Digital Commons Network^™

Oliver Ranch Science School Complex & Wild Horse And Burro Facility: Final Close-Out Report, Margaret N. Rees

Oliver Ranch Project

“The mission of the Red Rock Desert Learning Center is to instill stewardship and respect by increasing knowledge and understanding of the Mojave Desert ecosystems and cultures through a unique experiential discovery program.”

Precarious Rock Methodology For Seismic Hazard: Physical Testing, Numerical Modeling, And Coherence Studies, Rasool Anooshehpoor, James N. Brune, Amy J. Smiecinski, Raymond E. Keeler

Publications (YM)

The precarious rock methodology used for seismic hazard assessment includes location, age dating, field measurements of the quasi-static toppling acceleration of balanced rocks, and study of their dynamic response to realistic strong motion seismograms using numerical modeling. The work scope is contained in the task description issued by the DOE to the Seismology Laboratory of the University of Nevada, Reno and is itemized in section 2.3 below. In addition, measurement of the coherence of seismic energy at high frequencies, critical to the understanding of the variability of high frequency ground motions at the repository level, will be estimated based on …

Precarious Rock Methodology For Seismic Hazard: Physical Testing, Numerical Modeling And Coherence Studies, Rasool Anooshehpoor, Matthew D. Purvance, James N. Brune, Leiph A. Preston, John G. Anderson, Ken Smith, Amy J. Smiecinski

Publications (YM)

This report covers the following projects: Shake table tests of precarious rock methodology, field tests of precarious rocks at Yucca Mountain and comparison of the results with PSHA predictions, study of the coherence of the wave field in the ESF, and a limited survey of precarious rocks south of the proposed repository footprint. A series of shake table experiments have been carried out at the University of Nevada, Reno Large Scale Structures Laboratory. The bulk of the experiments involved scaling acceleration time histories (uniaxial forcing) from 0.1g to the point where the objects on the shake table overturned a specified …

Evidence Of An Active Enso And Pdq During The Mid-Holocene From A Costa Rican Speleothem, April D. Azouz

UNLV Theses, Dissertations, Professional Papers, and Capstones

Although the El Nino/Southern Oscillation (ENSO) is the most important source of inter-annual climate variability in the tropics, its Holocene history is poorly understood, particularly in Central America. A high resolution (-3.8 years/sample) paleoclimate record of Central American rainfall variability has been reconstructed from a U /Th-dated stalagmite (7890 to 6490 yrs B.P.) from Costa Rica to constrain the onset and variability of ENSO throughout the Holocene, and to determine its role in generating regional climate anomalies. I suggest drier conditions, forced by El Nino, are represented by higher 5180 values, and are correlative with higher 513C values, indicating that …

Extreme Ground Motion Studies, John G. Anderson, James N. Brune, Amy J. Smiecinski, Raymond E. Keeler

Publications (YM)

This project consists of two separate investigations into extreme ground motions due to seismic events. First, it includes field studies of geological formations that should put an upper bound on extreme ground motions that have happened at the site of the formations. The locations are critically selected to provide the most effective constraints possible on the validity of the probabilistic seismic hazard analysis for Yucca Mountain. Second, this project surveys recorded ground motions from around the world, and aims to draw general conclusions from these as to the conditions where extreme ground motions are observed.

Unlv Magazine, Carol C. Harter, Karen Sharp, Gian Galassi, Tony Allen, Jennifer Lawson, Shane Bevell, Lori Bachand, Regina Vaccari, Pete Codella, Cate Weeks, Erin O'Donnell, Diane Russell, Phil Hagen

UNLV Magazine

No abstract provided.

Petrogenesis Of Pleistocene Basalts In The Norris-Mammoth Corridor, Yellowstone National Park, Kristeen Marie Bennett

UNLV Theses, Dissertations, Professional Papers, and Capstones

The basalts of the Norris-Mammoth corridor within the Yellowstone Plateau volcanic field have an outcrop erupted volume of ~94 km³. Basalt in the Yellowstone Plateau volcanic field is minor in volume compared to 3,700 km³ of felsic lavas, domes, and pyroclastic rocks. The tholeiitic eruptive products formed small Hawaiian-style shield volcanoes. A newly identified volcanic vent, called the Panther Creek vent, within the Swan Lake Flat basalt stratigraphic unit, was primarily Strombolian in its eruption style. This vent is the first recognized cinder cone in Yellowstone National Park.

All basaltic units within the Norris-Mammoth corridor, and the …

Geostatistical And Stochastic Study Of Radio Nuclide Transport In The Unsaturated Zone At Yucca Mountain, Ming Ye, Amy J. Smiecinski, Raymond E. Keeler

Publications (YM)

The U.S. Nuclear Waste Technical Review Board [Cohon et al. 1998] evaluated the technical and scientific validity of activities undertaken by the Secretary of Energy to characterize Yucca Mountain, Nevada, for its suitability as an underground repository in which to store high-level radioactive waste and spent nuclear fuel. In the report, the Board pinpointed that the study on groundwater flow and radionuclide transport in the saturated and unsaturated zones below Yucca Mountain should, over the next several years, focus on reducing prediction uncertainty. In its 2002, the Board repeated this concern by stating, “… hydrogeologic processes that affect radionuclide transport …

Unlv Magazine, Carol C. Harter, Joe Cockrell, Tony Allen, Regina Bacolas, Lori Bachand, Jennifer Lawson, Bret C. Birdsong, Steve Parker, Erin O'Donnell, Jennifer Robison

UNLV Magazine

No abstract provided.

Long-Term Mechanical Behavior Of Yucca Mountain Tuff And Its Variability, Jaak J.K. Daemen, Lumin Ma, Guohua Zhao

Publications (YM)

The study of the long term mechanical behavior of Yucca Mountain tuffs is important for several reasons. Long term stability of excavations will affect accessibility (e.g. for inspection purposes), and retrievability. Long term instabilities may induce loading of drip shields and/or emplaced waste, thus affecting drip shield and/or waste package corrosion. Failure of excavations will affect airflow, may affect water flow, and may affect temperature distributions.

The long term mechanical behavior of “hard” rocks remains an elusive topic, loaded with uncertainties. A variety of approaches have been used to improve the understanding of this complex subject, but it is doubtful …

Results Of Chemical Analyses For Alcove 8/ Niche 3 Tracer Studies, Jeanette Daniels, Amy J. Smiecinski

Publications (YM)

This is the final report detailing the analyses performed under ORD-FY04-011 "Chemical Analyses for Alcove 8/Niche 3 Tracer Studies," The work was performed under The University and Community College System of Nevada (UCCSN) and the Department of Energy (DOE) Cooperative Agreement DE-FC28-04RW12232, This task provided method development and analytical support for the Alcove 8/Niche 3 Tracer Studies in the Exploratory Studies Facility (ESF). Concentrations of tracers as well as major anions and cations were reported for samples provided by Lawrence Berkeley National Laboratory (LBNL) and the US Geological Survey (USGS). Samples were analyzed using High Performance Liquid Chromatography (HPLC) and …

Determining The Redox Properties Of Yucca Mountain-Related Groundwater Using Trace Element Speciation For Predicting The Mobility Of Nuclear Waste, James Cizdziel, Amy J. Smiecinski

Publications (YM)

The objective of this task is to determine the principal oxidation state (redox) species of select elements in samples of groundwater in the vicinity of Yucca Mountain (YM), which is being evaluated as a site for geologic storage of the nation’s spent nuclear fuel and high-level nuclear waste. Samples to be analyzed include, but are not limited to, groundwater from wells of the Nye County Early Warning Drilling Program. Elements to be studied include arsenic (As), antimony (Sb), selenium (Se), chromium (Cr), manganese (Mn), iron (Fe), copper (Cu), molybdenum (Mo), vanadium (V), tungsten (W), rhenium (Re), and uranium (U). The …

Canopy-Tree Influences Along A Soil Parent Material Gradient In Pinus-Ponderosa-Quercus Gambelii Forests, Northern Arizona, Scott R. Abella, Judith D. Springer

Public Policy and Leadership Faculty Publications

ABELLA, S. R. (Public Lands Institute and School of Life Sciences, University of Nevada, Las Vegas, Las Vegas, NV 89154-2040) AND J. D. SPRINGER (Ecological Restoration Institute, Northern Arizona University, Flagstaff, AZ 86011-5017). Canopy-tree influences along a soil parent material gradient in Pinus ponderosa- Quercus gambelii forests, northern Arizona. J. Torrey Bot. Soc. 135: 26–36. 2008.—The distribution of canopy trees can impose within-site patterns of soil properties and understory plant composition. At ten sites spanning a soil parent material gradient in northern Arizona Pinus ponderosa-Quercus gambelii forests, we compared soils and plant composition among five canopy types: openings, Pinus ponderosa …

Bomb-Pulse Chlorine-36 At The Proposed Yucca Mountain Repository Horizon: An Investigation Of Previous Conflicting Results And Collection Of New Data, James Cizdziel, Amy J. Smiecinski

Publications (YM)

Previous studies by scientists at Los Alamos National Laboratory (LANL) found elevated ratios of chlorine-36 to total chloride (36C1/C1) in samples of rock collected from the Exploratory Studies Facility (ESF) and the Enhanced Characterization of the Repository Block (ECRB) at Yucca Mountain as the tunnels were excavated. The data were interpreted as an indication that fluids containing "bomb-pulse" 36C1 reached the repository horizon in the -50 years since the peak period of above-ground nuclear testing. Moreover, the data support the concept that so-called fast pathways for infiltration not only exist but are active, possibly through a combination of porous media, …