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This paper presents a comprehensive review and amplification of the writer's earlier slope development theory. In particular, the influence of lithology on evolving slope profiles is investigated and calculations are made for various conditions, such as presence of caprock, soft bottom, and hard and soft intermediate layers.
To find out, scientists from the U. S. Geological Survey (USGS) tested walleye and other sport fish from the upper Columbia River and Franklin D. Roosevelt Lake (Lake Roosevelt), the largest reservoir in Washington and a popular fishing spot. Findings: Walleye had higher concentrations of mercury than other sport fish. Larger walleye had higher mercury concentrations than smaller walleye. Mercury concentrations in walleye fillets ranged from 0.11 to 0.44 parts per million (ppm). These concentrations do not exceed the current Federal standard (1.0 ppm of mercury) designed to protect the health of people who eat small amounts of fish. After reviewing these findings, the Washington State Department of Health concluded that people who regularly consume large amounts of Lake Roosevelt walleye may be at risk of adverse health effects from mercury and should limit their consumption of these fish.
Executive Summary We summarized inventory and monitoring efforts for plants and vertebrates at Organ Pipe Cactus National Monument (NM) in Arizona. We used data from previous research to compile complete species lists for the monument and to assess inventory completeness. There have been 1,031 species of plants and vertebrates observed at the monument. Most of the species on the list are documented by voucher specimens. There are 59 non-native species established in the monument: one mammal, three birds, and 55 non-native plants. Most non-native plant species were first recorded along roads. In each taxon-specific chapter, we highlight areas that contribute disproportionately to species richness or that have unique species for the monument. Of particular importance are Quitobaquito Springs and Pond, which are responsible for the monument having one of the highest number of bird species in the Sonoran Desert Network of parks. Quitobaquito also contains the only fish in the monument, the endangered Quitobaquito pupfish (Cyprinodon eremus). Other important resources for the plants and vertebrates include the xeroriparian washes (e.g., Alamo Canyon) and the Ajo Mountains. Based on the review of past studies, we believe the inventories of vascular plants and vertebrates are nearly complete and that the monument has one of the most complete inventories of any unit in the Sonoran Desert Network.
Executive Summary We summarize past inventory efforts for vascular plants and vertebrates at Montezuma Castle National Monument (NM) in Arizona. We used data from previous research to compile complete species lists for the monument and to assess inventory completeness. There have been 784 species recorded at Montezuma Castle NM, of which 85 (11%) are non-native. In each taxon-specific chapter we highlight areas of resources that contributed to species richness or unique species for the monument. Of particular importance are Montezuma Well and Beaver and Wet Beaver creeks and the surrounding riparian vegetation, which are responsible for the monument having one of the highest numbers of bird species in the Sonoran Desert Network of park units. Beaver Creek is also home to populations of federally-listed fish species of concern. Other important resources include the cliffs along the creeks and around Montezuma Well (for cliff and cave roosting bats). Based on the review of past studies, we believe the inventory for most taxa is nearly complete, though some rare or elusive species will be added with additional survey effort. We recommend additional inventory, monitoring and research studies.
Alteration of natural river flows resulting from the construction and operation of dams can result in substantial changes to downstream aquatic and bottomland ecosystems and undermine the long-term health of native species and communities (for general review, cf. Ward and Stanford, 1995; Baron and others, 2002; Nilsson and Svedmark, 2002). Increasingly, land and water managers are seeking ways to manage reservoir releases to produce flow regimes that simultaneously meet human needs and maintain the health and sustainability of downstream biotaa.
Magnetic concentrates recovered readily by hand magnet from alluvial sediments or panned concentrates have been used successfully in exploration as a geochemical sample medium for Cu, Zn, Co, Cr, Mo, Ni, V, Sn, and Be, particularly in arid environments where alluvial sediments may be contaminated by aeolian debris. Opportunity for this use arose recently as chemical and spectrographic techniques were developed to determine the abundances of a variety of trace elements in Fe-rich media. The use of analytical data from magnetic concentrates was introduced as one of several anomaly-enhancement techniques based on heavy minerals and intended to identify blind ore deposits. An extensive literature, reviewed here, on the relation of the chemical composition of the mineral magnetite, a main component of magnetic concentrates, to geologic conditions of origin, facilitates the interpretation of trace-element data in the context of association with ore deposits.
The common goal of flood-plain regulation and use is protecting life, minimizing public expenditures, and reducing flood loss. A comprehensive program combining structural and nonstructural measures can yield substantial benefits and may present a practical approach for managing a flood plain. A review of flood-plain planning, management, and regulation in the San Francisco Bay region, Calif., as shown by a study of Napa County , demonstrates complex multijurisdictional involvements. (Woodard-USGS)
More than 1,200 titles and abstracts of limnological studies of ponds, reservoirs, and lakes (excluding Lakes Erie and Ontario) are compiled in one volume. Publications cited date from the late 19th century through 1974. Titles and abstracts are presented alphabetically by author's name; cross indexes of coauthors, locations, and subjects are also provided. Authors' abstracts were used if available; the remainder were written by the compilers of this volume and are so designated. Some of the publications cited could not be obtained for review; they are given complete reference but have no accom panying abstract. This compilation is an exhaustive index to limnological studies within the State. It is intended for use mainly by those concerned with water-use planning, water management, and lake ecology.
No abstract available at this time
Hydrologic data for the Dead Sea area were reviewed to assess the probable magnitude and rate of change of the water level of the Dead Sea. Historical average annual Dead Sea levels range from a minimum of 399.4 meters below sea level in about 1818 to a maximum of 388.6 meters below in 1896. Present levels are rapidly approaching the historical low. There is a close correlation between Dead Sea level and accumulated departure from the mean of long-term rainfall except for the most recent period since 1964. During that period rainfall has been near the long-term average but water levels have continued to decline, in part due to abstractions for irrigation in the Jordan River basin. The dissolved-solids concentration of Dead Sea water presently is approximately 322,000 milligrams per liter and is generally well mixed throughout. This concentration is at the saturation level, resulting in continuous precipitation of some salts. The increase in dissolved solids to the present high concentration has resulted in an evaporation rate less than that estimated in previous reports. Evaporation rate from the North Basin is estimated at 1,310 millimeters per year at present. The evaporation rate from the South Basin was not estimated due to extensive existing or planned modifications for mineral production facilities. Water budget computations were performed at various inflow rates in order to project water-level changes for 50 years. Computations assumed closure of the South Basin by existing and proposed mineral extraction facilities. The projected 50-year changes ranged from a decline of 51 meters with no inflow from any sources to a rise of 10.2 meters when average annual inflow from the Jordan River was 750 cubic hectometers. An average annual inflow to the Sea of 900 cubic hectometers from all sources is required to stabilize the Sea at the present level. Principal impact of declining water levels on proposed potash production facilities in Jordan would be an increase in power requirements. A cursory review of a proposed plan to divert water from the Mediterranean Sea into the Dead Sea to generate electric power and stabilize water levels indicates a very limited impact on chemical, physical, and ecological characteristics of the Dead Sea in the near future. Water-budget computations indicate that if all but 200 cubic hectometers of tributaries' waters were utilized for irrigation and other purposes, a maximum diversion of 700 cubic hectometers per year into the Dead Sea would be possible without significantly raising long-term average water levels.
Lake eutrophication is a large and growing problem in many parts of the world, commonly due to anthropogenic sources of nutrients. Improved quantification of nutrient inputs is required to address this problem, including better determination of exchanges between groundwater and lakes. This first of a two-part review provides a brief history of the evolution of the study of groundwater exchange with lakes, followed by a listing of the most commonly used methods for quantifying this exchange. Rates of exchange between lakes and groundwater compiled from the literature are statistically summarized for both exfiltration (flow from groundwater to a lake) and infiltration (flow from a lake to groundwater), including per cent contribution of groundwater to lake-water budgets. Reported rates of exchange between groundwater and lakes span more than five orders of magnitude. Median exfiltration is 0.74 cm/day, and median infiltration is 0.60 cm/day. Exfiltration ranges from near 0% to 94% of input terms in lake-water budgets, and infiltration ranges from near 0% to 91% of loss terms. Median values for exfiltration and infiltration as percentages of input and loss terms of lake-water budgets are 25% and 35%, respectively. Quantification of the groundwater term is somewhat method dependent, indicating that calculating the groundwater component with multiple methods can provide a better understanding of the accuracy of estimates. The importance of exfiltration to a lake budget ranges widely for lakes less than about 100 ha in area but generally decreases with increasing lake area, particularly for lakes that exceed 100 ha in area. No such relation is evident for lakes where infiltration occurs, perhaps because of the smaller sample size. Copyright © 2014 John Wiley & Sons, Ltd.
This book is intended to replace the instructions relating to the topographic work of the United States Geological Survey, issued as a part of the general Survey, instructions of 1903, which are now in many respects obsolete, although revised portions of them have, from time to time, been issued as circular letters or printed leaflets. The several portions of this book were prepared by the members of the topographic branch best qualified for the task and were assembled and revised by the division chiefs and finally reviewed by the chief geographer. It is desired to make the instructions complete so far as the technical work of map making is concerned and to reduce to a minimum the necessity for personal instructions.
The U.S. Geological Survey is active in the development and use of models for the analysis of various types of surface-water problems. Types of problems for which models have been, or are being developed, include categories such as the following: (1)specialized hydraulics, (2)flow routing in streams, estuaries, lakes, and reservoirs, (3) sedimentation, (4) transport of physical, chemical, and biological constituents, (5) surface exchange of heat and mass, (6) coupled stream-aquifer flow systems, (7) physical hydrology for rainfall-runoff relations, stream-system simulations, channel geometry, and water quality, (8) statistical hydrology for synthetic streamflows, floods, droughts, storage, and water quality, (9) management and operation problems, and (10) miscellaneous hydrologic problems. Following a brief review of activities prior to 1970, the current status of surface-water modeling is given as being in a developmental, verification, operational, or continued improvement phase. A list of recently published selected references, provides useful details on the characteristics of models.
Introduction The U.S. Geological Survey’s (USGS) concept of a national census (or accounting) of water resources has evolved over the last several decades as the Nation has experienced increasing concern over water availability for multiple competing uses. The implementation of a USGS National Water Census was described in the USGS 2007 science strategy document that identified the highest priority science topics for the decade 2007–17. In 2009, the SECURE Water Act (Public Law 111–11, subtitle F) authorized the USGS to create a Water Availability and Use Assess­ment Program for the Nation, and in 2012, the Department of the Interior WaterSMART initiative provided funding to begin implementation of the USGS National Water Census (NWC). Generally, the USGS NWC approaches water-availability assessment in terms of a “water budget.” The water-budget approach seeks to better quantify the inflows and outflows of water, as well as the change in storage volume, both nationally and at a regional scale and, by doing so, provides critical information to managers and stakeholders responsible for making water-availability decisions. The NWC has two primary components: Topical Studies and Geographic Focus Area Studies. Topical Studies do research on methods that can provide nationwide estimates of particular water-budget components at the subwatershed scale. Some examples of NWC Topical Studies include estimation of streamflow at ungaged locations; periodic quantification of evapotranspiration; and water use related to development of unconventional oil and gas. These efforts are planned to include additional topics in the future. Geographic Focus Area Studies (FASs) assess water availability and use within a defined geographic area, typically a surface-water drainage basin, to increase the understanding of factors affecting water availability in the region. In the FASs, local stakeholder input helps the USGS identify what components of the water budget are in most need of additional understanding or quantification. Focus Area Studies are planned as 3-year efforts and, typically, three FASs are ongoing in different parts of the country at any given time. The Colorado River Basin (CRB) and the Delaware and Apalachicola-Chattahoochee-Flint (ACF) River Basins were selected by the Department of the Interior for the first round of FASs because of the perceived water shortages in the basins and potential conflicts over water supply and allocations. After gathering input from numerous stakeholders in the CRB, the USGS determined that surface­-water resources in the basin were already being closely monitored and that the most important scientific contribution could be made by helping to improve estimates of four water­-budget components: evapotranspiration losses, snowpack hydrodynamics, water­-use information, and the relative importance of groundwater discharge in supporting streamflow across the basin. The purpose of this fact sheet is to provide a brief summary of the CRB FAS results as the study nears completion. Although some project results are still in the later stages of review and publication, this fact sheet provides an overall description of the work completed and cites the publications in which additional information can be found.
Initiated in 1995, the Antarctic Digital Magnetic Anomaly Project (ADMAP) produced the first magnetic anomaly map of the Antarctic region south of 60 o S (Golynsky et al., 2001). This map synthesized over 7.1 million line-kms of survey data available up through 1999 from marine, airborne and Magsat satellite observations. Since the production of the initial map, a large number of new marine and airborne surveys and improved magnetic observations from the Ørsted and CHAMP satellite missions have become available. In addition, an improved core field model for the Antarctic has been developed to better isolate crustal anomalies in these data. The next generation compilation also will likely represent the magnetic survey observations of the region in terms of a high-resolution spherical cap harmonic model. In this paper, we review the progress and problems of developing an improved magnetic anomaly map to facilitate studies of the Antarctic crustal magnetic field
The Aggregate Water-Use Data System (AWUDS) is the database management system used to enter, store, and analyze state aggregate water-use data. It is part of the U.S. Geological Survey National Water Information System. AWUDS has a graphical user interface that facilitates data entry, revision, review, and approval. This document provides information on the basic functions of AWUDS and the steps for carrying out common tasks that are a part of compiling an aggregated dataset. Also included are explanations of terminology and descriptions of user-interface structure, procedures for using the AWUDS operations, and dataset-naming conventions. Information on water-use category definitions, data-collection methods, and data sources are found in the report “Guidelines for preparation of State water-use estimates,” available at https://pubs.er.usgs.gov/publication/ofr20171029 .
The disease caused by the amphibian chytrid fungus Batrachochytrium salamandrivorans (Bsal) has caused mass mortality of salamanders across Europe (Stegen et al. 2017; amphibians are not known to be susceptible to the disease (Martel et al. 2014). Bsal puts North American amphibian biodiversity at risk (Martel et al. 2014; Gray et al. 2015) despite imports of potentially infected amphibians (USFWS 2016; WAPTR 2018; Grear et al. 2021). Recently, the U.S. has announced the finalization of the 2016 interim rule to the Lacey Act (USFWS 2016) to restrict imports of all species of salamanders from 20 genera to the list of injurious amphibians and has added 16 genera to the injurious amphibian list in a new interim rule in response to updated research on salamander susceptibility to Bsal infection (USFWS 2025). A large-scale survey across the USA failed to detect Bsal in over 10,000 individuals (Waddle et al. 2020), and ongoing efforts by North American colleges and universities are similarly conducting Bsal surveillance without more recent detection (e.g., Hyman and Hill 2024). Concerned amphibian and disease specialists nevertheless are preparing for a Bsal invasion into North America (Grant et al. 2017; Olson et al.2024). Despite the initial survey results, the risk of Bsal incursion into North America remains due to broad host susceptibility of North American amphibian species (Gray et al. 2023). The major driver of Bsal introduction risk in the U.S. is expected to be captive amphibian release (Cunningham et al. 2015; Grear et al. 2021). Bsal primarily affects salamanders but anuran species can also be vectors (e.g., Towe et al. 2021; Monzon et al. 2022; Gray et al. 2023; Olson et al. 2024), increasing the risk of a released amphibian carrying Bsal into the natural environment (Grear et al. 2021). An early survey of pet salamanders in the United States did not detect Bsal (Klocke et al. 2017), but even one animal released with Bsal could have a major effect on local amphibians. Early detection and rapid response can improve host outcomes (Bletz et al. 2024; Gray et al. 2018), but the lack of timely knowledge about unwanted release of non-native pets to natural systems causes inevitable delay. Herein, we describe our experience responding to a report of a released non-native amphibian species, common in the pet trade (Gerson 2012; Maximo et al. 2021). We suggest improvements to early detection and rapid response efforts for amphibians and amphibian disease
This report discusses a method for interpreting a layered slowness or velocity model from surface-source downhole seismic data originally presented by Boore (2003). I have implemented this method in the statistical computing language R (R Development Core Team, 2007), so that it is freely and easily available to researchers and practitioners that may find it useful. I originally applied an early version of these routines to seismic cone penetration test data (SCPT) to analyze the horizontal variability of shear-wave velocity within the sediments in the San Francisco Bay area (Thompson et al., 2006). A more recent version of these codes was used to analyze the influence of interface-selection and model assumptions on velocity/slowness estimates and the resulting differences in site amplification (Boore and Thompson, 2007). The R environment has many benefits for scientific and statistical computation; I have chosen R to disseminate these routines because it is versatile enough to program specialized routines, is highly interactive which aids in the analysis of data, and is freely and conveniently available to install on a wide variety of computer platforms. These scripts are useful for the interpretation of layered velocity models from surface-source downhole seismic data such as deep boreholes and SCPT data. The inputs are the travel-time data and the offset of the source at the surface. The travel-time arrivals for the P- and S-waves must already be picked from the original data. An option in the inversion is to include estimates of the standard deviation of the travel-time picks for a weighted inversion of the velocity profile. The standard deviation of each travel-time pick is defined relative to the standard deviation of the best pick in a profile and is based on the accuracy with which the travel-time measurement could be determined from the seismogram. The analysis of the travel-time data consists of two parts: the identification of layer-interfaces, and the inversion for the velocity of each layer. The analyst usually picks layer-interfaces by visual inspection of the travel-time data. I have also developed an algorithm that automatically finds boundaries which can save a significant amount of the time when analyzing a large number of sites. The results of the automatic routines should be reviewed to check that they are reasonable. The interactivity of these scripts allows the user to add and to remove layers quickly, thus allowing rapid feedback on how the residuals are affected by each additional parameter in the inversion. In addition, the script allows many models to be compared at the same time.