Industrial garnet
D.W. Olson
2012, Mining Engineering (64) 64-64
Garnet has been used as a gemstone since the Bronze Age. However, garnet's angular fractures, relatively high hardness and specific gravity, chemical inertness, and nontoxicity make it ideal for many industrial applications. It is also free of crystalline silica and can be recycled....
Geomagnetic detection of the sectorial solar magnetic field and the historical peculiarity of minimum 23-24
Jeffrey J. Love, J. Rigler
2012, Geophysical Research Letters (39)
[1] Analysis is made of the geomagnetic-activityaaindex covering solar cycle 11 to the beginning of 24, 1868–2011. Autocorrelation shows 27.0-d recurrent geomagnetic activity that is well-known to be prominent during solar-cycle minima; some minima also exhibit a smaller amount of 13.5-d recurrence. Previous work has shown that the recent solar...
John B. "Jack" Townshend (1927-2012)
Jeffrey J. Love, Carol A. Finn
2012, Eos, Transactions, American Geophysical Union (93) 524-525
Jack Townshend, geophysicist and dedicated public servant, died on 13 August 2012 in Fairbanks, Alaska. He was 85. Jack's career with the federal government, most of it with the national magnetic observatory program, spanned more than six solar cycles of time, and he retired only days before his death. The...
Developing ShakeCast statistical fragility analysis framework for rapid post-earthquake assessment
K.-W. Lin, D.J. Wald
2012, Conference Paper, Proceedings of the 15th World Conference on Earthquake Engineering (15WCEE), Lisbon, Portugal, September 24-28
When an earthquake occurs, the U. S. Geological Survey (USGS) ShakeMap estimates the extent of potentially damaging shaking and provides overall information regarding the affected areas. The USGS ShakeCast system is a freely-available, post-earthquake situational awareness application that automatically retrieves earthquake shaking data from ShakeMap, compares intensity measures against users’...
Comparison of soil thickness in a zero-order basin in the Oregon Coast Range using a soil probe and electrical resistivity tomography
Michael S. Morse, Ning Lu, Jonathan W. Godt, André Revil, Jeffrey A. Coe
2012, Journal of Geotechnical and Geoenvironmental Engineering (138) 1470-1482
Accurate estimation of the soil thickness distribution in steepland drainage basins is essential for understanding ecosystem and subsurface response to infiltration. One important aspect of this characterization is assessing the heavy and antecedent rainfall conditions that lead to shallow landsliding. In this paper, we investigate the direct current (DC) resistivity...
Data quality of seismic records from the Tohoku, Japan earthquake as recorded across the Albuquerque Seismological Laboratory networks
A. T. Ringler, L.S. Gee, B. Marshall, C. R. Hutt, T. Storm
2012, Seismological Research Letters (83) 575-584
Great earthquakes recorded across modern digital seismographic networks, such as the recent Tohoku, Japan, earthquake on 11 March 2011 (Mw = 9.0), provide unique datasets that ultimately lead to a better understanding of the Earth's structure (e.g., Pesicek et al. 2008) and earthquake sources (e.g., Ammon et al. 2011). For...
Conceptual model of sedimentation in the Sacramento-San Joaquin River Delta
David H. Schoellhamer, Scott Wright, Judith Z. Drexler
2012, San Francisco Estuary and Watershed Science (10)
Sedimentation in the Sacramento–San Joaquin River Delta builds the Delta landscape, creates benthic and pelagic habitat, and transports sediment-associated contaminants. Here we present a conceptual model of sedimentation that includes submodels for river supply from the watershed to the Delta, regional transport within the Delta and seaward exchange, and local...
Annual accumulation over the Greenland ice sheet interpolated from historical and newly compiled observation data
Dayong Shen, Yuling Liu, Shengli Huang
2012, Geografiska Annaler, Series A: Physical Geography (94) 377-393
The estimation of ice/snow accumulation is of great significance in quantifying the mass balance of ice sheets and variation in water resources. Improving the accuracy and reducing uncertainty has been a challenge for the estimation of annual accumulation over the Greenland ice sheet. In this study, we kriged and analyzed...
Changing restoration rules: exotic bivalves interact with residence time and depth to control phytoplankton productivity
Lisa V. Lucas, Janet K. Thompson
2012, Ecosphere (3)
Non-native species are a prevalent ecosystem stressor that can interact with other stressors to confound resource management and restoration. We examine how interactions between physical habitat attributes and a particular category of non-native species (invasive bivalves) influence primary production in aquatic ecosystems. Using mathematical models, we show how intuitive relationships...
An evaluation of a mitigation strategy for deer-vehicle collisions
John A. Bissonette, Silvia Rosa
2012, Wildlife Biology (18) 414-423
High mule deer Odocoileus hemionus mortality in southwestern Utah led to the establishment of a mitigation strategy with two major objectives: 1) reduction of wildlife-vehicle collisions and 2) restoration of landscape connectivity to facilitate wildlife movement across the roaded landscape. During our study, we assessed the effectiveness of the mitigation...
Foraging optimally for home ranges
Michael S. Mitchell, Roger A. Powell
2012, Journal of Mammalogy (93) 917-928
Economic models predict behavior of animals based on the presumption that natural selection has shaped behaviors important to an animal's fitness to maximize benefits over costs. Economic analyses have shown that territories of animals are structured by trade-offs between benefits gained from resources and costs of defending them. Intuitively, home...
Evaluation of carbon fluxes and trends (2000-2008) in the Greater Platte River Basin: a sustainability study on the potential biofuel feedstock development
Yingxin Gu, Bruce K. Wylie, Li Zhang, Tagir G. Gilmanov
2012, Biomass and Bioenergy (47) 145-152
This study evaluates the carbon fluxes and trends and examines the environmental sustainability (e.g., carbon budget, source or sink) of the potential biofuel feedstock sites identified in the Greater Platte River Basin (GPRB). A 9-year (2000–2008) time series of net ecosystem production (NEP), a measure of net carbon absorption or...
Directional connectivity in hydrology and ecology
Laurel G. Larsen, Jungyill Choi, Martha K. Nungesser, Judson W. Harvey
2012, Ecological Applications (22) 2204-2220
Quantifying hydrologic and ecological connectivity has contributed to understanding transport and dispersal processes and assessing ecosystem degradation or restoration potential. However, there has been little synthesis across disciplines. The growing field of ecohydrology and recent recognition that loss of hydrologic connectivity is leading to a global decline in biodiversity underscore...
Heat flow in vapor dominated areas of the Yellowstone Plateau volcanic field: implications for the thermal budget of the Yellowstone Caldera
Shaul Hurwitz, Robert Harris, Cynthia Anne Werner, Fred Murphy
2012, Journal of Geophysical Research B: Solid Earth (117)
Characterizing the vigor of magmatic activity in Yellowstone requires knowledge of the mechanisms and rates of heat transport between magma and the ground surface. We present results from a heat flow study in two vapor dominated, acid-sulfate thermal areas in the Yellowstone Caldera, the 0.11 km2 Obsidian Pool Thermal Area...
Fire clay
R.L. Virta
2012, Mining Engineering (64) 50-51
Five companies mined fire clay in four states in 2011. Production, based on a preliminary survey of the fire clay industry, was estimated to be 240 kt (265,000 st), valued at $7.68 million, an increase from 216 kt (238,000 st), valued at $6.12 million in 2010. Missouri was the leading...
Industrial sand and gravel
T.P. Dolley
2012, Mining Engineering (64) 65-65
Domestic production of industrial sand and gravel in 2011 was about 30 Mt (33 million st), increasing slightly compared with 2010. Some important end uses for industrial sand and gravel include abrasives, filtration, foundry, glassmaking, hydraulic fracturing sand (frac sand) and silicon metal applications....
A half-million-year record of paleoclimate from the Lake Manix Core, Mojave Desert, California
Marith C. Reheis, Jordon Bright, Steve P. Lund, David M. Miller, Gary Skipp, Robert J. Fleck
2012, Palaeogeography, Palaeoclimatology, Palaeoecology (365-366) 11-37
Pluvial lakes in the southwestern U.S. responded sensitively to past climate through effects on rainfall, runoff, and evaporation. Although most studies agree that pluvial lakes in the southwestern U.S. reached their highest levels coeval with glacial stages, the specific timing of increased effective moisture and lake-level rise is debated, particularly...
Mineral resource of the month: rhenium
Desiree E. Polyak
2012, Earth (57) 25-25
Rhenium, a silvery-white, heat resistant metal, has increased significantly in importance since its discovery in 1925. First isolated by a team of German chemists studying platinum ore, the mineral was named for the Rhine River. From 1925 until the 1960s, only two metric tons of rhenium were produced worldwide. Since...
From Caprio's lilacs to the USA National Phenology Network
Mark D. Schwartz, Julio L. Betancourt, Jake F. Weltzin
2012, Frontiers in Ecology and the Environment (10) 324-327
Continental-scale monitoring is vital for understanding and adapting to temporal changes in seasonal climate and associated phenological responses. The success of monitoring programs will depend on recruiting, retaining, and managing members of the public to routinely collect phenological observations according to standardized protocols. Here, we trace the development of infrastructure...
Ecological effects of climate change on salt marsh wildlife: a case study from a highly urbanized estuary
Karen M. Thorne, John Y. Takekawa, Deborah L. Elliott-Fisk
2012, Journal of Coastal Research (28) 1477-1487
Coastal areas are high-risk zones subject to the impacts of global climate change, with significant increases in the frequencies of extreme weather and storm events, and sea-level rise forecast by 2100. These physical processes are expected to alter estuaries, resulting in loss of intertidal wetlands and their component wildlife species....
INTERMAGNET and magnetic observatories
Jeffrey J. Love, Arnaud Chulliat
2012, EPOS Newsletter (12) 2-2
A magnetic observatory is a specially designed ground-based facility that supports time-series measurement of the Earth’s magnetic field. Observatory data record a superposition of time-dependent signals related to a fantastic diversity of physical processes in the Earth’s core, mantle, lithosphere, ocean, ionosphere, magnetosphere, and, even, the Sun and solar wind....
Low genetic diversity and minimal population substructure in the endangered Florida manatee: implications for conservation
Kimberly Pause Tucker, Margaret E. Hunter, Robert K. Bonde, James D. Austin, Ann Marie Clark, Cathy A. Beck, Peter M. McGuire, Madan K. Oli
2012, Journal of Mammalogy (93) 1504-1511
Species of management concern that have been affected by human activities typically are characterized by low genetic diversity, which can adversely affect their ability to adapt to environmental changes. We used 18 microsatellite markers to genotype 362 Florida manatees (Trichechus manatus latirostris), and investigated genetic diversity, population structure, and estimated...
Food security in a changing climate
Roger Pulwarty, Gary Eilerts, James Verdin
2012, Solutions Journal (3) 31-34
By 2080 the effects of climate change—on heat waves, floods, sea level rise, and drought—could push an additional 600 million people into malnutrition and increase the number of people facing water scarcity by 1.8 billion. The precise impacts will, however, strongly depend on socioeconomic conditions such as local markets and...
Evidence of late-summer mating readiness and early sexual maturation in migratory tree-roosting bats found dead at wind turbines
P.M. Cryan, J.W. Jameson, E.F. Baerwald, C.K.R. Willis, R.M.R. Barclay, E.A. Snider, E.G. Crichton
2012, PLoS ONE (7)
Understanding animal mating systems is an important component of their conservation, yet the precise mating times for many species of bats are unknown. The aim of this study was to better understand the details and timing of reproductive events in species of bats that die most frequently at wind turbines...
Habitat use by fishes of Lake Superior. II. Consequences of diel habitat use for habitat linkages and habitat coupling in nearshore and offshore waters
Owen T. Gorman, Daniel L. Yule, Jason D. Stockwell
2012, Aquatic Ecosystem Health & Management (15) 355-368
Diel migration patterns of fishes in nearshore (15–80 m depth) and offshore (>80 m) waters of Lake Superior were examined to assess the potential for diel migration to link benthic and pelagic, and nearshore and offshore habitats. In our companion article, we described three types of diel migration: diel vertical migration (DVM),...
