Peat
L.E. Apodaca
2012, Mining Engineering (64) 79-80
In 2011, domestic production of peat, excluding Alaska, was estimated to be 605 kt (667,000 st), compared with 628 kt (629,000 st) in 2010. In 2011, imports increased to 1.1. Mt (1.2 million st) compared with 947 kt (1 million st) in 2010, and exports were estimated to have decreased...
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...
Fold-to-fault progression of a major thrust zone revealed in horses of the North Mountain fault zone, Virginia and West Virginia, USA
Randall C. Orndorff
2012, Journal of Geological Research (2012)
The method of emplacement and sequential deformation of major thrust zones may be deciphered by detailed geologic mapping of these important structures. Thrust fault zones may have added complexity when horse blocks are contained within them. However, these horses can be an important indicator of the fault development holding information...
Mineral resource of the month: tungsten
Kim B. Shedd
2012, Earth (57) 57-57
The article offers information on tungsten. It says that tungsten is a metal found in chemical compounds such as in the scheelite and ore minerals wolframite. It states that tungsten has the highest melting point and it forms a compound as hard as diamond when combined with carbon. It states...
Nitrogen
L.E. Apodaca
2012, Mining Engineering (64) 78-79
Ammonia was produced by 12 companies at 27 plants in 15 states in the United States during 2011. Sixty-one percent of total U.S. ammonia production capacity was centered in Louisiana, Oklahoma and Texas because of those states' large reserves of natural gas, the dominant domestic feedstock. In 2011, U.S. producers...
Diatomite
R.D. Crangle Jr.
2012, Mining Engineering (64) 48-49
The United States continues to be the world's leading producer and consumer of diatomite. Production of diatomite in the United States during 2011 was estimated to be 600 kt (661,000 st), a slight increase compared with 2010 production. The unit value of diatomite varied widely by end use in 2011....
Drainage network structure and hydrologic behavior of three lake-rich watersheds on the Arctic Coastal Plain, Alaska
C.D. Arp, M.S. Whitman, Benjamin M. Jones, R. Kemnitz, G. Grosse, F.E. Urban
2012, Arctic, Antarctic, and Alpine Research (44) 385-394
Watersheds draining the Arctic Coastal Plain (ACP) of Alaska are dominated by permafrost and snowmelt runoff that create abundant surface storage in the form of lakes, wetlands, and beaded streams. These surface water elements compose complex drainage networks that affect aquatic ecosystem connectivity and hydrologic behavior. The 4676 km2 Fish...
Nuclear and mitochondrial markers reveal evidence for genetically segregated cryptic speciation in giant Pacific octopuses from Prince William Sound, Alaska
Rebecca K. Toussaint, David Scheel, G. Kevin Sage, Sandra L. Talbot
2012, Conservation Genetics (13) 1483-1497
Multiple species of large octopus are known from the north Pacific waters around Japan, however only one large species is known in the Gulf of Alaska (the giant Pacific octopus, Enteroctopus dofleini). Current taxonomy of E. dofleini is based on geographic and morphological characteristics, although with advances in genetic technology...
A national geographic framework for guiding conservation on a landscape scale
Michael J. Millard, Craig A. Czarnecki, John M. Morton, Laura A. Brandt, Jennifer S. Briggs, Frank S. Shipley, Roger G. Sayre, Pamela J. Sponholtz, David Perkins, Darin G. Simpkins, Janith Taylor
2012, Journal of Fish and Wildlife Management (3) 175-183
The U.S. Fish and Wildlife Service, along with the global conservation community, has recognized that the conservation challenges of the 21st century far exceed the responsibilities and footprint of any individual agency or program. The ecological effects of climate change and other anthropogenic stressors do not recognize geopolitical boundaries and,...
A Gibbs sampler for Bayesian analysis of site-occupancy data
Robert M. Dorazio, Daniel Taylor Rodriguez
2012, Methods in Ecology and Evolution (3) 1093-1098
1. A Bayesian analysis of site-occupancy data containing covariates of species occurrence and species detection probabilities is usually completed using Markov chain Monte Carlo methods in conjunction with software programs that can implement those methods for any statistical model, not just site-occupancy models. Although these software programs are quite flexible, considerable...
Assessing the validity of station location assumptions made in the calculation of the geomagnetic disturbance index, Dst
Jennifer Gannon
2012, Space Weather (10)
In this paper, the effects of the assumptions made in the calculation of the Dst index with regard to longitude sampling, hemisphere bias, and latitude correction are explored. The insights gained from this study will allow operational users to better understand the local implications of the Dst index and will...
Lichens: Unexpected anti-prion agents?
Cynthia M. Rodriguez, James P. Bennett, Christopher J. Johnson
2012, Prion (6) 11-16
The prion diseases sheep scrapie and cervid chronic wasting disease are transmitted, in part, via an environmental reservoir of infectivity; prions released from infected animals persist in the environment and can cause disease years later. Central to controlling disease transmission is the identification of methods capable of inactivating these agents...
Introduced and invasive species in novel rangeland ecosystems: friends or foes?
Jayne Belnap, John A. Ludwig, Bradford P. Wilcox, Julio L. Betancourt, W. Richard J. Dean, Benjamin D. Hoffmann, Sue J. Milton
2012, Rangeland Ecology and Management (65) 569-578
Globally, new combinations of introduced and native plant and animal species have changed rangelands into novel ecosystems. Whereas many rangeland stakeholders (people who use or have an interest in rangelands) view intentional species introductions to improve forage and control erosion as beneficial, others focus on unintended costs, such as increased...
A terrestrial lidar-based workflow for determining three-dimensional slip vectors and associated uncertainties
Peter O. Gold, Eric Cowgill, Oliver Kreylos, Ryan D. Gold
2012, Geosphere (8) 431-442
Three-dimensional (3D) slip vectors recorded by displaced landforms are difficult to constrain across complex fault zones, and the uncertainties associated with such measurements become increasingly challenging to assess as landforms degrade over time. We approach this problem from a remote sensing perspective by using terrestrial laser scanning (TLS) and 3D...
Geologic isolation of nuclear waste at high latitudes: the role of ice sheets
M. Person, J. McIntosh, N. Iverson, C. E. Neuzil, V. Bense
2012, Geofluids (12) 1-6
Geologic isolation of high-level nuclear waste from the biosphere requires special consideration in countries at high latitudes (>40°N) owing to the possibility of future episodes of continental glaciation (Talbot 1999). It is now widely recognized that Pleistocene continental glaciations have had a profound effect on rates of sediment erosion (Cuffey...
P-T-t conditions, Nd and Pb isotopic compositions and detrital zircon geochronology of the Massabesic Gneiss Complex, New Hampshire: isotopic and metamorphic evidence for the identification of Gander basement, central New England
Michael J. Dorais, Robert P. Wintsch, Michael J. Kunk, John Aleinikoff, William Burton, Christine Underdown, Charles M. Kerwin
2012, American Journal of Science (312) 1049-1097
We present new evidence for the assignment of the Neoproterozoic Massabesic Gneiss Complex of New Hampshire to the Gander terrane rather than the Avalon terrane. The majority of Avalonian (sensu stricto) igneous and meta-igneous rocks as defined in Maritime Canada have positive whole-rock ɛNd compared to more negative values for...
2014 Update of the United States National Seismic Hazard Maps
M.D. Petersen, C.S. Mueller, K. M. Haller, M. Moschetti, S. C. Harmsen, E. H. Field, K.S. Rukstales, Y. Zeng, D. M. Perkins, P. Powers, S. Rezaeian, N. Luco, A. Olsen, R. Williams
2012, Conference Paper, Proceedings of the 15th World Conference on Earthquake Engineering (15WCEE), Lisbon, Portugal, September 24-28
The U.S. National Seismic Hazard Maps are revised every six years, corresponding with the update cycle of the International Building Code. These maps cover the conterminous U.S. and will be updated in 2014 using the best-available science that is obtained from colleagues at regional and topical workshops, which are convened...
Arctic shorebirds in North America: A decade of monitoring
Jonathan R. Bart, Victoria H. Johnston, editor(s)
2012, Studies in Avian Biology 44
Each year shorebirds from North and South America migrate thousands of miles to spend the summer in the Arctic. There they feed in shoreline marshes and estuaries along some of the most productive and pristine coasts anywhere. With so much available food they are able to reproduce almost explosively; and...
Effects of low-density feeding on elk–fetus contact rates on Wyoming feedgrounds
Tyler G. Creech, Paul C. Cross, Brandon M. Scurlock, Eric Maichak, Jared D. Rogerson, John C. Henningsen, Scott Creel
2012, Journal of Wildlife Management (76) 877-886
High seroprevalance for Brucella abortus among elk on Wyoming feedgrounds suggests that supplemental feeding may influence parasite transmission and disease dynamics by altering the rate at which elk contact infectious materials in their environment. We used proximity loggers and video cameras to estimate rates of elk-to-fetus contact (the primary source...
Borates
R.D. Crangle Jr.
2012, Mining Engineering (64) 39-40
Four minerals represent 90 percent of the borates used by industry worldwide — the sodium borates, tincal and kernite; the calcium borate, colemanite; and the sodium-calcium borate, ulexite....
A graphical method to evaluate predominant geochemical processes occurring in groundwater systems for radiocarbon dating
Liang-Feng Han, Niel Plummer, Pradeep Aggarwal
2012, Chemical Geology (318-319) 88-112
A graphical method is described for identifying geochemical reactions needed in the interpretation of radiocarbon age in groundwater systems. Graphs are constructed by plotting the measured 14C, δ13C, and concentration of dissolved inorganic carbon and are interpreted according to specific criteria to recognize water samples that are consistent with a...
Early indications of soil recovery from acidic deposition in U.S. red spruce forests
Gregory B. Lawrence, Walter C. Shortle, Mark B. David, Kevin T. Smith, Richard A.F. Warby, Andrei G. Lapenis
2012, Soil Science Society of America Journal (76) 1407-1417
Forty to fifty percent decreases in acidic deposition through the 1980s and 1990s led to partial recovery of acidified surface waters in the northeastern United States; however, the limited number of studies that have assessed soil change found increased soil acidification during this period. From existing data, it's not clear...
Discussion of “Deglacial paleoclimate in the southwestern United States: an abrupt 18.6 cold event and evidence for a North Atlantic forcing of Termination I” by M.S. Lachniet, Y. Asmerom and V. Polyak
Isaac J. Winograd
2012, Quaternary Science Reviews (45) 126-128
Utilizing a stable isotopic time series obtained from a speleothem (PC-1), which grew between 20.1 and 15.6 ka, Lachniet, Asmeron and Polyak (2011; hereafter LAP) present evidence for a significant cold event in the southern Great Basin at 18.6 ka, a finding that we accept. Supplementing this short record with...
Habitat use by fishes of Lake Superior. I. Diel patterns of habitat use in nearshore and offshore waters of the Apostle Islands region
O. T. Gorman, D.L. Yule, J.D. Stockwell
2012, Aquatic Ecosystem Health & Management (15) 333-354
Diel patterns of distribution of fishes in nearshore (15–80 m depth) and offshore (>80 m) waters of the Apostle Islands region of Lake Superior were described using bottom trawls, mid-water trawls, and acoustic gear during day and night sampling. These data revealed three types of diel migration: diel vertical migration (DVM), diel...
Late Holocene earthquake history of the Brigham City segment of the Wasatch fault zone at the Hansen Canyon, Kotter Canyon, and Pearsons Canyon trench sites, Box Elder County, Utah
Christopher B. DuRoss, Stephen F. Personius, Anthony J. Crone, Greg N. McDonald, Richard W. Briggs
2012, Special Study 142
Of the five central segments of the Wasatch fault zone (WFZ) having evidence of recurrent Holocene surface-faulting earthquakes, the Brigham City segment (BCS) has the longest elapsed time since its most recent surface-faulting event (~2.1 kyr) compared to its mean recurrence time between events (~1.3 kyr). Thus, the BCS has...
