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Full-Text Articles in Physical Sciences and Mathematics

Factors Affecting The Movements Of Rainbow Trout (Oncorhynchus Mykiss) In Lake Ogallala, Nebraska, Tadd M. Barrow Dec 1998

Factors Affecting The Movements Of Rainbow Trout (Oncorhynchus Mykiss) In Lake Ogallala, Nebraska, Tadd M. Barrow

School of Natural Resources: Dissertations, Theses, and Student Research

No abstract provided.


Comment On "Beach Water Table Fluctuations Due To Wave Run-Up: Capillarity Effects" By L. Li Et Al., Vitaly A. Zlotnik Nov 1998

Comment On "Beach Water Table Fluctuations Due To Wave Run-Up: Capillarity Effects" By L. Li Et Al., Vitaly A. Zlotnik

Department of Earth and Atmospheric Sciences: Faculty Publications

Vitaly A. Zlotnik's comment on "Beach water table fluctuations due to wave run-up: Capillarity effects" by L. Li, D. A. Barry, J.-Y. Parlange, and C. B. Pattiaratchi, published in Water Resources Research (1997) 3(5): 935-945.


Antelope County Test-Hole Logs: Nebraska Water Survey Test-Hole Report No. 2, Sue Olafsen Lackey, Frank A. Smith, Robert F. Diffendal Jr. Oct 1998

Antelope County Test-Hole Logs: Nebraska Water Survey Test-Hole Report No. 2, Sue Olafsen Lackey, Frank A. Smith, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

In 1930, the Conservation and Survey Division of the University of Nebraska and the United States Geological Survey began a program of cooperative groundwater studies in Nebraska. Since then test drilling by use of rotary drilling equipment has been an integral part of that program. This report contains logs of all the test holes drilled in the county under the program as well as those drilled by the Conservation and Survey Division with financial assistance from other government agencies.

The map in this report shows the location of all test holes drilled in the county since 1930.

Present techniques of …


Mountain Evolution And Environmental Changes Of Huangshan, China, P.-H. Huang, Robert F. Diffendal Jr., M. Yang, Patricia E. Helland Oct 1998

Mountain Evolution And Environmental Changes Of Huangshan, China, P.-H. Huang, Robert F. Diffendal Jr., M. Yang, Patricia E. Helland

Department of Earth and Atmospheric Sciences: Faculty Publications

Huangshan (Yellow Mountain) is located in southern part of the lower reaches of the Yangtze River. The highest Lotus Flower peak is 1,864 m above sea level. Formative ages of the Huangshan and its granite, process of mountain geomorphic evolution from the Eocene to Quaternary, environmental changes of Quaternary, formative origin of beautiful peaks and fascinating rocks were studied and questionable "Pleistocene glaciation" was also discussed in this paper.


Holt County Test-Hole Logs: Nebraska Water Survey Test-Hole Report No. 45, Sue Olafsen Lackey, Frank A. Smith, Robert F. Diffendal Jr. Sep 1998

Holt County Test-Hole Logs: Nebraska Water Survey Test-Hole Report No. 45, Sue Olafsen Lackey, Frank A. Smith, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

In 1930, the Conservation and Survey Division of the University of Nebraska and the United States Geological Survey began a program of cooperative groundwater studies in Nebraska. Since then test drilling by use of rotary drilling equipment has been an integral part of that program. This report contains logs of all the test holes drilled in Holt County, Nebraska, under the program as well as those drilled by the Conservation and Survey Division with financial assistance from other government agencies.

The map in this report shows the location of all test holes drilled in Holt County, Nebraska from 1944 to …


Climate Change And Nebraska Sep 1998

Climate Change And Nebraska

United States Environmental Protection Agency: Staff Publications

The earth's climate is predicted to change because human activities are altering the chemical composition of the atmosphere through the buildup of greenhouse gases - primarily carbon dioxide, methane, nitrous oxide, and chlorofluorocarbons. The heat-trapping property of these greenhouse gases is undisputed. Although there is uncertainty about exactly how and when the earth's climate will respond to enhanced concentrations of greenhouse gases, observations indicate that detectable changes are under way. There most likely will be increases in temperature and changes in precipitation, soil moisture, and sea level, which could have adverse effects on many ecological systems, as well as on …


Birds And Agroecological Relationships In Organic And Non-Organic Farmland, Nancy A. Beecher Aug 1998

Birds And Agroecological Relationships In Organic And Non-Organic Farmland, Nancy A. Beecher

School of Natural Resources: Dissertations, Theses, and Student Research

No abstract provided.


Magnitude And Significance Of Carbon Burial In Lakes, Reservoirs, And Peatlands, Walter E. Dean, Eville Gorham Jun 1998

Magnitude And Significance Of Carbon Burial In Lakes, Reservoirs, And Peatlands, Walter E. Dean, Eville Gorham

United States Geological Survey: Staff Publications

Globally, lakes are currently accumulating organic carbon (OC) at an estimated annual rate of about 42 Tg•yr-1. Most of the OC in all but the most oligotrophic of these lakes is autochthonous, produced by primary production in the lakes. The sediments of reservoirs accumulate an additional 160 Tg annually, and peatlands contribute 96 Tg annually. These three carbon pools collectively cover less than 2% of the Earth’s surface and constitute a carbon sink of about 300 Tg•yr-1. Although the oceans cover 71% of the Earth’s surface, they accumulate OC at a rate of only about 100 …


Landowner And Tourist Attitudes Toward Elk Management In The Pine Ridge Region Of Northwestern Nebraska, R. Daniel Crank May 1998

Landowner And Tourist Attitudes Toward Elk Management In The Pine Ridge Region Of Northwestern Nebraska, R. Daniel Crank

School of Natural Resources: Dissertations, Theses, and Student Research

No abstract provided.


Influence Of Buffer Strip Width And Composition In Reduction Of Agricultural Non-Point Source Contaminants, Tim Schmitt May 1998

Influence Of Buffer Strip Width And Composition In Reduction Of Agricultural Non-Point Source Contaminants, Tim Schmitt

School of Natural Resources: Dissertations, Theses, and Student Research

No abstract provided.


An Atlas Of The Sand Hills, Ann S. Bleed, Charles A. Flowerday May 1998

An Atlas Of The Sand Hills, Ann S. Bleed, Charles A. Flowerday

Conservation and Survey Division

The Sand Hills region, approximately 19,300 square miles of sand dunes stretching 265 miles across Nebraska and into South Dakota, is the largest sand-dune area in the Western Hemisphere and is one of the largest grass-stabilized dune regions in the world.


Paleocene Mammalian Biostratigraphy Of The Carbon Basin, Southeastern Wyoming, And Age Constraints On Local Phases Of Tectonism, Ross Secord May 1998

Paleocene Mammalian Biostratigraphy Of The Carbon Basin, Southeastern Wyoming, And Age Constraints On Local Phases Of Tectonism, Ross Secord

Department of Earth and Atmospheric Sciences: Faculty Publications

Mammalian fossils from two principal collecting areas in the lower Hanna Formation of the Carbon Basin comprise three faunas, the Grayson Ridge, Halfway Hill, and Sand Creek faunas. The Grayson Ridge and Halfway Hill faunas are diverse, consisting cumulatively of 29 mammalian species, at least two of which are new. The faunas are approximately equivalent in age and are either latest Torrejonian or earliest Tiffanian, or possibly sample both NALMAs. In any event, the faunas are very close in age to the lbrrejonian-Tiffanian boundary. Strata bearing the Grayson Ridge and Halfway Hill faunas were truncated by erosion, resulting in a …


A Diatom-Based Reconstruction Of Drought Intensity, Duration, And Frequency From Moon Lake, North Dakota: A Sub-Decadal Record Of The Last 2,300 Years, Kathleen R. Laird, Sherilyn C. Fritz, Brian F. Cumming Apr 1998

A Diatom-Based Reconstruction Of Drought Intensity, Duration, And Frequency From Moon Lake, North Dakota: A Sub-Decadal Record Of The Last 2,300 Years, Kathleen R. Laird, Sherilyn C. Fritz, Brian F. Cumming

Department of Earth and Atmospheric Sciences: Faculty Publications

Diatom assemblages preserved in sediment cores from closed-basin lakes can provide high-resolution records of past hydrologic and climatic conditions, including long-term patterns in the intensity, duration, and frequency of droughts. At Moon Lake, a closed-basin lake in eastern North Dakota, a comparison of diatom-inferred salinity and the precipitation-based Bhalme-Mooley Drought Index (BMDI) over the last 100 years was highly significant, suggesting that the diatom record contains a sensitive archive of past climatic conditions. A sub-decadal record of inferred salinity for the past 2300 years indicates that extreme droughts of greater intensity than those during the 1930s “Dust Bowl” were more …


How To Reduce Drought Risk, Cody Knutson, Mike Hayes, Tom Phillips Mar 1998

How To Reduce Drought Risk, Cody Knutson, Mike Hayes, Tom Phillips

Drought Mitigation Center: Faculty Publications

This guide describes a practical step-by-step process for identifying actions that can be taken to reduce potential drought-related impacts before a drought occurs. Step 1 begins with making sure that the right people are brought together and supplied with adequate data to make informed and equitable decisions during the process. Steps 2 and 3 narrow the focus of the study by identifying high priority drought-related impacts that are relevant to the user’s location or activity. Step 4 demonstrates that in order to reduce the potential for the identified impacts to occur in the future, it is necessary to understand the …


Cadmium Malonate Complexation In Aqueous Sodium Trifluoromethanesulfonate Media To 75°C; Including Dissociation Quotients Of Malonic Acid, Moira K. Ridley, Donald A. Palmer, David J. Wesolowski, Richard Kettler Jan 1998

Cadmium Malonate Complexation In Aqueous Sodium Trifluoromethanesulfonate Media To 75°C; Including Dissociation Quotients Of Malonic Acid, Moira K. Ridley, Donald A. Palmer, David J. Wesolowski, Richard Kettler

Department of Earth and Atmospheric Sciences: Faculty Publications

The molal formation quotients for cadmium-malonate complexes were measured potentiometrically from 5 to 75°C, at ionic strengths of 0.1, 0.3, 0.6 and 1.0 molal in aqueous sodium trifluoromethanesulfonate (NaTf) media. In addition, the stepwise dissociation quotients for malomc acid were measured in the same medium from 5 to 100°C, at ionic strengths of 0.1, 0.3, 0.6, and 1.0 molal by the same method. The dissociation quotients for malonic acid were modeled as a function of temperature and ionic strength with empirical equations formulated such that the equilibrium constants at infinite dilution were consistent, within the error estimates, with the malonic …


Upper Cenozoic Calcareous Nannofossil Biostratigraphy Côte D'Ivoire-Ghana Margin, Eastern Equatorial Atlantic, Samir Shafik, David K. Watkins, Im Chul Shin Jan 1998

Upper Cenozoic Calcareous Nannofossil Biostratigraphy Côte D'Ivoire-Ghana Margin, Eastern Equatorial Atlantic, Samir Shafik, David K. Watkins, Im Chul Shin

Department of Earth and Atmospheric Sciences: Faculty Publications

The distribution of calcareous nannofossils in the upper Cenozoic sections sampled at four sites in the eastern equatorial Atlantic Ocean during Ocean Drilling Program (ODP) Leg 159 is documented here. A virtually complete upper Cenozoic sequence of nannofossil (sub)zones is identified at Site 959 on the shoulder of the Côte d’Ivoire-Ghana marginal ridge, with proxies for the rare marker species being employed. Hiatuses within the middle and upper Miocene are detected at two other sites on the same ridge, being more clearly defined at Site 960 on the crest of the ridge. Two of these hiatuses are of regional significance. …


Mesozoic Biostratigraphic, Paleoenvironmental, And Paleobiogeographic Synthesis, Equatorial Atlantic, M. Moullade, David K. Watkins, F. E. Oboh-Ikuenobe, J.-P. Bellier, E. Masure, A. E.L. Holbourn, J. Erbacher, W. Kuhnt, T. Pletsch, M. A. Kaminski, R. Rauscher, S. Shafik, O. Yepes, J. Dejax, J. M. Gregg, Im Chul Shin, M. Schuler Jan 1998

Mesozoic Biostratigraphic, Paleoenvironmental, And Paleobiogeographic Synthesis, Equatorial Atlantic, M. Moullade, David K. Watkins, F. E. Oboh-Ikuenobe, J.-P. Bellier, E. Masure, A. E.L. Holbourn, J. Erbacher, W. Kuhnt, T. Pletsch, M. A. Kaminski, R. Rauscher, S. Shafik, O. Yepes, J. Dejax, J. M. Gregg, Im Chul Shin, M. Schuler

Department of Earth and Atmospheric Sciences: Faculty Publications

Cretaceous sediments from Ocean Drilling Program Leg 159 on the Côte d’Ivoire-Ghana Marginal Ridge (CIGMR), eastern equatorial Atlantic, are characterized by distinct stratigraphic changes in sedimentary facies associated with changes in the composition of the clayey and organic fractions, as well as of the calcareous nannofossil, radiolarian, foraminiferal, and palynomorph assemblages. In the absence of reliable magnetostratigraphic information, an integrated biostratigraphy provides the only means used to calibrate the geologic history of the Leg 159 area.

The existence of marine depositional environments as early as the late Aptian to early Albian close to the Leg 159 drill sites puts constraints …


Oligocene To Early Miocene Silicoflagellates From The Ivorian Basin, Eastern Equatorial Atlantic, Site 959, Maija E. Schellpeper, David K. Watkins Jan 1998

Oligocene To Early Miocene Silicoflagellates From The Ivorian Basin, Eastern Equatorial Atlantic, Site 959, Maija E. Schellpeper, David K. Watkins

Department of Earth and Atmospheric Sciences: Faculty Publications

Silicoflagellate biostratigraphy and relative abundance were determined for Site 959 in the eastern equatorial Atlantic. Five silicoflagellate zones, Corbisema apiculata, Naviculopsis biapiculata, Naviculopsis lata, Naviculopsis ponticula, and Corbisema triacantha Zones, were used with the Distephanus speculum hemisphaericus Subzone occurring in the N. biapiculata Zone. The Naviculopsis quadrata Zone is missing between the N. ponticula and N. lata Zones, indicating a hiatus in the lower Miocene cores that corresponds to hiatus NH1. Silicoflagellate relative abundance was graphed as a measure of paleoproductivity for Hole 959A. One large pulse of productivity occurred in the latest early Miocene, right before silica deposition …


7. Thermal Diagenesis Of Cretaceous Sediment Recovered At The Cote D’Ivoire – Ghana Transform Margin, Mary Anne Holmes Jan 1998

7. Thermal Diagenesis Of Cretaceous Sediment Recovered At The Cote D’Ivoire – Ghana Transform Margin, Mary Anne Holmes

Department of Earth and Atmospheric Sciences: Faculty Publications

The early opening of the South Atlantic ocean along the eastern Romanche Fracture Zone, including an initial phase of transform faulting and pull-apart basin formation, followed by the generation of a seafloor spreading center, was investigated during Ocean Drilling Program Leg 159 to the Côte d’Ivoire-Ghana continental margin. Clay minerals in the <0.5-μm fraction of tectonically disturbed sediment recovered during this leg were analyzed by X-ray diffraction to determine the extent of thermal diagenesis caused by the passing of the South Atlantic spreading center along this transform margin, and to date the passing. Results from Sites 959-961 reveal mild thermal alteration of clays, to paleotemperatures of 120°–170°C, in older, mostly undated sediment, in response to an elevated paleogeothermal gradient, as indicated by the absence of randomly interstratified illite/smectite group clays (R = 0 I/S clay), and the presence of dominant regularly interstratified (R = 1) I/S clay. Thermally altered sediment at these sites underlie unaltered sediment with likely erosional contacts. Based on a date of nannofossil biozone CC9b for the oldest unaltered sediment at Site 959, the thermal event there must have been pre-CC9b.
At Site 962, drilled on a minor marginal ridge to the west of Sites 959–961, heat has altered clay in basal sediment to R = 1 I/S, and the transition uphole to thermally unaltered sediment, bearing R = 0 I/S clay, was recovered over a 175-m-thick interval, indicating …


4. Grain-Size Distribution And Significance Of Clay And Clay-Sized Minerals In Eocene To Holocene Sediments From Sites 918 And 919 In The Irminger Basin, Kraig Heiden, Mary Anne Holmes Jan 1998

4. Grain-Size Distribution And Significance Of Clay And Clay-Sized Minerals In Eocene To Holocene Sediments From Sites 918 And 919 In The Irminger Basin, Kraig Heiden, Mary Anne Holmes

Department of Earth and Atmospheric Sciences: Faculty Publications

Published by the Ocean Drilling Program, Texas A & M University, in cooperation with the National Science Foundation and Joint Oceanographic Institutions, Inc."


Chapter 2 Climate, Donald A. Wilhite, Kenneth G. Hubbard Jan 1998

Chapter 2 Climate, Donald A. Wilhite, Kenneth G. Hubbard

Drought Mitigation Center: Faculty Publications

The broad climatic patterns of the Sand Hills region are also characteristic of the central Great Plains environment. The spatial and temporal patterns of these climatic variables have a significant effect on the natural resources of the region.


Calcareous Nannofossils From The Cretaceous Of The Deep Ivorian Basin, David K. Watkins, Samir Shafik, Im Chul Shin Jan 1998

Calcareous Nannofossils From The Cretaceous Of The Deep Ivorian Basin, David K. Watkins, Samir Shafik, Im Chul Shin

Department of Earth and Atmospheric Sciences: Faculty Publications

Micropaleontological investigation of four sites drilled by Ocean Drilling Program Leg 159 on the Côte d’Ivoire-Ghana Margin indicates that the initial invasion of oceanic surface waters into the Deep Ivorian Basin, as indicated by the presence of calcareous nannofossils, occurred during the late Albian. The nature of these assemblages suggests that these first Cretaceous oceanic surface waters were warm and relatively high in nutrients. These upper Albian sediments were deposited prior to significant tectonism at some of the sites, as indicated by their structurally deformed nature. The likely age of this tectonism is Cenomanian. The Upper Cretaceous consists of condensed …


Observation Of The Seismic Nucleation Phase In The Ridgecrest, California, Earthquake Sequence, William L. Ellsworth, Gregory C. Beroza Jan 1998

Observation Of The Seismic Nucleation Phase In The Ridgecrest, California, Earthquake Sequence, William L. Ellsworth, Gregory C. Beroza

United States Geological Survey: Staff Publications

Near-source observations of five M 3.8-5.2 earthquakes near Ridgecrest, California are consistent with the presence of a seismic nucleation phase. These earthquakes start abruptly, but then slow or stop before rapidly growing again toward their maximum rate of moment release. Deconvolution of instrument and path effects by empirical Green's functions demonstrates that the initial complexity at the start of the earthquake is a source effect. The rapid growth of the P-wave arrival at the start of the seismic nucleation phase supports the conclusion of Mori and Kanamori [1996] that these earthquakes begin without a magnitude-scaled slow initial phase of the …


Seismic Rock-Physics Model For Carbonates At Low Effective Stress Levels Jan 1998

Seismic Rock-Physics Model For Carbonates At Low Effective Stress Levels

United States Geological Survey: Staff Publications

When considering the seismic response from the Dammam aquifer, the first required component is a simple model relating porosity and stress state to frame moduli assuming a carbonate matrix. We explored two such relationships, one based on the empirical regression presented by Domenico (1984) and a second using the critical porosity model of Nur et al. (1998) calibrated to the ultrasonic measurements of Nur and Simmons (1969). Once frame properties for a given porosity/pressure state were estimated, the effect of fluid changes were calculated using the low-frequency form of the Biot-Gassmann model, better known as Gassmann fluid substitution (Mavko …


Estimates Of Annual Survival Probabilities For Adult Florida Manatees (Trichechus Manatus Latirostris), C. A. Langtimm, T. J. O'Shea, R. Pradel, C. A. Beck Jan 1998

Estimates Of Annual Survival Probabilities For Adult Florida Manatees (Trichechus Manatus Latirostris), C. A. Langtimm, T. J. O'Shea, R. Pradel, C. A. Beck

United States Geological Survey: Staff Publications

The population dynamics of large, long-lived mammals are particularly sensitive to changes in adult survival. Understanding factors affecting survival patterns is therefore critical for developing and testing theories of population dynamics and for developing management strategies aimed at preventing declines or extinction in such taxa. Few studies have used modern analytical approaches for analyzing variation and testing hypotheses about survival probabilities in large mammals. This paper reports a detailed analysis of annual adult survival in the Florida manatee (Trichechus manatus latirostris), an endangered marine mammal, based on a mark-recapture approach. Natural and boat- inflicted scars distinctively "marked" individual …


Subsurface Heavy-Metal Detection With The Use Of A Laser-Induced Breakdown Spectroscopy (Libs) Penetrometer System, Brian Miles, Javier Cortes Jan 1998

Subsurface Heavy-Metal Detection With The Use Of A Laser-Induced Breakdown Spectroscopy (Libs) Penetrometer System, Brian Miles, Javier Cortes

US Army Corps of Engineers

U.S. Army Engineer Waterways Experiment Station (WES) investigators have designed, fabricated, and demonstrated a cone penetrometer sensor for subsurface in situ field screening based on LIBS. The LIBS probe (patent pending) presented here is one of a suite of contaminant and geophysical probes developed by the WES Site Characterization and Analysis Penetrometer System (SCAPS) program. The LIBS probe includes a laser as part of the optical LIBS sensor section for metals analysis and a cone and sleeve soil classification module at its tip. Soil classification data are acquired during the push, while LIBS data are recorded during probe retraction, after …


Madison County Test Hole Logs, Raymond R. Burchett Jan 1998

Madison County Test Hole Logs, Raymond R. Burchett

Conservation and Survey Division

No abstract provided.


Platte County Test Hole Logs, Raymond R. Burchett, Scott E. Summerside Jan 1998

Platte County Test Hole Logs, Raymond R. Burchett, Scott E. Summerside

Conservation and Survey Division

No abstract provided.


Resource Notes-Academic Year 1997-98 Jan 1998

Resource Notes-Academic Year 1997-98

Conservation and Survey Division

No abstract provided.


Nebraska Oil And Gas Production And Value For 1996 And 1997, R. R. Burchett, W. H. Sydow Jan 1998

Nebraska Oil And Gas Production And Value For 1996 And 1997, R. R. Burchett, W. H. Sydow

Conservation and Survey Division

No abstract provided.