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Page 1382, results 34526 - 34550

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Fat fractal scaling of drainage networks from a random spatial network model
Michael R. Karlinger, Brent M. Troutman
1992, Water Resources Research (28) 1975-1981
An alternative quantification of the scaling properties of river channel networks is explored using a spatial network model. Whereas scaling descriptions of drainage networks previously have been presented using a fractal analysis primarily of the channel lengths, we illustrate the scaling of the surface area of the channels defining the...
Solute transport with multiple equilibrium-controlled or kinetically controlled chemical reactions
John C. Friedly, Jacob Rubin
1992, Water Resources Research (28) 1935-1953
A new approach is applied to the problem of modeling solute transport accompanied by many chemical reactions. The approach, based on concepts of the concentration space and its stoichiometric subspaces, uses elements of the subspaces as primary dependent variables. It is shown that the resulting model equations are compact in...
Larval American shad: Effects of age and group size on swimming and feeding behavior
R. M. Ross, T. W. H. Backman
1992, Transactions of the American Fisheries Society (121) 508-516
We analyzed the behavior of 3–4‐d‐old prolarval and 28–33‐d‐old metalarval American shad Alosa sapidissima in groups of 3–1,000 fish per 22‐L glass tank, to determine whether (1) previously described juvenile behavior patterns first develop in larvae, (2) group size or density alters the behavior of larvae, and (3) schooling or other forms...
Annual survival rates of adult and immature eastern population tundra swans
James D. Nichols, J. Bart, Roland J. Limpert, William J.L. Sladen, James E. Hines
1992, Journal of Wildlife Management (56) 485-494
Tundra swans (Cygnus columbianus) of the eastern population were neckbanded in Maryland, North Carolina, and Alaska from 1966 through 1990. These swans were resighted and recaptured during autumn, winter, and spring, 1966-1990. Although the original motivation for this study involved swan movements, we wanted to use the resulting data to...
Microcrack interaction leading to shear fracture
David A. Lockner, Diane E. Moore, Ze’ev Reches
1992, Conference Paper, 33rd U.S. Symposium on Rock Mechanics
In this paper we draw upon recent laboratory results concerning the nucleation and growth of shear fractures in brittle rock. In homogeneous, crystalline rock such as granite, fault nucleation occurs rapidly and with only subtle changes in precursory microcrack patterns. Once nucleated, the fault grows rapidly, restricting microcrack damage to...
Reply to Dr. Stoesselfs comment on “Reaction paths and equilibrium end-points in solid-solution aqueous-solution systems”
Pierre D. Glynn, Eric J. Reardon, Niel Plummer, Eurybiades Busenberg
1992, Geochimica et Cosmochimica Acta (56) 2559-2572
In reply to the Critical Comment of R. K. Stoessell (this issue), limiting activity coefficients of bromide in halite (γNaBr) have been calculated by least-squares fitting of Simons et al.'s (1952) bromide distribution coefficient data for the Na(Cl,Br)-NaOH-H2O system at 35°C. Regular and subregular solidsolution model fits give γNaBr...
Seismicity and geometry of a 110‐km‐long blind thrust fault 1. The 1985 Kettleman Hills, California, earthquake
E. Ekstrand, Ross Stein, J. P. Eaton, D. Eberhart-Phillips
1992, Journal of Geophysical Research B: Solid Earth (97) 4843-4864
The August 4, 1985, Kettleman Hills earthquake was the third in a sequence of moderate shocks to occur beneath the northern half of a 110‐km‐long fold chain bounding the eastern California Coast Ranges. The 1982 MW =5.4 New Idria, 1983 MW=6.5 Coalinga, and 1985 MW=6.1 Kettleman Hills events define a southward...
Upper-mantle seismic discontinuities and the thermal structure of subduction zones
J.E. Vidale, H.M. Benz
1992, Nature (356) 678-683
The precise depths at which seismic velocities change abruptly in the upper mantle are revealed by the analysis of data from hundreds of seismometers across the western United States. The boundary near 410km depth is locally elevated, that near 660 km depressed. The depths of these boundaries, which mark phase...
Revised budget for the oceanic uptake of anthropogenic carbon dioxide
J.L. Sarmiento, E.T. Sundquist
1992, Nature (356) 589-593
Tracer-calibrated models of the total uptake of anthropogenic CO2 by the world's oceans give estimates of about 2 gigatonnes carbon per year1, significantly larger than a recent estimate2 of 0.3-0.8 Gt C yr-1 for the synoptic air-to-sea CO2 influx. Although both estimates require that the global CO2 budget must be balanced by a large unknown...
A model for the generation of two-dimensional surf beat
Jeffrey H. List
1992, Journal of Geophysical Research C: Oceans (97) 5623-5635
A finite difference model predicting group-forced long waves in the nearshore is constructed with two interacting parts: an incident wave model providing time-varying radiation stress gradients across the nearshore, and a long-wave model which solves the equations of motion for the forcing imposed by the incident waves. Both shallow water...
Application of continuum models to deformation of the Aleutian Island Arc
Eric L. Geist, David W. Scholl
1992, Journal of Geophysical Research Solid Earth (97) 4953-4967
Continuum models were constructed to describe large‐scale deformation of the Aleutian Island Arc over the past 5 m.y. These models consider the island arc as a continuum in the horizontal plane with the velocity boundary condition at the Pacific edge stated as a fraction of Pacific plate convergence transferred to...
Limitations of quantitative analysis of deep crustal seismic reflection data: Examples from GLIMPCE
Myung W. Lee, Deborah R. Hutchinson
1992, Journal of Geophysical Research B: Solid Earth (97) 4705-4719
Amplitude preservation in seismic reflection data can be obtained by a relative true amplitude (RTA) processing technique in which the relative strength of reflection amplitudes is preserved vertically as well as horizontally, after compensating for amplitude distortion by near-surface effects and propagation effects. Quantitative analysis of relative true amplitudes of...
On the characteristics of local geology and their influence on ground motions generated by the Loma Prieta earthquake in the San Francisco Bay region, California
Roger D. Borcherdt, Gary Glassmoyer
1992, Bulletin of the Seismological Society of America (82) 603-641
Strong ground motions recorded at 34 sites in the San Francisco Bay region from the Loma Prieta earthquake show marked variations in characteristics dependent on crustal structure and local geological conditions. Peak horizontal acceleration and velocity inferred for sites underlain by “rock” generally occur on the transverse component of motion....
Shear stress and bed roughness estimates for combined wave and current flows over a rippled bed
D.E. Drake, D.A. Cacchione, W.D. Grant
1992, Journal of Geophysical Research C: Oceans (97) 2319-2326
High‐quality bottom boundary layer measurements and bottom photographs were obtained over a sand substrate during a 10‐day deployment of the GEOPROBE tripod at an inner shelf (35‐m water depth) location off northern California. The seafloor surrounding the tripod was composed of well‐sorted medium‐grained (mean diameter, 0.25 mm) sand which was...
Gravity-driven groundwater flow and slope failure potential: 2. Effects of slope morphology, material properties, and hydraulic heterogeneity
Mark E. Reid, Richard M. Iverson
1992, Water Resources Research (28) 939-950
Hillslope morphology, material properties, and hydraulic heterogeneities influence the role of groundwater flow in provoking slope instability. We evaluate these influences quantitatively by employing the elastic effective stress model and Coulomb failure potential concept described in our companion paper (Iverson and Reid, this issue). Sensitivity analyses show that of four...
Gravity-driven groundwater flow and slope failure potential: 1. Elastic effective-stress model
Richard M. Iverson, Mark E. Reid
1992, Water Resources Research (28) 925-938
Hilly or mountainous topography influences gravity-driven groundwater flow and the consequent distribution of effective stress in shallow subsurface environments. Effective stress, in turn, influences the potential for slope failure. To evaluate these influences, we formulate a two-dimensional, steady state, poroelastic model. The governing equations incorporate groundwater effects as body forces,...
Performance of nine external tags on hatchery-reared rainbow trout
K.W. McAllister, P. E. McAllister, R.C. Simon, J.K. Werner
1992, Transactions of the American Fisheries Society (121) 192-198
We evaluated nine commercially available tags to determine their suitability for marking yearling rainbow trout Oncorhynchus mykiss reared in raceways and circular tanks. The tags tested were Floy vinyl tubing tags FD‐67 anchor, FT‐2 dart, FT‐4 cinch‐up, and FT‐4 lock‐on; modified Carlin; modified Petersen disk; Monel strap 4‐1005; Monel butt end 4‐1242;...
Thin, low‐velocity crust beneath the southern Yukon‐Tanana Terrane, east central Alaska: Results from Trans‐Alaska crustal transect refraction/wide‐angle reflection data
Bruce C. Beaudoin, Gary S. Fuis, Walter D. Mooney, Warren J. Nokleberg, Nikolas I. Christensen
1992, Journal of Geophysical Research B: Solid Earth (97) 1921-1942
A seismic refraction/wide‐angle reflection survey for the Trans‐Alaska Crustal Transect program reveals a thin, reflective crust beneath the southern Yukon‐Tanana terrane (YTT) in east central Alaska. These data are the first detailed refraction survey of the southern YTT and compose a 130‐km‐long reversed profile along the Alaska...
Estimating transition probabilities for stage-based population projection matrices using capture-recapture data
James D. Nichols, John R. Sauer, Kenneth H. Pollock, Jay B. Hestbeck
1992, Ecology (73) 306-312
In stage—based demography, animals are often categorized into size (or mass) classes, and size—based probabilities of surviving and changing mass classes must be estimated before demographic analyses can be conducted. In this paper, we develop two procedures for the estimation of mass transition probabilities from capture—recapture data. The first approach...
Petrology of the Caribou Mountain Pluton, Klamath Mountains, California
Calvin G. Barnes, Melanie Barnes, Ronald W. Kistler
1992, Journal of Petrology (33) 95-124
The Caribou Mountain pluton is a small trondhjemitic body that intruded semipelitic schist of the Stuart Fork terrane in late Middle Jurassic to Early Cretaceous time. Its emplacement followed the intrusion of an adjoining body of hornblende quartz diorite called the Middle Fork pluton and the mode of its...
Acoustic waveform logging: Advances in theory and application
F.L. Paillet, C.H. Cheng, W.D. Pennington
1992, Log Analyst (33) 239-258
Full-waveform acoustic logging has made significant advances in both theory and application in recent years, and these advances have greatly increased the capability of log analysts to measure the physical properties of formations. Advances in theory provide the analytical tools required to understand the properties of measured seismic waves, and...
Evidence for cenozoic crustal extension in the Bering Sea region
Alan K. Cooper, M. S. Marlow, D.W. Scholl, A.J. Stevenson
1992, Tectonics (11) 719-731
Geophysical and regional geologic data provide evidence that parts of the oceanic crust in the abyssal basins of the Bering Sea have been created or altered by crustal extension and back‐arc spreading. These processes have occurred during and since early Eocene time when the Aleutian Ridge developed and isolated oceanic...