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At least 343 records · Page 19Linked to original sources

USGS2004

Distribution and abundance of pelagic fish in Lake Powell, Utah, and Lake Mead, Arizona-Nevada

Pelagic fish communities (waters with depths >20 m) of Lakes Powell and Mead were examined quarterly from 1995 to 1998 using vertical gill nets and a scientific echosounder. Nets captured a total of 449 fish consisting of striped bass (57%/45% [Lake Powell/Lake Mead]), threadfin shad (24%/50%), common carp (15%/4%), walleye (3%), channel catfish (2%), and rainbow trout (<1%). Each reservoir contained concentrations of pelagic species separated by expanses of habitat with few fish (<10 kg·ha⁻¹). Reservoirs experienced dramatic seasonal and annual fluctuations in pelagic biomass. Lake Powell's biomass peaked at the Colorado River at 709.7 (± 46.5) kg · ha⁻¹ and Lake Mead's reached 291.9 (± 58.2) kg · ha⁻¹ at Las Vegas Wash. These locations supported estimated fish densities of 124,668 fish · ha⁻¹ and 15,131 fish · ha⁻¹, respectively. Maximum reservoir biomass peaked in August 1996, with Lake Powell supporting 10,852,738 ± 5,195,556 kg (27.6 × 10⁻ fish) and Lake Mead 1,926,697 ± 892.994 kg (10.8 × 10⁻ fish). Biomass ebbed in May (1996 and 1997), when Lake Mead supported 65% (296,736 kg vs. 453,097 kg) and 62% (101,016 kg vs. 162,262 kg) of biomass levels found in Lake Powell.

Arizona, Nevada, Utah↗

USGS2006

Mission in the works promises precise global topographic data

Significant deficiencies in the quality of today's topographic data severely limit scientific applications. Very few available data sets meet the stringent requirements of 10–30 m for global digital topography and 5 m or better vertical accuracy, and existing satellite systems are unlikely to fulfill these requirements. The Joint Topographic Science Working Group, appointed by NASA and the Italian Space Agency, concluded that radar interferometry coupled with a laser altimeter would be the most promising approach for improving data quality. By providing its own illumination at a wavelength Ion g enough to (e.g., λ = 25 cm) to penetrate clouds and rain, the interferometer would provide a global, uniform high-quality topographic data set. One mission under study, TOPSAT, is well positioned to fill this niche and promises to pave the way toward a more standardized and precise topographic database. TOPSAT would be an international mission, designed to make use of recent technology advances in such programs as NASA's New Millennium. It could be ready to launch by the end of this decade.

Eos, Transactions, American Geophysical Union↗

USGS2017

Peak discharge, flood frequency, and peak stage of floods on Big Cottonwood Creek at U.S. Highway 50 near Coaldale, Colorado, and Fountain Creek below U.S. Highway 24 in Colorado Springs, Colorado, 2016

The U.S. Geological Survey (USGS), in cooperation with the Colorado Department of Transportation, determined the peak discharge, annual exceedance probability (flood frequency), and peak stage of two floods that took place on Big Cottonwood Creek at U.S. Highway 50 near Coaldale, Colorado (hereafter referred to as “Big Cottonwood Creek site”), on August 23, 2016, and on Fountain Creek below U.S. Highway 24 in Colorado Springs, Colorado (hereafter referred to as “Fountain Creek site”), on August 29, 2016. A one-dimensional hydraulic model was used to estimate the peak discharge. To define the flood frequency of each flood, peak-streamflow regional-regression equations or statistical analyses of USGS streamgage records were used to estimate annual exceedance probability of the peak discharge. A survey of the high-water mark profile was used to determine the peak stage, and the limitations and accuracy of each component also are presented in this report. Collection and computation of flood data, such as peak discharge, annual exceedance probability, and peak stage at structures critical to Colorado’s infrastructure are an important addition to the flood data collected annually by the USGS. The peak discharge of the August 23, 2016, flood at the Big Cottonwood Creek site was 917 cubic feet per second (ft 3/s ) with a measurement quality of poor (uncertainty plus or minus 25 percent or greater). The peak discharge of the August 29, 2016, flood at the Fountain Creek site was 5,970 ft 3/s with a measurement quality of poor (uncertainty plus or minus 25 percent or greater). The August 23, 2016, flood at the Big Cottonwood Creek site had an annual exceedance probability of less than 0.01 (return period greater than the 100-year flood) and had an annual exceedance probability of greater than 0.005 (return period less than the 200-year flood). The August 23, 2016, flood event was caused by a precipitation event having an annual exceedance probability of 1.0 (return period of 1 year, or the 1-year storm), which is a statistically common (high probability) storm. The Big Cottonwood Creek site is downstream from the Hayden Pass Fire burn area, which dramatically altered the hydrology of the watershed and caused this statistically rare (low probability) flood from a statistically common (high probability) storm. The peak flood stage at the cross section closest to the U.S. Highway 50 culvert was 6,438.32 feet (ft) above the North American Datum of 1988 (NAVD 88). The August 29, 2016, flood at the Fountain Creek site had an estimated annual exceedance probability of 0.5505 (return period equal to the 1.8-year flood). The August 29, 2016, flood event was caused by a precipitation event having an annual exceedance probability of 1.0 (return period of 1 year, or the 1-year storm). The peak stage during this flood at the cross section closest to the U.S. Highway 24 bridge was 5,832.89 ft (NAVD 88). Slope-area indirect discharge measurements were carried out at the Big Cottonwood Creek and Fountain Creek sites to estimate peak discharge of the August 23, 2016, flood and August 29, 2016, flood, respectively. The USGS computer program Slope-Area Computation Graphical User Interface was used to compute the peak discharge by adding the surveyed cross sections with Manning roughness coefficient assignments to the high-water marks. The Manning roughness coefficients for each cross section were estimated in the field using the Cowan method.

Colorado↗

USGS2013

Metal prices in the United States through 2010

This report, which updates and revises the U.S. Geological Survey (USGS) (1999) publication, “Metal Prices in the United States Through 1998,” presents an extended price history for a wide range of metals available in a single document. Such information can be useful for the analysis of mineral commodity issues, as well as for other purposes. The chapter for each mineral commodity includes a graph of annual current and constant dollar prices for 1970 through 2010, where available; a list of significant events that affected prices; a brief discussion of the metal and its history; and one or more tables that list current dollar prices. In some cases, the metal prices presented herein are for some alternative form of an element or, instead of a price, a value, such as the value for an import as appraised by the U.S. Customs Service. Also included are the prices for steel, steel scrap, and iron ore—steel because of its importance to the elements used to alloy with it, and steel scrap and iron ore because of their use in steelmaking. A few minor metals, such as calcium, potassium, sodium, strontium, and thorium, for which price histories were insufficient, were excluded. The annual prices given may be averages for the year, yearend prices, or some other price as appropriate for a particular commodity. Certain trade journals have been the source of much of this price information—American Metal Market, ICIS Chemical Business, Engineering and Mining Journal, Industrial Minerals, Metal Bulletin, Mining Journal, Platts Metals Week, Roskill Information Services Ltd. commodity reports, and Ryan’s Notes. Price information also is available in minerals information publications of the USGS (1880–1925, 1996–present) and the U.S. Bureau of Mines (1926–95), such as Mineral Commodity Summaries, Mineral Facts and Problems, Mineral Industry Surveys, and Minerals Yearbook. In addition to prices themselves, these journals and publications contain information relevant to prices, which has been helpful in the preparation of this publication. Prices in this report have been graphed in 1992 constant dollars to show the effects of inflation as measured by the U.S. Bureau of Labor Statistics Consumer Price Index for All Urban Consumers, a widely used measure of overall inflation in the United States. These prices are not tabulated, but a table of the deflators used is given in an appendix. Constant dollar prices can be used to show how prices that producers receive would have less purchasing power.

Scientific Investigations Report↗

USGS2018

Thermal tolerance limits of the Chinese mystery snail (Bellamya chinensis): Implications for management

The Chinese mystery snail, Bellamya chinensis (Gray, 1834) is a gastropod native to East Asia and is considered an invasive species in North America where its impacts on native species and ecosystems are not well understood. Scientific literature describing its biology and life history are sparse. Thermal tolerance limits, or the maximum and minimum temperature under which a species can survive, are key to identifying the potential geographical range of a species. The ability of managers to control invasive species is directly impacted by the thermal tolerance limits of a species. We attempted to identify the thermal tolerance limits of B. chinensis in a laboratory setting. Using a random sampling design, we exposed groups of wild-caught B. chinensis to either extreme high or low temperature treatments. We identified the upper temperature tolerance limit as between 40 and 45 °C. This result indicates some hot water management techniques may successfully prevent spread of B. chinensis among waterways. Despite exposing B. chinensis to freezing temperatures for extended periods of time we did not identify a lower temperature limit. Identifying the thermal tolerance limits of this and other invasive species informs predictions of range expansion and identification of potential prevention efforts.

American Malacological Bulletin↗

USGS2020

Waterfowl occurrence and residence time as indicators of H5 and H7 avian influenza in North American Poultry

Avian inﬂuenza (AI) affects wild aquatic birds and poses hazards to human health, food security, and wildlife conservation globally. Accordingly, there is a recognized need for new methods and tools to help quantify the dynamic interaction between wild bird hosts and commercial poultry. Using satellite-marked waterfowl, we applied Bayesian joint hierarchical modeling to concurrently model species distributions, residency times, migration timing, and disease occurrence probability under an integrated animal movement and disease distribution modeling framework. Our results indicate that migratory waterfowl are positively related to AI occurrence over North America such that as waterfowl occurrence probability or residence time increase at a given location, so too does the chance of a commercial poultry AI outbreak. Analyses also suggest that AI occurrence probability is greatest during our observed waterfowl northward migration, and less during the southward migration. Methodologically, we found that when modeling disparate facets of disease systems at the wildlife-agriculture interface, it is essential that multiscale spatial patterns be addressed to avoid mistakenly inferring a disease process or disease-environment relationship from a pattern evaluated at the improper spatial scale. The study offers important insights into migratory waterfowl ecology and AI disease dynamics that aid in better preparing for future outbreaks.

Scientific Reports↗

USGS2013

Annual exceedance probabilities of the peak discharges of 2011 at streamgages in Vermont and selected streamgages in New Hampshire, western Massachusetts, and northeastern New York

The U.S. Geological Survey, in cooperation with the Federal Emergency Management Agency, determined annual exceedance probabilities for peak discharges occurring during the 2011 water year (October 1 to September 30) at streamgages in Vermont and selected streamgages in New Hampshire, western Massachusetts, and northeastern New York. This report presents the 2011 water year peak discharges at 145 streamgages in the study area and provides the results of the analyses of the 50-, 20-, 10-, 4-, 2-, 1-, and 0.2-percent annual exceedance probability discharges at 135 of the 145 streamgages. The annual exceedance probabilities for the 2011 water year peak discharges also are presented. Snowmelt and near record rainfall led to flooding across northern Vermont on April 27 and 28, 2011. At three streamgages with more than 10 years of record, the April rain event resulted in the peak discharge of record. At seven streamgages, the peak discharge resulting from this event had an annual exceedance probability less than or equal to 1 percent. In early May 2011, new peak stage records were set at two Lake Champlain gages with more than 100 years of record. At the Lake Champlain at Burlington, Vermont, gage, the water surface reached 102.79 feet (ft) (North American Vertical Datum of 1988 (NAVD 88)) on May 6, 2011, and at the Richelieu River (Lake Champlain) at Rouses Point, New York, gage, the water surface reached 102.75 ft NAVD 88. Record-breaking rainfall in late May produced additional flooding across northern Vermont on May 26 and 27, 2011. Four streamgages in northwestern Vermont recorded peak-of-record discharges as a result of this flooding. At three streamgages, the peak discharges from this event had an annual exceedance probability less than or equal to 1 percent. From August 28 to 29, 2011, Tropical Storm Irene delivered rainfall totals ranging from about 3 to more than 10 inches, which resulted in extensive flooding and new period-of-record peak discharges at 37 streamgages in the study area. The peak discharges as a result of Tropical Storm Irene had an annual exceedance probability of less than or equal to 1 percent at 36 streamgages. At 11 of these 36 streamgages, the annual exceedance probability of the peak discharges was less than or equal to 0.2 percent.

Massachusetts;New Hampshire;New York;Vermont↗

USGS2015

Flood-inundation Maps for the Deerfield River, Franklin County, Massachusetts, from the Confluence with the Cold River Tributary to the Connecticut River

The U.S. Geological Survey developed flood elevations in cooperation with the Federal Emergency Management Agency for a 30-mile reach of the Deerfield River from the confluence of the Cold River tributary to the Connecticut River in the towns of Charlemont, Buckland, Shelburne, Conway, Deerfield, and Greenfield in Franklin County, Massachusetts to assist land owners, and emergency management workers prepare for and recover from floods. Peak flows with 50-, 20-, 10-, 4-, 2-, 1-, 0.5-, and 0.2-percent annual exceedance probabilities were computed for the reach from updated flood-frequency analyses. These peak flows were routed through a one-dimensional step-backwater hydraulic model to obtain the corresponding peak water-surface elevations and to place the tropical storm Irene flood of August 28, 2011 into historical context. The hydraulic model was calibrated by using current [2015] stage-discharge relations at two U.S. Geological Survey streamgages in the study reach—Deerfield River at Charlemont, MA (01168500) and Deerfield River near West Deerfield, MA (01170000)—and from documented high-water marks from the tropical storm Irene flood, which had between a 1- and 0.2-percent AEP. The hydraulic model was used to compute water-surface profiles for flood stages referenced to the two streamgages. Two sets of flood-inundation map libraries were created from the modeled profiles. The library for the upstream, western portion of the modeled reach is 9.1 miles long, extends from just downstream of the confluence of the Deerfield River with the Cold River to just upstream of the confluence with Clesson Brook, and is calibrated to the Deerfield River at Charlemont, MA streamgage. The library for the downstream, eastern portion of the modeled reach is 8.9 miles long, extends from just downstream of the confluence of the Deerfield River with the South River to just upstream of the confluence with the Green River, and is calibrated to the Deerfield River near West Deerfield streamgage. Stages for mapped profiles of the upstream reach range from 8.7 feet (ft) at the local datum (525.6 ft when converted to the North American Vertical Datum of 1988 [NAVD 88]) to 25.7 ft (542.6 ft at NAVD 88) at the Charlemont streamgage, and stages for mapped profiles of the downstream reach range from 8.5 ft (165.2 ft at NAVD 88) to 29.0 ft (185.7 ft at NAVD 88) at the West Deerfield streamgage. The simulated water-surface profiles were combined with a geographic information system digital elevation model derived from 0.5-ft vertical accuracy light detection and ranging (lidar) data to create the two sets of flood-inundation maps. The availability of the flood-inundation maps at http://water.usgs.gov/osw/flood_inundation/, combined with information regarding current (near real-time) stage from the two U.S. Geological Survey streamgages in the study reach, can provide emergency management personnel and residents with information to aid in flood response activities, such as evacuations and road closures, and with postflood recovery efforts. The flood-inundation maps are nonregulatory, but provide Federal, State, and local agencies and the public with estimates of the potential extent of flooding during selected peak-flow events.

Massachusetts↗

USGS2022

Elevation-area-capacity relationships of Lake Powell in 2018 and estimated loss of storage capacity since 1963

Lake Powell is the second largest constructed water reservoir by storage capacity in the United States and represents a critical component in management of water resources in the Colorado River Basin. The reservoir provides hydroelectric power generation at Glen Canyon Dam, banks water storage for the Upper Colorado River Basin, stabilizes water commitments downstream, and buffers the Lower Colorado River Basin, including Lake Mead, against sedimentation and fluctuations in hydrological conditions. With completion of the dam in 1963, Lake Powell steadily filled with water before reaching full pool in 1980 and has become a popular destination for recreation, welcoming more than 4 million visitors per year. Since the early 2000s, severe drought and increases in water demand have resulted in a significant drop in reservoir elevation and stored water, prompting a heightened level of interest in the current state and future of Lake Powell. Beginning in 2017, the U.S. Geological Survey, in cooperation with the Bureau of Reclamation, completed topobathymetric surveys of Lake Powell for the first update of elevation-area-capacity relationships since 1986. This report presents results of these surveys and comparisons with estimates from previous surveys. The storage volume and surface area, as of completion of the topobathymetric survey in spring 2018, are calculated at 0.33-foot (0.10-meter) increments for elevations ranging from 3,120.08 to 3,717.19 feet above the North American Vertical Datum of 1988 (NAVD 88). Between 0.33-foot increments, the storage volumes and areas were linearly interpolated at 0.01-foot intervals. Interpolation error in the 0.01-foot interval estimates was assessed at lower (3,160.00–3,161.00 feet above NAVD 88), middle (3,400.00–3,401.00 feet above NAVD 88), and upper (3,700.00–3,711.00 feet above NAVD 88) elevations. The interpolated storage capacity and area estimates are comparable to the measured values with differences ranging from 0.00 to 0.02 percent and from −0.01 to 0.03 percent, respectively. Current storage capacity at full pool (3702.91 feet above NAVD 88) is 25,160,000 acre-feet. Compared to previously published estimates, this volume represents a 6.79 percent or 1,833,000-acre-foot decrease in storage capacity from 1963 to 2018 and a 4.00 percent or 1,049,000-acre-foot decrease from 1986 to 2018. Areal extent, as of spring 2018, at full pool is 159,200 acres, which represents a 1.33-percent decrease from 1963 to 2018 and a 0.96 percent decrease from 1986 to 2018.

Arizona, Utah↗

USGS2017

Interpreting surveys to estimate the size of the monarch butterfly population: Pitfalls and prospects

To assess the change in the size of the eastern North American monarch butterfly summer population, studies have used long-term data sets of counts of adult butterflies or eggs per milkweed stem. Despite the observed decline in the monarch population as measured at overwintering sites in Mexico, these studies found no decline in summer counts in the Midwest, the core of the summer breeding range, leading to a suggestion that the cause of the monarch population decline is not the loss of Midwest agricultural milkweeds but increased mortality during the fall migration. Using these counts to estimate population size, however, does not account for the shift of monarch activity from agricultural fields to non-agricultural sites over the past 20 years, as a result of the loss of agricultural milkweeds due to the near-ubiquitous use of glyphosate herbicides. We present the counter-hypotheses that the proportion of the monarch population present in non-agricultural habitats, where counts are made, has increased and that counts reflect both population size and the proportion of the population observed. We use data on the historical change in the proportion of milkweeds, and thus monarch activity, in agricultural fields and non-agricultural habitats to show why using counts can produce misleading conclusions about population size. We then separate out the shifting proportion effect from the counts to estimate the population size and show that these corrected summer monarch counts show a decline over time and are correlated with the size of the overwintering population. In addition, we present evidence against the hypothesis of increased mortality during migration. The milkweed limitation hypothesis for monarch decline remains supported and conservation efforts focusing on adding milkweeds to the landscape in the summer breeding region have a sound scientific basis.

PLoS ONE↗

USGS2017

Atmospheric rivers emerge as a global science and applications focus

Recent advances in atmospheric sciences and hydrology have identified the key role of atmo-spheric rivers (ARs) in determining the distribution of strong precipitation events in the midlatitudes. The growth of the subject is evident in the increase in scientific publications that discuss ARs (Fig. 1a). Combined with related phenomena, that is, warm conveyor belts (WCBs) and tropical moisture exports (TMEs), the frequency, position, and strength of ARs determine the occurrence of floods, droughts, and water resources in many parts of the world. A conference at the Scripps Institution of Oceanography in La Jolla, California, recently gathered over 100 experts in atmospheric, hydrologic, oceanic, and polar science; ecology; water management; and civil engineering to assess the state of AR science and to explore the need for new information. This first International Atmospheric Rivers Conference (IARC) allowed for much needed introductions and interactions across fields and regions, for example, participants came from five continents, and studies covered ARs in six continents and Greenland (Fig. 1b). IARC also fostered discussions of the status and future of AR science, and attendees strongly supported the idea of holding another IARC at the Scripps Institution of Oceanography in the summer of 2018.

Bulletin of the American Meteorological Society↗

USGS2012

Bathymetry and capacity of Blackfoot Reservoir, Caribou County, Idaho, 2011

The U.S. Geological Survey (USGS), in cooperation with the Shoshone-Bannock Tribes, surveyed the bathymetry and selected above-water sections of Blackfoot Reservoir, Caribou County, Idaho, in 2011. Reservoir operators manage releases from Government Dam on Blackfoot Reservoir based on a stage-capacity relation developed about the time of dam construction in the early 1900s. Reservoir operation directly affects the amount of water that is available for irrigation of agricultural land on the Fort Hall Indian Reservation and surrounding areas. The USGS surveyed the below-water sections of the reservoir using a multibeam echosounder and real-time kinematic global positioning system (RTK-GPS) equipment at full reservoir pool in June 2011, covering elevations from 6,090 to 6,119 feet (ft) above the North American Vertical Datum of 1988 (NAVD 88). The USGS used data from a light detection and ranging (LiDAR) survey performed in 2000 to map reservoir bathymetry from 6,116 to 6,124 ft NAVD 88, which were mostly in depths too shallow to measure with the multibeam echosounder, and most of the above-water section of the reservoir (above 6,124 ft NAVD 88). Selected points and bank erosional features were surveyed by the USGS using RTK-GPS and a total station at low reservoir pool in September 2011 to supplement and verify the LiDAR data. The stage-capacity relation was revised and presented in a tabular format. The datasets show a 2.0-percent decrease in capacity from the original survey, due to sedimentation or differences in accuracy between surveys. A 1.3-percent error also was detected in the previously used capacity table and measured water-level elevation because of questionable reference elevation at monitoring stations near Government Dam. Reservoir capacity in 2011 at design maximum pool of 6,124 ft above NAVD 88 was 333,500 acre-ft.

Idaho↗

USGS2015

Geology of Joshua Tree National Park geodatabase

The database in this Open-File Report describes the geology of Joshua Tree National Park and was completed in support of the National Cooperative Geologic Mapping Program of the U.S. Geological Survey (USGS) and in cooperation with the National Park Service (NPS). The geologic observations and interpretations represented in the database are relevant to both the ongoing scientific interests of the USGS in southern California and the management requirements of NPS, specifically of Joshua Tree National Park (JOTR). Joshua Tree National Park is situated within the eastern part of California’s Transverse Ranges province and straddles the transition between the Mojave and Sonoran deserts. The geologically diverse terrain that underlies JOTR reveals a rich and varied geologic evolution, one that spans nearly two billion years of Earth history. The Park’s landscape is the current expression of this evolution, its varied landforms reflecting the differing origins of underlying rock types and their differing responses to subsequent geologic events. Crystalline basement in the Park consists of Proterozoic plutonic and metamorphic rocks intruded by a composite Mesozoic batholith of Triassic through Late Cretaceous plutons arrayed in northwest-trending lithodemic belts. The basement was exhumed during the Cenozoic and underwent differential deep weathering beneath a low-relief erosion surface, with the deepest weathering profiles forming on quartz-rich, biotite-bearing granitoid rocks. Disruption of the basement terrain by faults of the San Andreas system began ca. 20 Ma and the JOTR sinistral domain, preceded by basalt eruptions, began perhaps as early as ca. 7 Ma, but no later than 5 Ma. Uplift of the mountain blocks during this interval led to erosional stripping of the thick zones of weathered quartz-rich granitoid rocks to form etchplains dotted by bouldery tors—the iconic landscape of the Park. The stripped debris filled basins along the fault zones. Mountain ranges and basins in the Park exhibit an east-west physiographic grain controlled by left-lateral fault zones that form a sinistral domain within the broad zone of dextral shear along the transform boundary between the North American and Pacific plates. Geologic and geophysical evidence reveal that movement on the sinistral faults zones has resulted in left steps along the zones, resulting in the development of sub-basins beneath Pinto Basin and Shavers and Chuckwalla Valleys. The sinistral fault zones connect the Mojave Desert dextral faults of the Eastern California Shear Zone to the north and east with the Coachella Valley strands of the southern San Andreas Fault Zone to the west. Quaternary surficial deposits accumulated in alluvial washes and playas and lakes along the valley floors; in alluvial fans, washes, and sheet wash aprons along piedmonts flanking the mountain ranges; and in eolian dunes and sand sheets that span the transition from valley floor to piedmont slope. Sequences of Quaternary pediments are planed into piedmonts flanking valley-floor and upland basins, each pediment in turn overlain by successively younger residual and alluvial surficial deposits.

California↗

USGS2023

Flood-inundation maps for Fourmile Creek at Silver Grove, Kentucky

Digital flood-inundation maps for a 3.4-mile reach of Fourmile Creek at Silver Grove, Kentucky, were created by the U.S. Geological Survey (USGS) in cooperation with the City of Silver Grove and the U.S. Army Corps of Engineers Louisville District. Because the City of Silver Grove is subject to flooding from Fourmile Creek and the Ohio River (backwater flooding up Fourmile Creek), a set of flood-inundation maps was created, including maps for each flooding source considered independently and for possible scenarios involving flooding from both sources combined. The flood-inundation maps depict estimates of the areal extent and depth of flooding corresponding to a range of gage heights (gage height is commonly referred to as “stage,” or the water-surface elevation at a streamgage) at the USGS streamgage on Fourmile Creek at Grays Crossing at Silver Grove, Ky. (station number 03238785), and the USGS streamgage on Fourmile Creek at Highway 8 at Silver Grove, Ky. (station number 03238798). Near-real-time stages at these streamgages can be obtained from the USGS National Water Information System at https://waterdata.usgs.gov/ . The USGS streamgage on the Ohio River at Cincinnati, Ohio (station number 03255000), is also important in this study because the National Weather Service (NWS) Advanced Hydrologic Prediction Service (AHPS; https://water.weather.gov/ahps/ ) forecasts flood hydrographs for this site (NWS AHPS site CCNO1). The peak-stage information forecast by the NWS AHPS can be used in conjunction with the maps developed in this study to show predicted areas of flood inundation. Flood profiles were computed for the Fourmile Creek study reach by means of a one-dimensional, step-backwater hydraulic model (HEC-RAS) developed by the U.S. Army Corps of Engineers. The hydraulic model was calibrated by using the current stage-discharge relation (USGS rating number 1.1) at USGS streamgage 03238785, Fourmile Creek at Grays Crossing at Silver Grove, Ky. The model was then used to compute water-surface profiles for 83 combinations of flood stages on the Ohio River and Fourmile Creek ranging from approximately base flow to greater than a 2-percent annual exceedance probability flood in the model reach. An additional 50 water-surface profiles were computed for backwater-only flooding (from the Ohio River) for flood elevations (referenced to the North American Vertical Datum of 1988 [NAVD 88]) at 1-foot intervals referenced to USGS streamgage 03238798, Fourmile Creek at Highway 8 at Silver Grove, Ky.; these elevations ranged from approximately normal pool (460 ft, NAVD 88) to approximately a 0.2-percent annual exceedance probability flood (509 ft, NAVD 88) on the Ohio River. The computed water-surface profile information was then combined with a digital elevation model derived from light detection and ranging (lidar) data to delineate the approximate flooded areas. The digital flood-inundation maps are available through the USGS Flood Inundation Mapper application ( https://fim.wim.usgs.gov/fim/ ), which presents map libraries and provides detailed information on flood extent and depths for selected sites. The flood-inundation maps developed in this study, in conjunction with the real-time stage data from the USGS streamgages on Fourmile Creek at Silver Grove, Ky., and forecasted stream stages from the NWS AHPS, are intended to provide information that can help inform the public about potential flooding and provide emergency management personnel with a tool to efficiently manage emergency flood operations, such as evacuations and road closures, and assist in postflood recovery efforts.

Kentucky↗

USGS2005

Volcano surveillance by ACR silver fox

Recent growth in the business of unmanned air vehicles (UAVs) both in the US and abroad has improved their overall capability, resulting in a reduction in cost, greater reliability and adoption into areas where they had previously not been considered. Uses in coastal and border patrol, forestry and agriculture have recently been evaluated in an effort to expand the observed area and reduce surveillance and reconnaissance costs for information gathering. The scientific community has both contributed and benefited greatly in this development. A larger suite of light-weight miniaturized sensors now exists for a range of applications which in turn has led to an increase in the gathering of information from these autonomous vehicles. In October 2004 the first eruption of Mount St Helens since 1986 caused tremendous interest amoUg people worldwide. Volcanologists at the U.S. Geological Survey rapidly ramped up the level of monitoring using a variety of ground-based sensors deployed in the crater and on the flanks of the volcano using manned helicopters. In order to develop additional unmanned sensing methods that can be used in potentially hazardous and low visibility conditions, a UAV experiment was conducted during the ongoing eruption early in November. The Silver Fox UAV was flown over and inside the crater to perform routine observation and data gathering, thereby demonstrating a technology that could reduce physical risk to scientists and other field operatives. It was demonstrated that UAVs can be flown autonomously at an active volcano and can deliver real time data to a remote location. Although still relatively limited in extent, these initial flights provided information on volcanic activity and thermal conditions within the crater and at the new (2004) lava dome. The flights demonstrated that readily available visual and infrared video sensors mounted in a small and relatively low-cost aerial platform can provide useful data on volcanic phenomena. This was made possible by utilizing GPS and computer-controlled flight direction and stabilization to acquire and track target areas within the Mount St. Helens crater. It was also determined that additional light-weight sensor development will be needed to enable autonomous measurements of volcanic gasses and imaging in poor-weather conditions. Copyright ?? 2005 by the American Institute of Aeronautics and Astronautics, Inc. All rights reserved.

Conference Paper↗

USGS2007

Geologic Map of the Big Delta B-1 Quadrangle, East-Central Alaska

Geologic mapping and U-Pb age dating of rocks from the Big Delta B-1 quadrangle, east-central Alaska, have yielded new insights into the geology and gold mineral resource for the headwater region of the Goodpaster River, northeast of Delta, Alaska. The area lies within the Yukon-Tanana Upland and is underlain by Paleozoic and Cretaceous crystalline bedrock and contains several gold mines and prospects. The Paleozoic units include biotite gneiss, quartzite interlayered with metapelite, and amphibolite gneiss. The Paleozoic units were intruded during the Devonian by tonalitic to granitic plutons, which, as a result of regional Mesozoic metamorphism and tectonism, are now augen gneiss and biotite orthogneiss. The Mesozoic regional metamorphism and ductile deformation of the entire Yukon-Tanana Upland culminated by the Late Cretaceous (about 116 Ma) as a result of northwest-directed regional transpression along the southern margin of the North American craton. This dynamothermal episode was followed by invasion of syn- to post-tectonic granodioritic to granitic batholiths during the Late Cretaceous (about 113-107 Ma), followed by a pulse of 100-95 Ma quartz feldspar porphyry intrusions. Gold mineralization is spatially associated with various post-tectonic Late Cretaceous granitic dikes and batholiths throughout the quadrangle. A northeast-trending structural corridor, described herein as the Black Mountain tectonic zone, both controlled the emplacement of some of the Cretaceous intrusive rocks, gold deposits, and prospects, as well as formed a deep-seated crustal conduit along which a subsequent rhyolite flow-dome complex erupted during the Paleocene. Tertiary uplift and erosion resulted in the development of extensive erosional pediments. Quaternary alpine glaciation carved beautiful, broad valleys in the eastern part of the quadrangle, leaving behind terminal moraines in the headwater region of the Goodpaster river drainage. Continued Holocene to Recent deformation along the Black Mountain tectonic zone has offset Tertiary terraces, as well as Quaternary fluvial and alluvial deposits, indicating that the area has a long, complex, and ongoing tectonic history.

Scientific Investigations Map↗

USGS2008

Variations in Community Exposure and Sensitivity to Tsunami Hazards on the Open-Ocean and Strait of Juan de Fuca Coasts of Washington

Evidence of past events and modeling of potential future events suggest that tsunamis are significant threats to communities on the open-ocean and Strait of Juan de Fuca coasts of Washington. Although potential tsunami-inundation zones from a Cascadia Subduction Zone (CSZ) earthquake have been delineated, the amount and type of human development in tsunami-prone areas have not been documented. A vulnerability assessment using geographic-information-system tools was conducted to document variations in developed land, human populations, economic assets, and critical facilities relative to CSZ-related tsunami-inundation zones among communities on the open-ocean and Strait of Juan de Fuca coasts of Washington (including Clallam, Jefferson, Grays Harbor, and Pacific Counties). The tsunami-inundation zone in these counties contains 42,972 residents (24 percent of the total study-area population), 24,934 employees (33 percent of the total labor force), and 17,029 daily visitors to coastal Washington State Parks. The tsunami-inundation zone also contains 2,908 businesses that generate $4.6 billion in annual sales volume (31 and 40 percent of study-area totals, respectively) and tax parcels with a combined total value of $4.5 billion (25 percent of the study-area total). Although occupancy values are not known for each site, the tsunami-inundation zone also contains numerous dependent-population facilities (for example, schools and child-day-care centers), public venues (for example, religious organizations), and critical facilities (for example, police stations and public-work facilities). Racial diversity of residents in tsunami-prone areas is low?89 percent of residents are White and 8 percent are American Indian or Alaska Native. Nineteen percent of the residents in the tsunami-inundation zone are over 65 years in age, 30 percent of the residents live on unincorporated county lands, and 35 percent of the households are renter occupied. Employees in the tsunami-inundation zone are largely in businesses related to health care and social assistance, accommodation and food services, and retail trade, reflecting businesses that cater to a growing retiree and tourist population. Community vulnerability, described here by exposure (the amount of assets in tsunami-prone areas) and sensitivity (the relative percentage of assets in tsunami-prone areas) varies among 13 incorporated cities, 7 Indian reservations, and 4 counties. The City of Aberdeen has the highest relative community exposure to tsunamis, whereas the City of Long Beach has the highest relative community sensitivity. Levels of community exposure and sensitivity to tsunamis are found to be related to the amount and percentage, respectively, of a community?s land that is in a tsunami-inundation zone. This report will further the dialogue on societal risk to tsunami hazards in Washington and help risk managers to determine where additional risk-reduction strategies may be needed.

Scientific Investigations Report↗

USGS2020

Breeding birds of the upper Mississippi River floodplain forest: One community in a changing forest, 1994 to 1997

Floodplain forest on the upper Mississippi River (UMR), a unique habitat in the Midwest that is important for many bird species, has been reduced and is undergoing continued reduction and changes in structure and species diversity because of river engineering and invasive species. Hydrological changes are causing tree diversity to decline favoring Acer saccharinum (silver maple) and Fraxinus pennsylvanica (green ash). Invasive Phalaris arundinacea (reed canary grass, Phalaris ) threatens tree regeneration, and recent Agrilus planipennis (emerald ash borer) arrival threatens to decimate the important ash component of the forest canopy. During the 1990s, virtually no information was available about breeding songbird species and abundances on the UMR floodplain forest from along many river miles and a broad range of forest situations (for example, mainland, island, edge, interior). From 1994 to 1997, we surveyed breeding birds and sampled vegetation at 391 random points on UMR floodplain forest along a latitudinal gradient from Red Wing, Minnesota, to Clinton, Iowa, to characterize bird assemblages and associations with gradients in forest structure at survey points (local scale) and land cover composition within a 200-meter radius of survey points (landscape scale). Eighty-six bird species were detected during the study, but 28 species comprised 90 percent of all detections. Species that are typically associated with woodland edge or are tolerant of fragmentation were the most common: Setophaga ruticilla (American Redstart), Troglodytes aedon (House Wren), Turdus migratorius (American Robin), Quiscalus quiscula (Common Grackle), and Vireo gilvus (Warbling Vireo). Species typically associated with large forest patches— Setophaga cerulea (Cerulean Warbler), Hylocichla mustelina (Wood Thrush), and Dryocopus pileatus (Pileated Woodpecker)—were rare. Principal components analyses consistently described local habitat gradients related to canopy cover and Phalaris presence and described landscape gradients related to forest area and areas of open land cover types. However, nonmetric multidimensional scaling revealed no pattern in bird assemblages. Canonical correspondence analyses with local habitat variables for each year revealed that bird assemblages were affected by canopy cover, the presence of Phalaris , and the number of tree species. Four bird species were consistently associated with Phalaris presence or negatively with canopy cover, and no species were associated with the number of tree species variable. Although landscape variables were significantly related to the bird assemblage in canonical correspondence analyses, no bird species were consistently related to any landscape variable. These results indicate that there is one assemblage of forest birds on the UMR composed mainly of edge-tolerant species. Species associated with lower canopy cover and Phalaris presence may be favored to increase in abundance as canopy cover opens as trees die and Phalaris becomes more prevalent.

Illinois, Iowa, Minnesota, Wisconsin↗