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USGS1999

The Scientific Assessment and Strategy Team

The flood of 1993 in the Upper Mississippi River Basin caused widespread devastation. The human and economic costs were high. The total flood and other related damage estimates were in the $10 billion to $16 billion range, with total Federal expenditures in excess of $5.4 billion. In response to the effects of the flood of 1993, the White House established the Scientific Assessment and Strategy Team (SAST) on November 24, 1993. The SAST?s goals are to provide scientific advice and assistance to policymakers and officials responsible for flood recovery and river basin management in the Upper Mississippi River Basin and to prepare a data base to support those goals.

Fact Sheet↗

USGS2001

Borehole P- and S-wave velocity at thirteen stations in Southern California

The U.S. Geological Survey (USGS), as part of a program to acquire seismic velocity data at locations of strong-ground motion in earthquakes (e.g., Gibbs et al., 2000), has investigated thirteen additional sites in the Southern California region. Of the thirteen sites, twelve are in the vicinity of Whittier, California, and one is located in San Bernardino, California. Several deployments of temporary seismographs were made after the Whittier Narrows, California earthquake of 1 October 1987 (Mueller et al., 1988). A deployment, between 2 October and 9 November 1987, was the motivation for selection of six of the drill sites. Temporary portable seismographs at Hoover School (HOO), Lincoln School (LIN), Corps of Engineers Station (NAR), Olive Junior High School (OLV), Santa Anita Golf Course (SAG), and Southwestern Academy (SWA) recorded significant aftershock data. These portable sites, with the exception of Santa Anita Golf Course, were co-sited with strong-motion recorders. Stations at HOO, Lincoln School Whittier (WLB), Saint Paul High School (STP), Alisos Adult School (EXC), Cerritos College Gymnasium (CGM), Cerritos College Physical Science Building (CPS), and Cerritos College Police Building (CPB) were part of an array of digital strong-motion stations deployed from "bedrock" in Whittier to near the deepest part of the Los Angeles basin in Norwalk. Although development and siting of this new array (partially installed at the time of this writing) was generally motivated by the Whittier Narrows earthquake, these new sites (with the exception of HOO) were not part of any Whittier Narrows aftershock deployments. A similar new digital strong-motion site was installed at the San Bernardino Fire Station during the same time frame. Velocity data were obtained to depths of about 90 meters at two sites, 30 meters at seven sites, and 18 to 25 meters at four sites. Lithology data from the analysis of cuttings and samples was obtained from the two 90-meter deep holes and from five of the shallower holes to supplement the velocity interpretation. The two 90-meter boreholes (SB1, CPB) have been instrumented with borehole seismometers for continuous monitoring of earthquake activity (Rogers et al., 1998). No drill samples or cuttings were obtained from the other six sites, but driller's logs were scanned for major changes noted there. The velocity models at those sites were interpreted using only the measured data and major changes in the driller's log as noted above. The sites are shown in Figure 1 and listed in Table 1, which gives references to information regarding the strong-motion data. Several hundred strong-motion records of the main-shock were written by this moderate size earthquake (ML = 5.9), making it important from a scientific and engineering prospective (Brady et al., 1988; Shakal et al., 1988).

California↗

USGS2003

Location and age database for selected foraminifer samples collected by Exxon Petroleum geologists in California

Most of the geologic maps published for central California before 1960 were made without the benefit of age determinations from microfossils. The ages of Cretaceous and Tertiary rocks in the mostly poorly exposed and structurally complex sedimentary rocks represented in the Coast Ranges are critical in determining stratigraphic succession or lack of it, and in determining whether the juxtaposition of similar appearing but different age formations means a fault is present. Since the 1930’s, at least, oil company geologists have used microfossils to assist them in geologic mapping and in determining the environments of deposition of the sediment containing the microfossils. This information has been so confidential that some companies even coded the names of foraminifers to prevent disclosure. In the past 20 years, however, the attitude of petroleum companies about this information has changed, and many of the formerly confidential materials and reports are now available. We report here on 1,964 Exxon foraminifer samples mostly from surface localities in the San Francisco Bay region, and elsewhere in California. Most but not all the samples were plotted on U. S. Geological Survey (USGS) 7.5’ topographic maps or on obsolete USGS 15’ maps. The information from the slides can be used to update geologic maps prepared without the benefit of microfossil data, to analyze the depth and temperature of ocean water covering parts of California during the Mesozoic and Cenozoic Eras, and for solving nomenclature and other scientific problems. A similar report on more than 30,000 slides for surface samples collected by Chevron geologists has been released (Brabb and Parker, 2003), and another report provides information on slides for more than 2000 oil test wells in Northern California (Brabb, Powell, and Brocher, 2001).

California↗

USGS2012

Summary of bird-survey and banding results at W.L. Finley National Wildlife Refuge, 1998-2008

With some of the best remaining examples of oak habitats in the Willamette Valley, the Willamette Valley National Wildlife Refuge Complex (WVNWRC) has been implementing restoration efforts to reverse the successional trend towards Douglas-fir and maple that is threatening existing oak woodlands. The restoration work has been considered a model for other public and private efforts within the Willamette Valley, and has been showcased through the Oregon Oak Communities Working Group (http://www.oregonoaks.org). Although many oak restoration projects have been initiated over the last several years, and grant recipients typically identify wildlife species that are likely to benefit from their project, measures of success have not included the actual response of wildlife, such as a change in the probability of species occurrence or abundance. Monitoring in the WVNWRC has so far been limited to vegetative and structural changes within the plant community. Hagar and Stern (2001) identified bird species occurring in Willamette Valley oak woodlands that might be expected to benefit from such restoration efforts, including an endemic subspecies of the White-breasted Nuthatch (see Appendix 1 for scientific names of bird and plant species listed in this document), and the Acorn Woodpecker, both of which are species of concern in Oregon. However, empirical data documenting responses of bird assemblages to restoration actions are needed. The goal of this study was to document the effects of a restoration project in an Oregon White Oak woodland on Pigeon Butte in the W.L. Finley National Wildlife Refuge. Restoration treatments on Pigeon Butte include the removal of shade-tolerant tree species (primarily big-leaf maple and Douglas-fir) to reduce competition with oak trees and to return the stand to a more open structure. The objectives of this ongoing study are to compare abundance, survival, and productivity of diurnal songbird species before and after application of these restoration treatments. Monitoring these vital rates will provide crucial information about the effects of management on survival and productivity (DeSante and Rosenberg, 1998). Therefore, a constant-effort mist-netting project was continued in 2007 and 2008 that had previously collected songbird demographic data at Pigeon Butte from 1998 to 2002. Point-count surveys were conducted in the woodland to build on historical data available for the site (Anderson, 1970; Hagar and Stern, 2001). The data reported here represent 5 years of point count surveys and 6 years of banding before restoration treatment, but only one post-treatment sampling season. Continued monitoring of the bird population is recommended to determine both short-term effects and long-term trends following the habitat alterations that result from restoration treatment.

Oregon↗

USGS1989

GEOS seismograms recorded for aftershocks of the earthquakes of December 7, 1988, near Spitak, Armenia SSR, during the time period 26 December 1988 14:00 through 29 December 1988 (UTC)

The earthquakes of December 7, 1988, near Spitak, Armenia SSR, serve as another grim reminder of the serious hazard that earthquakes pose throughout the world. We extend our heartfelt sympathies to the families of the earthquake victims and intend that our cooperative scientific endeavours will help reduce losses in future earthquakes. Only through a better understanding of earthquake hazards can earthquake losses be reduced for all peoples in seismically active regions of the world. The tragic consequences of these earthquakes remind scientists and public officials alike of their urgent responsibilities to understand and mitigate the effects of earthquakes. On behalf of the U.S. Geological Survey, I would like to express appreciation to our Soviet colleagues for their kind invitation to participate in joint scientific and engineering studies. Without their cooperation and generous assistance, the conduct of these studies would not have been possible. This report provides seismologic and geologic data collected during the time period December 21, 1988, through February 2, 1989. These data are presented in their entirety to expedite analysis of the data set for inferences regarding hazard mitigation actions, applicable not only in Armenia but other regions of the world exposed to high seismic risk.

Open-File Report↗

USGS1989

GEOS seismograms recorded for aftershocks of the earthquakes of December 7, 1988, near Spitak, Armenia SSR, during the time period 3 January 1989 through 2 February 1988 (UTC)

Open-File Report↗

USGS2003

Understanding climatic impacts, vulnerabilities, and adaptation in the United States: Building a capacity for assessment

Based on the experience of the U.S. National Assessment, we propose a program of research and analysis to advance capability for assessment of climate impacts, vulnerabilities, and adaptation options. We identify specific priorities for scientific research on the responses of ecological and socioeconomic systems to climate and other stresses; for improvement in the climatic inputs to impact assessments; and for further development of assessment methods to improve their practical utility to decision-makers. Finally, we propose a new institutional model for assessment, based principally on regional efforts that integrate observations, research, data, applications, and assessment on climate and linked environmental-change issues. The proposed program will require effective collaboration between scientists, resource managers, and other stakeholders, all of whose expertise is needed to define and prioritize key regional issues, characterize relevant uncertainties, and assess potential responses. While both scientifically and organizationally challenging, such an integrated program holds the best promise of advancing our capacity to manage resources and the economy adaptively under a changing climate.

Climatic Change↗

USGS2011

SAFOD Phase III Core sampling and data management at the Gulf Coast repository

[No abstract available]

Scientific Drilling↗

USGS2014

Estimates of groundwater recharge rates and sources in the East Mountain area, Eastern Bernalillo County, New Mexico, 2005-12

The U.S. Geological Survey, in cooperation with the Bernalillo County Public Works Division, has conducted a monitoring program in the East Mountain area of eastern Bernalillo County, New Mexico, since 2000 to better define the hydrogeologic characteristics of the East Mountain area and to provide scientific information that will assist in the sustainable management of water resources. This report presents estimates of groundwater recharge to the aquifers that supply water to a network of springs that discharged within the East Mountain area of eastern Bernalillo County during 2005–12. Chloride concentration, the mass ratio of chloride to bromide, and the stable isotope ratios of hydrogen and oxygen were used to estimate annual groundwater recharge rates and to identify the sources and timing of recharge to the aquifers in the East Mountain area. Groundwater recharge rates were estimated by using a chloride mass-balance (CMB) method applied to data from selected springs located in the study area. Eleven springs and four downgradient monitoring wells were sampled for this study. On the basis of chloride concentrations and the mass ratio of chloride to bromide, eight of the eleven sampled springs are considered representative of dilute groundwater recharged by meteoric water in the Sandia Mountains. Eight of the eleven springs sampled as part of this investigation are considered representative of dilute groundwater not influenced by nonmeteoric chloride sources on the basis of analysis of chloride concentrations and the mass ratio of chloride to bromide. Chloride concentrations at three of the sampled springs were likely affected by nonmeteoric chloride sources. Results of CMB calculations for the eight springs with Cl:Br ratios and chloride concentrations within the range of dilute groundwater (not influenced by nonmeteoric chloride sources) indicated that between about 5.5 and 23 percent of annual precipitation recharges the groundwater system. The variation in estimated recharge rates indicated that the mechanisms for recharge and groundwater movement in the East Mountain area are complex and that factors such as climate variability, the extent and interconnection of structural features such as faults and fractures, and potential solution enhancement of the aquifers all play important roles in the rates and timing of recharge. Stable isotope data from springs and snowpacks sampled in the East Mountain area were compared with local, regional, and global meteoric water lines and were analyzed along with values representing the stable isotope composition of winter precipitation and summer monsoonal rains. Results of the stable isotope analysis from springs in this study suggested that winter precipitation is the primary source of groundwater recharge to the aquifers supplying the springs, but there is a component of more isotopically enriched precipitation being recharged as well, likely from summer monsoonal rains. Specific conductance, groundwater-level hydrographs, snowpack chemistry, and snow-water equivalent data were used to inform the analyses and corroborate the findings of the CMB and stable isotope results.

New Mexico↗

USGS2012

Creation of digital contours that approach the characteristics of cartographic contours

The capability to easily create digital contours using commercial off-the-shelf (COTS) software has existed for decades. Out-of-the-box raw contours are suitable for many scientific applications without pre- or post-processing; however, cartographic applications typically require additional improvements. For example, raw contours generally require smoothing before placement on a map. Cartographic contours must also conform to certain spatial/logical rules; for example, contours may not cross waterbodies. The objective was to create contours that match as closely as possible the cartographic contours produced by manual methods on the 1:24,000-scale, 7.5-minute Topographic Map series. This report outlines the basic approach, describes a variety of problems that were encountered, and discusses solutions. Many of the challenges described herein were the result of imperfect input raster elevation data and the requirement to have the contours integrated with hydrographic features from the National Hydrography Dataset (NHD).

Scientific Investigations Report↗

USGS2014

Wave-driven sediment mobilization on a storm-controlled continental shelf (Northwest Iberia)

Seafloor sediment mobilization on the inner Northwest Iberian continental shelf is caused largely by ocean surface waves. The temporal and spatial variability in the wave height, wave period, and wave direction has a profound effect on local sediment mobilization, leading to distinct sediment mobilization scenarios. Six grain-size specific sediment mobilization scenarios, representing seasonal average and storm conditions, were simulated with a physics-based numerical model. Model inputs included meteorological and oceanographic data in conjunction with seafloor grain-size and the shelf bathymetric data. The results show distinct seasonal variations, most importantly in wave height, leading to sediment mobilization, specifically on the inner shelf shallower than 30 m water depth where up to 49% of the shelf area is mobilized. Medium to severe storm events are modeled to mobilize up to 89% of the shelf area above 150 m water depth. The frequency of each of these seasonal and storm-related sediment mobilization scenarios is addressed using a decade of meteorological and oceanographic data. The temporal and spatial patterns of the modeled sediment mobilization scenarios are discussed in the context of existing geological and environmental processes and conditions to assist scientific, industrial and environmental efforts that are directly affected by sediment mobilization. Examples, where sediment mobilization plays a vital role, include seafloor nutrient advection, recurrent arrival of oil from oil-spill-laden seafloor sediment, and bottom trawling impacts.

Journal of Marine Systems↗

USGS2014

Discrete-storm water-table fluctuation method to estimate episodic recharge.

We have developed a method to identify and quantify recharge episodes, along with their associated infiltration-related inputs, by a consistent, systematic procedure. Our algorithm partitions a time series of water levels into discrete recharge episodes and intervals of no episodic recharge. It correlates each recharge episode with a specific interval of rainfall, so storm characteristics such as intensity and duration can be associated with the amount of recharge that results. To be useful in humid climates, the algorithm evaluates the separability of events, so that those whose recharge cannot be associated with a single storm can be appropriately lumped together. Elements of this method that are subject to subjectivity in the application of hydrologic judgment are values of lag time, fluctuation tolerance, and master recession parameters. Because these are determined once for a given site, they do not contribute subjective influences affecting episode-to-episode comparisons. By centralizing the elements requiring scientific judgment, our method facilitates such comparisons by keeping the most subjective elements openly apparent, making it easy to maintain consistency. If applied to a period of data long enough to include recharge episodes with broadly diverse characteristics, the method has value for predicting how climatic alterations in the distribution of storm intensities and seasonal duration may affect recharge.

Groundwater↗

USGS2009

The ecological limits of hydrologic alteration (ELOHA): A new framework for developing regional environmental flow standards

The flow regime is a primary determinant of the structure and function of aquatic and riparian ecosystems for streams and rivers. Hydrologic alteration has impaired riverine ecosystems on a global scale, and the pace and intensity of human development greatly exceeds the ability of scientists to assess the effects on a river-by-river basis. Current scientific understanding of hydrologic controls on riverine ecosystems and experience gained from individual river studies support development of environmental flow standards at the regional scale. 2. This paper presents a consensus view from a group of international scientists on a new framework for assessing environmental flow needs for many streams and rivers simultaneously to foster development and implementation of environmental flow standards at the regional scale. This framework, the ecological limits of hydrologic alteration (ELOHA), is a synthesis of a number of existing hydrologic techniques and environmental flow methods that are currently being used to various degrees and that can support comprehensive regional flow management. The flexible approach allows scientists, water-resource managers and stakeholders to analyse and synthesise available scientific information into ecologically based and socially acceptable goals and standards for management of environmental flows. 3. The ELOHA framework includes the synthesis of existing hydrologic and ecological databases from many rivers within a user-defined region to develop scientifically defensible and empirically testable relationships between flow alteration and ecological responses. These relationships serve as the basis for the societally driven process of developing regional flow standards. This is to be achieved by first using hydrologic modelling to build a 'hydrologic foundation' of baseline and current hydrographs for stream and river segments throughout the region. Second, using a set of ecologically relevant flow variables, river segments within the region are classified into a few distinctive flow regime types that are expected to have different ecological characteristics. These river types can be further subclassified according to important geomorphic features that define hydraulic habitat features. Third, the deviation of current-condition flows from baseline-condition flow is determined. Fourth, flow alteration-ecological response relationships are developed for each river type, based on a combination of existing hydroecological literature, expert knowledge and field studies across gradients of hydrologic alteration. 4. Scientific uncertainty will exist in the flow alteration-ecological response relationships, in part because of the confounding of hydrologic alteration with other important environmental determinants of river ecosystem condition (e.g. temperature). Application of the ELOHA framework should therefore occur in a consensus context where stakeholders and decision-makers explicitly evaluate acceptable risk as a balance between the perceived value of the ecological goals, the economic costs involved and the scientific uncertainties in functional relationships between ecological responses and flow alteration. 5. The ELOHA framework also should proceed in an adaptive management context, where collection of monitoring data or targeted field sampling data allows for testing of the proposed flow alteration-ecological response relationships. This empirical validation process allows for a fine-tuning of environmental flow management targets. The ELOHA framework can be used both to guide basic research in hydroecology and to further implementation of more comprehensive environmental flow management of freshwater sustainability on a global scale. ?? 2009 Blackwell Publishing Ltd.

Freshwater Biology↗

USGS2004

The elusive baseline of marine disease: Are diseases in ocean ecosystems increasing?

Disease outbreaks alter the structure and function of marine ecosystems, directly affecting vertebrates (mammals, turtles, fish), invertebrates (corals, crustaceans, echinoderms), and plants (seagrasses). Previous studies suggest a recent increase in marine disease. However, lack of baseline data in most communities prevents a direct test of this hypothesis. We developed a proxy to evaluate a prediction of the increasing disease hypothesis: the proportion of scientific publications reporting disease increased in recent decades. This represents, to our knowledge, the first quantitative use of normalized trends in the literature to investigate an ecological hypothesis. We searched a literature database for reports of parasites and disease (hereafter “disease”) in nine marine taxonomic groups from 1970 to 2001. Reports, normalized for research effort, increased in turtles, corals, mammals, urchins, and molluscs. No significant trends were detected for seagrasses, decapods, or sharks/rays (though disease occurred in these groups). Counter to the prediction, disease reports decreased in fishes. Formulating effective resource management policy requires understanding the basis and timing of marine disease events. Why disease outbreaks increased in some groups but not in others should be a priority for future investigation. The increase in several groups lends urgency to understanding disease dynamics, particularly since few viable options currently exist to mitigate disease in the oceans.

PLoS Biology↗

USGS1999

National Water-Quality Assessment Program: Great Salt Lake basins study unit

The Great Salt Lake Basins NAWQA study will increase the scientific understanding of the factors that influence surface- and ground-water quality. This information will benefit water-resources managers that need, but often lack, the data required to implement effective water-quality management actions and evaluate long-term changes in water quality.

Idaho, Utah, Wyoming↗

USGS2013

Digital data from the Great Sand Dunes airborne gravity gradient survey, south-central Colorado

This report contains digital data and supporting explanatory files describing data types, data formats, and survey procedures for a high-resolution airborne gravity gradient (AGG) survey at Great Sand Dunes National Park, Alamosa and Saguache Counties, south-central Colorado. In the San Luis Valley, the Great Sand Dunes survey covers a large part of Great Sand Dunes National Park and Preserve. The data described were collected from a high-resolution AGG survey flown in February 2012, by Fugro Airborne Surveys Corp., on contract to the U.S. Geological Survey. Scientific objectives of the AGG survey are to investigate the subsurface structural framework that may influence groundwater hydrology and seismic hazards, and to investigate AGG methods and resolution using different flight specifications. Funding was provided by an airborne geophysics training program of the U.S. Department of Defense's Task Force for Business & Stability Operations.

Colorado↗

USGS2005

Results of land cover change detection analysis in and around Cordillera Azul National Park, Peru

The first product of the Optimizing Design and Management of Protected Areas for Conservation Project is a land cover change detection analysis based on Landsat thematic mapper (TM) and enhanced thematic mapper plus (ETM+) imagery collected at intervals between 1989 and 2002. The goal of this analysis was to quantify and analyze patterns of forest clearing, land conversion, and other disturbances in and around the Cordillera Azul National Park in Peru. After removing clouds and cloud shadows from the imagery using a series of automatic and manual processes, a Tasseled Cap Transformation was used to detect pixels of high reflectance, which were classified as bare ground and areas of likely forest clearing. Results showed a slow but steady increase in cleared ground prior to 1999 and a rapid and increasing conversion rate after that time. The highest concentrations of clearings have spread upward from the western border of the study area on the Huallaga River. To date, most disturbances have taken place in the buffer zone around the park, not within it, but the data show dense clearings occurring closer to the park border each year.

Scientific Investigations Map↗

USGS2014

Vegetation types in coastal Louisiana in 2013

During the summer of 2013, the U.S. Geological Survey, Louisiana State University, University of Louisiana at Lafayette, and the Louisiana Department of Wildlife and Fisheries Coastal and Nongame Resources Division jointly completed an aerial survey to collect data on 2013 vegetation types in coastal Louisiana. Plant species were listed and their abundance classified. On the basis of species composition and abundance, each marsh sampling station was assigned a marsh type: fresh, intermediate, brackish, or saline (saltwater) marsh. The current map presents the data collected in this effort.

Louisiana↗