Fluid inclusion and noble gas studies of the Dongping gold deposit, Hebei Province, China: A mantle connection for mineralization?
J. Mao, Y. Li, R. Goldfarb, Y. He, K. Zaw
2003, Economic Geology (98) 517-534
The Dongping gold deposit (>100 t Au) occurs about 200 km inboard of the northern margin of the North China craton. The deposit is mainly hosted by syenite of a middle Paleozoic alkalic intrusive complex that was emplaced into Late Archean basement rocks. Both groups of rocks are intruded by...
Inorganic nitrogen transformations in the bed of the Shingobee River, Minnesota: Integrating hydrologic and biological processes using sediment perfusion cores
R.W. Sheibley, J.H. Duff, A. P. Jackman, F.J. Triska
2003, Limnology and Oceanography (48) 1129-1140
Inorganic N transformations were examined in streambed sediments from the Shingobee River using sediment perfusion cores. The experimental design simulated groundwater-stream water mixing within sediment cores, which provided a well-defined one-dimensional representation of in situ hydrologic conditions. Two distinct hydrologic and chemical settings were preserved in the sediment cores: the...
Simplified method for detecting tritium contamination in plants and soil
Brian J. Andraski, Mark W. Sandstrom, R. L. Michel, J.C. Radyk, David A. Stonestrom, M. J. Johnson, C.J. Mayers
2003, Journal of Environmental Quality (32) 988-995
Cost-effective methods are needed to identify the presence and distribution of tritium near radioactive waste disposal and other contaminated sites. The objectives of this study were to (i) develop a simplified sample preparation method for determining tritium contamination in plants and (ii) determine if plant data could be used as...
Estimating population trends with a linear model
Jonathan Bart, Brian D. Collins, R. I. G. Morrison
2003, The Condor (105) 367-372
We describe a simple and robust method for estimating trends in population size. The method may be used with Breeding Bird Survey data, aerial surveys, point counts, or any other program of repeated surveys at permanent locations. Surveys need not be made at each location during each survey period. The...
Middle Devonian to Early Carboniferous event stratigraphy of Devils Gate and Northern Antelope Range sections, Nevada, U.S.A
Charles Sandberg, J. R. Morrow, F. G. Poole, W. Ziegler
2003, CFS Courier Forschungsinstitut Senckenberg 187-207
The classic type section of the Devils Gate Limestone at Devils Gate Pass is situated on the eastern slope of a proto-Antler forebulge that resulted from convergence of the west side of the North American continent with an ocean plate. The original Late Devonian forebulge, the site of which is...
Resurfacing history of the northern plains of Mars based on geologic mapping of Mars Global Surveyor data
Kenneth L. Tanaka, James A. Skinner, Trent M. Hare, T. Joyal, A. Wenker
2003, Journal of Geophysical Research E: Planets (108)
Geologic mapping of the northern plains of Mars, based on Mars Orbiter Laser Altimeter topography and Viking and Mars Orbiter Camera images, reveals new insights into geologic processes and events in this region during the Hesperian and Amazonian Periods. We propose four successive stages of lowland resurfacing likely related to...
Geomedia: Mapping Colorado at a fine scale
R. Orndorff
2003, Geotimes (48) 36-37
Currently, only 24 percent of Colorado's spectacular geology has been mapped at the fine scale of 1:24,000. At the same time, the state hosts many geologic hazards. Most maps of Colorado are at much broader scales, failing to show detail of basic geology crucial to safe engineering and building practices...
Hydrothermal and tectonic activity in northern Yellowstone Lake, Wyoming
S. Y. Johnson, W. J. Stephenson, L. A. Morgan, Wayne C. Shanks, K. L. Pierce
2003, Geological Society of America Bulletin (115) 954-971
Yellowstone National Park is the site of one of the world's largest calderas. The abundance of geothermal and tectonic activity in and around the caldera, including historic uplift and subsidence, makes it necessary to understand active geologic processes and their associated hazards. To that end, we here use an extensive...
Gyrfalcon diet in central west Greenland during the nesting period
T.L. Booms, M.R. Fuller
2003, Condor (105) 528-537
We studied food habits of Gyrfalcons (Falco rusticolus) nesting in central west Greenland in 2000 and 2001 using three sources of data: time-lapse video (3 nests), prey remains (22 nests), and regurgitated pellets (19 nests). These sources provided different information describing the diet during the nesting period. Gyrfalcons relied heavily...
An evaluation of selective feeding by three age-groups of the rainbow mussel Villosa iris
K. Beck, R. J. Neves
2003, North American Journal of Aquaculture (65) 203-209
A tri-algal diet was fed to three age-groups of the rainbow mussel Villosa iris: ages 2-3 d, 50-53 d, and 3-6 years. Changes in the relative abundance of each algal species were determined in 5-h feeding trials from feeding chambers and by gut content analyses. All age-groups rejected Scenedesmus quadricauda...
Development of a multimetric index for assessing the biological condition of the Ohio River
E.B. Emery, T.P. Simon, F.H. McCormick, P. L. Angermeier, J.E. Deshon, C.O. Yoder, R.E. Sanders, W.D. Pearson, G.D. Hickman, R.J. Reash, J.A. Thomas
2003, Transactions of the American Fisheries Society (132) 791-808
The use of fish communities to assess environmental quality is common for streams, but a standard methodology for large rivers is as yet largely undeveloped. We developed an index to assess the condition of fish assemblages along 1,580 km of the Ohio River. Representative samples of fish assemblages were collected...
A Visual Basic program to classify sediments based on gravel-sand-silt-clay ratios
L.J. Poppe, A.H. Eliason, M. E. Hastings
2003, Computers & Geosciences (29) 805-809
Nomenclature describing size distributions is important to geologists because grain size is the most basic attribute of sediments. Traditionally, geologists have divided sediments into four size fractions that include gravel, sand, silt, and clay, and classified these sediments based on ratios of the various proportions of the fractions. Definitions of...
Some observations on colocated and closely spaced strong ground-motion records of the 1999 Chi-Chi, Taiwan, earthquake
G.-Q. Wang, D.M. Boore, H. Igel, X.-Y. Zhou
2003, Bulletin of the Seismological Society of America (93) 674-693
The digital accelerograph network installed in Taiwan produced a rich set of records from the 20 September 1999 Chi-Chi, Taiwan earthquake (Mw 7.6). Teledyne Geotech model A-800 and A-900A* digital accelerographs were colocated at 22 stations that recorded this event. Comparisons of the amplitudes, frequency content, and baseline offsets show...
Application of a multipurpose unequal probability stream survey in the Mid-Atlantic Coastal Plain
S.W. Ator, A.R. Olsen, A.M. Pitchford, J. M. Denver
2003, Journal of the American Water Resources Association (39) 873-885
A stratified, spatially balanced sample with unequal probability selection was used to design a multipurpose survey of headwater streams in the Mid-Atlantic Coastal Plain. Objectives for the survey include unbiased estimates of regional stream conditions, and adequate coverage of unusual but significant environmental settings to support empirical modeling of the...
An empirical approach to inversion of an unconventional helicopter electromagnetic dataset
L. Pellerin, V.F. Labson
2003, Journal of Applied Geophysics (53) 49-61
A helicopter electromagnetic (HEM) survey acquired at the U.S. Idaho National Engineering and Environmental Laboratory (INEEL) used a modification of a traditional mining airborne method flown at low levels for detailed characterization of shallow waste sites. The low sensor height, used to increase resolution, invalidates standard assumptions used in processing...
Impacts of the Columbia River hydroelectric system on main-stem habitats of fall chinook salmon
D.D. Dauble, T.P. Hanrahan, D.R. Geist, M.J. Parsley
2003, North American Journal of Fisheries Management (23) 641-659
Salmonid habitats in main-stem reaches of the Columbia and Snake rivers have changed dramatically during the past 60 years because of hydroelectric development and operation. Only about 13% and 58% of riverine habitats in the Columbia and Snake rivers, respectively, remain. Most riverine habitat is found in the upper Snake...
Bayesian Estimations of Peak Ground Acceleration and 5% Damped Spectral Acceleration from Modified Mercalli Intensity Data
J.E. Ebel, D.J. Wald
2003, Earthquake Spectra (19) 511-529
We describe a new probabilistic method that uses observations of modified Mercalli intensity (MMI) from past earthquakes to make quantitative estimates of ground shaking parameters (i.e., peak ground acceleration, peak ground velocity, 5% damped spectral acceleration values, etc.). The method uses a Bayesian approach to make quantitative estimates of the...
Modeling Np and Pu transport with a surface complexation model and spatially variant sorption capacities: Implications for reactive transport modeling and performance assessments of nuclear waste disposal sites
P. D. Glynn
2003, Computers & Geosciences (29) 331-349
One-dimensional (1D) geochemical transport modeling is used to demonstrate the effects of speciation and sorption reactions on the ground-water transport of Np and Pu, two redox-sensitive elements. Earlier 1D simulations (Reardon, 1981) considered the kinetically limited dissolution of calcite and its effect on ion-exchange reactions (involving 90Sr, Ca, Na, Mg and...
Challenges to reestablishment of free-ranging populations of black-footed ferrets
E. Biggins, Jerry L. Godbey
2003, Comptes Rendus - Biologies (326) 104-111
The black-footed ferret (Mustela nigripes) of North America is critically endangered due in part to its extreme specialization on formerly stable and abundant prairie dogs (Cynomys). Its close relative, the Siberian polecat (M. eversmannii) seems to have been subjected to a varying environment that was not conducive to specialization. One source of environmental variation in Asian steppes was...
The Meteoritical Bulletin, No. 87, 2003 July
Sara S. Russell, J. Zipfel, L. Folco, R. Jones, Monica M. Grady, T. McCoy, Jeffrey N. Grossman
2003, Meteoritics and Planetary Science (38) A189-A248
Meteoritical Bulletin No. 87 lists information for 1898 newly classified meteorites, comprising 1048 from Antarctica, 462 from Africa, 356 from Asia (355 of which are from Oman), 18 from North America, 5 from South America, 5 from Europe, and 3 from Australia. Information is provided for 10 falls (Beni M'hira,...
Regional flood probabilities
Brent M. Troutman, Michael R. Karlinger
2003, Water Resources Research (39) 4-1-4-15
The T‐year annual maximum flood at a site is defined to be that streamflow, that has probability 1/T of being exceeded in any given year, and for a group of sites the corresponding regional flood probability (RFP) is the probability that at least one site will experience a T‐year flood in any given...
Determining extreme parameter correlation in ground water models.
M. C. Hill, O. Osterby
2003, Ground Water (41) 420-430
In ground water flow system models with hydraulic-head observations but without significant imposed or observed flows, extreme parameter correlation generally exists. As a result, hydraulic conductivity and recharge parameters cannot be uniquely estimated. In complicated problems, such correlation can go undetected even by experienced modelers. Extreme parameter correlation can be...
Bedded jaspers of the Ordovician Løkken ophiolite, Norway: seafloor deposition and diagenetic maturation of hydrothermal plume-derived silica-iron gels
Tor Grenne, John F. Slack
2003, Mineralium Deposita (38) 625-639
Sedimentary beds of jasper (red hematitic chert) in the Ordovician Løkken ophiolite of Norway are closely associated with volcanogenic massive sulphide (VMS) deposits. The jaspers occur in the immediate hangingwall and laterally peripheral to the large Løkken (25–30 Mt) and small Høydal (0.1 Mt) VMS deposits, and are exposed discontinuously for...
Avian use of natural versus planted woodlands in eastern South Dakota, USA
Kristel K. Bakker, Kenneth F. Higgins
2003, Natural Areas Journal (23) 121-128
We compared avian use of naturally occurring and planted woodlands in eastern South Dakota, USA, to evaluate whether planted woodlands support the same avian communities as natural woodlands. A stratified cluster sample was used to randomly select 307 public areas in which to survey planted (n = 425) and natural...
Excess nitrogen in selected thermal and mineral springs of the Cascade Range in northern California, Oregon, and Washington: Sedimentary or volcanic in origin?
Robert H. Mariner, William C. Evans, T. S. Presser, L. D. White
2003, Journal of Volcanology and Geothermal Research (121) 99-114
Anomalous N2/Ar values occur in many thermal springs and mineral springs, some volcanic fumaroles, and at least one acid-sulfate spring of the Cascade Range. Our data show that N2/Ar values are as high as 300 in gas from some of the hot springs, as...
