyoming. The data for each city are essentially the same as will appear in the complete report for the whole country.

Arizona, Colorado, Idaho, Montana, Nevada, New Mex↗

USGS2005

Studies by the U.S. Geological Survey in Alaska, 2004

The collection of six papers that follow continues the series of U.S. Geological Survey (USGS) investigative reports in Alaska under the broad umbrella of the geologic sciences. This series represents new and sometimes-preliminary findings that are of interest to Earth scientists in academia, government, and industry; to land and resource managers; and to the general public. The reports presented in Studies by the U.S. Geological Survey in Alaska cover a broad spectrum of topics from various parts of the State, serving to emphasize the diversity of USGS efforts to meet the Nation's needs for Earth-science information in Alaska. This professional paper is the first 'online only' version of Studies by the U.S. Geological Survey in Alaska, reflecting the current trend toward disseminating research results on the World Wide Web with rapid posting of completed reports.

Professional Paper↗

USGS2006

Studies by the U.S. Geological Survey in Alaska, 2005

Summary The collection of papers that follows continues the series of U.S. Geological Survey (USGS) investigative reports in Alaska under the broad umbrella of the geologic sciences. This series represents new and sometimes-preliminary findings that are of interest to Earth scientists in academia, government, and industry; to land and resource managers; and to the general public. The reports presented in Studies by the U.S. Geological Survey in Alaska cover a broad spectrum of topics from various parts of the State, serving to emphasize the diversity of USGS efforts to meet the Nation’s needs for Earth-science information in Alaska. This professional paper is one of a series of “online only” versions of Studies by the U.S. Geological Survey in Alaska , reflecting the current trend toward disseminating research results on the World Wide Web with rapid posting of completed reports.

Alaska↗

USGS2009

Studies by the U.S. Geological Survey in Alaska, 2007

The collection of papers that follow continues the series of U.S. Geological Survey (USGS) investigative reports in Alaska under the broad umbrella of the geologic sciences. This series represents new and sometimes-preliminary findings that are of interest to Earth scientists in academia, government, and industry; to land and resource managers; and to the general public. The reports presented in Studies by the U.S. Geological Survey in Alaska cover a broad spectrum of topics from various parts of the State, serving to emphasize the diversity of USGS efforts to meet the Nation's needs for Earth-science information in Alaska. This professional paper is one of a series of 'online only' versions of Studies by the U.S. Geological Survey in Alaska, reflecting the current trend toward disseminating research results on the World Wide Web with rapid posting of completed reports.

Professional Paper↗

USGS2010

Studies by the U.S. Geological Survey in Alaska, 2008-2009

Professional Paper↗

USGS2011

Studies by the U.S. Geological Survey in Alaska, 2010

The collection of papers that follows continues the series of U.S. Geological Survey (USGS) investigative reports in Alaska under the broad umbrella of the geologic sciences. This series represents new and sometimes-preliminary findings that are of interest to Earth scientists in academia, government, and industry; to land and resource managers; and to the general public. The reports presented in Studies by the U.S. Geological Survey in Alaska cover a broad spectrum of topics from various parts of the State, serving to emphasize the diversity of USGS efforts to meet the Nation’s needs for Earth-science information in Alaska. This professional paper is one of a series of “online only” versions of Studies by the U.S. Geological Survey in Alaska , reflecting the current trend toward disseminating research results on the World Wide Web with rapid posting of completed reports.

Alaska↗

USGS2012

Studies by the U.S. Geological Survey in Alaska, 2011

The collection of papers that follow continues the series of U.S. Geological Survey (USGS) investigative reports in Alaska under the broad umbrella of the geologic sciences. This series represents new and sometimes-preliminary findings that are of interest to Earth scientists in academia, government, and industry; to land and resource managers; and to the general public. The reports presented in Studies by the U.S. Geological Survey in Alaska cover a broad spectrum of topics from various parts of the State, serving to emphasize the diversity of USGS efforts to meet the Nation's needs for Earth-science information in Alaska. This professional paper is one of a series of "online only" versions of Studies by the U.S. Geological Survey in Alaska , reflecting the current trend toward disseminating research results on the World Wide Web with rapid posting of completed reports.

Alaska↗

USGS2012

Migrated hydrocarbons in exposure of Maastrichtian nonmarine strata near Saddle Mountain, lower Cook Inlet, Alaska

Magoon and others (1980) described an 83-meter- (272-foot-) thick succession of Maastrichtian (Upper Cretaceous) conglomerate, sandstone, mudstone, and coal exposed on the south side of an unnamed drainage, approximately 3 kilometers (1.8 miles) east of Saddle Mountain in lower Cook Inlet (ﬁgs. 1 and 2). The initial signiﬁcance of this exposure was that it was the ﬁrst reported occurrence of nonmarine rocks of this age in outcrop in lower Cook Inlet, which helped constrain the Late Cretaceous paleogeography of the area and provided important information on the composition of latest Mesozoic sandstones in the basin. The Saddle Mountain section is thought to be an outcrop analog for Upper Cretaceous nonmarine strata penetrated in the OCS Y-0097 #1 (Raven) well, located approximately 40 kilometers (25 miles) to the south–southeast in Federal waters (ﬁg. 1). Atlantic Richﬁeld Company (ARCO) drilled the Raven well in 1980 and encountered oil-stained rocks and moveable liquid hydrocarbons between the depths of 1,760 and 3,700 feet. Completion reports on ﬁle with the Bureau of Ocean Energy Management (BOEM; formerly Bureau of Ocean Energy Management, Regulation and Enforcement, and prior to 2010, U.S. Minerals Management Service) either show ﬂow rates of zero or do not mention ﬂow rates. A ﬂuid analysis report on ﬁle with BOEM suggests that a wireline tool sampled some oil beneath a 2,010-foot diesel cushion during the ﬂ ow test of the 3,145–3,175 foot interval, but the recorded ﬂ ow rate was still zero (Kirk Sherwood, written commun., January 9, 2012). Further delineation and evaluation of the apparent accumulation was never performed and the well was plugged and abandoned. As part of a 5-year comprehensive evaluation of the geology and petroleum systems of the Cook Inlet forearc basin, the Alaska Division of Geological & Geophysical Surveys obtained a research permit from the National Park Service to access the relatively poorly understood ‘Saddle Mountain exposure’ that is located in the Lake Clark National Park and Preserve. This work was done in cooperation with the Alaska Division of Oil & Gas and U.S. Geological Survey (USGS) research geologists. This report expands on Magoon and others’ (1980) description of the exposure, presents new data on sandstone composition and reservoir quality, presents new geochemical data on petroleum extracted from the outcropping sandstone, and describes oil-bearing correlative strata penetrated by the Raven well. Although the exposure is more than a kilometer (0.6 mile) east of Saddle Mountain (ﬁg. 2), in this report we variously refer to it as the Saddle Mountain succession, Saddle Mountain section, or the rocks at Saddle Mountain underlain by Upper Jurassic strata of the Naknek Formation.

Alaska↗

USGS2013

Groundwater quality and water-well characteristics in the Kickapoo Tribe of Oklahoma Jurisdictional Area, central Oklahoma, 1948--2011

In 2012, the U.S. Geological Survey, in cooperation with the Kickapoo Tribe of Oklahoma, compiled historical groundwater-quality data collected from 1948 to 2011 and water-well completion information in parts of Lincoln, Oklahoma, and Pottawatomie Counties in central Oklahoma to support the development of a comprehensive water-management plan for the Tribe’s jurisdictional area. In this study, water-quality data from 155 water wells, collected from 1948 to 2011, were retrieved from the U.S. Geological Survey National Water Information System database; these data include measurements of pH, specific conductance, and hardness and concentrations of the major ions, trace elements, and radionuclides that have Maximum Contaminant Levels or Secondary Maximum Contaminant Levels in public drinking-water supplies. Information about well characteristics includes ranges of well yield and well depth of private water wells in the study area and was compiled from the Oklahoma Water Resources Board Multi-Purpose Well Completion Report database. This report also shows depth to water from land surface by using shaded 30-foot contours that were created by using a geographic information system and spatial layers of a 2009 potentiometric surface (groundwater elevation) and land-surface elevation. Wells in the study area produce water from the North Canadian River alluvial and terrace aquifers, the underlying Garber Sandstone and Wellington Formation that compose the Garber–Wellington aquifer, and the Chase, Council Grove, and Admire Groups. Water quality varies substantially between the alluvial and terrace aquifers and bedrock aquifers in the study area. Water from the alluvial aquifer has relatively high concentrations of dissolved solids and generally is used for livestock only, whereas water from the terrace aquifer has low concentrations of dissolved solids and is used extensively by households in the study area. Water from the bedrock aquifer also is used extensively by households but may have high concentrations of trace elements, including uranium, in some areas where groundwater pH is above 8.0. Well yields vary and are dependent on aquifer characteristics and well-completion practices. Well yields in the unconsolidated alluvial and terrace aquifers generally are higher than yields from bedrock aquifers but are limited by the thickness and extent of these river deposits. Well yields in the alluvium and terrace aquifers commonly range from 50 to 150 gallons per minute and may exceed 300 gallons per minute, whereas well yields in the bedrock aquifers commonly range from 25 to 50 gallons per minute in the western one-third of study area (Oklahoma County) and generally less than 25 gallons per minute in the eastern two-thirds of the study area (Lincoln and Pottawatomie Counties).

Oklahoma↗

USGS1993

Allostratigraphy of the U.S. middle Atlantic continental margin; characteristics, distribution, and depositional history of principal unconformity-bounded upper Cretaceous and Cenozoic sedimentary units

Publication of Volumes 93 and 95 ('The New Jersey Transect') of the Deep Sea Drilling Project's Initial Reports completed a major phase of geological and geophysical research along the middle segment of the U. S. Atlantic continental margin. Relying heavily on data from these and related published records, we have integrated outcrop, borehole, and seismic-reflection data from this large area (500,000 km^2 ) to define the regional allostratigraphic framework for Upper Cretaceous and Cenozoic sedimentary rocks. The framework consists of 12 alloformations, which record the Late Cretaceous and Cenozoic depositional history of the contiguous Baltimore Canyon trough (including its onshore margin) and Hatteras basin (northern part). We propose stratotype sections for each alloformation and present a regional allostratigraphic reference section, which crosses these basins from the inner edge of the coastal plain to the inner edge of the abyssal plain. Selected supplementary reference sections on the coastal plain allow observation of the alloformations and their bounding unconformities in outcrop. Our analyses show that sediment supply and its initial dispersal on the middle segment of the U. S. Atlantic margin have been governed, in large part, by hinterland tectonism and subsequently have been modified by paleoclimate, sea-level changes, and oceanic current systems. Notable events in the Late Cretaceous to Holocene sedimentary evolution of this margin include (1) development of continental-rise depocenters in the northern part of the Hatteras basin during the Late Cretaceous; (2) the appear ance of a dual shelf-edge system, a marked decline in siliciclastic sediment accumulation rates, and widespread acceleration of carbonate production during high sea levels of the Paleogene; (3) rapid deposition and progradation of thick terrigenous delta complexes and development of abyssal depocenters during the middle Miocene to Quaternary interval; and (4) deep incision of the shelf edge by submarine canyons, especially during the Pleistocene. Massive downslope gravity flows have dominated both the depositional and erosional history of the middle segment of the U. S. Atlantic Continental Slope and Rise during most of the last 84 million years. The importance of periodic widespread erosion is recorded by well-documented unconformities, many of which can be traced from coastal-plain outcrops to coreholes on the continental slope and lower continental rise. These unconformities form the boundaries of the 12 allostratigraphic units we formally propose herein. Seven of the unconformities correlate with supercycle boundaries (sequence boundaries) that characterize the Exxon sequence-stratigraphy model.

Professional Paper↗

USGS2021

Status and understanding of groundwater quality in the northern Sierra Nevada foothills domestic-supply aquifer study units, 2015–17—California GAMA Priority Basin Project

Groundwater quality in the northern Sierra Nevada foothills region of California was investigated as part of California State Water Resources Control Board (SWRCB) Groundwater Ambient Monitoring Assessment Priority Basin Project (GAMA-PBP). The region was divided into two study units: the Yuba-Bear watersheds (YBW) study unit and the American-Cosumnes-Mokelumne watersheds (ACMW) study unit. The GAMA-PBP made a spatially unbiased assessment of aquifer systems used for domestic drinking-water supply in the study region, which are predominantly composed of fractured, hard-rock aquifers of varying lithology. These assessments characterized the quality of raw groundwater to evaluate ambient conditions in the domestic-supply aquifer and not the quality of treated drinking water. The study included three components: (1) a status assessment , which characterized the quality of groundwater resources used for domestic drinking-water supply in the YBW and ACMW study units; (2) an understanding assessment , which evaluated natural and anthropogenic explanatory factors that could potentially affect groundwater quality in the study region; and (3) a comparative assessment between the groundwater resources used for domestic and public drinking-water supply in the study region. The status assessment was based on data collected by the GAMA-PBP from 74 sites in the YBW study unit during 2015–16 and 67 sites in the ACMW study unit from 2016 to 2017. To contextualize water-quality results, concentrations of water-quality constituents in ambient groundwater were compared to regulatory and non-regulatory benchmarks typically used by the State of California and Federal agencies as health-based or aesthetic standards for public drinking water. The status assessment used a grid-based method to estimate proportions of groundwater resources with concentrations approaching or exceeding benchmark thresholds. This method provides spatially unbiased results and allows inter-comparability with similar groundwater-quality assessments. Inorganic constituents with health-based benchmarks were present at high relative concentration (RC), meaning they exceeded the benchmark threshold, in 5.4 and 10 percent of domestic-supply aquifer systems in the YBW and ACMW study units, respectively. Inorganic constituents with aesthetic-based benchmarks were detected at high-RCs in 20 and 28 percent of the YBW and ACMW study units, respectively. The inorganic constituents present at high RC were arsenic, barium, boron, molybdenum, strontium, nitrate, adjusted gross-alpha particle activity, chloride, total dissolved solids, specific conductance, iron, manganese, and hardness. Groundwater samples were tested for presence or absence of three microbial indicators (total coliform, Escherichia coli , and Enterococci ). At least one microbial indicator was present in 26 and 28 percent of the YBW and ACMW study units, respectively. At least one organic constituent was detected in 30 and 42 percent of the YBW and ACMW study units, respectively. Organic constituents were not present at high RC, but tetrachloroethene (PCE), trichloroethene (TCE), and toluene were detected in the YBW study unit at moderate RC (between the benchmark concentration and one-tenth of the benchmark concentration). Methyl tert -butyl ether (MTBE) and chloroform were present at low RC (less than one-tenth of the benchmark concentration) in the YBW and ACMW study units with detection frequencies greater than 10 percent. Perchlorate, a constituent of special interest, was detected in 31 and 41 percent of the YBW and ACMW study units, respectively, at either low or moderate RCs. Relations among select water-quality constituents and potential explanatory factors were evaluated using statistical and graphical approaches. Nitrate, microbial indicators, and perchlorate were all correlated to elevation-dependent variables relating to climate, land use, and recharge condition. Isotopic and dissolved noble-gas tracers indicated these water-quality constituents are associated with recharge conditions associated with irrigation during the summer dry-season, which is common in areas of rural-residential or agricultural land uses. Higher concentrations of iron and manganese were primarily associated with anoxic groundwater in aquifers of metasedimentary lithology. Increased hardness was primarily associated with anoxic groundwater in aquifers of mafic-ultramafic or metavolcanics lithologies at lower elevations in the study region in the Melones fault zone. Chloroform and MTBE were associated with shallow groundwater (wells depths less than 130 m) under oxic and anoxic redox conditions, respectively. The comparative assessment evaluated differences between the aquifer systems used for domestic- and public-supply in study region based on (1) well-construction characteristics, and (2) water quality. Analysis of over 60,000 well-completion reports in the study region showed that although domestic-supply wells span the deepest depth zones in regional aquifers, median depths for public-supply wells were significantly greater than those of domestic-supply wells in both study units. Water-quality data from more than 300 public-supply wells in the study region were assessed using a spatially weighted method for calculation aquifer-scale proportions and compared with the domestic-supply assessment results. Detections of inorganic constituents at high RC and detection frequencies for organic constituents were generally similar between the domestic- and public-supply aquifer systems in both study units, with a few notable exceptions in the ACMW study unit: nitrate was greater for the public- compared to domestic-supply aquifer system and both manganese, hardness, and MTBE were greater in the domestic- compared to public-supply aquifer system. These differences are likely related to contrasting land uses, aquifer lithologies, landscape positions, and depths characterizing domestic- and public-supply wells in the ACMW study unit. Overall, fewer samples from domestic-supply wells in the northern Sierra Nevada foothills exceeded health-based benchmarks compared to aesthetic-based benchmarks for groundwater quality. Exceedences of health-based benchmarks were primarily caused by nitrate and coliform bacteria, which were associated with recharge from diverted surface water used primarily for irrigation. Exceedences of aesthetic-based benchmarks were primarily caused by iron, managanese, and hardness, which were associated with geologic factors. Regional irrigation practices and aquifer lithology can affect groundwater quality in fractured-rock aquifers in the northern Sierra Nevada foothills used for domestic drinking-water supply.

California↗

USGS1899

Water resources of the Lower Peninsula of Michigan

This material is a portion of the outcome of Dr. Lane's studies in connection with the geological survey of the State of Michigan, supplemented by statements received in reply to circulars sent throughout the Lower Peninsula of Michigan to well drillers and others likely to be well informed and interested in the subject. The facts thus gathered have been collated with the result of two months' field work during the autumn of 1897. The complete report has assumed such bulk that it has been found necessary to divide it into several parts. The first of these, containing the general conclusions, is herewith presented. The remaining data fall naturally into two classes, the first consisting of analyses of waters and the second of detailed descriptions of the supply at various localities visited.

Michigan↗

USGS2015

Snake River fall Chinook salmon life history investigations, 1/1/2013 – 12/31/2013

Smallmouth bass predation on subyearling fall Chinook salmon was examined in the upper portion of Lower Granite Reservoir during 2013. During the time subyearlings were present in the reservoir, smallmouth bass were collected, their stomach contents removed for diet analysis, and their abundance estimated with mark-recapture techniques. In 2013, the greatest consumption of subyearlings by smallmouth bass occurred in late May and early June—as much as 50% of their diet by weight. Sand rollers were the most common non-salmonid fish consumed by smallmouth bass. In the section of the reservoir above the confluence with the Clearwater River, the abundance of bass was higher in non-riprap habitat than in riprap, but the opposite was true in the section below the confluence. We estimated that over 168,000 subyearlings were lost to smallmouth bass predation in 2013. Given the predominance of sand rollers in the diet of smallmouth bass, we believe this species reduces predation on subyearling fall Chinook salmon. A complete report of our findings is provided in the Appendix.

Washington↗