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The Hydrology Of Shallow And Deep Aquifers In Relation To Secondary Soil Salinisation In Southwestern Australia, Richard J. George, Arthur J. Conacher Jun 1993

The Hydrology Of Shallow And Deep Aquifers In Relation To Secondary Soil Salinisation In Southwestern Australia, Richard J. George, Arthur J. Conacher

Natural Resources Research Articles

Results are reported from detailed research which has been carried out since 1984 on several Western Australian wheatbelt catchments, ranging in size from 12 ha to 1000 km2, in order to quantify the nature and roles of groundwater aquifers in relation to secondary salinisation. Secondary soil salinisation in the semi-arid wheatbelt has increased by 600% over the past 34 years to 440 000 ha, and is likely to increase by at least another 500% in the next 30-50 years. Changes in groundwater hydrology following the replacement of the native, woodland vegetation with agricultural crops and pastures during this century, have …


Arkansas Rice Research Studies 1992, B. R. Wells Jun 1993

Arkansas Rice Research Studies 1992, B. R. Wells

Arkansas Agricultural Experiment Station Research Series

The research reports in this publication represent one year of results; therefore, these results should not be used as a basis for longterm recommendations. Several research reports in this publication dealing with soil fertility also appear in Arkansas Soil Fertility Studies 1992, Arkansas Agricultural Experiment Station Research Series 425. This duplication is the result of the overlap in research coverage between the two series and our effort to inform Arkansas rice producers of all the research being conducted with funds from the rice check-off.


Scaling Water And Energy Fluxes In Climate Systems: Three Land-Atmospheric Modeling Experiments, Eric F. Wood, Venkataraman Lakshmi May 1993

Scaling Water And Energy Fluxes In Climate Systems: Three Land-Atmospheric Modeling Experiments, Eric F. Wood, Venkataraman Lakshmi

Faculty Publications

The effects of small-scale heterogeneity in land-surface characteristics on the large-scale fluxes of water and energy in the land-atmosphere system have become a central focus of many of the climatology research experiments. The acquisition of high-resolution land-surface data through remote sensing and intensive land-climatology field experiments(like HAPEX and EIFE) has provided data to investigate the interactions between microscale land-atmosphere interactions and macroscale models. One essential research question is how to account for the small-scale heterogeneities and whether `effective' parameters can be used in the macroscale models. To address this question ofscaling, three modeling experiments were performed and are reviewed in …


Internal Deformation, Evolution, And Fluid Flow In Basement-Involved Thrust Faults, Northwestern Wyoming, James V. Goddard May 1993

Internal Deformation, Evolution, And Fluid Flow In Basement-Involved Thrust Faults, Northwestern Wyoming, James V. Goddard

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

An integrated field, microstructure, fracture statistic , geochemistry, and laboratory permeability study of the East Fork and White Rock fault zones, of similar age and tectonic regime but different structural level and hydrogeologic history, provides detailed information about the internal deformation and fluid flow processes in fault zones. The primary conclusions of this research are: 1) Fault zones can be separated into subzones of protolith, damaged zone , and gouge /cataclasite, based on physical morphology and permeability structure. At deep structural levels, gouge/cataclasite zones are more evolved (thicker with increased grain size reduction) due to strain localization, higher pressure and …


Hydrogeology And Hydrochemistry Of The Delta Wadi El-Arish Area Sinai Peninsula, Egypt, Medhat A. El-Bihery May 1993

Hydrogeology And Hydrochemistry Of The Delta Wadi El-Arish Area Sinai Peninsula, Egypt, Medhat A. El-Bihery

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Delta Wadi El-Arish, Sinai Peninsula, Egypt, forms one of the most important parts of Egypt for industrial and agricultural expansion projects. This study focuses on the hydrogeology and the hydrochemistry of the Quaternary aquifer in the delta Wadi El-Arish area. Accurate information about the groundwater characteristics of the Quaternary aquifer will allow implementation of a sound water management policy for the Wadi El-Arish area.

The objectives of this study include: 1) determining the relationships between groundwater extraction and water levels and water quality using water-level measurements, total extraction of the wells, and chemical analyses of water samples; 2) determining the …


Geochemistry, Alluvial Facies Distribution, Hydrogeology, And Groundwater Quality Of The Dallas-Monmouth Area, Oregon, Rodney R. Caldwell Apr 1993

Geochemistry, Alluvial Facies Distribution, Hydrogeology, And Groundwater Quality Of The Dallas-Monmouth Area, Oregon, Rodney R. Caldwell

Dissertations and Theses

The Dallas-Monmouth area, located in the west-central Willamette Valley, Oregon, consists of Tertiary marine and volcanic bedrock units which are locally overlain by alluvium. The occurrence of groundwater with high salinities has forced many rural residents to use public water supplies. Lithologic descriptions from driller's logs, geochemical (INAA), and x-ray diffraction analyses were used to determine alluvial facies distribution, geochemical and clay mineral distinctions among the units, and possible sediment sources. Driller's log, chemical and isotopic analysis, and specific conductance information from wells and springs were used to study the hydrogeologic characteristics of the aquifers and determine the distribution, characteristics, …


Age Determination Of Recent Cave Deposits Using Excess 210Pb - A New Technique, M. Baskaran, Thomas M. Iliffe Apr 1993

Age Determination Of Recent Cave Deposits Using Excess 210Pb - A New Technique, M. Baskaran, Thomas M. Iliffe

Environmental Science and Geology Faculty Research Publications

Cave deposits have been widely used as proxy recorders in deciphering palaeoclimate during the last glacial/interglacial maxima (∼ 120 ka) [Harmon et al., 1975; Atkinson et al., 1978; Goede and Harmon, 1983; Ayliffe and Veeh, 1989]. Palaeoclimatic studies of cave deposits for the past 1–1000 yr time scale require a precise dating technique, that until now has been lacking. Due to the multiple sources of carbon in speleothems, 14C dates obtained for recently deposited calcite are highly variable and thus, 14C dating techniques are not suitable to obtain speleothem ages for the past 1–1000 years.

Here, we show …


Ground-Water Contamination By Volatile Organic Compounds: Sources Of Error, Temporal And Spatial Variability, Gary Thomas Blinkiewicz Apr 1993

Ground-Water Contamination By Volatile Organic Compounds: Sources Of Error, Temporal And Spatial Variability, Gary Thomas Blinkiewicz

Masters Theses

Data on the distributions of VOC’s (volatile organic compounds), principally trichloroethane and dichloroethylenes, in a shallow sand and gravel aquifer near Rockford, IL have been collected for a number of years. Synoptic sampling events from a dense monitoring well network within a greater than 4 mi^2 area, provide the basis for the evaluation of sources of variability in concentrations in space and time. Sampling, and analysis-related variability in these data contribute less than 10% of total variance. Spatial and temporal variability over periods of months to years are significant Results suggest that contaminant distributions can be resolved best by using …


Improved Filter-Pack Design For Hydrocarbon Recovery Wells In Unconsolidated Aquifers, Thomas R. Barrett Apr 1993

Improved Filter-Pack Design For Hydrocarbon Recovery Wells In Unconsolidated Aquifers, Thomas R. Barrett

Masters Theses

Laboratory sand tank experiments and two field studies were conducted to determine filter-pack designs that would increase the hydrocarbon flow rate into hydrocarbon recovery wells. Previous laboratory experiments have shown that using filter-packs of Teflon chips or sands treated with a water repellent spray will increase the rate of hydrocarbon recovery into wells in laboratory bail down test experiments.

The results of the laboratory investigations suggest that using a hydrophobic filter-pack with a median grain-size of 2.5-3.5 greater than that of the aquifer will provide the greatest rate of hydrocarbon recovery.

In two field studies, wells constructed with a hydrophobic …


Paleocene To Miocene Foraminifera From A Well Near Gloucester, Virginia, Nelson Stanley Ford Apr 1993

Paleocene To Miocene Foraminifera From A Well Near Gloucester, Virginia, Nelson Stanley Ford

OES Theses and Dissertations

Lithologic analysis of twenty-one core samples from a well near Gloucester, Virginia, when compared to published descriptions of formations occurring in the study area, indicates the presence of five formations. From oldest to youngest these units are the Aquia (late Paleocene), Nanjemoy (early Eocene), Chickahominy (late Eocene), Old Church (late Oligocene and early Miocene), and Eastover (late Miocene) formations. Comparison of the stratigraphic ranges of key planktic and benthic foraminifera from each of the core samples shows chronological agreement with previously published ages for each of these formations.

Paleoenvironmental analysis of each of the formations in the well is based …


Recent Benthic Foraminifera, Petrology, And Implications For Recent Transport In Wilmington And South Heyes Submarine Canyons, U.S. Atlantic Continental Margin, Jason James Lundquist Apr 1993

Recent Benthic Foraminifera, Petrology, And Implications For Recent Transport In Wilmington And South Heyes Submarine Canyons, U.S. Atlantic Continental Margin, Jason James Lundquist

OES Theses and Dissertations

Two hundred and forty-six species of benthic foraminifera have been recognized in fourteen short cores (≤ 24cm) taken from within the Wilmington and South Heyes submarine canyons along the slope and rise of the United States Atlantic Continental Margin. Of these one hundred and forty-five species were identified to the species level, thirty were closely related to known species, sixty-six could not be assigned specific names, and five species were of uncertain generic placement. The petrologic character of the sediments was determined for each of the seventy-eight micropaleontogical samples.

Cluster analysis of benthic foraminiferal data identified twelve groups which, together …


Paleobathymetric Interpretation Of Pleistocene Sediments In The South Padre Island Area, Northwestern Gulf Of Mexico, Using Benthic Foraminiferal Morphology, Karen Ianthe Kruebbe-Belwood Apr 1993

Paleobathymetric Interpretation Of Pleistocene Sediments In The South Padre Island Area, Northwestern Gulf Of Mexico, Using Benthic Foraminiferal Morphology, Karen Ianthe Kruebbe-Belwood

OES Theses and Dissertations

This study tested the validity of using intraspecific variation in benthic foraminifera as a means for determining Pleistocene paleobathymetry. Canonical variate analysis was used as a means for determining visually undetectable but statistically significant differences in the morphology of selected species. Two species, Cassidulina subglobosa and Uvigerina peregrina, were collected from Pleistocene well cuttings from the northwest Gulf of Mexico. The canonical analysis involved comparing the intraspecific variation of these Pleistocene species to their counterparts occurring in the modern Gulf of Mexico, where intraspecific variation was previously analyzed and found to be sufficient to allow detection of bathymetric differences …


Lithofacies Of The Pliocene-Pleistocene Lucayan Limestone, Great Abaco Island, Little Bahama Bank, Mary K. Mullen Apr 1993

Lithofacies Of The Pliocene-Pleistocene Lucayan Limestone, Great Abaco Island, Little Bahama Bank, Mary K. Mullen

OES Theses and Dissertations

Petrographic and sedimentologic analyses of eleven shallow subsurface cores (3 to 19 meters in length) from the Lucayan Limestone where it occurs along northeastern Great Abaco Island (little Bahama Bank) are used to delineate five carbonate lithofacies. The most prevalent lithofacies is a mottled, nonskeletal, peloidal packstone to grainstone. Other lithofacies include a rudstone, a laminated nonskeletal grainstone, a crossbedded grainstone and a mudstone-wackestone.

Cementation varies from poor to very well cemented core intervals. Cements observed included equant granular, equant blocky, drusy, meniscus, and needle fiber "whisker" cements. These cements reflect a variety of diagenetic environments such as the vadose, …


Assessment Of Watershed-Lake Interactions Influencing The Cultural Eutrophication Of Little Crooked & Crooked Lakes, Indiana, Thomas Crisman, William R. Demott, Paul M. Stewart Apr 1993

Assessment Of Watershed-Lake Interactions Influencing The Cultural Eutrophication Of Little Crooked & Crooked Lakes, Indiana, Thomas Crisman, William R. Demott, Paul M. Stewart

School of Geosciences Faculty and Staff Publications

No abstract provided.


Petrology Of A Large Granophyre-Rich Mesozoic Diabase Dike Near Farmville, Virginia, Philip Thomas Rogan Apr 1993

Petrology Of A Large Granophyre-Rich Mesozoic Diabase Dike Near Farmville, Virginia, Philip Thomas Rogan

OES Theses and Dissertations

Up to 37% granophyre occurs in the center of a 150m-wide Mesozoic diabase dike near Farmville, Virginia. The exceptional abundance of granophyre compared with other Mesozoic diabase dikes suggests unusual petrogenetic processes are involved in formation of the dike. Petrographic analyses show that granophyre increases from 5-10% near the flanks of the dike to a maximum of 37% in the core of the dike, and that granophyre distribution is approximately symmetrical about the center of the dike. Major and trace element concentrations parallel variations in the modal abundance of granophyre, with SiO2 , Na2O and K2 …


The Biogeochemistry Of Hydrogen Sulfide In The Open Ocean, Joël Radford-Knoery Apr 1993

The Biogeochemistry Of Hydrogen Sulfide In The Open Ocean, Joël Radford-Knoery

OES Theses and Dissertations

Hydrogen sulfide is a poorly quantified component of the global sulfur cycle. In seawater, its dissolved species (dissolved sulfide) can react with trace metals to form dissolved complexes and insoluble compounds. Therefore, the study of dissolved° sulfide in the open ocean can yield a better understanding of the biogeochemical cycles of sulfur and trace metals.

The biogeochemical cycling of dissolved sulfide was examined using specially developed sampling and analytical methods. In the western North Atlantic and central Equatorial Pacific Oceans, total dissolved sulfide concentrations ranged from /L; they were highest, in the mixed layer and decreased with depth. The depth …


Understanding Groundwater Starts With The Rocks: Geologic Fralnework, Groundwater Occurrence And Irrigation Development In Nebraska, Robert F. Diffendal Jr. Mar 1993

Understanding Groundwater Starts With The Rocks: Geologic Fralnework, Groundwater Occurrence And Irrigation Development In Nebraska, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

Nebraska is blessed with abundant groundwater. This groundwater is found beneath much of the state, principally in the sediments and sedimentary rocks that blanket the ancient and largely crystalline rocks geologists call Precambrian (see block diagram of Nebraska's geology, p. 50). These younger deposits contain pieces of evidence such as fossils and sedimentary features that reveal the tremendous changes in the environment that have gone on over the last 570 million years, during which these deposits accumulated. Change is the name of the game in geologic history, just as it is in human history. Fundamental changes in geologic history across …


Profiles: Nelson Horatio Darton: His Surveys Laid The Foundation, Robert F. Diffendal Jr. Mar 1993

Profiles: Nelson Horatio Darton: His Surveys Laid The Foundation, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

No serious researcher studying the development of water resources in Nebraska, or for that matter in the central Great Plains, can overlook the works of Nelson Horatio Darton, the first geologist to study and publish about those resources in any detail. Darton originally published the names and characteristics of many hydrogeologic units beneath much of Nebraska, now used by groups as diverse as scientists, well drillers and the general public. These works are listed below. As an indication of the value of these early efforts, I have used these works for my research and can testify to their accuracy and …


Flat Water: A History Of Nebraska And Its Water, Robert D. Kuzelka, Charles A. Flowerday, Robert N. Manley, Bradley C. Rundquist, Sally J. Herrin Mar 1993

Flat Water: A History Of Nebraska And Its Water, Robert D. Kuzelka, Charles A. Flowerday, Robert N. Manley, Bradley C. Rundquist, Sally J. Herrin

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Salinity - An Albany Perspective, Mandy Curnow Mar 1993

Salinity - An Albany Perspective, Mandy Curnow

Natural resources published reports

This booklet has been put together as an introduction to salinity in the Albany, Denmark, and Plantagenet districts. As much local information has been included as possible, so that the booklet will relate to your situation. The booklet looks at the causes of salinity and bow to recognise it. Included also, are methods of measuring salt in water and soil, both in the laboratory and the field. Methods of controlling salinity and reversing rising ground waters are not covered as there are already so many publications dealing with this topic.

Most agricultural areas experience some Ievel of salinity. Controlling salinity, …


Producing And Marketing Kentucky Hay - A Challenge, Ed Logsdon Feb 1993

Producing And Marketing Kentucky Hay - A Challenge, Ed Logsdon

Kentucky Alfalfa and Stored Forage Conference

Many of you probably are aware that Kentucky's commodity organizations are working with UK, the Agriculture Department and Farm Bureau in developing a plan to improve farm income in the state. This is a very ambitious project involving more than 40 farm organizations, including the Kentucky Forage and Grassland Council. This group has set a lofty goal of attempting to raise gross farm sales in the state from its current $3 billion level to around $5 billion by the turn of the century.


Alfalfa For Hay And Grazing In Tennessee, Joe Burns Feb 1993

Alfalfa For Hay And Grazing In Tennessee, Joe Burns

Kentucky Alfalfa and Stored Forage Conference

Alfalfa has truly had its "ups and downs" in terms of acreage in Tennessee for the last 30 years. Just as the effect of a good fertilizer-lime-soil testing program was increasing the alfalfa acreage, the alfalfa weevil appears and begins to destroy the crop. With the aid of the insecticide heptachlor sprayed on the fertilizer, farmers continued to fertilize the alfalfa and kill the weevil at the same time.


Grazing Alfalfa — National Perspective, Warren C. Thompson Feb 1993

Grazing Alfalfa — National Perspective, Warren C. Thompson

Kentucky Alfalfa and Stored Forage Conference

The production of alfalfa specifically for grazing is a fairly new practice. But now, farmers all around the USA are beginning to look toward alfalfa for a long living legume to increase yield, quality, and reliability all during the growing and grazing seasons. They also are looking for ways to reduce the cost of harvest, equipment, and storage costs, as well as weather-related harvest losses, and in time, reduced fertilizer costs.


Grazing Alfalfa — State Perspective, W. Roy Burris, Garry D. Lacefield Feb 1993

Grazing Alfalfa — State Perspective, W. Roy Burris, Garry D. Lacefield

Kentucky Alfalfa and Stored Forage Conference

Alfalfa has been grown in Kentucky for many years, but in the last decade, its acreage has increased dramatically- from 208,000 in 1978 to 350,000 in 1981 (Ky. Agri. Statistics Service). Alfalfa is generally thought of as a hay crop but the practice of grazing alfalfa has received considerable attention recently. Much of this interest was generated by "Graze-More-Beef" demonstrations which have been conducted in the state. Demonstrations in which alfalfa was grazed averaged 791 pounds per acre during 1986-1988. Alfalfa's ability to withstand dry weather and its excellent nutritional qualities make it an attractive grazing alternative to fescue - …


Do's And Don'ts Of Alfalfa Grazing, Ken Johnson Feb 1993

Do's And Don'ts Of Alfalfa Grazing, Ken Johnson

Kentucky Alfalfa and Stored Forage Conference

I usually start grazing in April when alfalfa is about 10 inches tall. I like to start with enough cattle to graze a paddock clean in two to five days, then move to another paddock, returning to re-graze in about 35 days. I usually need at least eight paddocks in the system. You must rotate cattle on Alfalfa for the stand to persist. It will take seven or eight head of 500 pound calves per acre to keep up with alfalfa growth in the spring. Part of the calves will need to be removed in June and maybe some more …


Grazing Alfalfa — County Perspective, Steve Osborne Feb 1993

Grazing Alfalfa — County Perspective, Steve Osborne

Kentucky Alfalfa and Stored Forage Conference

Often the difference between successful farming operations and others is the ability of the producers to manage the available resources to their advantage. The rolling topography and plentiful supply of livestock water in Monroe County is well suited to forage production. The purpose of this program is to introduce new forage species, improve forage production, and increase producer profits.


Grazing Alfalfa — An Overview, Garry D. Lacefield, W. Roy Burris Feb 1993

Grazing Alfalfa — An Overview, Garry D. Lacefield, W. Roy Burris

Kentucky Alfalfa and Stored Forage Conference

Alfalfa is the most important forage legume grown in the United States. Grown over a wide range of soil and climatic conditions it has the highest yield potential and feeding value of all perennial forage legumes. This versatile crop can be used for hay, pasture, silage, green-chop, pellets, cubes and soil improvement. Because of its many merits, especially yield, quality and versatility, it can be used successfully in many animal feeding programs.

Grazing alfalfa has not been practiced to any great extent in the U.S., but has been done extensively in other countries. Research and producer experience has shown excellent …


Quality From The Seed To The Sale To The Animal, Jimmy C. Henning, Garry D. Lacefield Feb 1993

Quality From The Seed To The Sale To The Animal, Jimmy C. Henning, Garry D. Lacefield

Kentucky Alfalfa and Stored Forage Conference

Forages in Kentucky have been valued at over $700 million annually. This figure combines receipts from cash hay sales to indirect value from the portion of beef, dairy, sheep, and horse receipts that are attributable to pasture and stored forages. However, the key to the maintaining and even increasing the value of forages to Kentucky lies in Quality: A) Quality of seed B) Quality as it relates to sales, and C) Quality as it relates to the animal.


New Developments In Hay Harvesting, Michael Collins Feb 1993

New Developments In Hay Harvesting, Michael Collins

Kentucky Alfalfa and Stored Forage Conference

Hay and pasture crops are critical to Kentucky Agriculture and to that of the entire temperate region of the US. The sale of cattle, calves and dairy products provide 29% of Kentucky's farm income compared with 23% for tobacco. Beef cowcalf enterprises comprise the majority of cattle numbers in the state, however, dairy production is also significant. A substantial horse industry also exists in Kentucky which is an excellent market for high quality alfalfa hay. At present a substantial amount of alfalfa for feeding horses in the state is imported.


My Observations And Experiences With Alfalfa, Larry Jeffries Feb 1993

My Observations And Experiences With Alfalfa, Larry Jeffries

Kentucky Alfalfa and Stored Forage Conference

I was raised on a small dairy farm in Henry County, Kentucky. I'm the oldest of six children and wanted to leave the farm as soon as possible. Upon graduation from Transylvania College in 1956, I was quickly drafted into the U.S. Army. I was sent to El Paso, Texas, for training and remained in the southwest for 11 (eleven) years.

In 1958 I married Carolyn Billman. We have 4 (four) children: Rae Lynne, Janet, Keith, and Joy.

Upon returning home to Henry County to farm and teach school in 1967, I found a catastrophe had happened to the alfalfa …