Flow to a well of finite diameter in a homogeneous, anisotropic water table aquifer
Allen F. Moench
1997, Water Resources Research (33) 1397-1407
A Laplace transform solution is presented for the problem of flow to a partially penetrating well of finite diameter in a slightly compressible water table aquifer. The solution, which allows for evaluation of both pumped well and observation piezometer data, accounts for effects of well bore storage and skin and...
The modern atmospheric background dust load: Recognition in Central Asian snowpack, and compositional constraints
T. Hinkley, F. Pertsiger, L. Zavjalova
1997, Geophysical Research Letters (24) 1607-1610
Dusts in strata of snowpack in the Alai-Pamir range, Kirghizstan, Central Asia, have chemical compositions that are in the same restricted range as those of the dusts found in snowpacks at three other locations: central south Greenland, the St. Elias range (Alaska), and coastal Antarctica, where...
Impact of an extreme event on the sediment budget: Hurricane Andrew in the Louisiana barrier islands
Jeffrey H. List, Mark E. Hansen, Sallenger Jr., Bruce E. Jaffe
B.L Edge, editor(s)
1997, Conference Paper, Proceedings of the Coastal Engineering Conference
This paper examines the influence of Hurricane Andrew on the sediment budget of an 80-kilometer section of the Louisiana barrier islands west of the modern Mississippi delta. Because long-term bathymetric change has been extensively studied in this area, excellent baseline data are available for evaluating the impact of Hurricane Andrew....
Eustatic and tectonic control of deposition of the lower and middle Pennsylvanian strata of the Central Appalachian Basin
D.R. Chesnut Jr.
1997, Prace - Panstwowego Instytutu Geologicznego 39-41
Stratigraphic analysis of Lower and Middle Pennsylvanian rocks of part of the Central Appalachian Basin reveals two orders of cycles and one overall trend in the vertical sequence of coal-bearing rocks. The smallest order cycle, the coal-clastic cycle, begins at the top of a major-resource coal bed and is composed...
Crustal structure, evolution, and volcanic unrest of the Alban Hills, Central Italy
C. Chiarabba, A. Amato, P.T. Delaney
1997, Bulletin of Volcanology (59) 161-170
The Alban Hills, a Quaternary volcanic center lying west of the central Apennines, 15-25 km southeast of Rome, last erupted 19ka and has produced approximately 290 km3 of eruptive deposits since the inception of volcanism at 580 ka. Earthquakes of moderate intensity have been generated there at least since the...
Field-scale tests for determining mixing patterns associated with coarse-bubble air diffuser configurations, Egan Quarry, Illinois
Nancy J. Hornewer, G.P. Johnson, Dale M. Robertson, Miki Hondzo
1997, Conference Paper, Proceedings, Congress of the International Association of Hydraulic Research, IAHR
The U.S. Geological Survey in cooperation with the U.S. Army Corps of Engineers, Chicago District did field-scale tests in August-September 1996 to determine mixing patterns associated with different configurations of coarse-bubble air diffusers. The tests were done in an approximately 13-meter deep quarry near Chicago, Ill. Three-dimensional velocity, water-temperature, dissolved...
A three component model to estimate sensible heat flux over sparse shrubs in Nevada
A. Chehbouni, W. D. Nichols, E.G. Njoku, J. Qi, Y.H. Kerr, F. Cabot
1997, Remote Sensing Reviews (15) 99-112
It is now recognized that accurate partitioning of available energy into sensible and latent heat flux is crucial to understanding surface‐atmosphere interactions. This issue is more complicated in arid and semi‐arid regions where the relative contribution to surface fluxes from the soil and vegetation may vary significantly throughout the day...
Rapid and widespread dispersal of flood sediment on the northern California margin
R. A. Wheatcroft, C.K. Sommerfield, D.E. Drake, J. C. Borgeld, C.A. Nittrouer
1997, Geology (25) 163-166
The dispersal of flood sediment from small river systems is a poorly studied, yet potentially important aspect of active continental-margin sedimentation. In January 1995, during a flood with a 30 yr return period, the Eel River (northern California) delivered an estimated 25 ±...
Sr isotope evidence for a lacustrine origin for the upper Miocene to Pliocene Bouse Formation, lower Colorado River trough, and implications for timing of Colorado Plateau uplift
J.E. Spencer, P. J. Patchett
1997, Geological Society of America Bulletin (109) 767-778
The upper Miocene to Pliocene Bouse Formation in the lower Colorado River trough, which consists largely of siltstone with basal tufa and marl, has been interpreted as estuarine on the basis of paleontology. This interpretation requires abrupt marine inundation that has been linked...
A mechanism for high wall-rock velocities in rockbursts
Art McGarr
1997, Pure and Applied Geophysics (150) 381-391
Considerable evidence has been reported for wall-rock velocities during rockbursts in deep gold mines that are substantially greater than ground velocities associated with the primary seismic events. Whereas varied evidence suggests that slip across a fault at the source of an event generates nearby particle velocities of, at most, several...
A physically-based method for predicting peak discharge of floods caused by failure of natural and constructed earthen dams
J. S. Walder
1997, IAHS-AISH Publication 217-224
We analyse a simple, physically-based model of breach formation in natural and constructed earthen dams to elucidate the principal factors controlling the flood hydrograph at the breach. Formation of the breach, which is assumed trapezoidal in cross-section, is parameterized by the mean rate of downcutting, k, the value of which...
Some thoughts on problems associated with various sampling media used for environmental monitoring
A. J. Horowitz
1997, Conference Paper, Analyst
Modern analytical instrumentation is capable of measuring a variety of trace elements at concentrations down into the single or double digit parts-per-trillion (ng l-1) range. This holds for the three most common sample media currently used in environmental monitoring programs: filtered water, whole-water and separated suspended sediment. Unfortunately, current analytical...
Organic carbon balance and net ecosystem metabolism in Chesapeake Bay
W. M. Kemp, E.M. Smith, M. Marvin-DiPasquale, W.R. Boynton
1997, Marine Ecology Progress Series (150) 229-248
The major fluxes of organic carbon associated with physical transport and biological metabolism were compiled, analyzed and compared for the mainstem portion of Chesapeake Bay (USA). In addition, 5 independent methods were used to calculate the annual mean net ecosystem metabolism (NEM = production - respiration) for the integrated Bay....
A GIS model to predict black bear habitat use
F.T. Van Manen, M.R. Pelton
1997, Journal of Forestry (95) 6-12
No abstract available....
Bulk-friction modeling of afterslip and the modified Omori law
Leif Wennerberg, Robert V. Sharp
1997, Tectonophysics (277) 109-136
Afterslip data from the Superstition Hills fault in southern California, a creep event on the same fault, the modified Omori law, and cumulative moments from aftershocks of the 1957 Aleutian Islands earthquake all indicate that the original formulation by Dieterich (1981) [Constitutive properties of faults with simulated gouge. AGU, Geophys....
Prevention of fin erosion rainbow trout, Onchorynchus mykiss, by dietary modification
F.T. Barrows, W.A. Lellis
1997, Bozeman Information Leaflet 86
No abstract available at this time...
Analysis of the Cape Cod tracer data
Souheil Ezzedine, Yoram Rubin
1997, Water Resources Research (33) 1-11
An analysis of the Cape Cod test was performed using several first- and higher-order theoretical models. We compare conditional and unconditional solutions of the transport equation and employ them for analysis of the experimental data. We consider spatial moments, mass breakthrough curves, and the distribution of the solute mass in...
Energy sources and ecological role of crayfishes in an Ozark stream: Insights from stable isotopes and gut analysis
G.W. Whitledge, C.F. Rabeni
1997, Canadian Journal of Fisheries and Aquatic Sciences (54) 2555-2563
Energy sources for the crayfishes Orconectes luteus and O. punctimanus in the Jacks Fork River, Missouri, were quantified using stable isotopes (??13C and ??15N) and gut-content analysis. A dual-isotope mixing model indicated that about two thirds of crayfish production originated from allochthonous carbon sources, and 30-50% of crayfish production was...
Sedimentary phosphorus cycling and a phosphorus mass balance for the Green Bay (Lake Michigan) ecosystem
Klump J. Val, D.N. Edgington, P.E. Sager, Dale M. Robertson
1997, Canadian Journal of Fisheries and Aquatic Sciences (54) 10-26
The tributaries of Green Bay have long been recognized as major sources of phosphorus in the Lake Michigan basin. The status of Green Bay as a sink or source of phosphorus for Lake Michigan proper has been less well defined. The bay receives nearly 70% of its annual load of...
Microorganisms as tracers in groundwater injection and recovery experiments: A review
R.W. Harvey
1997, FEMS Microbiology Reviews (20) 461-472
Modern day injection and recovery techniques designed to examine the transport behavior of microorganisms in groundwater have evolved from experiments conducted in the late 1800s, in which bacteria that form red or yellow pigments were used to trace flow paths through karst and fractured- rock aquifers. A number of subsequent...
Use of chemical and isotopic tracers to characterize the interactions between ground water and surface water in mantled karst
B. G. Katz, T.B. Coplen, T.D. Bullen, J. Hal Davis
1997, Ground Water (35) 1014-1028
In the mantled karst terrane of northern Florida, the water quality of the Upper Floridan aquifer is influenced by the degree of connectivity between the aquifer and the surface. Chemical and isotopic analyses [18O/16O (δ18O), 2H/1H (δD), 13C/12C (δ13C), tritium (3H), and strontium‐87/strontium‐86 (87Sr/86Sr)] along with geochemical mass‐balance modeling were used to...
Potential effects of climate change on freshwater ecosystems of the New England/Mid-Atlantic Region
M.V. Moore, M. L. Pace, J.R. Mather, Peter S. Murdoch, R. W. Howarth, C.L. Folt, C.-Y. Chen, Harold F. Hemond, P.A. Flebbe, C. T. Driscoll
1997, Hydrological Processes (11) 925-947
Numerous freshwater ecosystems, dense concentrations of humans along the eastern seaboard, extensive forests and a history of intensive land use distinguish the New England/Mid-Atlantic Region. Human population densities are forecast to increase in portions of the region at the same time that climate is expected to be changing. Consequently, the...
Potential effects of climate change on aquatic ecosystems of the Great Plains of North America
A.P. Covich, S.C. Fritz, P.J. Lamb, R.D. Marzolf, W.J. Matthews, K.A. Poiani, E.E. Prepas, M.B. Richman, T. C. Winter
1997, Hydrological Processes (11) 993-1021
The Great Plains landscape is less topographically complex than most other regions within North America, but diverse aquatic ecosystems, such as playas, pothole lakes, ox-bow lakes, springs, groundwater aquifers, intermittent and ephemeral streams, as well as large rivers and wetlands, are highly dynamic and responsive to extreme climatic fluctuations. We...
Characterisation of physical environmental factors on an intertidal sandflat, Manukau Harbour, New Zealand
R.G. Bell, T.M. Hume, T.J. Dolphin, M.O. Green, R. A. Walters
1997, Conference Paper, Journal of Experimental Marine Biology and Ecology
Physical environmental factors, including sediment characteristics, inundation time, tidal currents and wind waves, likely to influence the structure of the benthic community at meso-scales (1-100 m) were characterised for a sandflat off Wiroa Island (Manukau Harbour, New Zealand). In a 500 x 250 m study site, sediment characteristics and bed...
An 18 million year record of vegetation and climate change in northwestern Canada and Alaska: Tectonic and global climatic correlates
J. M. White, T. A. Ager, D.P. Adam, E. B. Leopold, Gaisheng Liu, H. Jette, C. E. Schweger
1997, Palaeogeography, Palaeoclimatology, Palaeoecology (130) 293-306
We reconstruct long-term vegetation/paleoclimatic trends, spanning the last 18 million years, in Alaska. Yukon and far western Northwest Territories. Twenty-one average percentage spectra for pollen and spores are assembled from eight surface/subsurface sections. The sections are dated independently or by correlation. Pollen and spore ratios indicate the direction of change...
