Pumice and pumicite
R.D. Crangle Jr.
2012, Mining Engineering (64) 85-86
Production of pumice in the United States during 2011 was estimated to be 380 kt (420,000 st), a 3-percent decrease compared with 2010. The unit value of pumice varied by end use in 2011. Pumice used as an abrasive was priced at $10.39/t ($9.30/st), while specialty-grade pumice, used in cosmetics,...
Lithium
B.W. Jaskula
2012, Mining Engineering (64) 72-73
In 2011, world lithium consumption was estimated to have been about 25 kt (25,000 st) of lithium contained in minerals and compounds, a 10-percent increase from 2010. U.S. consumption was estimated to have been about 2 kt (2,200 st) of contained lithium, a 100-percent increase from 2010. The United States...
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....
Allowable levels of take for the trade in Nearctic songbirds
Fred A. Johnson, Matthew A.H. Walters, G. Scott Boomer
2012, Ecological Applications (22) 1114-1130
The take of Nearctic songbirds for the caged-bird trade is an important cultural and economic activity in Mexico, but its sustainability has been questioned. We relied on the theta-logistic population model to explore options for setting allowable levels of take for 11 species of passerines that were subject to legal...
Evidence of autumn spawning in Suwannee River Gulf sturgeon, Acipenser oxyrinchus desotoi (Vladykov, 1955)
M.T. Randall, K. J. Sulak
2012, Journal of Applied Ichthyology (28) 489-495
Evidence of autumn spawning of Gulf sturgeon Acipenser oxyrinchus desotoi in the Suwannee River, Florida, was compiled from multiple investigations between 1986 and 2008. Gulf sturgeon are known from egg collections to spawn in the springtime months following immigration into rivers. Evidence of autumn spawning includes multiple captures of sturgeon...
A horizon scanning assessment of current and potential future threats to migratory shorebirds
William J. Sutherland, José A. Alves, Tatsuya Amano, Charlotte H. Chang, Nicholas C. Davidson, C. Max Finlayson, Jennifer A. Gill, Robert E. Gill Jr., Patricia M. González, Tomas Gretar Gunnarsson, David Kleijn, Chris J. Spray, Tamás Székely, Des B.A. Thompson
2012, Ibis (154) 663-679
We review the conservation issues facing migratory shorebird populations that breed in temperate regions and use wetlands in the non-breeding season. Shorebirds are excellent model organisms for understanding ecological, behavioural and evolutionary processes and are often used as indicators of wetland health. A global team of experienced shorebird researchers identified...
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...
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...
Calving seismicity from iceberg-sea surface interactions
T.C. Bartholomaus, C.F. Larsen, Shad O’Neel, M.E. West
2012, Journal of Geophysical Research F: Earth Surface (117)
Iceberg calving is known to release substantial seismic energy, but little is known about the specific mechanisms that produce calving icequakes. At Yahtse Glacier, a tidewater glacier on the Gulf of Alaska, we draw upon a local network of seismometers and focus on 80 hours of concurrent, direct observation of...
Gypsum
R.D. Crangle Jr.
2012, Mining Engineering (64) 59-59
The United States is the world's fourth leading producer and consumer of gypsum. Production of gypsum in the U.S. during 2011 was estimated to be 9.4 Mt (103 million st), an increase of 6 percent compared with 2010 production. The average price of mined crude gypsum was $7/t ($6.35/st). Synthetic...
Hillslope hydrology and stability
Ning Lu, Jonathan Godt
2012, Book
Landslides are caused by a failure of the mechanical balance within hillslopes. This balance is governed by two coupled physical processes: hydrological or subsurface flow and stress. The stabilizing strength of hillslope materials depends on effective stress, which is diminished by rainfall. This book presents a cutting-edge quantitative approach to...
Geologic processes influence the effects of mining on aquatic ecosystems
Travis S. Schmidt, William H. Clements, Richard B. Wanty, Philip L. Verplanck, Stan E. Church, Carma A. San Juan, David L. Fey, Barnaby W. Rockwell, Ed H. DeWitt, Terry L. Klein
2012, Ecological Applications (22) 870-879
Geologic processes strongly influence water and sediment quality in aquatic ecosystems but rarely are geologic principles incorporated into routine biomonitoring studies. We test if elevated concentrations of metals in water and sediment are restricted to streams downstream of mines or areas that may discharge mine wastes. We surveyed 198 catchments...
Anisotropic path modeling to assess pedestrian-evacuation potential from Cascadia-related tsunamis in the US Pacific Northwest
Nathan J. Wood, Mathew C. Schmidtlein
2012, Natural Hazards (62) 275-300
Recent disasters highlight the threat that tsunamis pose to coastal communities. When developing tsunami-education efforts and vertical-evacuation strategies, emergency managers need to understand how much time it could take for a coastal population to reach higher ground before tsunami waves arrive. To improve efforts to model pedestrian evacuations from tsunamis,...
Geologic setting, sedimentary architecture, and paragenesis of the Mesoproterozoic sediment-hosted Sheep Creek Cu-Co-Ag deposit, Helena embayment, Montana
Garth E. Graham, Murray W. Hitzman, Jerry Zieg
2012, Economic Geology (107) 1115-1141
The northern margin of the Helena Embayment contains extensive syngenetic to diagenetic massive pyrite horizons that extend over 25 km along the Volcano Valley-Buttress fault zone and extend up to 8 km basinward (south) within the Mesoproterozoic Newland Formation. The Sheep Creek Cu-Co deposit occurs within a structural block along...
Resolving hyporheic and groundwater components of streambed water flux
Aditi S. Bhaskar, Judson W. Harvey, Eric J. Henry
2012, Water Resources Research (48)
Hyporheic and groundwater fluxes typically occur together in permeable sediments beneath flowing stream water. However, streambed water fluxes quantified using the thermal method are usually interpreted as representing either groundwater or hyporheic fluxes. Our purpose was to improve understanding of co-occurring groundwater and hyporheic fluxes using streambed temperature measurements and...
Correlation of resource plays and biodiversity patterns: accumulation of organic-rich shale tracks taxonomic turnover
Jennifer D. Eoff
2012, GCAGS Journal (1) 1-12
Similar paleogeographic and paleotectonic settings characterize most self-sourced shale hydrocarbon plays. Their deposition occurred within similar orders of magnitude of eustatic events and during geologic periods characterized by “warm” (or transitional) climates and calcitic seas. In addition, the stratigraphic occurrence of shale plays parallels certain historical patterns of marine metazoan...
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...
Sulfur
L.E. Apodaca
2012, Mining Engineering (64) 91-92
In 2011, elemental sulfur and the byproduct sulfuric acid were produced at 109 operations in 29 states and the U.S. Virgin Islands. Total shipments were valued at about $1.6 billion. Elemental sulfur production was 8.2 Mt (9 million st); Louisiana and Texas accounted for about 53 percent of domestic production....
Current and potential sustainable corn stover feedstock for biofuel production in the United States
Zhengxi Tan, Shu-Guang Liu, Larry L. Tieszen, Norman Bliss
2012, Biomass and Bioenergy (47) 372-386
Increased demand for corn (Zea mays L.) stover as a feedstock for cellulosic ethanol raises concerns about agricultural sustainability. Excessive corn stover harvesting could have long-term impacts on soil quality. We estimated current and future stover production and evaluated the potential harvestable stover amount (HSA) that could be used for biofuel...
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...
Ball clay
R.L. Virta
2012, Mining Engineering (64) 33-34
Four companies — H.C. Spinks Clay Co., Inc., Imerys Group, Old Hickory Clay Co., and Unimin Corp. — mined ball clay in four states in 2011. Production, on the basis of preliminary data, was 940 kt (1.04 million st) with an estimated value of $44.2 million. This is a 3-percent...
Exploration review
D.R. Wilburn, T.D. Rapstine, E.C. Lee
2012, Mining Engineering (64) 40-60
This summary of international mineral exploration activities for the year 2011 draws upon available information from industry sources, published literature and U.S. Geological Survey (USGS) specialists. This summary provides data on exploration budgets by region and mineral commodity, identifies significant mineral discoveries and areas of mineral exploration, discusses government programs...
Sequential development of platform to off-platform facies of the great American carbonate bank in the central Appalachians
David K. Brezinski, John F. Taylor, John E. Repetski
2012, Book chapter, The great American carbonate bank: The geology and economic resources of the Cambrian–Ordovician Sauk megasequence of Laurentia
In the central Appalachians, carbonate deposition of the great American carbonate bank began during the Early Cambrian with the creation of initial ramp facies of the Vintage Formation and lower members of the Tomstown Formation. Vertical stacking of bioturbated subtidal ramp deposits (Bolivar Heights Member) and dolomitized microbial boundtsone (Fort...
Alaska's rare earth deposits and resource potential
James C. Barker, Bradley S. Van Gosen
2012, Mining Engineering (64) 20-32
Alaska’s known mineral endowment includes some of the largest and highest grade deposits of various metals, including gold, copper and zinc. Recently, Alaska has also been active in the worldwide search for sources of rare earth elements (REE) to replace exports now being limitedby China. Driven by limited supply of...
Bioenergetic response by steelhead to variation in diet, thermal habitat, and climate in the north Pacific Ocean
Margaret E. Atcheson, Katherine W. Myers, David A. Beauchamp, Nathan J. Mantua
2012, Transactions of the American Fisheries Society (141) 1081-1096
Energetic responses of steelhead Oncorhynchus mykiss to climate-driven changes in marine conditions are expected to affect the species’ ocean distribution, feeding, growth, and survival. With a unique 18-year data series (1991–2008) for steelhead sampled in the open ocean, we simulated interannual variation in prey consumption and growth efficiency of steelhead...
