Geochemistry, radiocarbon ages, and paleorecharge conditions along a transect in the central High Plains aquifer, southwestern Kansas, USA
P.B. McMahon, J.K. Böhlke, S. C. Christenson
2004, Applied Geochemistry (19) 1655-1686
Water samples from short-screen monitoring wells installed along a 90-km transect in southwestern Kansas were analyzed for major ions, trace elements, isotopes (H, B, C, N, O, S, Sr), and dissolved gases (He, Ne, N2, Ar, O2, CH4) to evaluate the geochemistry, radiocarbon ages, and paleorecharge conditions in the unconfined...
Assessing subglacial processes from diatom fragmentation patterns
R.P. Scherer, C.M. Sjunneskog, N.R. Iverson, T.S. Hooyer
2004, Geology (32) 557-560
Reconstructing the size and glacial style of past ice-sheet advances requires interpreting complex glacial sedimentary facies. We use diatoms, a major component of Antarctic continental shelf deposits, to infer the physical conditions under which these deposits were emplaced. The degree of diatom fragmentation and the presence of diatoms of varying...
The opportunity Rover's Athena science investigation at Meridiani Planum, Mars
S. W. Squyres, R. E. Arvidson, J.F. Bell III, J. Bruckner, N.A. Cabrol, W. Calvin, M. H. Carr, P. R. Christensen, B. C. Clark, L. Crumpler, D.J. Des Marais, C. D'Uston, T. Economou, J. Farmer, W. Farrand, W. Folkner, M. Golombek, S. Gorevan, J. A. Grant, R. Greeley, J. Grotzinger, L. Haskin, Kenneth E. Herkenhoff, S. Hviid, J. Johnson, G. Klingelhofer, A.H. Knoll, G. Landis, M. Lemmon, R. Li, M.B. Madsen, M. C. Malin, S. M. McLennan, H.Y. McSween, D. W. Ming, J. Moersch, R.V. Morris, T. Parker, J. W. Rice Jr., L. Richter, R. Rieder, M. Sims, M. Smith, P. Smith, Laurence A. Soderblom, R. Sullivan, H. Wanke, T. Wdowiak, M. Wolff, A. Yen
2004, Science (306) 1698-1703
The Mars Exploration Rover Opportunity has investigated the landing site in Eagle crater and the nearby plains within Meridiani Planum. The soils consist of fine-grained basaltic sand and a surface lag of hematite-rich spherules, spherule fragments, and other granules. Wind ripples are common. Underlying the thin soil layer, and exposed...
A GIS analysis of suitability for construction aggregate recycling sites using regional transportation network and population density features
G.R. Robinson Jr., K. E. Kapo
2004, Resources, Conservation and Recycling (42) 351-365
Aggregate is used in road and building construction to provide bulk, strength, support, and wear resistance. Reclaimed asphalt pavement (RAP) and reclaimed Portland cement concrete (RPCC) are abundant and available sources of recycled aggregate. In this paper, current aggregate production operations in Virginia, Maryland, and the District of Columbia are...
Threatened fishes of the world: Notropis topeka Gilbert, 1884 (Cyprinidae)
S.S. Wall, C. R. Berry Jr.
2004, Environmental Biology of Fishes (70) 246
[No abstract available]...
Simulation of ventilation efficiency, and pre-closure temperatures in emplacement drifts at Yucca Mountain, Nevada, using Monte Carlo and composite thermal-pulse methods
J.B. Case, D.C. Buesch
2004, Conference Paper, Proceedings of the ASME Heat Transfer/Fluids Engineering Summer Conference 2004, HT/FED 2004
Predictions of waste canister and repository driftwall temperatures as functions of space and time are important to evaluate pre-closure performance of the proposed repository for spent nuclear fuel and high-level radioactive waste at Yucca Mountain, Nevada. Variations in the lithostratigraphic features in densely welded and crystallized rocks of the 12.8-million-year-old...
A project summary: Water and energy budget assessment for a non-tidal wetland in the Sacramento-San Joaquin delta
Frank E. Anderson, R.L. Snyder, U.K.T. Paw, Judith Z. Drexler
2004, Conference Paper, 26th Conference on Agricultural and Forest Meteorology
The methods used to obtain universal cover coefficient (Kc) values for a non-tidal restored wetland in the Sacramento-San Joaquin river delta, US, during the summer of the year 2002 and to investigate possible differences during changing wind patterns are described. A micrometeorological tower over the wetland was established to quantify...
A high resolution record of chlorine-36 nuclear-weapons-tests fallout from Central Asia
J.R. Green, L.D. Cecil, H.-A. Synal, J. Santos, K.J. Kreutz, C.P. Wake
2004, Conference Paper, Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms
The Inilchek Glacier, located in the Tien Shan Mountains, central Asia, is unique among mid-latitude glaciers because of its relatively large average annual accumulation. In July 2000, two ice cores of 162 and 167 meters (m) in length were collected from the Inilchek Glacier for (chlorine-36) 36Cl analysis a part...
Global geologic context for rock types and surface alteration on Mars
M.B. Wyatt, H.Y. McSween Jr., K. L. Tanaka, J. W. Head III
2004, Geology (32) 648-654
Petrologic interpretations of thermal emission spectra from Mars orbiting spacecraft indicate the widespread occurrence of surfaces having basaltic and either andesitic or partly altered basalt compositions. Global concentration of ice-rich mantle deposits and near-surface ice at middle to high latitudes and their spatial correlation with andesitic or partly altered basalt...
New constraints on the sources and behavior of neodymium and hafnium in seawater from Pacific Ocean ferromanganese crusts
T. van de Flierdt, M. Frank, D.-C. Lee, A. N. Halliday, B.C. Reynolds, J.R. Hein
2004, Geochimica et Cosmochimica Acta (68) 3827-3843
The behavior of dissolved Hf in the marine environment is not well understood due to the lack of direct seawater measurements of Hf isotopes and the limited number of Hf isotope time-series obtained from ferromanganese crusts. In order to place better constraints on input sources and develop further applications, a...
Drainage effects on stream nitrate-N and hydrology in south-central Minnesota (USA)
J.A. Magner, G. A. Payne, J. Steffen
2004, Environmental Monitoring and Assessment (91) 183-198
Excessive nitrate-N in south-central Minnesota ditches and streams is related to land-use change, and may be contributing to the development of the zone of hypoxia in the Gulf of Mexico. Intensive land-use (agricultural management) has progressively increased as subsurface drainage has improved crop productivity over the past 25 years. We...
Wave run-up on a high-energy dissipative beach
P. Ruggiero, R.A. Holman, R.A. Beach
2004, Journal of Geophysical Research C: Oceans (109)
Because of highly dissipative conditions and strong alongshore gradients in foreshore beach morphology, wave run-up data collected along the central Oregon coast during February 1996 stand in contrast to run-up data currently available in the literature. During a single data run lasting approximately 90 min, the significant vertical run-up elevation...
A guide to the Mule Creek volcanic vent, the rhyolite of Potholes Country, and obsidian ledges, Gila National Forest, southwestern New Mexico
J.C. Ratte
2004, New Mexico Geology (26) 111-122
[No abstract available]...
Element content of Xanthoparmelia scabrosa growing on asphalt in urban and rural New Zealand
J. P. Bennett, D.M. Wright
2004, Bryologist (107) 421-428
Xanthoparmelia scabrosa is a foliose lichen that grows abundantly on pedestrian and automobile asphalt in New Zealand, which are considered inhospitable habitats for lichens. Samples were collected at eight localities ranging from urban streets to very rural roads and analyzed for 28 chemical elements in order to determine elemental chemistry...
The future of fire in California ecosystems
N. G. Sugihara, J. W. van Wagtendonk, J. Fites-Kaufman, K. E. Shaffer, A. E. Thode
N. G. Sugihara, J. W. van Wagtendonk, J. Fites-Kaufman, K. E. Shaffer, A. E. Thode, editor(s)
2004, Book chapter, Fire in California ecosystems
This chapter reviews the concepts developed in the book and challenges Californians to accept the fact that they live in fire-prone ecosystems. California’s variety of fire regimes are products of its wide diversity of vegetation, climate, topography, and ignitions. The role fire plays in an ecosystem is characterized by the...
The effects of habitat resolution on models of avian diversity and distributions: A comparison of two land-cover classifications
Joshua J. Lawler, Raymond. J. O’Connor, Carolyn T. Hunsaker, K. Bruce Jones, Thomas R. Loveland, Denis White
2004, Landscape Ecology (19) 517-532
Quantifying patterns is a key element of landscape analysis. One aspect of this quantification of particular importance to landscape ecologists is the classification of continuous variables to produce categorical variables such as land-cover type or elevation stratum. Although landscape ecologists are fully aware of the importance of spatial resolution in...
Tectonic histories between Alba Patera and Syria Planum, Mars
R. C. Anderson, J. M. Dohm, A. F. C. Haldemann, T.M. Hare, V.R. Baker
2004, Icarus (171) 31-38
Syria Planum and Alba Patera are two of the most prominent features of magmatic-driven activity identified for the Tharsis region and perhaps for all of Mars. In this study, we have performed a Geographic Information System-based comparative investigation of their tectonic histories using published geologic map information and Mars Orbiter...
Coastal wetlands of the Laurentian Great Lakes: Summary and future directions
T. Mayer, T. Edsall, M. Munawar
2004, Conference Paper, Aquatic Ecosystem Health and Management
[No abstract available]...
Age of Palos Verdes submarine debris avalanche, southern California
W. R. Normark, M. McGann, R. Sliter
2004, Conference Paper, Marine Geology
The Palos Verdes debris avalanche is the largest, by volume, late Quaternary mass-wasted deposit recognized from the inner California Borderland basins. Early workers speculated that the sediment failure giving rise to the deposit is young, taking place well after sea level reached its present position. A newly acquired, closely-spaced grid...
Spatial and temporal variation of Cenozoic surface elevation in the Great Basin and Sierra Nevada
T.W. Horton, D.J. Sjostrom, M.J. Abruzzese, M.A. Poage, J.R. Waldbauer, M. Hren, J. Wooden, C. P. Chamberlain
2004, American Journal of Science (304) 862-888
The surface uplift of mountain belts caused by tectonism plays an important role in determining the long-term climate evolution of the Earth. However, the general lack of information on the paleotopography of mountain belts limits our ability to identify the links and feedbacks between topography, tectonics, and climate change on...
Bioturbation depths, rates and processes in Massachusetts Bay sediments inferred from modeling of 210Pb and 239 + 240Pu profiles
John Crusius, Michael H. Bothner, Christopher K. Sommerfield
2004, Estuarine, Coastal and Shelf Science (61) 643-655
Profiles of 210Pb and 239 + Pu from sediment cores collected throughout Massachusetts Bay (water depths of 36-192 m) are interpreted with the aid of a numerical sediment-mixing model to infer bioturbation depths, rates and processes. The nuclide data suggest extensive bioturbation to depths of 25-35 cm. Roughly half the...
Mercury content of Illinois soils
G.B. Dreher, L.R. Follmer
2004, Water, Air, & Soil Pollution (156) 299-315
For a survey of Illinois soils, 101 cores had been collected and analyzed to determine the current and background elemental compositions of Illinois soils. Mercury and other elements were determined in six samples per core, including a surface sample from each core. The mean mercury content in the surface samples...
Investigation of differences between field and laboratory pH measurements of national atmospheric deposition program/national trends network precipitation samples
N. Latysh, J. Gordon
2004, Water, Air, & Soil Pollution (154) 249-270
A study was undertaken to investigate differences between laboratory and field pH measurements for precipitation samples collected from 135 weekly precipitation-monitoring sites in the National Trends Network from 12/30/1986 to 12/28/1999. Differences in pH between field and laboratory measurements occurred for 96% of samples collected during this time period. Differences...
Carbon dioxide transport over complex terrain
Jielun Sun, Sean P. Burns, A.C. Delany, S.P. Oncley, A. Turnipseed, B. Stephens, A. Guenther, D.E. Anderson, R. Monson
2004, Conference Paper, 26th Conference on Agricultural and Forest Meteorology
The nocturnal transport of carbon dioxide over complex terrain was investigated. The high carbon dioxide under very stable conditions flows to local low-ground. The regional drainage flow dominates the carbon dioxide transport at the 6 m above the ground and carbon dioxide was transported to the regional low ground. The...
A teleseismic study of the 2002 Denali fault, Alaska, earthquake and implications for rapid strong-motion estimation
C. Ji, D.V. Helmberger, D.J. Wald
2004, Earthquake Spectra (20) 617-637
Slip histories for the 2002 M7.9 Denali fault, Alaska, earthquake are derived rapidly from global teleseismic waveform data. In phases, three models improve matching waveform data and recovery of rupture details. In the first model (Phase I), analogous to an automated solution, a simple fault plane is fixed based on...
