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At least 1,153 records · Page 64Linked to original sources

USGS2013

A conceptual framework for Lake Michigan coastal/nearshore ecosystems, with application to Lake Michigan Lakewide Management Plan (LaMP) objectives

The Lakewide Management Plans (LaMPs) within the Great Lakes region are examples of broad-scale, collaborative resource-management efforts that require a sound ecosystems approach. Yet, the LaMP process is lacking a holistic framework that allows these individual actions to be planned and understood within the broader context of the Great Lakes ecosystem. In this paper we (1) introduce a conceptual framework that unifies ideas and language among Great Lakes managers and scientists, whose focus areas range from tributary watersheds to open-lake waters, and (2) illustrate how the framework can be used to outline the geomorphic, hydrologic biological, and societal processes that underlie several goals of the Lake Michigan LaMP, thus providing a holistic and fairly comprehensive roadmap for tackling these challenges. For each selected goal, we developed a matrix that identifies the key ecosystem processes within the cell for each lake zone and each discipline; we then provide one example where a process is poorly understood and a second where a process is understood, but its impact or importance is unclear. Implicit in these objectives was our intention to highlight the importance of the Great Lakes coastal/nearshore zone. Although the coastal/nearshore zone is the important linkage zone between the watershed and open-lake zones—and is the zone where most LaMP issues are focused--scientists and managers have a relatively poor understanding of how the coastal/nearshore zone functions. We envision follow-up steps including (1) collaborative development of a more detailed and more complete conceptual model of how (and where) identified processes are thought to function, and (2) a subsequent gap analysis of science and monitoring priorities.

Lake Michigan↗

USGS2020

Louisiana Coastal Zone sediment characterization; comparison of sediment grain sizes for samples collected in 2008 and 2015–2016 from the western Chenier plain to the Chandeleur Islands, Louisiana—Louisiana Barrier Island Comprehensive Monitoring (BICM) Program

Repeated sampling and grain-size analysis of surficial sediments along the sandy shorelines of Louisiana is necessary to characterize coastal-zone sediment properties and evaluate sediment transport patterns within the nearshore environments. In 2008, and again in 2015 and 2016, sediment grab samples were collected along the shorelines of the western Chenier plain, the Isles Dernieres (Raccoon, Whiskey, Trinity and East Islands), the Lafourche delta (Timbalier Islands, Caminada Headland, and Grand Isle), the modern delta (Grand Terre Islands from Chaland Headland to Sandy Point), and the Chandeleur Islands (from Curlew Island to Hewes Point). The samples were collected as part of the Louisiana Coastal Protection and Restoration Authority (CPRA) Barrier Island Comprehensive Monitoring (BICM) Program in collaboration with the U.S. Geological Survey St. Petersburg Coastal and Marine Science Center (USGS–SPCMSC) and the University of New Orleans Pontchartrain Institute for Environmental Studies (UNO–PIES). Physical properties of the samples (sediment grain size and sorting) were measured and provided in data reports to CPRA. Additional samples collected by the USGS from around Breton Island in 2014 and 2015 supplemented the 2015–2016 BICM data to complete the coastwide dataset. This report compares the results of the 2008 and 2015–2016 sedimentologic analyses and documents changes in composition (percent sand) and mean sediment grain size between the two time periods. At most sample sites, differences in mean grain size varied by less than ±0.25 Φ. The largest changes occurred at sites located near tidal inlets or along rapidly eroding shorelines.

Louisiana↗

USGS1983

Multichannel seismic measurements on the northern edge of the Bahaman-Cuban collision zone

This paper presents geophysical data obtained, in the western reaches of the Old Bahama Channel separating Cuba and the Bahamas (Figure 1). These data were collected as part of an ongoing investigation of Caribbean and Bahaman geology primarily conducted by University of Miami and the U.S. Geological Survey (USGS). The work was done on the R/V Gilliss of Rosenstiel School of Marine and Atmospheric Sciences, (RSMAS), University of Miami. The scientific party included members of the Woods Hole Oceanographic Institute (WHOI) and RSMAS.

Open-File Report↗

USGS2011

A previously unreported locality record for the Gila monster ( Heloderma suspectum )

Although the Gila Monster (Heloderma suspectum) is widely distributed throughout the Sonoran and portions of the Mojave Deserts of the southwestern United States and northwestern Mexico, details of its distribution in California are imperfectly known, due to the apparent rarity of the species in that state. In their review of Gila Monster records for California, Lovich and Beaman (2007) documented only 26 credible sightings during a period of 153 years. In May 2009 another sighting in California was documented by Ruppert (2010a, b) who photographed a specimen in the Providence Mountains, an area known for previous Gila Monster sightings (Lovich and Beaman 2007). In this paper we report the 28th credible record of a Gila Monster in California.

California↗

USGS2021

Informing future condition scenario planning for habitat specialists of the imperiled pine rockland ecosystem of South Florida

This project evaluated habitat conditions for two species found in the imperiled pine rockland ecosystem—the Rim Rock Crowned Snake ( Tantilla oolitica ) and the Key Ring-Necked Snake ( Diadophis punctatus acricus ). The Rim Rock Crowned Snake historically occurred in eastern Miami-Dade County (hereafter, mainland) as well as throughout the Florida Keys, whereas the Key Ring-Necked Snake occurs only in lower Florida Keys (Enge et al. 2004; Mays and Enge 2016). Both species are very elusive, small (< 20 cm in length) and primarily fossorial. Pine rockland habitat is rapidly disappearing in South Florida, with < 3 percent of its original extent remaining. Saltwater intrusion from hurricanes and sea-level rise (SLR), and human development pose the greatest threats to the longevity of this ecosystem which, in turn, places species that are endemic to this unique habitat at risk of extinction. The Rim Rock Crowned Snake and the Key Ringed-Necked Snake are being considered for listing by the U.S. Fish and Wildlife Service (USFWS). To aid the agency’s decision, it must be able to forecast species’ responses to potential future environmental conditions, as well as to different conservation and management actions. Yet, the information needed to complete these forecasts—such as population trends, life history traits, habitat use, and future land use and climate conditions—is often lacking for most rare species. This is especially problematic for assessments of species resiliency to changes in climate and land use. When these types of data are lacking, information on habitat quality can be used to help determine how a species will respond to change. First, this project gathered current and historical records for both species from various sources such as museum specimens, inventories, and other personal account. Then, we identified potential future changes in habitat that could result from different management actions, such as habitat acquisition or restoration, and environmental conditions, such as changes in the frequency and intensity of tropical storms and rates of SLR. Researchers then explored the potential impacts of these habitat condition changes on the Rim Rock Crowned Snake and Key Ring-Necked Snake. This information can be used by the USFWS to help make decisions about the need to protect these species under the Endangered Species Act and could inform the conservation, management, and recovery of other at-risk species found in the pine rockland ecosystem. This work supports the Secretary of Interior’s priority to create a conservation stewardship legacy by using science to identify best practices to manage land and water resource and adapt to changes in the environment.

Florida↗

USGS2026

Science for drought response

Droughts impact water availability and quality, agriculture, energy production, ecosystem health, cultural resources, and wildfire risk. In an average year, nearly 15% of the US experiences significant drought, and in some recent years, drought conditions have impacted more than a third of the nation (U.S. Drought Monitor). The U.S. Geological Survey (USGS) Climate Adaptation Science Centers (CASCs) deliver actionable science to help land and resource managers prepare for, reduce the risk of, and recover from drought.

Report↗

USGS1990

Map showing distribution of gold in stream-sediment samples, Richfield 1° x 2° quadrangle, Utah

This map of the Richfield 1° x 2° quadrangle, Utah, shows the regional distribution of gold in the less-than-0.180-mm (minus-80-mesh) fraction of stream sediments. It is part of a folio of maps of the Richfield 1° x 2° quadrangle, Utah, prepared under the Conterminuous United States Mineral Assessment Program. Other published geochemical maps in this folio are listed in the Selected References of this report. The Richfield quadrangle is located in west-central Utah and includes the eastern part of the Pioche-Marysvale igneous and mineral belt, which extends from the vicinity of Pioche in southeastern Nevada, east-northeastward for 155 miles into central Utah. The western two-thirds of the Richfield quadrangle is part of the Basin and Range province, whereas the eastern third is part of the High Plateaus of Utah, a subprovince of the Colorado Plateau. Bedrock in the northern part of the Richfield quadrangle consists predominantly of Late Proterozoic and Paleozoic sedimentary strata that were thrust eastward during the Sevier orogeny in Cretaceous time onto an autochthon of Mesozoic sedimentary rocks located in the eastern part of the quadrangle. The southern part of the quadrangle is largely underlain by Oligocene and younger volcanic rocks and related intrusions. Extensional tectonism in late Cenozoic time broke the bedrock terrain into a series of north-trending fault blocks; the uplifted mountain areas were eroded to various degrees and the resulting debris was deposited in adjacent basins. Most of the mineral deposits in the Pioche-Marysvale mineral belt were formed as a result of igneous activity in the middle and late Cenozoic time. A more complete description of the geology and a mineral-resource appraisal of the Richfield quadrangle appears in Steven and Morris (1984 and 1987). The regional sampling program was designed to define broad geochemical patterns and trends that can be utilized along with geological and geophysical data to assess the mineral-resource potential for this quadrangle. Reconnaissance geochemical surveys are valuable tools in mineral exploration, especially when used in conjunction with data obtained from other earth science disciplines. Identifying specific exploration targets generally involves additional, more detailed investigations.

Utah↗

USGS2013

Fishery population and habitat assessment in Puerto Rico streams: Phase 2 final report

This document serves as the Final Report for research on Puerto Rico stream fishes and their habitat funded by the Puerto Rico Department of Natural and Environmental Resources, in the form of a grant to the North Carolina Cooperative Fish and Wildlife Research Unit. This research was also conducted to meet the thesis requirement for a Master of Science degree granted to Elissa Buttermore (Chapters 3–4) and the dissertation requirement for a Doctor of Philospophy degree granted to William Smith (Chapters 5–8). Formatting differs among chapters, as each was developed to target a specific scientific journal and to conform to journal style.

Puerto Rico↗

USGS2019

Spatial integration of biological and social objectives to identify priority landscapes for waterfowl habitat conservation

Waterfowl population management and habitat conservation compose one of the oldest and most successful adaptive management frameworks in the world. Since its inception, the North American Waterfowl Management Plan (NAWMP) has emphasized strategically targeted conservation investments in regions that most affect waterfowl population dynamics. By 2012, regional conservation had progressively become more science-based and strategic: many migratory bird partnerships had initiated or completed projects on mapping and modeling waterfowl distribution and abundances using geospatial techniques. However, when developing a map depicting and titled “Areas of Greatest Continental Significance to North American Ducks, Geese, and Swans” for the 2012 NAWMP Revision, waterfowl professionals articulated the need for improved decision frameworks and use of consistent datasets for refining large-scale spatial products depicting priority areas for waterfowl and people. This report describes a framework for developing a spatial value model to support the identification of North American geographies of importance to waterfowl during the breeding and non-breeding periods and to resource users who could potentially support (financially and (or) politically) waterfowl habitat conservation. Objectives used to identify priority geographies were determined through a collaborative process of the NAWMP Science Support Team, Priority Landscapes Committee (PLC), and other experts in the fields of waterfowl biology and ecology, environmental science, and human dimensions. ArcGIS Desktop was used as the platform for managing, analyzing, combining and displaying the spatial data as well as producing new data through spatial analysis functions. Thirty-eight spatial layers were developed, and several composite spatially explicit products (maps of North America) were produced based on PLC recommendations. The composite products have extensive similarities to the 2012 NAWMP map depicting areas of greatest continental significance to North American waterfowl. There are also some differences, especially in regions of the high Arctic and in Mexico. These differences between spatial value model maps and the 2012 NAWMP output likely arose from inclusion of social objectives, reduced dependence on expert opinion to generate abundance estimates, lack of population surveys in some regions and availability of expanded survey data in other regions, and use of model-based waterfowl population estimates for some unsurveyed areas. The structured decision-making framework application in this study is discussed, and the appropriate use of the products and their limitations are outlined. Additionally, options for future improvements are presented by identifying gaps in data collection, waterfowl-habitat association assumptions, and uncertainties related to social objectives. These spatial products are intended for use by national, regional, and province/state level wildlife professionals to aid their decisions in targeting waterfowl habitat conservation.

Open-File Report↗

USGS2012

User’s guide and metada for the PICES Nonindigenous Species Information System

Introduction Welcome to the PICES Nonindigenous Species Information System, a Microsoft Access database that displays the biogeographic distributions, invasion status, vectors, and key life history attributes of the approximately 740 reported nonindigenous species (NIS) in the estuarine and near-coastal habitats of the North Pacific and Hawaii. This database was developed by the U.S. Environmental Protection Agency and the U.S. Geological Survey under the auspices of Working Group 21 (Invasive Species) of the North Pacific Marine Science Organization (PCIES). The PICES database contains the data used to generate the “Atlas of Nonindigenous Marine and Estuarine Species in the North Pacific” (Lee and Reusser, 2012; herein referred to as the “Atlas”). The User’s Guide provides instructions on how to use the PICES database as well as metadata for the database and the Atlas. We note that for most users, the Atlas provides a simpler approach to accessing key information on NIS in the PICES countries than the database, though the database does provide additional information on species and sources as well as allowing users to extract information on specific taxa and/or locations (see Section 4). The PICES database also includes species reported from the PICES Rapid Assessment Surveys (RAS). PICES sponsored four rapid assessment surveys with the objective of quickly characterizing the native, non-native, and cryptogenic species present in different locations. Surveys were sponsored in Dalian, China in 2008, Jeju, Korea in 2009, Newport, Oregon, USA in 2010, and Peter the Great Bay, near Vladivostok and Nakhodka, Russia in 2011 ( http://www.pices.int/publications/pices_press/volume19/v19_n1/pp_30-31_Kobe-WS_f.pdf , http://www.pices.int/publications/pices_press/volume20/v20_n1/pp_26-29_RAS-2011.pdf ). The PICES database contains the RAS species that were made available in time for inclusion. Thus, the database does not capture all the species found in these surveys. In addition, much of the information on the RAS species was provided by the experts conducting the survey, and their distributions, environmental requirements, and life history attributes were not evaluated to the same level of detail by the PICES authors as the North Pacific NIS. In lieu of the more extensive review as conduced with the Atlas species, the information on the RAS species needs to be considered preliminary. Additionally, it is important to use the “Map All Distributions” option (see Section 3.6.6) when mapping their distribution or conducting a query. The general reference for the RAS surveys in the PICES database is “PICES Working Group 21, YEAR SURVEY”. The overall goal of both the database and Atlas was to simplify and standardize the dissemination of distributional, habitat, and life history characteristics of near-coastal and estuarine nonindigenous species. This database provides a means of querying these data and displaying the information in a consistent format. The specific classes of information the database captures include: Regional and global ranges of native and nonindigenous near-coastal and estuarine species at different hierarchical spatial scales. Habitat and physiological requirements of near-coastal and estuarine species. Life history characteristics of near-coastal and estuarine species. Invasion history and vectors for nonindigenous species. This standardized and synthesized data in the database and the Atlas provide the basic information needed to address a number of managerial and scientific needs. Thus, users will be able to: Create a baseline on the extent of invasion by region in order to assess new invasions. Use existing geographical patterns of invasion to gain some insights into potential new invaders. Use existing geographical patters of invasion to gain some insights into mechanisms affecting relative invasibility of different areas. Use life history attributes and environmental requirements of the reported nonindigenous species to evaluate traits of invaders. Understand the potential spread of invaders based on their habitat and environmental requirements. Understand importance of different vectors of introduction of nonindigenous species by region. The data in the Atlas of Nonindigenous Marine and Estuarine Species in the North Pacific (Lee and Reusser, 2012) are up-to-date as of June 2012. Updates to the PICES database were made in September 2012.

Report↗

USGS2007

Rotational seismology: AGU session, working group, and website

Introduction Although effects of rotational motions due to earthquakes have long been observed (e. g., Mallet, 1862), nevertheless Richter (1958, p. 213) stated that: 'Perfectly general motion would also involve rotations about three perpendicular axes, and three more instruments for these. Theory indicates, and observation confirms, that such rotations are negligible.' However, Richter provided no references for this claim. Seismology is based primarily on the observation and modeling of three-component translational ground motions. Nevertheless, theoretical seismologists (e.g., Aki and Richards, 1980, 2002) have argued for decades that the rotational part of ground motions should also be recorded. It is well known that standard seismometers are quite sensitive to rotations and therefore subject to rotation-induced errors. The paucity of observations of rotational motions is mainly the result of a lack, until recently, of affordable rotational sensors of sufficient resolution. Nevertheless, in the past decade, a number of authors have reported direct observations of rotational motions and rotations inferred from rigid-body rotations in short baseline accelerometer arrays, creating a burgeoning library of rotational data. For example, ring laser gyros in Germany and New Zealand have led to the first significant and consistent observations of rotational motions from distant earthquakes (Igel et al., 2005, 2007). A monograph on Earthquake Source Asymmetry, Structural Media and Rotation Effects was published recently as well by Teisseyre et al. (2006). Measurement of rotational motions has implications for: (1) recovering the complete ground-displacement history from seismometer recordings; (2) further constraining earthquake rupture properties; (3) extracting information about subsurface properties; and (4) providing additional ground motion information to earthquake engineers for seismic design. A special session on Rotational Motions in Seismology was convened by H. Igel, W.H.K. Lee, and M. Todorovska during the 2006 AGU Fall Meeting. The goal of this session was to discuss rotational sensors, observations, modeling, theoretical aspects, and potential applications of rotational ground motions. The session was accompanied by the inauguration of an International Working Group on Rotational Seismology (IWGoRS) which aims to promote investigations of all aspects of rotational motions in seismology and their implications for related fields such as earthquake engineering, geodesy, strong-motion seismology, and tectonics, as well as to share experience, data, software, and results in an open Web-based environment. The primary goal of this article is to make the Earth Science Community aware of the emergence of the field of rotational seismology.

Open-File Report↗

USGS2010

Ecological requirements for pallid sturgeon reproduction and recruitment in the Lower Missouri River: Annual report 2009

The Comprehensive Sturgeon Research Project is a multiyear, multiagency collaborative research framework developed to provide information to support pallid sturgeon recovery and Missouri River management decisions. The general Comprehensive Sturgeon Research Project strategy is to integrate field and laboratory studies of sturgeon reproductive ecology, habitat requirements, and physiology to produce a predictive understanding of sturgeon population dynamics. The project scope of work is developed annually with cooperating research partners and in collaboration with the U.S. Army Corps of Engineers, Missouri River Recovery-Integrated Science Program. The research consists of several interdependent and complementary research tasks engaging multiple disciplines that primarily address spawning as a probable limiting factor in reproduction and survival of the pallid sturgeon. The research is multifaceted and is designed to provide information needed for management decisions impacting habitat restoration, flow modification, and pallid sturgeon population augmentation on the Missouri River, and throughout the range of the species. Research activities and progress towards understanding of the species are reported to the U.S. Army Corps of Engineers annually. This annual report details the research effort and progress made by Comprehensive Sturgeon Research Project during 2009.

Open-File Report↗

USGS2003

Trends in concentrations of polychlorinated biphenyls in fish tissue from selected sites in the Delaware River basin in New Jersey, New York, and Pennsylvania, 1969-98

Polychlorinated biphenyl (PCB) concentrations in fish tissue collected during the 1990's from selected sites in the Delaware River Basin were compared with concentrations in fish tissue collected during 1969-88. Data collected by State and Federal agencies on concentrations in whole-body common carp ( Cyprinus carpio ) and white sucker ( Catostomus commersoni ), and edible portions of American eel ( Anguilla rostrata ), smallmouth bass ( Micropterus dolomieu ), and channel catfish ( Ictalurus punctatus ) during 1969-98 were compiled to define temporal trends in concentrations of PCBs in fish tissue from selected segments of the Delaware River, Lehigh River, Schuylkill River, and Brandywine Creek. The Delaware River in the vicinity of Trenton, New Jersey and Yardley, Pennsylvania (above the tidal influence) had the largest long-term data set among the sites considered for this study and was the only site with sufficient data for statistical analysis. A general pattern of decline in PCB concentrations during 1969-98 was apparent for this river segment. PCB concentrations in whole-body white sucker from this lower Delaware River segment declined during 1969-98 from a highest concentration of 7 micrograms per gram ( μ g/g, wet weight) in a sample collected during 1972 to 0.26 μ g/g (wet weight) in a sample collected during 1998. PCB concentration was negatively correlated with year (Spearman rank correlation -0.46, p < 0.08, n = 15); especially after removal of a sample from 1977 with an unusually low concentration (Spearman rank correlation -0.53, p = 0.05, n = 14). PCB concentrations in edible flesh of American eel declined during 1975-95, from a highest concentration of 3.8 μ g/g (wet weight) in a sample collected during 1976 to less than the reporting limit of 0.26 μ g/g (wet weight) in samples collected during 1993 and 1995. PCB concentrations in most samples (for species considered in this study) collected from the lower Delaware River exceeded the National Academy of Sciences and National Academy of Engineering (NAS/NAE) wildlife guideline level of 0.5 μ g/g during the 1970's and 1980's, and decreased to below this level during the 1990's. No samples of edible portions of game fish exceeded the U.S. Food and Drug Administration (FDA) tolerance level by the mid 1980's. However, the PCB concentration in a smallmouth bass fillet sample that was collected during 1998 (0.37 μ g/g) exceeded the Pennsylvania fish-consumption advisory level of 0.06 μ g/g, and the concentrations in whole-body common carp and white sucker collected during 1998 (1.10 μ g/g and 0.26 μ g/g, respectively) exceeded the New York State Department of Environmental Conservation wildlife criterion concentration of 0.11 μ g/g. (The concentration in carp also exceeded the 1973 NAS/NAE wildlife guideline concentration of 0.5 μ g/g.) Graphical analysis of PCB concentrations in whole white sucker and (or) edible portions of American eel from the upper Delaware River, lower Delaware River, middle Schuylkill River, and Brandywine Creek indicate a decline from the 1970's and (or) 1980's to the middle to late 1990's. Temporal trends in PCB concentrations in white sucker samples from the lower Lehigh and Schuylkill Rivers during 1979-98 are less clear; the PCB concentration (wet-weight basis) from a sample collected in 1998 from the lower Lehigh River was similar to that from a sample collected in 1979, and concentrations actually increased during 1982-98. Similarly, PCB concentrations in samples of white sucker and American eel from the lower Schuylkill River were highly variable over time.

New Jersey, New York, Pennsylvania↗

USGS2011

Evidence of volcanic and glacial activity in Chryse and Acidalia Planitiae, Mars

Chryse and Acidalia Planitiae show numerous examples of enigmatic landforms previously interpreted to have been influenced by a water/ice-rich geologic history. These landforms include giant polygons bounded by kilometer-scale arcuate troughs, bright pitted mounds, and mesa-like features. To investigate the significance of the last we have analyzed in detail the region between 60°N, 290°E and 10°N, 360°E utilizing HiRISE (High Resolution Imaging Science Experiment) images as well as regional-scale data for context. The mesas may be analogous to terrestrial tuyas (emergent sub-ice volcanoes), although definitive proof has not been identified. We also report on a blocky unit and associated landforms (drumlins, eskers, inverted valleys, kettle holes) consistent with ice-emplaced volcanic or volcano-sedimentary flows. The spatial association between tuya-like mesas, ice-emplaced flows, and further possible evidence of volcanism (deflated flow fronts, volcanic vents, columnar jointing, rootless cones), and an extensive fluid-rich substratum (giant polygons, bright mounds, rampart craters), allows for the possibility of glaciovolcanic activity in the region.Landforms indicative of glacial activity on Chryse/Acidalia suggest a paleoclimatic environment remarkably different from today's. Climate changes on Mars (driven by orbital/obliquity changes) or giant outflow channel activity could have resulted in ice-sheet-related landforms far from the current polar caps.

Icarus↗

USGS2005

Collection and analysis of high-resolution elevation data for the Lincoln Lidar Project, Lincoln, Nebraska, 2004

The Lincoln Lidar Project was a partnership developed between the U.S. Geological Survey National Center for Earth Resources Observations and Science (EROS), Lancaster County and the city of Lincoln, Nebraska. This project demonstrated a successful planning, collection, analysis and integration of high-resolution elevation information using Light Detection and Ranging, (Lidar) data. This report describes the partnership developed to collect local Lidar data and transform the data into information useable at local to national levels. This report specifically describes project planning, quality assurance, processing, transforming raw Lidar points to useable data layers, and visualizing and disseminating the raw and final products.

Nebraska↗

USGS2015

Porphyry copper assessment of northeast Asia: Far East Russia and northeasternmost China: Chapter W in Global mineral resource assessment

The U.S. Geological Survey assesses resources (mineral, energy, water, environmental, and biologic) at regional, national, and global scales to provide science in support of land management and decision making. Mineral resource assessments provide a synthesis of available information about where mineral deposits are known and suspected to be in the Earth’s crust, which commodities may be present, and estimates of amounts of resources in undiscovered deposits. A probabilistic mineral resource assessment of undiscovered resources associated with porphyry copper deposits in northeast Asia—composed mainly of Far East Russia and a small part of northeasternmost China—was completed as part of a global mineral resource assessment. Porphyry copper deposits are the main source of copper globally. Russia is an important source of copper, consistently ranking as 6th, 7th, or 8th in world production since 2000, and ranked 7th in 2014. Most of this production has been from magmatic copper-nickel-platinum-group element, volcanogenic massive sulfide, and sediment-hosted copper deposit types. The purpose of the assessment was to (1) compile a database of known deposits and significant prospects, (2) delineate permissive areas (tracts) for undiscovered porphyry copper deposits that may be present in the upper kilometer of the Earth’s crust, and (3) provide probabilistic estimates of amounts of copper (Cu), molybdenum (Mo), gold (Au), and silver (Ag) that could be contained in undiscovered porphyry copper deposits in the tracts. The assessment was completed by the U.S. Geological Survey in collaboration with geologists from the Russian Academy of Sciences and industry consultants. The database of known deposits, significant prospects, and prospects includes an inventory of mineral resources in two known porphyry copper deposits, as well as key characteristics derived from available exploration reports for 70 significant porphyry copper prospects and 86 other prospects. Resource and exploration and development activity are updated with information current through February 2013.

Scientific Investigations Report↗

USGS2012

Perils of correlating CUSUM-transformed variables to infer ecological relationships (Breton et al. 2006; Glibert 2010)

We comment on a nonstandard statistical treatment of time-series data first published by Breton et al. (2006) in Limnology and Oceanography and, more recently, used by Glibert (2010) in Reviews in Fisheries Science. In both papers, the authors make strong inferences about the underlying causes of population variability based on correlations between cumulative sum (CUSUM) transformations of organism abundances and environmental variables. Breton et al. (2006) reported correlations between CUSUM-transformed values of diatom biomass in Belgian coastal waters and the North Atlantic Oscillation, and between meteorological and hydrological variables. Each correlation of CUSUM-transformed variables was judged to be statistically significant. On the basis of these correlations, Breton et al. (2006) developed "the first evidence of synergy between climate and human-induced river-based nitrate inputs with respect to their effects on the magnitude of spring Phaeocystis colony blooms and their dominance over diatoms."

Limnology and Oceanography↗

USGS2012

Mars global digital dune database: MC-30

The Mars Global Digital Dune Database (MGD 3 ) provides data and describes the methodology used in creating the global database of moderate- to large-size dune fields on Mars. The database is being released in a series of U.S. Geological Survey Open-File Reports. The first report (Hayward and others, 2007) included dune fields from lat 65° N. to 65° S. ( http://pubs.usgs.gov/of/2007/1158/ ). The second report (Hayward and others, 2010) included dune fields from lat 60° N. to 90° N. ( http://pubs.usgs.gov/of/2010/1170/ ). This report encompasses ~75,000 km 2 of mapped dune fields from lat 60° to 90° S. The dune fields included in this global database were initially located using Mars Odyssey Thermal Emission Imaging System (THEMIS) Infrared (IR) images. In the previous two reports, some dune fields may have been unintentionally excluded for two reasons: (1) incomplete THEMIS IR (daytime) coverage may have caused us to exclude some moderate- to large-size dune fields or (2) resolution of THEMIS IR coverage (100 m/pixel) certainly caused us to exclude smaller dune fields. In this report, mapping is more complete. The Arizona State University THEMIS daytime IR mosaic provided complete IR coverage, and it is unlikely that we missed any large dune fields in the South Pole (SP) region. In addition, the increased availability of higher resolution images resulted in the inclusion of more small (~1 km 2 ) sand dune fields and sand patches. To maintain consistency with the previous releases, we have identified the sand features that would not have been included in earlier releases. While the moderate to large dune fields in MGD 3 are likely to constitute the largest compilation of sediment on the planet, we acknowledge that our database excludes numerous small dune fields and some moderate to large dune fields as well. Please note that the absence of mapped dune fields does not mean that dune fields do not exist and is not intended to imply a lack of saltating sand in other areas. Where availability and quality of THEMIS visible (VIS), Mars Orbiter Camera (MOC) narrow angle, Mars Express High Resolution Stereo Camera, or Mars Reconnaissance Orbiter Context Camera and High Resolution Imaging Science Experiment images allowed, we classified dunes and included some dune slipface measurements, which were derived from gross dune morphology and represent the approximate prevailing wind direction at the last time of significant dune modification. It was beyond the scope of this report to look at the detail needed to discern subtle dune modification. It was also beyond the scope of this report to measure all slipfaces. We attempted to include enough slipface measurements to represent the general circulation (as implied by gross dune morphology) and to give a sense of the complex nature of aeolian activity on Mars. The absence of slipface measurements in a given direction should not be taken as evidence that winds in that direction did not occur. When a dune field was located within a crater, the azimuth from crater centroid to dune field centroid was calculated, as another possible indicator of wind direction. Output from a general circulation model is also included. In addition to polygons locating dune fields, the database includes ~700 of the THEMIS VIS and MOC images that were used to build the database.

Open-File Report↗