P is for pit
W. H. Langer
2011, Aggregates Manager (16) 36-36
A gravel pit that was a source of happy childhood memories showcases the evolution of mining technology....
Informal trail monitoring protocols: Denali National Park and Preserve. Final Report, October 2011
Jeffrey L. Marion, Jeremy F. Wimpey
2011, Report
Managers at Alaska?s Denali National Park and Preserve (DENA) sponsored this research to assess and monitor visitor-created informal trails (ITs). DENA is located in south-central Alaska and managed as a six million acre wilderness park. This program of research was guided by the following objectives: (1) Investigate alternative methods for...
Role of the fish astyanax aeneus (Characidae) as a keystone nutrient recycler in low-nutrient neotropical streams
G. E. Small, C. M. Pringle, M. Pyron, J.H. Duff
2011, Ecology (92) 386-397
Nutrient recycling by animals is a potentially important biogeochemical process in both terrestrial and aquatic ecosystems. Stoichiometric traits of individual species may result in some taxa playing disproportionately important roles in the recycling of nutrients relative to their biomass, acting as keystone nutrient recyclers. We examined factors controlling the relative...
Search for and limits on plume activity on Mimas, Tethys, and Dione with the Cassini Visual Infrared Mapping Spectrometer (VIMS)
B. J. Buratti, S.P. Faulk, J. Mosher, K. H. Baines, R. H. Brown, Randal C. Clark, P. D. Nicholson
2011, Icarus (214) 534-540
Cassini Visual Infrared Mapping Spectrometer (VIMS) observations of Mimas, Tethys, and Dione obtained during the nominal and extended missions at large solar phase angles were analyzed to search for plume activity. No forward scattered peaks in the solar phase curves of these satellites were detected. The upper limit on water vapor...
Declines in deepwater sculpin Myoxocephalus thompsonii energy density associated with the disappearance of Diporeia spp. in lakes Huron and Michigan
S.A. Pothoven, D.W. Hondorp, T.F. Nalepa
2011, Ecology of Freshwater Fish (20) 14-22
The deepwater sculpin Myoxocephalus thompsonii is a glacial relict in the Laurentian Great Lakes that primarily consumes two glacial relict crustaceans, Mysis relicta and Diporeia spp. Deepwater sculpin were collected in Lake Michigan off Little Sable Point (in 2001) and Muskegon, Michigan (in 2001 and 2009), and in Lake Huron...
Analysis of formation pressure test results in the Mount Elbert methane hydrate reservoir through numerical simulation
M. Kurihara, A. Sato, K. Funatsu, H. Ouchi, Y. Masuda, H. Narita, Timothy S. Collett
2011, Marine and Petroleum Geology (28) 502-516
Targeting the methane hydrate (MH) bearing units C and D at the Mount Elbert prospect on the Alaska North Slope, four MDT (Modular Dynamic Formation Tester) tests were conducted in February 2007. The C2 MDT test was selected for history matching simulation in the MH Simulator Code Comparison Study....
Extended megadroughts in the southwestern United States during Pleistocene interglacials
P.J. Fawcett, J.P. Werne, R. Scott Anderson, J.M. Heikoop, E.T. Brown, M.A. Berke, S.J. Smith, F. Goff, L. Donohoo-Hurley, L. M. Cisneros-Dozal, S. Schouten, J.S.S. Damste, Y. Huang, J. Toney, J. Fessenden, G. Woldegabriel, V. Atudorei, J. W. Geissman, Craig D. Allen
2011, Nature (470) 518-521
The potential for increased drought frequency and severity linked to anthropogenic climate change in the semi-arid regions of the southwestern United States (US) is a serious concern. Multi-year droughts during the instrumental period and decadal-length droughts of the past two millennia were shorter and climatically different from the future permanent,...
Are soils of Iowa USA currently a carbon sink or source? Simulated changes in SOC stock from 1972 to 2007
Shuguang Liu, Z. Tan, Z. Li, S. Zhao, W. Yuan
2011, Agriculture, Ecosystems and Environment (140) 106-112
Upscaling the spatial and temporal changes in carbon (C) stocks and fluxes from sites to regions is a critical and challenging step toward improving our understanding of the dynamics of C sources and sinks over large areas. This study simulated soil organic C (SOC) dynamics within 0–100 cm depth of soils...
Examination of core samples from the Mount Elbert Gas Hydrate Stratigraphic Test Well, Alaska North Slope: Effects of retrieval and preservation
T.J. Kneafsey, H. Lu, W. Winters, R. Boswell, R. Hunter, T. S. Collett
2011, Marine and Petroleum Geology (28) 381-393
Collecting and preserving undamaged core samples containing gas hydrates from depth is difficult because of the pressure and temperature changes encountered upon retrieval. Hydrate-bearing core samples were collected at the BPXA-DOE-USGS Mount Elbert Gas Hydrate Stratigraphic Test Well in February 2007. Coring was performed while using a custom oil-based drilling...
Vegetation death and rapid loss of surface elevation in two contrasting Mississippi delta salt marshes: The role of sedimentation, autocompaction and sea-level rise
J.W. Day, G.P. Kemp, D.J. Reed, Donald R. Cahoon, R.M. Boumans, J.M. Suhayda, R. Gambrell
2011, Ecological Engineering (37) 229-240
From 1990 to 2004, we carried out a study on accretionary dynamics and wetland loss in salt marshes surrounding two small ponds in the Mississippi delta; Old Oyster Bayou (OB), a sediment-rich area near the mouth of the Atchafalaya River and Bayou Chitigue (BC), a sediment-poor area about 70 km to the east. The OB site was...
A lognormal distribution of metal resources
Donald A. Singer
2011, Diqiu Kexue - Zhongguo Dizhi Daxue Xuebao/Earth Science - Journal of China University of Geosciences (36) 201-208
For national or global resource estimation of frequencies of metals, a lognormal distribution has commonly been recommended but not adequately tested. Tests of frequencies of Cu, Zn, Pb, Ag, and Au contents of 1 984 well-explored mineral deposits display a poor fit to the lognormal distribution. When the same metals...
Water chemistry and its effects on the physiology and survival of Atlantic salmon Salmo salar smolts
T. Liebich, S. D. McCormick, D. Kircheis, Kevin Johnson, R. Regal, T. Hrabik
2011, Journal of Fish Biology (79) 502-519
The physiological effects of episodic pH fluctuations on Atlantic salmon Salmo salar smolts in eastern Maine, U.S.A., were investigated. During this study, S. salar smolts were exposed to ambient stream‐water chemistry conditions at nine sites in four catchments for 3 and 6 day intervals during the spring S. salar smolt migration period. Plasma chloride, plasma glucose,...
Statistical methods of estimating mining costs
K. R. Long
2011, Conference Paper, SME Annual Meeting and Exhibit and CMA 113th National Western Mining Conference 2011
Until it was defunded in 1995, the U.S. Bureau of Mines maintained a Cost Estimating System (CES) for prefeasibility-type economic evaluations of mineral deposits and estimating costs at producing and non-producing mines. This system had a significant role in mineral resource assessments to estimate costs of developing and operating known...
The influence of the Atlantic Warm Pool on the Florida panhandle sea breeze
V. Misra, L. Moeller, L. Stefanova, S. Chan, J. J. O’Brien, T.J. Smith, N. Plant
2011, Journal of Geophysical Research D: Atmospheres (116)
In this paper we examine the variations of the boreal summer season sea breeze circulation along the Florida panhandle coast from relatively high resolution (10 km) regional climate model integrations. The 23 year climatology (1979-2001) of the multidecadal dynamically downscaled simulations forced by the National Centers for Environmental Prediction-Department of...
Seasonal dripwater Mg/Ca and Sr/Ca variations driven by cave ventilation: Implications for and modeling of speleothem paleoclimate records
C.I. Wong, J.L. Banner, MaryLynn Musgrove
2011, Geochimica et Cosmochimica Acta (75) 3514-3529
A 4-year study in a central Texas cave quantifies multiple mechanisms that control dripwater composition and how these mechanisms vary at different drip sites. We monitored cave-air compositions, in situ calcite growth, dripwater composition and drip rate every 4–6 weeks. Three groups of drip sites are delineated (Groups 1–3) based on...
Regional and climatic controls on seasonal dust deposition in the southwestern U.S.
Marith C. Reheis, Frank Urban
2011, Aeolian Research (3) 3-21
Vertical dust deposition rates (dust flux) are a complex response to the interaction of seasonal precipitation, wind, changes in plant cover and land use, dust source type, and local vs. distant dust emission in the southwestern U.S. Seasonal dust flux in the Mojave–southern Great Basin (MSGB) deserts, measured from 1999...
Effects of acclimation on poststocking dispersal and physiological condition of age-1 pallid sturgeon
E.W. Oldenburg, C.S. Guy, E.S. Cureton, M.A.H. Webb, W.M. Gardner
2011, Journal of Applied Ichthyology (27) 436-443
The objective of this study was to evaluate the effects of acclimation to flow and site‐specific physicochemical water conditions on poststocking dispersal and physiological condition of age‐1 hatchery‐reared pallid sturgeon. Fish from three acclimation treatments were radio‐tagged, released at two locations (Missouri River and Marias River), and monitored using passive...
ASTER spectral analysis and lithologic mapping of the Khanneshin carbonatite volcano, Afghanistan
John C. Mars, Lawrence C. Rowan
2011, Geosphere (7) 276-289
Advanced Spaceborne Thermal and Reflection Radiometer (ASTER) data of the early Quaternary Khanneshin carbonatite volcano located in southern Afghanistan were used to identify carbonate rocks within the volcano and to distinguish them from Neogene ferruginous polymict sandstone and argillite. The carbonatitic rocks are characterized by diagnostic CO3 absorption near 11.2...
Stationarity: Wanted dead or alive?
Harry F. Lins, Timothy A. Cohn
2011, Journal of the American Water Resources Association (47) 475-480
Aligning engineering practice with natural process behavior would appear, on its face, to be a prudent and reasonable course of action. However, if we do not understand the long‐term characteristics of hydroclimatic processes, how does one find the prudent and reasonable course needed for water management? We consider this question...
Associated terrestrial and marine fossils in the late-glacial Presumpscot Formation, southern Maine, USA, and the marine reservoir effect on radiocarbon ages
W.B. Thompson, C.B. Griggs, N.G. Miller, R.E. Nelson, T.K. Weddle, T.M. Kilian
2011, Quaternary Research (75) 552-565
Excavations in the late-glacial Presumpscot Formation at Portland, Maine, uncovered tree remains and other terrestrial organics associated with marine invertebrate shells in a landslide deposit. Buds of Populus balsamifera (balsam poplar) occurred with twigs of Picea glauca (white spruce) in the Presumpscot clay. Tree rings in Picea logs indicate that the trees all...
Continuity of Landsat observations: Short term considerations
Michael A. Wulder, Joanne C. White, Jeffery G. Masek, John L. Dwyer, David P. Roy
2011, Remote Sensing of Environment (115) 747-751
As of writing in mid-2010, both Landsat-5 and -7 continue to function, with sufficient fuel to enable data collection until the launch of the Landsat Data Continuity Mission (LDCM) scheduled for December of 2012. Failure of one or both of Landsat-5 or -7 may result in a lack of Landsat...
Are secular correlations between sunspots, geomagnetic activity, and global temperature significant?
Jeffrey J. Love, K. Mursula, V.C. Tsai, D. M. Perkins
2011, Geophysical Research Letters (38)
Recent studies have led to speculation that solar‐terrestrial interaction, measured by sunspot number and geomagnetic activity, has played an important role in global temperature change over the past century or so. We treat this possibility as an hypothesis for testing. We examine the statistical significance of cross‐correlations between sunspot number,...
Comparison of Bayesian clustering and edge detection methods for inferring boundaries in landscape genetics
T. Safner, Mark P. Miller, B.H. McRae, M.-J. Fortin, S. Manel
2011, International Journal of Molecular Sciences (12) 865-889
Recently, techniques available for identifying clusters of individuals or boundaries between clusters using genetic data from natural populations have expanded rapidly. Consequently, there is a need to evaluate these different techniques. We used spatially-explicit simulation models to compare three spatial Bayesian clustering programs and two edge detection methods. Spatially-structured populations...
Spatial connectivity in a highly heterogeneous aquifer: From cores to preferential flow paths
M. Bianchi, C. Zheng, C. Wilson, G.R. Tick, Gaisheng Liu, S.M. Gorelick
2011, Water Resources Research (47)
This study investigates connectivity in a small portion of the extremely heterogeneous aquifer at the Macrodispersion Experiment (MADE) site in Columbus, Mississippi. A total of 19 fully penetrating soil cores were collected from a rectangular grid of 4 m by 4 m. Detailed grain size analysis was performed on 5...
Hepatic element concentrations of lesser scaup (Aythya affinis) during spring migration in the upper Midwest
Angela E. Pillatzki, Regg D. Neiger, Steven R. Chipps, Kenneth F. Higgins, Nancy Thiex, Alan D. Afton
2011, Archives of Environmental Contamination and Toxicology (61) 144-150
High concentrations of some hepatic elements might be contributing to the decline of the continental lesser scaup (Aythya affinis) population. We evaluated hepatic element concentrations of male and female lesser scaup collected from the upper Midwest (Iowa, Minnesota, North Dakota, and South Dakota) during the 2003 and 2004 spring migrations....
