Grooved Terrain on Ganymede: First Results from Galileo High-Resolution Imaging
Robert T. Pappalardo, James W. Head, Geoffrey C. Collins, Randolph L. Kirk, Gerhard Neukum, Jurgen Oberst, Bernd Giese, Ronald Greeley, Clark R. Chapman, Paul Helfenstein, Jeffrey M. Moore, Alfred S. McEwen, B. Randy Tufts, David A. Senske, H. Herbert Breneman, Kenneth P. Klaasen
1998, Icarus (135) 276-302
High-resolution Galileo imaging has provided important insight into the origin and evolution of grooved terrain on Ganymede. The Uruk Sulcus target site was the first imaged at high resolution, and considerations of resolution, viewing geometry, low image compression, and complementary stereo imaging make this region extremely informative. Contrast variations in...
The geochemical record in rock glaciers
E.J. Steig, J. J. Fitzpatrick, N. Potter Jr., D.H. Clark
1998, Geografiska Annaler, Series A: Physical Geography (80) 277-286
A 9.5 m ice core was extracted from beneath the surficial debris cover of a rock glacier at Galena Creek, northwestern Wyoming. The core contains clean, bubble-rich ice with silty debris layers spaced at roughly 20 cm intervals. The debris layers are similar in appearance...
Soil carbon stocks and their rates of accumulation and loss in a boreal forest landscape
G. Rapalee, S.E. Trumbore, E.A. Davidson, Jennifer W. Harden, H. Veldhuis
1998, Global Biogeochemical Cycles (12) 687-701
Boreal forests and wetlands are thought to be significant carbon sinks, and they could become net C sources as the Earth warms. Most of the C of boreal forest ecosystems is stored in the moss layer and in the soil. The objective of this study was to estimate soil C...
Cultural resource applications for a GIS: Stone conservation at Jefferson and Lincoln Memorials
Kyle Joly, Tony Donald, Douglas Comer
1998, Cultural Resources Management (21) 17-18
Geographical information systems are rapidly becoming essential tools for land management. They provide a way to link landscape features to the wide variety of information that managers must consider when formulating plans for a site, designing site improvement and restoration projects, determining maintenance projects and protocols, and even interpreting the...
Modeling spatial distribution of the Unionid mussels and the core-satellite hypothesis
Hooi-Ling Lee, Donald L. DeAngelis, Hock Lye Koh
1998, Water Science and Technology (38) 73-79
This paper discusses the spatial distribution patterns of the various species of the Unionid mussels as functions of their respective life-cycle characteristics. Computer simulations identify two life-cycle characteristics as major factors governing the abundance of a species, namely the movement range of their fish hosts and the success rate of...
Fire, vegetation, and scale: Toward optimal models for the Pacific Northwest
D. McKenzie
1998, Northwest Science (72) 49-65
No abstract available....
Application of an index of biotic integrity for dunal, palustrine wetlands: Emphasis on assessment of nonpoint source landfill effects on the Grand Calumet Lagoons
T.P. Simon, P.M. Stewart
1998, Aquatic Ecosystem Health & Management (1) 63-74
Using a newly modified index of biotic integrity for assessing biological integrity of fish communities in dunal, palustrine wetlands, we assessed the non-point source influence of an industrial landfill on the Grand Calumet Lagoons. The landfill is primarily an iron and steel manufacturer's slag waste. No sensitive species, hybrids, headwater...
Effects of capture and handling on survival of female northern pintails
R. R. Cox Jr., A. D. Afton
1998, Journal of Field Ornithology (69) 276-287
Identification of capture and handling procedures that influence survival of waterfowl has important research and management implications. We captured 347 female Northern Pintails (Anas acuta) using rocket nets, fitted them with harness (backpack-type) radio transmitters, and monitored their survival during the first 10 d following release. Females were 16 times...
Using safety inspection data to estimate shaking intensity for the 1994 Northridge earthquake
K. Thywissen, J. Boatwright
1998, Bulletin of the Seismological Society of America (88) 1243-1253
We map the shaking intensity suffered in Los Angeles County during the 17 January 1994, Northridge earthquake using municipal safety inspection data. The intensity is estimated from the number of buildings given red, yellow, or green tags, aggregated by census tract. Census tracts...
Reductive dissolution and reactive solute transport in a sewage-contaminated glacial outwash aquifer
R. W. Lee, P.C. Bennett
1998, Ground Water (36) 583-595
Contamination of shallow ground water by sewage effluent typically contains reduced chemical species that consume dissolved oxygen, developing either a low oxygen geochemical environment or an anaerobic geochemical environment. Based on the load of reduced chemical species discharged to shallow ground water and the amounts of reactants in the aquifer...
Dynamic stress changes during earthquake rupture
S.M. Day, G. Yu, D.J. Wald
1998, Bulletin of the Seismological Society of America (88) 512-522
We assess two competing dynamic interpretations that have been proposed for the short slip durations characteristic of kinematic earthquake models derived by inversion of earthquake waveform and geodetic data. The first interpretation would require a fault constitutive relationship in which rapid dynamic restrengthening...
The excitation and characteristic frequency of the long-period volcanic event: An approach based on an inhomogeneous autoregressive model of a linear dynamic system
M. Nakano, Hiroyuki Kumagai, M. Kumazawa, K. Yamaoka, B. A. Chouet
1998, Journal of Geophysical Research B: Solid Earth (103) 10031-10046
We present a method to quantify the source excitation function and characteristic frequencies of long-period volcanic events. The method is based on an inhomogeneous autoregressive (AR) model of a linear dynamic system, in which the excitation is assumed to be a time-localized function applied at the beginning of the event....
Evaluating landscape health: Integrating societal goals and biophysical process
D.J. Rapport, C. Gaudet, J.R. Karr, Jill Baron, C. Bohlen, W. Jackson, Bruce Jones, R.J. Naiman, B. Norton, M. M. Pollock
1998, Journal of Environmental Management (53) 1-15
Evaluating landscape change requires the integration of the social and natural sciences. The social sciences contribute to articulating societal values that govern landscape change, while the natural sciences contribute to understanding the biophysical processes that are influenced by human activity and result in ecological change. Building upon Aldo Leopold's criteria...
Flow and suspended particulate transport in a tidal bottom layer, south San Francisco Bay, California
R. T. Cheng, J. W. Gartner, D.A. Cacchione, G. B. Tate
1998, Conference Paper, Physics of estuaries and coastal seas: Proceedings of the 8th International Biennial Conference on Physics of Estuaries and Coastal Seas
Field investigations of the hydrodynamics and the resuspension and transport of particulate matter in a bottom boundary layer were carried out in South San Francisco Bay, California during March-April 1995. The GEOPROBE, an instrumented bottom tripod, and broad-band acousti Doppler current profilers were used in this investigation. The instrument assemblage...
Estimator selection for closed-population capture: recapture
Thomas R. Stanley, Kenneth P. Burnham
1998, Journal of Agricultural, Biological, and Environmental Statistics (3) 131-150
For valid statistical inference, it is important to select an appropriate statistical model. In the analysis of capture-recapture data under the closed-population models of Otis et al. (1978), information theoretic and hypothesis testing approaches to model selection are not practical, because some of the models have likelihoods with nonidenti- fiable...
A nowcast model for tides and tidal currents in San Francisco Bay, California
Ralph T. Cheng, Richard E. Smith
1998, Conference Paper
National Oceanographic and Atmospheric Administration (NOAA) installed Physical Oceanographic Real-Time System (PORTS) in San Francisco Bay, California to provide observations of tides, tidal currents, and meteorological conditions. PORTS data are used for optimizing vessel operations, increasing margin of safety for navigation, and guiding hazardous material spill prevention and response. Because...
An empirical model of the tidal currents in the Gulf of the Farallones
J.M. Steger, C. A. Collins, F.B. Schwing, M. Noble, N. Garfield, M.T. Steiner
1998, Deep-Sea Research Part II: Topical Studies in Oceanography (45) 1471-1505
Candela et al. (1990, 1992) showed that tides in an open ocean region can be resolved using velocity data from a ship-mounted ADCP. We use their method to build a spatially varying model of the tidal currents in the Gulf of the Farallones, an area of complicated bathymetry where the...
Predicting CH4 adsorption capacity of microporous carbon using N2 isotherm and a new analytical model
Jielun Sun, S. Chen, M. Rostam-Abadi, M.J. Rood
1998, ACS Division of Fuel Chemistry, Preprints (43) 596-599
A new analytical pore size distribution (PSD) model was developed to predict CH4 adsorption (storage) capacity of microporous adsorbent carbon. The model is based on a 3-D adsorption isotherm equation, derived from statistical mechanical principles. Least squares error minimization is used to solve the PSD without any pre-assumed distribution function....
Aryl hydrocarbon receptor function in early vertebrates:Inducibility of cytochrome P450 1A in agnathan and elasmobranch fish
Mark E. Hahn, Bruce R. Woodin, John J. Stegeman, Donald E. Tillitt
1998, Comparative Biochemistry and Physiology, Part C: Pharmacology, Toxicology and Endocrinology (120) 67-75
The mammalian aryl hydrocarbon receptor (AHR) is a ligand-activated transcription factor that controls the expression of cytochrome P450 1A (CYP1A) genes in response to halogenated aromatic hydrocarbons such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). The natural ligand and normal physiologic function of this protein are as yet unknown. One approach to understanding AHR...
Highly precise Re-Os dating for molybdenite using alkaline fusion and NTIMS
R. Markey, H. Stein, J. Morgan
1998, Talanta (45) 935-946
The technique described in this paper represents the modification and combination of two previously existing methods, alkaline fusion and negative thermal ion mass spectrometry (NTIMS). We have used this technique to analyze repeatedly a homogeneous molybdenite powder used as a reference standard in our laboratory. Analyses were made over a...
Caledonian eclogite-facies metamorphism of early Proterozoic protoliths from the North-East Greenland Eclogite Province
H.K. Brueckner, J. A. Gilotti, A.P. Nutman
1998, Contributions to Mineralogy and Petrology (130) 103-120
High-pressure metamorphic assemblages occur in mafic, ultramafic and a few intermediate rocks in a gneiss complex that covers an area of approximately 400 ?? 100 km in the North-East Greenland Caledonides. Detailed petrologic and geochronologic studies were carried out on three samples in order to clarify the P-T-t evolution of...
Mallard duckling growth and survival in relation to aquatic invertebrates
R. R. Cox Jr., M.A. Hanson, C.C. Roy, N.H. Euliss Jr., Douglas H. Johnson, Malcolm G. Butler
1998, Journal of Wildlife Management (62) 124-133
Identification and assessment of the relative importance of factors affecting duckling growth and survival are essential for effective management of mallards on breeding areas. For each of 3 years (1993-95), we placed F1-generation wild mallard (Anas platyrhynchos) females on experimental wetlands and allowed them to mate, nest, and rear broods...
Retention of NO3/- in an upland stream environment: A mass balance approach
Douglas A. Burns
1998, Biogeochemistry (40) 73-96
Models of the effects of atmospheric N deposition in forested watersheds have not adequately accounted for the effects of aquatic and near-stream processes on the concentrations and loads of NO3/- in surface waters. This study compared the relative effects of aquatic and near-stream processes with those from the terrestrial ecosystem...
Response of Pacific walruses to disturbances from capture and handling activities at a haul-out in Bristol Bay, Alaska
C.V. Jay, Tamara L. Olson, G.W. Garner, Brenda E. Ballachey
1998, Marine Mammal Science (14) 819-828
Observations were made on hems of the Pacific walrus (Odobenus rosmarus divergens) to study their response during the capturing and handling of adult males in summer 1995 at a haul-out at Cape Peirce in southwestern Alaska. Three behaviors (alertness, displacement, and dispersal) were quantified from 16 capture sessions. Herd sizes...
Factors controlling As and U in shallow ground water, southern Carson Desert, Nevada
A. H. Welch, M.S. Lico
1998, Applied Geochemistry (13) 521-539
Unusually high As and U concentrations (> 100 ??g/L) are widespread in shallow ground water beneath the southern Carson Desert. The high concentrations, which locally exceed 1000 ??g/L, are of concern from a human health standpoint because the shallow ground water is used for domestic supply. Possible affects on wildlife...
