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The Impact Of Glacier Recession Upon The Discharge Of The Bow River Above Banff, Alberta, 1951-1993, Christopher Dennis Hopkinson Jan 1997

The Impact Of Glacier Recession Upon The Discharge Of The Bow River Above Banff, Alberta, 1951-1993, Christopher Dennis Hopkinson

Theses and Dissertations (Comprehensive)

Three methods have been used to explore the volumetric change of glaciers in the Bow Basin above Banff for the years 1951 to 1993. Using aerial photography, the extent of glacier covers for the two years were mapped at a scale of 1:50,000. The first volumetric calculation of glacier loss was based on inventory criteria; the second a hyposgraphic curve method based on Young’s investigations in Mistaya Basin (1991) and the third stereo air photogrammetry and DEM comparisons using computer software. These methods were applied to the highly glacierized Hector Lake catchment within the Bow Valley and then extrapolated up …


Spatial Distribution Of Lead In Soil And Sediment In Iqaluit, Northwest Territories And Links With Human Health, Liisa Ann Peramaki Jan 1997

Spatial Distribution Of Lead In Soil And Sediment In Iqaluit, Northwest Territories And Links With Human Health, Liisa Ann Peramaki

Theses and Dissertations (Comprehensive)

The Baffin Regional Health Board has recently expressed concern over lead poisoning in Iqaluit, NWT, manifested by low haemoglobin levels in children. Several studies in temperate regions have demonstrated links between environmental lead and human health. However, little is known about these links in a permafrost environment. While humans are exposed to lead via a number of different pathways, soils and sediments are two major pathways. The purpose of this study is to determine the spatial distribution of soil and sediment-associated lead in Iqaluit and to assess probable pathways between high lead levels and children. The research hypothesis is that …


Fluid Patterns, Sediment Pathways And Woody Obstructions In The Pine River, Angus, Ontario, John T. Beebe Jan 1997

Fluid Patterns, Sediment Pathways And Woody Obstructions In The Pine River, Angus, Ontario, John T. Beebe

Theses and Dissertations (Comprehensive)

The objective of this research was to determine the effects that woody obstructions have on flow patterns and sediment pathways in a sand-bed river in Central Ontario. The Pine River near Angus, a tributary of the Nottawasaga River, was chosen because it contained a number of woody obstructions to flow from which to choose study sites. Two reaches, one containing a trunk oriented in the direction of flow, were chosen as the study reaches. Sampling of fluid speeds through the study reaches showed that the cross-stream obstruction acted to slow fluid as it approached and exited the obstruction zone, while …


Petrogenesis Of Mid-Proterozoic Granitic Magmas: Examples From Central And West Texas, Diane R. Smith, C. Barnes, W. Shannon, R. Roback, E. James Jan 1997

Petrogenesis Of Mid-Proterozoic Granitic Magmas: Examples From Central And West Texas, Diane R. Smith, C. Barnes, W. Shannon, R. Roback, E. James

Earth and Environmental Geosciences Faculty Research

Circa 1.1 Ga granitic magmatism in Texas was manifested as two compositional groups: (1) the 1.12 Ga Red Bluff granitic suite in west Texas; and (2) 1.12-1.07 Ga granites of the Llano uplift of central Texas. Both suites share some characteristics typical of 'anorogenic' granites (e.g. potassium- and iron-rich bulk compositions, Fe-rich hydrous silicates, emplacement conditions involving low oxygen fugacities and water contents) and exhibit similar isotopic characteristics. However, rock associations, mineral chemistries, and trace element compositions of the two suites are distinct and no single petrogenetic model for the two suites is possible.

The Red Bluff granitic suite includes …


Discovery Of Fossil Cretaceous Bird In Southwest Arkansas, Leo Carson Davis, Kathie Harris Jan 1997

Discovery Of Fossil Cretaceous Bird In Southwest Arkansas, Leo Carson Davis, Kathie Harris

Journal of the Arkansas Academy of Science

No abstract provided.


Focus Catchments : A New Approach To Salinity Research : National Dryland Salinity Program, Steve Porritt Jan 1997

Focus Catchments : A New Approach To Salinity Research : National Dryland Salinity Program, Steve Porritt

Journal of the Department of Agriculture, Western Australia, Series 4

Dry/and salinity is a major threat to the resource base of many rural industries around Australia. More than 1.8 million hectares of once productive land are affected by salinity, with a further 1.6 million hectares at risk in the next 15 to 25 years in Western Australia alone. Much of the past Commonwealth and State expenditure on salinity programs and activities has been poorly targeted and coordinated. In view of this, a national dry/and salinity program that supports specific State salinity management programs has been established jointly between the Commonwealth and State government agencies.

The Upper Kent River Catchment is …


Hydrogeological And Hydrochemical Connection Between The Decatur City Spring And Crystal Lake, Benton County, Arkansas, Demetra O. Salisbury, Ralph K. Davis Jan 1997

Hydrogeological And Hydrochemical Connection Between The Decatur City Spring And Crystal Lake, Benton County, Arkansas, Demetra O. Salisbury, Ralph K. Davis

Journal of the Arkansas Academy of Science

Arkansas is ranked nationally in the production of broilers, laying hens, turkey, swine and beef cattle. These animals produce large volumes of waste, which are spread on pasture land as a method of disposal, as well as a source of fertilizer, resulting in nonpoint source contamination of surface water and ground water. One area of concern includes the Decatur City Spring, which provides municipal water for the city of Decatur. A total of eight sites in the surrounding area were monitored routinely for water quality parameters, including pH, specific conductance, and nitrate-nitrogen. Water temperature and spring and lake stage were …


A Memorial And Dedication: Susan Jenks Gaffey (1946–1995), H. Allen Curran, Michael J. Gaffey Jan 1997

A Memorial And Dedication: Susan Jenks Gaffey (1946–1995), H. Allen Curran, Michael J. Gaffey

Geosciences: Faculty Publications

Reprinted from: James L. Carew (ed.), Proceedings of the 8th Symposium on the Geology of the Bahamas and Other Carbonate Regions: San Salvador, Bahamian Field Station


Guide To Bahamian Ichnology: Pleistocene, Holocene, And Modern Environments: A Field Trip Guide, H. Allen Curran, Brian White, Mark A. Wilson Jan 1997

Guide To Bahamian Ichnology: Pleistocene, Holocene, And Modern Environments: A Field Trip Guide, H. Allen Curran, Brian White, Mark A. Wilson

Geosciences: Faculty Publications

This guide was prepared for the Fourth International Ichnofabric Workshop (IIW- 4) to be hosted by the Bahamian Field Station and held on San Salvador Island on March 15-22, 1997. About 35 scientists representing 15 countries are registered to attend the workshop.

The focus of discussion in the infonnal scientific sessions will be the uses of ichnofabric analysis in sedimentary geology. An ichnofabric is the texture or internal structure created within a sedimentary substrate from the bioturbating activity of organisms. Ichnofabric analysis is a new and emerging area of ichnology (the study of trace fossils), and its methods are proving …


Glacial Deposits, Vol. 25, 1996-1997, Department Of Geography-Geology Jan 1997

Glacial Deposits, Vol. 25, 1996-1997, Department Of Geography-Geology

Glacial Deposits

Newsletter of the Department of Geography-Geology


Ground Water, Robert F. Diffendal Jr. Jan 1997

Ground Water, Robert F. Diffendal Jr.

Department of Earth and Atmospheric Sciences: Faculty Publications

A geologic overview of the groundwater supply underlying Cheyenne County, Nebraska (1997).


Relations Between Directional Spectral Vegetation Indices And Leaf Area And Absorbed Radiation In Alfalfa, Elizabeth Walter-Shea, Jeffrey L. Privette, D. Cornell, Mark A. Mesarch, C. Hays Jan 1997

Relations Between Directional Spectral Vegetation Indices And Leaf Area And Absorbed Radiation In Alfalfa, Elizabeth Walter-Shea, Jeffrey L. Privette, D. Cornell, Mark A. Mesarch, C. Hays

Department of Earth and Atmospheric Sciences: Faculty Publications

s ensors on satellite platforms with extreme view angles have been increasingly used to analyze regional and global vegetation cover and productivity because of frequent observations. This study, using experimental and theoretical methods, analyzed variations in vegetation indices with sun-view geometry as a means of understanding the sensitivity of relations beween vegetation indices and the biophysical properties, the leaf area index (LAI), and the instantaneous fraction of absorbed photosynthetically active radiation (fAPAR). Canopy bidirectional reflectance factors (BRFs) of an alfalfa crop were measured and simulated at a variety of solar and view zenith angles. Also, fAPAR, LAI, and leaf optical …


Field Trip Guide ( For The Nebraska Well Drillers Association) Western Nebraska Geology, S. Sibray, D. Heinen, D. Eversoll, R. Tremblay, J. Cannia, J. Belieu Jan 1997

Field Trip Guide ( For The Nebraska Well Drillers Association) Western Nebraska Geology, S. Sibray, D. Heinen, D. Eversoll, R. Tremblay, J. Cannia, J. Belieu

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Explanation Of Geologic Map Units For Use With University Of Nebraska-Lincoln Conservation And Survey Division Open-File Maps Nos. 53-65., Hannan E. Lagarry, Leigh Anne Lagarry Jan 1997

Explanation Of Geologic Map Units For Use With University Of Nebraska-Lincoln Conservation And Survey Division Open-File Maps Nos. 53-65., Hannan E. Lagarry, Leigh Anne Lagarry

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Franklin County Test Hole Logs, Raymond R. Burchett, Scott E. Summerside Jan 1997

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

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Fillmore County Test Hole Logs, Raymond R. Burchett, Scott E. Summerside Jan 1997

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

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Resource News-Winter 1996-97 Jan 1997

Resource News-Winter 1996-97

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Resource News-Spring 1997 Jan 1997

Resource News-Spring 1997

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Resource News-Summer 1997 Jan 1997

Resource News-Summer 1997

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Structural Contour Map On Top Of The Lansing Group (Pennsylvanian) In Dundy County, Nebraska, R. R. Burchett Jan 1997

Structural Contour Map On Top Of The Lansing Group (Pennsylvanian) In Dundy County, Nebraska, R. R. Burchett

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Herbicides And Their Metabolites In Rainfall: Origin, Transport, And Deposition Patterns Across The Midwestern And Northeastern United States, 1990-1991, Donald Goolsby, E. Michael Thurman, Michael Pomes, Michael Meyer, William Battaglin Jan 1997

Herbicides And Their Metabolites In Rainfall: Origin, Transport, And Deposition Patterns Across The Midwestern And Northeastern United States, 1990-1991, Donald Goolsby, E. Michael Thurman, Michael Pomes, Michael Meyer, William Battaglin

United States Geological Survey: Staff Publications

Herbicides were detected in rainfall throughout the midwestern and northeastern United States during late spring and summer of 1990 and 1991. Herbicide concentrations exhibited distinct geographic and seasonal patterns. The highest concentrations occurred in midwestern cornbelt states following herbicide application to cropland. Volume-weighted concentrations of 0.2-0.4 μg/L for atrazine and alachlor were typical in this area during mid-April through mid-July, and weighted concentrations as large as 0.6- 0.9 μg/L occurred at several sites. Concentrations of 1-3 μg/L were measured in a few individual samples. Atrazine was detected most often followed by alachlor, deethylatrazine, metolachlor, cyanazine, and deisopropylatrazine. The high ratio …


Geology, Robert F. Diffendal Jr. Jan 1997

Geology, Robert F. Diffendal Jr.

Department of Earth and Atmospheric Sciences: Faculty Publications

An overview of the geology of Cheyenne County, Nebraska.


Fractured-Aquifer Hydrogeology From Geophysical Logs; The Passaic Formation, New Jersey, Roger H. Morin, Glen B. Carleton, Stephane Poirier Jan 1997

Fractured-Aquifer Hydrogeology From Geophysical Logs; The Passaic Formation, New Jersey, Roger H. Morin, Glen B. Carleton, Stephane Poirier

United States Geological Survey: Staff Publications

The Passaic Formation consists of gradational sequences of mudstone, siltstone, and sandstone, and is a principal aquifer in central New Jersey. Ground-water flow is primarily controlled by fractures interspersed throughout these sedimentary rocks and characterizing these fractures in terms of type, orientation, spatial distribution, frequency, and transmissivity is fundamental towards understanding local fluid-transport processes. To obtain this information, a comprehensive suite of geophysical logs was collected in 10 wells roughly 46 m in depth and located within a .05 km2 area in Hopewell Township, New Jersey. A seemingly complex, heterogeneous network of fractures identified with an acoustic televiewer was …


Three-Dimensional Upper Crustal Velocity Structure Beneath San Francisco Peninsula, California, Tom Parsons, Mary Lou Zoback Jan 1997

Three-Dimensional Upper Crustal Velocity Structure Beneath San Francisco Peninsula, California, Tom Parsons, Mary Lou Zoback

United States Geological Survey: Staff Publications

This paper presents new seismic data from, and crustal models of the San Francisco Peninsula. In much of central California the San Andreas fault juxtaposes the Cretaceous granitic Salinian terrane on its west and the Late Mesozoic/Early Tertiary Franciscan Complex on its east. On San Francisco Peninsula, however, the present-day San Andreas fault is completely within a Franciscan terrane, and the Pilarcitos fault, located southwest of the San Andreas, marks the Salinian-Franciscan boundary. This circumstance has evoked two different explanations: either the Pilarcitos is a thrust fault that has pushed Franciscan rocks over Salinian rocks or the Pilarcitos is a …


Nearly Synchronous Climate Change In The Northern Hemisphere During The Last Glacial Termination, Larry V. Benson, James Burdett, Steve Lund, Michaele Kashgarian, Scott Mensing Jan 1997

Nearly Synchronous Climate Change In The Northern Hemisphere During The Last Glacial Termination, Larry V. Benson, James Burdett, Steve Lund, Michaele Kashgarian, Scott Mensing

United States Geological Survey: Staff Publications

The climate of the North Atlantic region underwent a series of abrupt cold/warm oscillations when the ice sheets of the Northern Hemisphere retreated during the last glacial termination (17,700–11,500 years ago). Evidence for these oscillations, which are recorded in European terrestrial sediments as the Oldest Dryas/Bølling/ Older Dryas/Allerød/Younger Dryas vegetational sequence, has been found in Greenland ice cores. The geographical extent of many of these oscillations is not well known, but the last major cold event (the Younger Dryas) seems to have been global in extent. Here we present evidence of four major oscillations in the hydrological balance of the …


Correlation Of Late-Pleistocene Lake-Level Oscillations In Mono Lake, California, With North Atlantic Climate Events, Larry Benson, Steve P. Lund, James W. Burdett, Michaele Kashgarian, Timothy P. Rose, Joseph P. Smoot, Martha Schwartz Jan 1997

Correlation Of Late-Pleistocene Lake-Level Oscillations In Mono Lake, California, With North Atlantic Climate Events, Larry Benson, Steve P. Lund, James W. Burdett, Michaele Kashgarian, Timothy P. Rose, Joseph P. Smoot, Martha Schwartz

United States Geological Survey: Staff Publications

Oxygen-18 (18O) values of sediment from the Wilson Creek Formation, Mono Basin, California, indicate three scales of temporal variation (Dansgaard-Oeschger, Heinrich, and Milankovitch) in the hydrologic balance of Mono Lake between 35,400 and 12,900 14C yr B.P. During this interval, Mono Lake experienced four lowstands each lasting from 1000 to 2000 yr. The youngest low stand, which occurred between 15,500 and 14,000 14C yr B.P., was nearly synchronous with a desiccation of Owens Lake, California. Paleomagnetic secular variation (PSV) data indicate that three of four persistent low stands occurred at the same times as Heinrich events …


Soil Information Sheets For The Northern Agricultural Areas, Natural Resources Assessment Group, Agriculture Western Australia, Landcare Western Australia Jan 1997

Soil Information Sheets For The Northern Agricultural Areas, Natural Resources Assessment Group, Agriculture Western Australia, Landcare Western Australia

Agriculture reports

These soil information sheets are produced for farmers in the Northern Wheatbelt. Each sheet summaries information on the particular soil's characteristic properties and associated land use suitability and management. A photograph of a representative profile is provided for each soil. Technical terms are defined in the glossary. Information is presented under the following headings: Soil series and group, occurrence, native vegetation, soil profile description, characteristic soil properties, soil classification (Australian Soil Classification and Northcote Principal Profile Form).


Knickpoint Analysis Of Streams In North Dakota, South Dakota, And Nebraska, Trent D. Hubbard Jan 1997

Knickpoint Analysis Of Streams In North Dakota, South Dakota, And Nebraska, Trent D. Hubbard

Theses and Dissertations

Analysis of stream profiles, seismic reflection studies, engineering studies, and historical earthquakes indicates uplift in south-central South Dakota and north-central Nebraska over the last 5-10 ma. The purpose of this study was to determine if this uplift could be detected by constructing topographic profiles along, and in close proximity to several streams in this region. The Cannonball River, ND, was used to compare the streams in South Dakota and Nebraska to a stream beyond the affected area.

Data for the profiles were collected from 7 .5 minute topographic maps as well as GPS surveys. Abrupt changes in slope (irregularities) were …


Timing Of Basaltic Volcanism Along The Mesa Butte Fault In The San Francisco Volcanic Field, Arizona, From 40Ar/39Ar Dates: Implications For Longevity Of Cinder Cone Alignments, F. M. Conway, David A. Ferrill, Chris M. Hall, Alan P. Morris, John A. Stamatakos, Charles B. Connor, Alex N. Halliday, Christopher Condit Jan 1997

Timing Of Basaltic Volcanism Along The Mesa Butte Fault In The San Francisco Volcanic Field, Arizona, From 40Ar/39Ar Dates: Implications For Longevity Of Cinder Cone Alignments, F. M. Conway, David A. Ferrill, Chris M. Hall, Alan P. Morris, John A. Stamatakos, Charles B. Connor, Alex N. Halliday, Christopher Condit

School of Geosciences Faculty and Staff Publications

Using high‐precision stepwise‐heating 40Ar/39Ar methods, we dated volcanic products of at least 12 vents cropping out along the northern segment of the Mesa Butte Fault in the San Francisco Volcanic Field, Arizona, where the relationship between fault and vent alignment is unambiguous. The 40Ar/39Ar isochron dates indicate that the Mesa Butte Fault hosted five episodes of volcanism over a 1 million year interval, from 1400 to 300 ka. The first episode occurred 1 km northwest of the trace of the Mesa Butte Fault, whereas the next two episodes were centered near the intersection of the Mesa Butte and Cedar Ranch …


A Strategy For Monitoring Glaciers, Andrew G. Fountain, Robert M. Krimmel, Dennis C. Trabant Jan 1997

A Strategy For Monitoring Glaciers, Andrew G. Fountain, Robert M. Krimmel, Dennis C. Trabant

Geography Faculty Publications and Presentations

Glaciers are important features in the hydrologic cycle and affect the volume, variability, and water quality of runoff. Assessing and predicting the effect of glaciers on water resources require a monitoring program to provide basic data for this understanding. The monitoring program of the U.S. Geological Survey employs a nested approach whereby an intensively studied glacier is surrounded by less intensively studied glaciers and those monitored solely by remote sensing. Ideally, each glacierized region of the United States would have such a network of glaciers. The intensively studied glacier provides a detailed understanding of the physical processes and their temporal …