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A scoping study of water table excursions induced by seismic and volcanic events

Description: We develop conservative models of water table response to displacements just beneath the water table simulating (1) shallow intrusion of a dike and (2) high level slip on a normal fault locked at the end. For matrix flow, we fine local water table excursions of under 10 m. in cases of isotropic permeability which includes dike inflation of 4 m and fault slips corresponding to earthquakes having a moment magnitude of 7.4. Even for enhancements of vertical permeability up to 10{sup 4}:1, excursions did not exceed 15 m which implies that pumping is strongly volume limited. We also present an analysis of upward directed flow in cracks for the case of earthquake induced pore pressure changes. For matrix properties characteristic of the Calico Hills (vitric) formation and a crack distribution bounding the potential flow capacity of published data, we estimate an upper bound of 0.25 cu m. of ground water per m. of fault length as the amount capable of being pumped to a level 250 m. above the normal water table. While the presence of even larger fractures than assumed might carry more ground water to that level an absolute upper limit of less than 50 cu. m. per m. of fault length is available to be pumped assuming a value n=0.46 for the rock porosity. For less porous rocks typical of the Topopah Spring or Tiva Canyon formations (n{approx}0.10) the upper limit may be reduced to less than 10 cu. m. per m. of fault length. This upper limit depends only upon strain, the height of pumping above the water table and the formation porosity.
Date: November 1, 1990
Creator: Carrigan, C.R.; King, G.C.P. & Barr, G.E.
Partner: UNT Libraries Government Documents Department

Haze in the Grand Canyon: An evaluation of the Winter Haze Intensive Tracer Experiment

Description: The Grand Canyon is one of the most spectacular natural sights on earth. Approximately 4 million visitors travel to Grand Canyon National Park (GCNP) each year to enjoy its majestic geological formations and intensely colored views. However, visibility in GCNP can be impaired by small increases in concentrations of fine suspended particles that scatter and absorb light; the resulting visibility degradation is perceived as haze. Sulfate particles are a major factor in visibility impairment at Grand Canyon in summer and winter. Many wintertime hazes at GCNP are believed to result from the accumulation of emissions from local sources during conditions of air stagnation, which occur more frequently in winter than in summer. In January and February 1987, the National Park Service (NPS) carried out a large-scale experiment known as the Winter Haze Intensive Tracer Experiment (WHITEX) to investigate the causes of wintertime haze in the region of GCNP and Canyonlands National Park. The overall objective of WHITEX was to assess the feasibility of attributing visibility impairment in specific geographic regions to emissions from a single point source. The experiment called for the injection of a tracer, deuterated methane (CD{sub 4}), into one of the stacks of the Navajo Generating Station (NGS), a major coal-fired power plant located 25 km from the GCNP boundary and 110 km northeast of Grand Canyon Village. A network of field stations was established in the vicinity -- mostly to the northeast of GCNP and NGS -- to measure CD{sub 4} concentrations, atmospheric aerosol and optical properties, and other chemical and physical attributes. 19 refs., 3 figs.
Date: October 1, 1990
Partner: UNT Libraries Government Documents Department

Hot nuclei -- Landau theory, thermal fluctuations and dissipation

Description: The basic ideas and theoretical methods used in the description of hot nuclei are reviewed. In particular, a macroscopic approach to shape transitions is discussed in the framework of the Landau theory in which the quadrupole shape degrees of freedom play the role of the order parameters. This theory describes the universal features of the nuclear shape evolution with temperature and spin. A unified description of fluctuations in all five quadrupole degrees of freedom is introduced and plays an important role in the calculation of physical observables. A macroscopic approach to the giant dipole resonance (GDR) in hot nuclei is developed. With all parameters fixed by the zero temperature nuclear properties, the theory predicts both the GDR cross-section and angular anisotropy of the {gamma}-rays in very good agreement with recent experiments. The intrinsic shape fluctuations are the main cause for the resonance broadening at higher temperatures, while the orientation fluctuations are responsible for the observed attenuation in the angular anisotropy. Dissipation at finite temperature is discussed in the framework of a Langevin-like equation describing the time-dependent shape fluctuations. Non-adiabatic effects may cause motional narrowing of the resonance.
Date: January 1, 1990
Creator: Alhassid, Y.
Partner: UNT Libraries Government Documents Department

Classification of hydrostratigraphic units at the Savannah River Site, South Carolina

Description: A detailed synthesis of the hydrologic, geophysical and core data from wells penetrating the updip Mesozoic-Cenozoic Coastal Plain sequence at and near the Savannah River Site (SRS) was conducted to define and classify the hydrostratigraphic units. The purpose of the study was to give the SRS a single unified hydrostratigraphic classification that defines and addresses the hydrogeologic characteristics of the aquifers underlying the site. The characterization, areal distribution and classification of the aquifer and aquifer systems gives SRS the tools to evaluate ground water movement and contaminant transport in a comprehensive regional context. An alpha-numeric nomenclature has been temporarily adopted in this report for classifying the aquifers and aquifer systems at SRS. Formal geographic names for the aquifers and aquifer systems will be proposed in the near future but must be agreed upon and ratified by the South Carolina Hydrostratigraphic Subcommittee which was in part organized for the purpose. The classification utilizes a hierarchy of terms ranked at three levels: Aquifer Systems that transmit ground water regionally; Aquifer Units which are mappable units > 400 square miles in area; and Aquifer Zones that differentiate aquifers internally on the basis of locally significant characteristics.
Date: December 1, 1990
Creator: Aadland, R.K. & Bledsoe, H.W.
Partner: UNT Libraries Government Documents Department

Kootenai River Wildlife Habitat Enhancement Project : Long-term Bighorn Sheep/Mule Deer Winter and Spring Habitat Improvement Project : Wildlife Mitigation Project, Libby Dam, Montana : Management Plan.

Description: The Libby hydroelectric project, located on the Kootenai River in northwestern Montana, resulted in several impacts to the wildlife communities which occupied the habitats inundated by Lake Koocanusa. Montana Department of Fish, Wildlife and Parks, in cooperation with the other management agencies, developed an impact assessment and a wildlife and wildlife habitat mitigation plan for the Libby hydroelectric facility. In response to the mitigation plan, Bonneville Power Administration funded a cooperative project between the Kootenai National Forest and Montana Department of Fish, Wildlife and Parks to develop a long-term habitat enhancement plan for the bighorn sheep and mule deer winter and spring ranges adjacent to Lake Koocanusa. The project goal is to rehabilitate 3372 acres of bighorn sheep and 16,321 acres of mule deer winter and spring ranges on Kootenai National Forest lands adjacent to Lake Koocanusa and to monitor and evaluate the effects of implementing this habitat enhancement work. 2 refs.
Date: June 1, 1990
Creator: Yde, Chis
Partner: UNT Libraries Government Documents Department

Japanese power electronics inverter technology and its impact on the American air conditioning industry

Description: Since 1983, technological advances and market growth of inverter- driven variable-speed heat pumps in Japan have been dramatic. The high level of market penetration was promoted by a combination of political, economic, and trade policies in Japan. A unique environment was created in which the leading domestic industries-- microprocessor manufacturing, compressors for air conditioning and refrigerators, and power electronic devices--were able to direct the development and market success of inverter-driven heat pumps. As a result, leading US variable-speed heat pump manufacturers should expect a challenge from the Japanese producers of power devices and microprocessors. Because of the vertically-integrated production structure in Japan, in contrast to the out-sourcing culture of the United States, price competition at the component level (such as inverters, sensors, and controls) may impact the structure of the industry more severely than final product sales. 54 refs., 47 figs., 1 tab.
Date: August 1, 1990
Creator: Ushimaru, Kenji.
Partner: UNT Libraries Government Documents Department

Stability and performance of CDRL-FEL (Chemical Dynamics Research Laboratory-Free Electron Laser)

Description: We study the performance of a proposed infrared free electron laser at Lawrence Berkeley Laboratory, which would be a user facility and therefore has a unique set of requirements in intensity, spectrum and stability. The output performance in intensity and spectrum, and methods to optimize the performance, are studied in detail. The effect of the electron beam fluctuation on FEL stability is carefully evaluated to set a tolerance for the accelerator design. Use of intracavity gratings is studied as a means of further improving the spectral purity and stability. 19 refs., 12 figs., 2 tabs.
Date: November 1, 1990
Creator: Kim, K.J. & Xie, M.
Partner: UNT Libraries Government Documents Department

A kinetic theory of trapped electron driven drift wave turbulence in a sheared magnetic field

Description: A kinetic theory of collisionless and dissipative trapped electron driven drift wave turbulence in a sheared magnetic field is presented. Weak turbulence theory is employed to calculate the nonlinear electron and ion responses and to derive a wave kinetic equation that determines the nonlinear evolution of trapped electron mode turbulence. Saturated fluctuation spectrum is calculated using the condition of nonlinear saturation. The turbulent transport coefficients are in turn calculated using saturated fluctuation spectrum. Due to the disparity in the three different radial scale lengths of the slab-like eigenmode: {Delta} (trapped electron layer width), x{sub t} (turning point width) and x{sub i} (Landau damping point), {Delta} < x{sub t} < x{sub i}, we find that ion Compton scattering rather than trapped electron Compton scattering is the dominant nonlinear saturation mechanism. Ion Compton scattering transfers wave energy from short to long wavelengths where the wave energy is shear damped. As a consequence, a saturated fluctuation spectrum {vert bar}{phi}{vert bar}{sup 2}(k{sub {theta}}) {approximately} k{sub {theta}}{sup {minus}{alpha}} ({alpha} = 2 and 3 for the dissipative and collisionless regime, respectively) occurs for k{sub {theta}}{rho}{sub s} < 1 and is heavily damped for k{sub {theta}}{rho}{sub s} > 1. The predicted fluctuation level and transport coefficients are well below the mixing length'' estimate. This is due to the contribution of radial wavenumbers x{sub t}{sup {minus}1} < k{sub r} {le} {rho}{sub i}{sup {minus}1} to the nonlinear couplings, the effect of radial localization of trapped electron response to a layer of width, {Delta}, and the weak turbulence factor {l angle}({gamma}{sub e}{sup l})/({omega}{sub {rvec {kappa}}}){r angle}{sub {rvec k}} < 1, which enters the saturation level. 18 refs., 1 tab.
Date: September 1, 1990
Creator: Gang, F.Y. (Texas Univ., Austin, TX (USA). Inst. for Fusion Studies); Diamond, P.H. & Rosenbluth, M.N. (California Univ., San Diego, La Jolla, CA (USA). Dept. of Physics General Atomics, San Diego, CA (USA))
Partner: UNT Libraries Government Documents Department

Review of recent stellarator results in the USA, the USSR, and Japan

Description: Stellarators with significant magnetic shear in the United States, the Soviet Union, and Japan are described, and recent results are discussed in terms of their contributions to the physics understanding relevant for stellarator optimization and to toroidal confinement understanding in general. The areas discussed are the properties of stellarators with significant shear, magnetic surfaces, trapped-particle losses, magnetohydrodynamic (MHD) stability, global confinement scaling, local transport, fluctuations, and particle and impurity control. 58 refs., 23 figs.
Date: December 1, 1990
Creator: Lyon, J.F.
Partner: UNT Libraries Government Documents Department

Far infrared fusion plasma diagnostics

Description: Over the last several years, reflectometry has grown in importance as a diagnostic for both steady-state density Profiles as well as for the investigation of density fluctuations and turbulence. As a diagnostic for density profile measurement, it is generally believed to be well understood in the tokamak environment. However, its use as a fluctuation diagnostic is hampered by a lack of quantitative experimental understanding of its wavenumber sensitivity and spatial resolution. Several researchers, have theoretically investigated these questions. However, prior to the UCLA laboratory investigation, no group has experimentally investigated these questions. Because of the reflectometer's importance to the world effort in understanding plasma turbulence and transport, UCLA has, over the last year, made its primary Task IIIA effort the resolution of these questions. UCLA has taken the lead in a quantitative experimental understanding of reflectometer data as applied to the measurement of density fluctuations. In addition to this, work has proceeded on the design, construction, and installation of a reflectometer system on UCLA's CCT tokamak. This effort will allow a comparison between the improved confinement regimes (H-mode) observed on both the DIII-D and CCT machines with the goal of achieving a physics understanding of the phenomena. Preliminary investigation of a new diagnostic technique to measure density profiles as a function of time has been initiated at UCLA. The technique promises to be a valuable addition to the range of available plasma diagnostics. Work on advanced holographic reflectometry technique as applied to fluctuation diagnostics has awaited a better understanding of the reflectometer signal itself as discussed above. Efforts to ensure the transfer of the diagnostic developments have continued with particular attention devoted to the preliminary design of a multichannel FIR interferometer for MST.
Date: January 1, 1990
Creator: Luhmann, N.C. Jr. & Peebles, W.A.
Partner: UNT Libraries Government Documents Department

Laboratory analysis of fluid flow and solute transport through a variably saturated fracture embedded in porous tuff

Description: Laboratory techniques are developed that allow concurrent measurement of unsaturated matrix hydraulic conductivity and fracture transmissivity of fractured rock blocks. Two Apache Leap tuff blocks with natural fractures were removed from near Superior, Arizona, shaped into rectangular prisms, and instrumented in the laboratory. Porous ceramic plates provided solution to block tops at regulated pressures. Infiltration tests were performed on both test blocks. Steady flow testing of the saturated first block provided estimates of matrix hydraulic conductivity and fracture transmissivity. Fifteen centimeters of suction applied to the second block top showed that fracture flow was minimal and matrix hydraulic conductivity was an order of magnitude less than the first block saturated matrix conductivity. Coated-wire ion-selective electrodes monitored aqueous chlorided breakthrough concentrations. Minute samples of tracer solution were collected with filter paper. The techniques worked well for studying transport behavior at near-saturated flow conditions and also appear to be promising for unsaturated conditions. Breakthrough curves in the fracture and matrix, and a concentration map of chloride concentrations within the fracture, suggest preferential flows paths in the fracture and substantial diffusion into the matrix. Average travel velocity, dispersion coefficient and longitudinal dispersivity in the fracture are obtained. 67 refs., 54 figs., 23 tabs.
Date: February 1, 1990
Creator: Chuang, Y.; Haldeman, W.R.; Rasmussen, T.C. & Evans, D.D.
Partner: UNT Libraries Government Documents Department

Report of the committee to review the use of J-13 well water in Nevada Nuclear Waste Storage Investigations

Description: The Waste Management Project Office of the Department of Energy conducted a special audit of the activities of the Nevada Nuclear Waste Storage Investigation Project at Livermore. It was noted that there never has been a comprehensive, well-documented examination of the basis for the use of J-13 water in the nuclear waste storage investigations. In each of the sections of This Report, an issue relating to the use of J-13 water has been addressed. 58 refs., 19 figs., 8 tabs.
Date: January 1, 1990
Creator: Harrar, J.E.; Carley, J.F.; Isherwood, W.F. & Raber, E.
Partner: UNT Libraries Government Documents Department

Comparisons of model simulations of climate variability with data, Task 2

Description: Significant progress has been made in our investigations aimed at diagnosing low frequency variations of climate in General Circulation Models. We have analyzed three versions of the Oregon State University General Circulation Model (OSU GCM). These are: (1) the Slab Model in which the ocean is treated as a static heat reservoir of fixed depth, (2) the coupled upper ocean-atmosphere model in which the ocean dynamics are calculated in two layers of variable depths representing the mixed layers and the thermocline; this model is referred to OSU2 in the following discussion, and (3) the coupled full ocean-atmosphere model in which the ocean is represented by six layers of variable depth; this model is referred to as OSU6 GCM in the discussion.
Date: January 1, 1990
Partner: UNT Libraries Government Documents Department

Apportionment of multiple aerosol size distributions modes using factor analysis techniques

Description: This research in progress is concerned with developing the capability to ojectively partition aerosol size distribution data into a small number of modes, that together explain most of the variation of the observed data. It is desired to determine from analysis in the field of the optical spectrometer data when a particular mode is present and to collect filter samples to determine the chemical composition of that mode. The results would relate aerosol size distributions to chemical composition.
Date: December 31, 1990
Creator: Williams, Allen
Partner: UNT Libraries Government Documents Department

Insolation data manual and direct normal solar radiation data manual

Description: The Insolation Data Manual presents monthly averaged data which describes the availability of solar radiation at 248 National Weather Service (NWS) stations, principally in the United States. Monthly and annual average daily insolation and temperature values have been computed from a base of 24--25 years of data, generally from 1952--1975, and listed for each location. Insolation values represent monthly average daily totals of global radiation on a horizontal surface and are depicted using the three units of measurement: kJ/m{sup 2} per day, Btu/ft{sup 2} per day and langleys per day. Average daily maximum, minimum and monthly temperatures are provided for most locations in both Celsius and Fahrenheit. Heating and cooling degree-days were computed relative to a base of 18.3 C (65 F). For each station, global {bar K}{sub T} (cloudiness index) values were calculated on a monthly and annual basis. Global {bar K}{sub T} is an index of cloudiness and indicates fractional transmittance of horizontal radiation, from the top of the atmosphere to the earth's surface. The second section of this volume presents long-term monthly and annual averages of direct normal solar radiation for 235 NWS stations, including a discussion of the basic derivation process. This effort is in response to a generally recognized need for reliable direct normal data and the recent availability of 23 years of hourly averages for 235 stations. The relative inaccessibility of these data on microfiche further justifies reproducing at least the long-term averages in a useful format. In addition to a definition of terms and an overview of the ADIPA model, a discussion of model validation results is presented.
Date: July 1, 1990
Partner: UNT Libraries Government Documents Department

Response of mosquitofish (Gambusia affinis) populations to seasonally unpredictable perturbations

Description: Many questions remain unresolved about the linkages between life history attributes of fishes and the tactics that these organisms employ in response to environmental uncertainty. Such questions include (1). If a perturbation affects the entire ecosystem, what are the consequences for a given population of fish (2) What tactics can a fish employ to increase its chances of leaving offspring (3) Do fish respond differently to such perturbations depending on the season (4) How do these changes relate to the overall resilience of the population The research reported here was designed to address such questions. Mosquito fish (Gambusia affinis) populations in thirteen experimental ponds at Oak Ridge National Laboratory were sampled ten times between June 1988, and July 1989 in response to a series of chemical disturbances. During each sampling period the population size and total biomass of Gambusia in each pond was estimated using photographs and a length weight regression. Size-frequency histograms were used to examine seasonal and dose-related changes in population structure. Lipid content and reproductive allotment were measured for a series of fish from each pond on all dates to explore the energy allocation patterns at the individual. 106 refs., 38 figs., 16 tabs.
Date: July 1, 1990
Creator: Horn, M.J. & Stewart, A.J.
Partner: UNT Libraries Government Documents Department

ATF (Advanced Toroidal Facility) edge plasma turbulence studies using a fast reciprocating Langmuir probe

Description: Electrostatic turbulence on the edge of the Advanced Torodial Facility (ATF) torsatron is investigated experimentally with a fast reciprocating Langmuir probe (FRLP) array. Initial measurements of plasma electron density n{sub e} and temperature T{sub e} and fluctuations in density ({tilde n}{sub e}) and plasma floating potential ({tilde {phi}}{sub f}) are made in ECH plasmas at 1 T. At the last closed flux surface (LCFS, r/{bar a} {approximately}1), T{sub e} {approx} 20--40 eV and n{sub e} {approx} 10{sup 12} cm{sup {minus}3} for a line-averaged electron density {bar n}{sub e} = (3--6) {times} 10{sup 12} cm{sup {minus}3}. Relative fluctuation levels, as the FRLP is moved into core plasma where T{sub e} > 20 eV, are {tilde n}{sub e}/n{sub e} {approx} 5%, and e {tilde {phi}}{sub f}/T{sub e} {approx} 2{tilde n}{sub e}/n{sub e} about 2 cm inside the LCFS. The observed fluctuation spectra are broadband (40--300 kHz) with {bar k}{rho}{sub s} {le} 0.1, where {bar k} is the wavenumber of the fluctuations and {rho}{sub s} is the ion Larmor radius at the sound speed. The propagation direction of the fluctuations reverses to the electron diamagnetic direction around r/{bar a} < 1. The phase velocity and the electron drift velocity are comparable (v{sub ph} {approximately} v{sub de}). The fluctuation-induced particle flux is comparable to fluxes estimated from the particle balance using the H{sub {alpha}} spectroscopic measurements. Many of the features seen in these experiments resemble the features of ohmically heated plasmas in the Texas Experimental Tokamak (TEXT). 17 refs., 10 figs.
Date: January 1, 1990
Creator: Uckan, T.; Hidalgo, C.; Bell, J.D.; Harris, J.H.; Dunlap, J.L.; Dyer, G.R. et al.
Partner: UNT Libraries Government Documents Department