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Hydrologic Tests at Characterization Well R-14

Description: Well R-14 is located in Ten Site Canyon and was completed at a depth of 1316 ft below ground surface (bgs) in August 2002 within unassigned pumiceous deposits located below the Puye Formation (fanglomerate). The well was constructed with two screens positioned below the regional water table. Individual static depths measured for each isolated screen after the Westbay{trademark} transducer monitoring system was installed in mid-December 2002 were nearly identical at 1177 ft bgs, suggesting only horizontal subsurface flow at this time, location, and depth. Screen 1 straddles the geologic contact between the Puye fanglomerate and unassigned pumiceous deposits. Screen 2 is located about 50 ft deeper than screen 1 and is only within the unassigned pumiceous deposits. Constant-rate, straddle-packer, injection tests were conducted at screen 2, including two short tests and one long test. The short tests were 1 minute each but at different injection rates. These short tests were used to select an appropriate injection rate for the long test. We analyzed both injection and recovery data from the long test using the Theis, Theis recovery, Theis residual-recovery, and specific capacity techniques. The Theis injection, Theis recovery, and specific capacity methods correct for partial screen penetration; however, the Theis residual-recovery method does not. The long test at screen 2 involved injection at a rate of 10.1 gallons per minute (gpm) for 68 minutes and recovery for the next 85 minutes. The Theis analysis for screen 2 gave the best fit to residual recovery data. These results suggest that the 158-ft thick deposits opposite screen 2 have a transmissivity (T) equal to or greater than 143 ft{sup 2}/day, and correspond to a horizontal hydraulic conductivity (K) of at least 0.9 ft/day. The specific capacity method yielded a T value equal to or greater than 177 ft{sup 2}/day, and a horizontal …
Date: August 1, 2004
Creator: McLin, S. & Stone, W.
Partner: UNT Libraries Government Documents Department
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Collaborative Research: Robust Climate Projections and Stochastic Stability of Dynamical Systems

Description: The project was completed along the lines of the original proposal, with additional elements arising as new results were obtained. The originally proposed three thrusts were expanded to include an additional, fourth one. (i) The e#11;ffects of stochastic perturbations on climate models have been examined at the fundamental level by using the theory of deterministic and random dynamical systems, in both #12;nite and in#12;nite dimensions. (ii) The theoretical results have been implemented #12;first on a delay-diff#11;erential equation (DDE) model of the El-Nino/Southern-Oscillation (ENSO) phenomenon. (iii) More detailed, physical aspects of model robustness have been considered, as proposed, within the stripped-down ICTP-AGCM (formerly SPEEDY) climate model. This aspect of the research has been complemented by both observational and intermediate-model aspects of mid-latitude and tropical climate. (iv) An additional thrust of the research relied on new and unexpected results of (i) and involved reduced-modeling strategies and associated prediction aspects have been tested within the team's empirical model reduction (EMR) framework. Finally, more detailed, physical aspects have been considered within the stripped-down SPEEDY climate model. The results of each of these four complementary e#11;fforts are presented in the next four sections, organized by topic and by the team members concentrating on the topic under discussion.
Date: October 13, 2011
Creator: Ghil, Michael; McWilliams, James; Neelin, J. David; Zaliapin, Ilya; Chekroun, Mickael; Kondrashov, Dmitri et al.
Partner: UNT Libraries Government Documents Department
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2012 ROCK DEFORMATION: FEEDBACK PROCESSES IN ROCK DEFORMATION GORDON RESEARCH CONFERENCE, AUGUST 19-24, 2012

Description: Topics covered include: Failure At High Confining Pressure; Fluid-assisted Slip, Earthquakes & Fracture; Reaction-driven Cracking; Fluid Transport, Deformation And Reaction; Localized Fluid Transport And Deformation; Earthquake Mechanisms; Subduction Zone Dynamics And Crustal Growth.
Date: August 24, 2012
Creator: Kelemen, Peter
Partner: UNT Libraries Government Documents Department
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Final Technical Report - Integrated Hydrogeophysical and Hydrogeologic Driven Parameter Upscaling for Dual-Domain Transport Modeling

Description: The three major components of this research were: 1. Application of minimally invasive, cost effective hydrogeophysical techniques (surface and borehole), to generate fine scale (~1m or less) 3D estimates of subsurface heterogeneity. Heterogeneity is defined as spatial variability in hydraulic conductivity and/or hydrolithologic zones. 2. Integration of the fine scale characterization of hydrogeologic parameters with the hydrogeologic facies to upscale the finer scale assessment of heterogeneity to field scale. 3. Determination of the relationship between dual-domain parameters and practical characterization data.
Date: November 5, 2012
Creator: Shafer, John M
Partner: UNT Libraries Government Documents Department
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Geomechanical Simulation of Fluid-Driven Fractures

Description: The project supported graduate students working on experimental and numerical modeling of rock fracture, with the following objectives: (a) perform laboratory testing of fluid-saturated rock; (b) develop predictive models for simulation of fracture; and (c) establish educational frameworks for geologic sequestration issues related to rock fracture. These objectives were achieved through (i) using a novel apparatus to produce faulting in a fluid-saturated rock; (ii) modeling fracture with a boundary element method; and (iii) developing curricula for training geoengineers in experimental mechanics, numerical modeling of fracture, and poroelasticity.
Date: November 30, 2012
Creator: Makhnenko, R.; Nikolskiy, D.; Mogilevskaya, S. & Labuz, J.
Partner: UNT Libraries Government Documents Department
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Probabilistic Simulation of Subsurface Fluid Flow: A Study Using a Numerical Scheme

Description: There has been an increasing interest in probabilistic modeling of hydrogeologic systems. The classical approach to groundwater modeling has been deterministic in nature, where individual layers and formations are assumed to be uniformly homogeneous. Even in the case of complex heterogeneous systems, the heterogeneities describe the differences in parameter values between various layers, but not within any individual layer. In a deterministic model a single-number is assigned to each hydrogeologic parameter, given a particular scale of interest. However, physically there is no such entity as a truly uniform and homogeneous unit. Single-number representations or deterministic predictions are subject to uncertainties. The approach used in this work models such uncertainties with probabilistic parameters. The resulting statistical distributions of output variables are analyzed. A numerical algorithm, based on axiomatic principles of probability theory, performs arithmetic operations between probability distributions. Two subroutines are developed from the algorithm and incorporated into the computer program TERZAGI, which solves groundwater flow problems in saturated, multi-dimensional systems. The probabilistic computer program is given the name, PROGRES. The algorithm has been applied to study the following problems: one-dimensional flow through homogeneous media, steady-state and transient flow conditions, one-dimensional flow through heterogeneous media, steady-state and transient flow conditions, and two-dimensional steady-stte flow through heterogeneous media. The results are compared with those available in the literature.
Date: March 1, 1980
Creator: Buscheck, Timothy Eric
Partner: UNT Libraries Government Documents Department
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MITAS-2009 Expedition, U.S. Beaufort Shelf and Slope—Lithostratigraphy Data Report

Description: The volume of methane released through the Arctic Ocean to the atmosphere and its potential role in the global climate cycle have increasingly become the focus of studies seeking to understand the source and origin of this methane. In 2009, an international, multi-disciplinary science party aboard the U.S. Coast Guard icebreaker Polar Sea successfully completed a trans-U.S. Beaufort Shelf expedition aimed at understanding the sources and volumes of methane across this region. Following more than a year of preliminary cruise planning and a thorough site evaluation, the Methane in the Arctic Shelf/Slope (MITAS) expedition departed from the waters off the coast of Barrow, Alaska in September 2009. The expedition was organized with an international shipboard science team consisting of 33 scientists with the breadth of expertise necessary to meet the expedition goals. NETL researchers led the expedition’s initial core processing and lithostratigraphic evaluations, which are the focus of this report. This data report is focused on the lithostratigraphic datasets from the recovered vibra cores and piston cores. Operational information about the piston and vibra cores such as date acquired, core name, total length, water depth, and geographic location is provided. Once recovered, gas samples were immediately collected from cores. In addition, each core was run through the Geotek multi-sensor core logger for magnetic susceptibility, P-wave velocity, resistivity, and gamma-density measurements (Rose et al., 2010). After the samples and measurements were completed, the cores were split into working and archive halves. Visual core descriptions of the archive half was completed for each core. Samples for shipboard smear slides, coarse fractions, and XRD analyses were collected, as well as corresponding samples for post-cruise grain size analysis from the working half of each core. Line scan images of the split core surfaces were collected post-expedition. The methods used to characterize the lithostratigraphy of …
Date: September 17, 2012
Creator: Rose, K.; Johnson, J.E.; Phillips, S.C.; Smith, J.; Reed, A.; Disenhof, C. et al.
Partner: UNT Libraries Government Documents Department
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ON""GENERAL CONSERVATION EQUATIONS FOR MULTIPHASE SYSTEMS: 1. AVERAGING PROCEDURE"" BY M. HASSANIZADEH AND W.G. GRAY.

Description: The author comments upon a point made in the referenced paper on general conservation equations. The author directs attention to the fact that the referenced paper's authors correctly point out that when an averaging operation involves integration, the integrand multiplied by the infinitesimal volume must be an additive quantity. The importance of this requirement is emphasized.
Date: December 1, 1979
Creator: Narasimhan, T.N.
Partner: UNT Libraries Government Documents Department
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World Surface Currents From Ship's Drift Observations

Description: Over 4 million observations of ship's drift are on file at the U.S. National Oceanographic Data Centre, in Washington, D. C., representing a vast amount of information on ocean surface currents. The observed drift speeds are dependent on the frequency of occurence of the particular current speeds and the frequency of observation. By comparing frequency of observation with the drift speeds observed it is possible to confirm known current patterns and detect singularities in surface currents.
Date: November 1, 1980
Creator: Duncan, C. P. & Schladow, S. G.
Partner: UNT Libraries Government Documents Department
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Final Report for DOE grant DE-FG02-07ER64432 "New Grid and Discretization Technologies for Ocean and Ice Simulations"

Description: The work reported is in pursuit of these goals: high-quality unstructured, non-uniform Voronoi and Delaunay grids; improved finite element and finite volume discretization schemes; and improved finite element and finite volume discretization schemes. These are sought for application to spherical and three-dimensional applications suitable for ocean, atmosphere, ice-sheet, and other climate modeling applications.
Date: March 12, 2013
Creator: Gunzburger, Max
Partner: UNT Libraries Government Documents Department
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RESULTS OF A DATING ATTEMPT -CHEMICAL AND PHYSICAL MEASUREMENTS RELEVANT TO THE CASE OF THE CRETACEOUS TERTIARY EXTINCTIONS

Description: In Gubbio, Italy, a l em layer of clay between extensive limestone formations marks the boundary between the Cretaceous and Tertiary Periods. This clay layer was known to have been deposited about 65 million years ago when many life forms became extinct, but the length of time associated with the deposition was not known. In an attempt to measure this time with normally deposited meteoritic material as a clock, extensive measurements of iridium abundances (and those of many other elements) were made on the Gubbio rocks. Neutron activation analysis was the principal tool used in these studies. About 50 elements are searched for in materials like the earth's crust, about 40 are detected and about 30 are measured with useful precision. We were not able to determine exactly how long the clay deposition took. Instead the laboratory studies on the chemical and physical nature of the Cretaceous-Tertiary boundary led to the theory that an asteroid collision with the earth was responsible for the extinction of many forms of life including the dinosaurs.
Date: September 1, 1980
Creator: Asaro, Frank; Michel, Helen V.; Alvarez, Luis W. & Alvarez, Walter
Partner: UNT Libraries Government Documents Department
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