Publications
These publications showcase the significant science conducted in our Science Centers.
Filter Total Items: 16727
Exploration review Exploration review
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...
Authors
D.R. Wilburn, T.D. Rapstine, E.C. Lee
Magnesium compounds Magnesium compounds
Seawater and natural brines accounted for about 57 percent of magnesium compounds produced in the United States in 2011. Dead-burned magnesia was produced by Martin Marietta Magnesia Specialties LLC from well brines in Michigan. Caustic-calcined magnesia was recovered from seawater by Premier Magnesia LLC in Florida, from well brines in Michigan by Martin Marietta and from magnesite in...
Authors
D.A. Kramer
GONe: Software for estimating effective population size in species with generational overlap GONe: Software for estimating effective population size in species with generational overlap
GONe is a user‐friendly, Windows‐based program for estimating effective size (Ne) in populations with overlapping generations. It uses the Jorde–Ryman modification to the temporal method to account for age structure in populations. This method requires estimates of age‐specific survival and birth rate and allele frequencies measured in two or more consecutive cohorts. Allele frequencies...
Authors
J.A. Coombs, B.H. Letcher, K.H. Nislow
The Hydrothermal Diamond Anvil Cell (HDAC) for raman spectroscopic studies of geologic fluids at high pressures and temperatures The Hydrothermal Diamond Anvil Cell (HDAC) for raman spectroscopic studies of geologic fluids at high pressures and temperatures
In this chapter, we describe the hydrothermal diamond-anvil cell (HDAC), which is specifically designed for experiments on systems with aqueous fluids to temperatures up to ⬚~1000ºC and pressures up to a few GPa to tens of GPa. This cell permits optical observation of the sample and the in situ determination of properties by ‘photon-in photon-out’ techniques such as Raman spectroscopy...
Authors
Christian Schmidt, I-Ming Chou
Hierarchical spatial structure of stream fish colonization and extinction Hierarchical spatial structure of stream fish colonization and extinction
Spatial variation in extinction and colonization is expected to influence community composition over time. In stream fish communities, local species richness (alpha diversity) and species turnover (beta diversity) are thought to be regulated by high extinction rates in headwater streams and high colonization rates in downstream areas. We evaluated the spatiotemporal structure of fish...
Authors
N.P. Hitt, J.H. Roberts
Evaluation of Bayesian estimation of a hidden continuous-time Markov chain model with application to threshold violation in water-quality indicators Evaluation of Bayesian estimation of a hidden continuous-time Markov chain model with application to threshold violation in water-quality indicators
Natural resource managers require information concerning the frequency, duration, and long-term probability of occurrence of water-quality indicator (WQI) violations of defined thresholds. The timing of these threshold crossings often is hidden from the observer, who is restricted to relatively infrequent observations. Here, a model for the hidden process is linked with a model for the
Authors
Frank A. Deviney, Karen C. Rice, Donald E. Brown
Balancing precision and risk: should multiple detection methods be analyzed separately in N-mixture models? Balancing precision and risk: should multiple detection methods be analyzed separately in N-mixture models?
Using multiple detection methods can increase the number, kind, and distribution of individuals sampled, which may increase accuracy and precision and reduce cost of population abundance estimates. However, when variables influencing abundance are of interest, if individuals detected via different methods are influenced by the landscape differently, separate analysis of multiple...
Authors
Tabitha A. Graves, J. Andrew Royle, Katherine C. Kendall, Paul Beier, Jeffrey B. Stetz, Amy C. Macleod
Strategies for soil quality assessment using VNIR gyperspectral spectroscopy in a western Kenya Chronosequence Strategies for soil quality assessment using VNIR gyperspectral spectroscopy in a western Kenya Chronosequence
Visible and near-infrared reflectance spectroscopy (VNIRS) is a rapid and nondestructive method that can predict multiple soil properties simultaneously, but its application in multidimensional soil quality (SQ) assessment in the tropics still needs to be further assessed. In this study, VNIRS (350–2500 nm) was employed to analyze 227 air-dried soil samples of Ultisols from a soil...
Authors
Rintaro Kinoshita, Bianca N. Moebius-Clune, Harold M. van Es, W. Dean Hively, A. Volkan Bilgilis
Step-changes in the physical, chemical and biological characteristics of the Gulf of Maine, as documented by the GNATS time series Step-changes in the physical, chemical and biological characteristics of the Gulf of Maine, as documented by the GNATS time series
We identify step-changes in the physical, chemical and biological characteristics of the Gulf of Maine (GoM) using the Gulf of Maine North Atlantic Time Series (GNATS), a series of oceanographic measurements obtained between September 1998 and December 2010 along a transect in the GoM running from Portland, ME, to Yarmouth, NS. GNATS sampled a period of extremes in precipitation and...
Authors
William M. Balch, D.T. Drapeau, B.C. Bowler, Thomas G. Huntington
A major light rare-earth element (LREE) resource in the Khanneshin carbonatite complex, southern Afghanistan A major light rare-earth element (LREE) resource in the Khanneshin carbonatite complex, southern Afghanistan
The rapid rise in world demand for the rare-earth elements (REEs) has expanded the search for new REE resources. We document two types of light rare-earth element (LREE)-enriched rocks in the Khanneshin carbonatite complex of southern Afghanistan: type 1 concordant seams of khanneshite-(Ce), synchysite-(Ce), and parisite-(Ce) within banded barite-strontianite alvikite, and type 2 igneous...
Authors
Robert D. Tucker, Harvey E. Belkin, Klaus J. Schulz, Stephen G. Peters, Forrest Horton, Kim Buttleman, Emily R. Scott
Estrogenic compounds decrease growth hormone receptor abundance and alter osmoregulation in Atlantic salmon Estrogenic compounds decrease growth hormone receptor abundance and alter osmoregulation in Atlantic salmon
Exposure of Atlantic salmon smolts to estrogenic compounds is shown to compromise several aspects of smolt development. We sought to determine the underlying endocrine mechanisms of estrogen impacts on the growth hormone (GH)/insulin-like growth factor I (IGF-I) axis. Smolts in freshwater (FW) were either injected 3 times over 10 days with 2 μg g−1 17β-estradiol (E2) or 150 μg g−1 4...
Authors
Darren T. Lerner, Mark A. Sheridan, Stephen D. McCormick
Development of polysomic microsatellite markers for characterization of population structuring and phylogeography in the shortnose sturgeon (Acipenser brevirostrum) Development of polysomic microsatellite markers for characterization of population structuring and phylogeography in the shortnose sturgeon (Acipenser brevirostrum)
Shortnose sturgeon Acipenser brevirostrum is an endangered polyploid fish species for which no nuclear DNA markers previously existed. To address this need, 86 polysomic loci were developed and characterized in 20 A. brevirostrum from five river systems and eight members (parents and six progeny) of a captive-bred family. All markers proved to be polymorphic, polysomic, and demonstrated...
Authors
Anne P. Henderson, Tim L. King