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Vsp Traveltime Inversion: Near-Surface Issues, Geoff J. M. Moret, William P. Clement, Michael D. Knoll, Warren Barrash Mar 2004

Vsp Traveltime Inversion: Near-Surface Issues, Geoff J. M. Moret, William P. Clement, Michael D. Knoll, Warren Barrash

Geosciences Faculty Publications and Presentations

P-wave velocity information obtained from vertical seismic profiles (VSPs) can be useful in imaging subsurface structure, either by directly detecting changes in the subsurface or as an aid to the interpretation of seismic reflection data. In the shallow subsurface, P-wave velocity can change by nearly an order of magnitude over a short distance, so curved rays are needed to accurately model VSP traveltimes. We used a curved-ray inversion to estimate the velocity profile and the discrepancy principle to estimate the data noise level and to choose the optimum regularization parameter. The curved-ray routine performed better than a straight-ray inversion for …


Groundwater Study Of The Narrogin Townsite, Edward K. Crossley Mar 2004

Groundwater Study Of The Narrogin Townsite, Edward K. Crossley

Resource management technical reports

A groundwater study was carried out in the townsite of Narrogin, Western Australia, in April 2002. The study consisted of a drilling program to install a network of groundwater monitoring bores. This report contains background information for the town and its catchment, the climatic, geological and hydrogeological investigations, and conclusions on the town's salinity risk and recommendations for improved water management.


Groundwater Trends In The Central Agricultural Region, S Ghauri Mar 2004

Groundwater Trends In The Central Agricultural Region, S Ghauri

Resource management technical reports

This report provides an update of groundwater data and interpretation for each of the hydrozones of the central agricultural region in Western Australia.


General Brochure, University Of North Dakota. Energy And Environmental Research Center Mar 2004

General Brochure, University Of North Dakota. Energy And Environmental Research Center

EERC Brochures and Fact Sheets

Brochure about the Energy & Environmental Research Center, including its philosophy, program areas, and Centers of Excellence. [This item is an outdated or superseded version and retained for historical purposes only. It may no longer reflect current information, policies, or practices].


Ground Water Level Measurements In Selected Boreholes Near The Site Of The Proposed Repository, H. Scott Page, Klaus J. Stetzenbach, Drew Coleman, Don Baepler, Amy J. Smiecinski Mar 2004

Ground Water Level Measurements In Selected Boreholes Near The Site Of The Proposed Repository, H. Scott Page, Klaus J. Stetzenbach, Drew Coleman, Don Baepler, Amy J. Smiecinski

Publications (YM)

The objective of this task is to provide ground water level measurements of known accuracy and precision using manual and electronic methods. The HRC will use field-proven protocols and established implementing procedures for all aspects of data collection, analysis, management, and reporting. The water level measurements produced by this program will yield quality-assured data that can be reliably used for a variety of purposes including: continued site characterization, refinement of the local potentiometric surface, inputs to the Death Valley Regional Flow Model and related hydrologic characterization, to fulfill permit conditions issued by the State of Nevada, to monitor seismically-induced ground …


Changes In Sulfur Concentration And Sulfur Isotopic Composition Within Authigenic Sulfide Minerals From Sediments Of Miocene Age To The Present, Odp Site 995, Blake Ridge, Offshore Southeastern United States, Kathryn G. Takacs, Walter S. Borowski Mar 2004

Changes In Sulfur Concentration And Sulfur Isotopic Composition Within Authigenic Sulfide Minerals From Sediments Of Miocene Age To The Present, Odp Site 995, Blake Ridge, Offshore Southeastern United States, Kathryn G. Takacs, Walter S. Borowski

EKU Faculty and Staff Scholarship

The Blake Ridge area (offshore southeastern United States) consists of deep-water continental margin sediments overlying deposits of methane gas hydrate. Authigenic sulfide minerals (elemental sulfur, S˚; iron monosulfides, ~FeS; and pyrite, FeS2) are actively deposited in these sediments due to sulfate reduction and focused anaerobic methane oxidation (AMO) at the sulfate-methane interface (SMI). Sulfide minerals at the present SMI are enriched in 34S relative to those produced by sulfate reduction of organic matter higher in the sulfate reduction zone. 34S enrichments preserved in the sediment column may identify relatively high amounts of AMO and thus record …


Inside Unlv, Gian Galassi, Carol C. Harter, Kenneth E. Marks Mar 2004

Inside Unlv, Gian Galassi, Carol C. Harter, Kenneth E. Marks

Inside UNLV

No abstract provided.


Drift Scale Test: Analyze And Report, George Danko, Davood Bahrami, Amy J. Smiecinski Mar 2004

Drift Scale Test: Analyze And Report, George Danko, Davood Bahrami, Amy J. Smiecinski

Publications (YM)

This report summarizes the results of the in situ thermophysical properties measurements as part of the Drift Scale Test (DST) measurement program at Yucca Mountain, Nevada. Thermophysical measurements have been performed with three built-in thermal probes since November 13, 1997 and were expected to continue for three more years until the end of the DST cooling period. The Department of Energy (DOE), under Cooperative Agreement, Number DEFC28- 98NV12081, has funded a research project at the University of Nevada, Reno since November, 1999 titled: "Continuing site characterization and performance verification applications with the REKA method at Yucca Mountain, Task 13." This …


Stress Corrosion Cracking Studies, K. S. Raja, S. Namjoshi, Amy J. Smiecinski Mar 2004

Stress Corrosion Cracking Studies, K. S. Raja, S. Namjoshi, Amy J. Smiecinski

Publications (YM)

This document reports on the activities for Task 17 of the U.S. DOE/UCCSN Cooperative Agreement Number DE-FC28-98NV12081. There are three subtasks in this Task, the experimental results, discussions, and conclusions of which are presented in the following sections. Data Sources and Electronic Data Control The Data Identification numbers for the data, graphs, and tables in this report, as submitted to the Data Management Database, are tabulated below. The table also includes the source files for the said data as well as the corresponding scientific notebooks where the data can be found. All data in the Q section of the report …


Sulfide Mineralization In Deep-Water Marine Sediments Related To Methane Transport, Methane Consumption, And Methane Gas Hydrates, Matthew K. Thompson, Walter S. Borowski, Charles K. Paull, William Ussler Iii Mar 2004

Sulfide Mineralization In Deep-Water Marine Sediments Related To Methane Transport, Methane Consumption, And Methane Gas Hydrates, Matthew K. Thompson, Walter S. Borowski, Charles K. Paull, William Ussler Iii

EKU Faculty and Staff Scholarship

Patterns of sulfide sulfur concentration and sulfur isotopic composition (d34 S) are perhaps related to upward methane transport, especially in sediments underlain by methane gas hydrate deposits. Increased methane delivery augments the effect of anaerobic methane oxidation (AMO) occurring at the sulfate-methane interface (SMI). Sulfate and methane co-consumption results in production of dissolved sulfide at the interface that is eventually sequestered within sulfide minerals (elemental sulfur, iron monosulfide, pyrite).

We examine the sediments of two piston cores collected over the Blake Ridge gas hydrate deposits (offshore southeastern United States) by extracting total sedimentary sulfide using chromium reduction. We use …


Photos Of The 24th Kentucky Alfalfa Conference Award Winners, Kentucky Alfalfa Conference Feb 2004

Photos Of The 24th Kentucky Alfalfa Conference Award Winners, Kentucky Alfalfa Conference

Kentucky Alfalfa and Stored Forage Conference

No abstract provided.


Moisture--Temperature Management During Alfalfa Hay And Silage Making & Storing, Michael Collins Feb 2004

Moisture--Temperature Management During Alfalfa Hay And Silage Making & Storing, Michael Collins

Kentucky Alfalfa and Stored Forage Conference

In some areas of the country, producers store a substantial portion of their forage for winter feeding as silage or haylage. However, hay remains the most popular storage method for forage. Hay stores well for long periods and is better suited to cash sale and transportation than silage. Mechanical conditioning, which gained acceptance during the 1950's is probably still the greatest single change in hay harvesting and storage technology during this century. However, a number of other noteworthy changes and innovations have occurred in recent years which have helped to reduce the extent of losses during hay harvesting and storage.


Marketing Kentucky Alfalfa, Nicky Baker Feb 2004

Marketing Kentucky Alfalfa, Nicky Baker

Kentucky Alfalfa and Stored Forage Conference

The main key to marketing hay over the years is flexibility. Don’t gear up too heavy for the one specific market. Keep your options open and remember there aren’t any government payments.


Marketing Kentucky Alfalfa, Tom Keene Feb 2004

Marketing Kentucky Alfalfa, Tom Keene

Kentucky Alfalfa and Stored Forage Conference

In order to market Kentucky produced alfalfa, we need to go back and look at our operation to see if we can produce high quality alfalfa. We can start doing this by determining what the best land use is given the particular soils and typography that makes up your farm layout. There are other things we need to be aware of after we determine our ability to grow alfalfa; is the terrain suitable for harvesting alfalfa using different types of harvesting equipment? Also do we have the equipment necessary to produce alfalfa, either as a grazing tool, grass hay or …


Balancing Agronomics And Economics Of Alfalfa Hay Production, Brian Lacefield, Garry D. Lacefield Feb 2004

Balancing Agronomics And Economics Of Alfalfa Hay Production, Brian Lacefield, Garry D. Lacefield

Kentucky Alfalfa and Stored Forage Conference

Alfalfa has high-yielding, high-quality, persistent, and profitable potential if given adequate management and a balance of several agronomic and economic considerations. How can we account for the differences among producers who have the average alfalfa yields of 3.0 tons/A with the top hay producers who average approximately 5.0 tons/acre and the producer who has achieved the record yield of 10.13 tons/acre? Is the answer “luck”, better soils, moisture and growing conditions? The answer may certainly be yes, but. Yes, the factors above are important and can explain some differences; however, we believe the overall difference is the management of research-based …


Hybrid Alfalfa: Reality Or Pipe Dream? Dairyland Seed Company, Michael Velde Feb 2004

Hybrid Alfalfa: Reality Or Pipe Dream? Dairyland Seed Company, Michael Velde

Kentucky Alfalfa and Stored Forage Conference

Progress in increasing alfalfa forage yield has been minimal over the past 20 years. This is due primarily to lack of pollen control in open pollinated synthetic varieties. All alfalfa varieties to date have been open pollinated synthetic varieties. New alfalfa hybridization technology provides the tools to overcome the forage yield barriers that have been hindering alfalfa breeders from making progress


Roundup Ready Alfalfa Update, Daniel O. Foor Feb 2004

Roundup Ready Alfalfa Update, Daniel O. Foor

Kentucky Alfalfa and Stored Forage Conference

No abstract provided.


Establishing Alfalfa Using No-Till Techniques, Gary Bates Feb 2004

Establishing Alfalfa Using No-Till Techniques, Gary Bates

Kentucky Alfalfa and Stored Forage Conference

There have been many changes in agriculture over the last 50 years. One of the greatest has been the use of no-till planting methods. The development of drill and herbicides has made no-till seedings as successful as seeding into prepared land.


Measuring Hay Temperatures, Doug Overhults Feb 2004

Measuring Hay Temperatures, Doug Overhults

Kentucky Alfalfa and Stored Forage Conference

It is well known that baling hay at the right moisture content is the key to preventing excessive heating in the bale. It can be quite a challenge, though, to get all of the hay baled without some of it being a bit wetter than is desirable. That’s when trouble can begin, and we have to be concerned about heating that could damage the hay or even lead to spontaneous combustion. Fortunately, the heating process does take some time to develop and we do know what temperatures signal that a critical situation may be developing. So, monitoring bale or stack …


Fertilizing Alfalfa For Profit, Monroe Rasnake Feb 2004

Fertilizing Alfalfa For Profit, Monroe Rasnake

Kentucky Alfalfa and Stored Forage Conference

Alfalfa has a high yield potential in relation to most other forages. However, this potential can only be realized on a long-term basis if the nutrient needs of the plant are adequately provided for. In addition, the ability of alfalfa plants to survive the heat and drought of summer and the cold of winter depends on an abundant supply of plant nutrients.


Grazing Alfalfa, Garry D. Lacefield Feb 2004

Grazing Alfalfa, Garry D. Lacefield

Kentucky Alfalfa and Stored Forage Conference

Over the past decade we have had several people address “Alfalfa as a Grazing Crop” including Warren Thompson, Gary Bates, Ken Johnson, Jason Sandefur, Byron Sleugh, and myself. Each has done an excellent job discussing the merits of this remarkable crop and the opportunities it offers for grazing. At the end of the Conference last year, I (as I always do) asked for your suggestions concerning topics for this years’ conference. As it has been for the past decade, “Grazing” was the most requested topic. In today’s presentation, let’s go back and revisit the question, “Is Grazing Alfalfa Right for …


Foreword And Recipients Of Kentucky Alfalfa Awards [2004], Garry D. Lacefield, Christi L. Forsythe Feb 2004

Foreword And Recipients Of Kentucky Alfalfa Awards [2004], Garry D. Lacefield, Christi L. Forsythe

Kentucky Alfalfa and Stored Forage Conference

No abstract provided.


Yucca Mountain Climate Technical Support Representative, Saxon E. Sharpe, Dick Reinhardt, Eric Smistad, Don Baepler, Amy J. Smiecinski Feb 2004

Yucca Mountain Climate Technical Support Representative, Saxon E. Sharpe, Dick Reinhardt, Eric Smistad, Don Baepler, Amy J. Smiecinski

Publications (YM)

The principal investigator (PI), Saxon Sharpe, for Task ORD-FY04-012, DOE Cooperative Agreement DE-FC28-04RW12232, will serve as Yucca Mountain Climate Technical Support Representative for the Department of Energy (DOE) in a series of activities related to past, present, and future climate for the Yucca Mountain Project (YMP) climate program.

As stated in the Viability Assessment of a Repository at Yucca Mountain: “Climate and its changes over time directly affect system performance at Yucca Mountain.” Currently, information from climate studies is used in models that support the Total System Performance Assessment and Licensing Application. It is a model component of all key …


Southern Great Basin Seismic Network Operations, David Von Seggern, James N. Brune, Rasool Anooshehpoor, Drew Coleman, Don Baepler, Amy J. Smiecinski Feb 2004

Southern Great Basin Seismic Network Operations, David Von Seggern, James N. Brune, Rasool Anooshehpoor, Drew Coleman, Don Baepler, Amy J. Smiecinski

Publications (YM)

QAP-3.0 (Scientific Investigation Control) of the University and Community College System of Nevada (UCCSN) Quality Assurance (QA) program requires that, prior to initiating work, a Scientific Investigation Plan (SIP) must be prepared and approved. This SIP is intended to cover the seismic monitoring task performed by the Nevada Seismological Laboratory (NSL). The purpose of this SIP is to describe the high-level planning for the overall task such that it can be referred to by individual scientific notebooks. Due to the continuation nature of this task, this SIP contains language that may be considered generic so that new subtasks …


Subsurface Acidity, Mike Bolland, Chris Gazey, Amanda Miller, Dave Gartner, Julie-Anne Roche Feb 2004

Subsurface Acidity, Mike Bolland, Chris Gazey, Amanda Miller, Dave Gartner, Julie-Anne Roche

Bulletins 4000 -

Productive agriculture increases the concentration of hydrogen ions in soil, which acidifies the soil.

Aluminium is a component of many soil constituents, including clays and oxides, and is also present on the surfaces of soil organic matter. As the concentration of hydrogen ions in soil increases, soil pH decreases, and aluminium starts to dissolve from the soil constituents, increasing the concentration of aluminium ions in soil solution.

As the concentration of aluminium ions in the solution increases, the aluminium in the soil solution becomes increasingly toxic to plant roots, reducing root growth. The smaller amounts of plant roots explore a …


Geomorphic And Environmental Change Around A Large, Aging Reservoir: Lake C. W. Mcconaughy, Western Nebraska, Usa, R. Matthew Joeckel, Robert F. Diffendal Jr. Feb 2004

Geomorphic And Environmental Change Around A Large, Aging Reservoir: Lake C. W. Mcconaughy, Western Nebraska, Usa, R. Matthew Joeckel, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

Lake C. W. McConaughy, a 63-year-old manmade reservoir in the North Platte Valley of western Nebraska, is the largest standing body of water in the state. From the time that Kingsley Dam was completed in 1941 until the present day (2004), many geomorphic and environmental changes have occurred along the shores and within the North Platte Valley. Erosion on the southeastern shoreline of the lake had been perceived as a problem for landowners and managers for at least three decades, but the full scale of erosion was revealed only after a cumulative 18-m drawdown in lake level: bedrock platforms, extending …


Narrogin Townsite Test Pumping Results 2003, Louise Hopgood Feb 2004

Narrogin Townsite Test Pumping Results 2003, Louise Hopgood

Resource management technical reports

Test pumping of a production bore in Narrogin took place for 24 hours in August 2003. Data generated by the test pumping was analysed along with groundwater monitoring, climate and geological data. Laboratory analyses of water samples from the production bore indicate very high levels of salinity and hardness which may lead to severe scaling and corrosion of pumps, pipes and pipe fittings.


Multivariate Analysis Of Cross-Hole Georadar Velocity And Attenuation Tomograms For Aquifer Zonation, Jens Tronicke, Klaus Holliger, Warren Barrash, Michael D. Knoll Jan 2004

Multivariate Analysis Of Cross-Hole Georadar Velocity And Attenuation Tomograms For Aquifer Zonation, Jens Tronicke, Klaus Holliger, Warren Barrash, Michael D. Knoll

CGISS Publications and Presentations

We have investigated the potential of combining cross-hole georadar velocity and attenuation tomography as a method for characterizing heterogeneous alluvial aquifers. A multivariate statistical technique, known as k-means cluster analysis, is used to correlate and integrate information contained in velocity and attenuation tomograms. Cluster analysis allows us to identify objectively the major common trends in the tomographic data and thus to ‘‘reduce’’ the information to a limited number of characteristic parameter combinations. The application of this procedure to two synthetic data sets indicates that it is a powerful tool for converting the complex relationships between the tomographically derived velocity …


Paleomagnetism And 40ar/39ar Chronology Of Lavas From Meseta Del Lago Buenos Aires, Patagonia, Laurie L. Brown, Brad S. Singer, Matthew L. Gorring Jan 2004

Paleomagnetism And 40ar/39ar Chronology Of Lavas From Meseta Del Lago Buenos Aires, Patagonia, Laurie L. Brown, Brad S. Singer, Matthew L. Gorring

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

[1] As part of a larger project investigating paleosecular variation in South America, 36 paleomagnetic and geochronology sites were sampled on Meseta del Lago Buenos Aires (47°S, 289°E), 200 km east of the active plate boundary in southern Patagonia. Basaltic lavas sampled range from late Miocene to late Pleistocene yet most of the individual lavas are younger than 3.3 Ma. Thirty-eight isochron ages determined via 40Ar/39Ar incremental-heating experiments frame a detailed stratigraphy. The isochron ages range from 66.9 ± 4.1 ka for scoria cones and a youthful lava flow in the Rio Pinturas valley to 10.12 ± 1.35 Ma for …


Dense Nonaqueous Phase Liquid (Dnapl) Source Zone Characterization: Influence Of Hydraulic Property Correlation On Predictions Of Dnapl Infiltration And Entrapment, Lawrence D. Lemke, Linda M. Abriola, Pierre Goovaerts Jan 2004

Dense Nonaqueous Phase Liquid (Dnapl) Source Zone Characterization: Influence Of Hydraulic Property Correlation On Predictions Of Dnapl Infiltration And Entrapment, Lawrence D. Lemke, Linda M. Abriola, Pierre Goovaerts

Environmental Science and Geology Faculty Research Publications

The influence of aquifer property correlation on multiphase fluid migration and entrapment was explored through the use of correlated and uncorrelated porosity, permeability, and capillary pressure-saturation (Pc-Sat) parameter fields in a crosssectional numerical multiphase flow model. Data collected from core samples in a nonuniform sandy aquifer were used to generate three-dimensional aquifer parameter fields. Porosity was assumed to be uniform or simulated using sequential Gaussian simulation (SGS). Permeability (k) was modeled independently of porosity using SGS as well as simulated geostatistical indicator classes derived from measured grain size distribution curves. Retention characteristics were assigned employing Leverett …