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Project Final Report Regional Forest-ABL Coupling: Influence on CO2 and Climate

Description: Ecosystem CO{sub 2} exchange and atmospheric boundary layer (ABL) mixing are correlated diurnally and seasonally. Tracer transport models predict that these covariance signals produce a meridional gradient of annual mean CO{sub 2} concentration in the marine boundary layer that is half as strong as the signal produced by fossil fuel emissions. This rectifier effect has been predicted by many inversion models. However, observations to constrain the strength of the rectifier effect in nature are … more
Date: April 2, 2003
Creator: Davis, Kenneth J. & Yi, Chuixiang
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The effect of CO2(aq), Al(aq) and temperature on feldspar dissolution

Description: The authors measured labradorite (Ca{sub 0.6}Na{sub 0.4}Al{sub 1.6}Si{sub 2.4}O{sub 8}) dissolution rates using a mixed flow reactor from 30 to 130 C as a function of CO{sub 2} (3 x 10{sup -3} and 0.6 M), and aluminum (10{sup -6} to 10{sup -3}M) at pH 3.2. Over these conditions, labradorite dissolution can be described with a single rate expression that accounts for observed increases in dissolution rate with temperature and decreases in dissolution rate with dissolved aluminum: Rate{sub Si} (m… more
Date: October 14, 2003
Creator: Carroll, S. & Knauss, K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Inversion of Synthetic Aperture Radar Interferograms for Sources of Production-Related Subsidence at the Dixie Valley Geothermal Field

Description: We used synthetic aperture radar interferograms to image ground subsidence that occurred over the Dixie Valley geothermal field during different time intervals between 1992 and 1997. Linear elastic inversion of the subsidence that occurred between April, 1996 and March, 1997 revealed that the dominant sources of deformation during this time period were large changes in fluid volumes at shallow depths within the valley fill above the reservoir. The distributions of subsidence and subsurface volu… more
Date: February 7, 2003
Creator: Foxall, W & Vasco, D
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A CHRONOLOGICAL FRAMEWORK FOR THE HOLOCENE VEGETATIONAL HISTORY OF CENTRAL MINNESOTA: THE STEEL LAKE POLLEN RECORD

Description: Paleorecords from Minnesota and adjacent areas have often been used to evaluate large-scale climatic processes in the mid-continent of North America. However, most of these records are compromised by chronological flaws, making problematic any comparisons with climatic interpretations based on other records (e.g., GISP2 in Greenland). We report here a high-resolution pollen record with a secure chronology constrained by 26 {sup 14}C dates on terrestrial macrofossils from Steel Lake, central Min… more
Date: November 10, 2003
Creator: Wright, H E; Stefanova, I; Tian, J; Brown, T A & Hu, F S
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Comparison of up-scaling methods in poroelasticity and its generalizations

Description: Four methods of up-scaling coupled equations at the microscale to equations valid at the mesoscale and/or macroscale for fluid-saturated and partially saturated porous media will be discussed, compared, and contrasted. The four methods are: (1) effective medium theory, (2) mixture theory, (3) two-scale and multiscale homogenization, and (4) volume averaging. All these methods have advantages for some applications and disadvantages for others. For example, effective medium theory, mixture theory… more
Date: December 13, 2003
Creator: Berger, E. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Moment Magnitude Calibration for the Eastern Mediterranean Region from Broadband Regional Coda Envelopes

Description: The following is an overview of results from ROA01-32 that focuses on an empirical method of calibrating stable seismic source moment-rate spectra derived from regional coda envelopes using broadband stations. The main goal was to develop a regional magnitude methodology that had the following properties: (1) it is tied to an absolute scale and is thus unbiased and transportable; (2) it can be tied seamlessly to the well-established teleseismic and regional catalogs; (3) it is applicable to sma… more
Date: July 17, 2003
Creator: Mayeda, K; Eken, T; Hofstetter, A; Turkelli, N; O'Boyle, J; Orgulu, G et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Regional Body-Wave Corrections and Surface-Wave Tomography Models to Improve Discrimination

Description: Our identification research for the past several years has focused on the problem of correctly discriminating small-magnitude explosions from a background of earthquakes, mining tremors, and other events. Small magnitudes lead to an emphasis on regional waveforms. The goal is to reduce the variance within the population of each type of event, while increasing the separation between the explosions and the other event types. We address this problem for both broad categories of seismic waves, body… more
Date: July 18, 2003
Creator: Walter, W R; Pasyanos, M E; Rodgers, A J; Meyeda, K M & Sicherman, A
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Developing Smart Seismic Arrays: A Simulation Environment, Observational Database, and Advanced Signal Processing

Description: Seismic imaging and tracking methods have intelligence and monitoring applications. Current systems, however, do not adequately calibrate or model the unknown geological heterogeneity. Current systems are also not designed for rapid data acquisition and analysis in the field. This project seeks to build the core technological capabilities coupled with innovative deployment, processing, and analysis methodologies to allow seismic methods to be effectively utilized in the applications of seismic … more
Date: September 15, 2003
Creator: Harben, P E; Harris, D; Myers, S; Larsen, S; Wagoner, J; Trebes, J et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Evaluation of the Relative Importance of Parameters Influencing Perforation Cleanup

Description: Completion of cased and cemented wells by shaped-charge perforation results in damage to the formation, which can significantly reduce well productivity. Typically, underbalanced conditions are imposed during perforation in an effort to remove damaged rock and shaped-charge debris from the perforation tunnel. Immediately after the shaped-charge jet penetrates the formation, there is a transient surge of fluid from the formation through the perforation and into the well bore. Experimental eviden… more
Date: October 22, 2003
Creator: Detwiler, R L; Morris, J P; Karacan, C O; Halleck, P M & Hardesty, J
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Calibration of Regional Seismic Stations in the Middle East with Shots in Turkey

Description: The objective of this project is to calibrate regional travel-times and propagation characteristics of seismic waves in Turkey and surrounding areas in the Middle East in order to enhance detection and location capabilities in the region. Important data for the project will be obtained by large calibration shots in central and eastern Turkey. The first, a two-ton shot, was fired in boreholes near Keskin in central Anatolia on 23 November 2002. The explosives were placed in 14 holes, each 80 m d… more
Date: July 21, 2003
Creator: Toksoz, M N; Kuleli, S; Gurbuz, C; Kalafat, D; Nekler, T; Zor, K et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Second Quarter Hanford Seismic Report for Fiscal Year 2003

Description: This describes the earthquakes that occurred on and near the Hanford Site during the second quarter of FY03. Hanford Seismic Monitoring provides an uninterrupted collection of high-quality raw and processed seismic data from the Hanford Seismic Network for the U.S. Department of Energy and its contractors. Hanford Seismic Monitoring also locates and identifies sources of seismic activity and monitors changes in the historical pattern of seismic activity at the Hanford Site. The data are compile… more
Date: April 16, 2003
Creator: Hartshorn, Donald C.; Reidel, Steve P. & Rohay, Alan C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Estimating the Deformability and Strength of Rock Masses - In-Situ Tests, and Related Procedures

Description: This report was prepared for presentation at the STRATCOM Advanced Concept Technology Demonstration (ACTD) meeting held in Albuquerque, New Mexico, May 21, 2003. It discusses the methods that can be used to estimate the mechanical properties of rock masses, such as deformability and strength. Special emphasis is put on the fact that rock mass properties are subject to an effect of scale, i.e. the properties measured on laboratory-scale samples are not representative of in-situ properties becaus… more
Date: June 1, 2003
Creator: Heuze, F E
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Improving the Fundamental Understanding of Regional Seismic Signal Processing with a Unique Western U.S. Dataset

Description: This project has built a unique historic database of regional distance nuclear explosion, earthquake, and mine-related digital broadband seismograms for the western United States (US). The emphasis is on data from Lawrence Livermore National Laboratory (LLNL)-managed stations MNA, ELK, KNB and LAC that recorded many nuclear tests and nearby earthquakes in broadband digital form since 1980, along with a small number of earlier events that were digitized from tapes. Through the generous cooperati… more
Date: July 18, 2003
Creator: Walter, W. R.; Smith, K.; O'Boyle, J.; Hauk, T. F.; Ryall, F.; Ruppert, S. D. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Elastic modeling and steep dips: unraveling the reflected wavefield

Description: As part of a larger elastic numerical modeling project, we have been investigating how energy reflected from steeply dipping interfaces is recorded using typical multicomponent acquisition geometries. Specifically, we have been interpreting how rcflection events from the flanks of salt dome structures are distributed on 3C and 4C phones for vertical seismic profiles (VSPs) and ocean bottom seismic (OBS) or land surface surveys. The ultimate goal of this investigation is to improve the structura… more
Date: January 1, 2003
Creator: Hoelting, C. J. (Cory J.); Gherasim, M. (Mariana); House, L. S. (Leigh S.) & Marfurt, K. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Use of an ultrasonic/sonic driller/corer to obtain sample powder for chemin, a combined XRD/XRF instrument.

Description: One of the technical issues that must be addressed before landing an XRD,iXRF spectrometer on an extraterrestrial body is how best to obtain a representative sample powder for analysis. For XRD powder diffraction analyses, it is beneficial to have a powder that is extremely fine grained to reduce preferred orientation effects and to provide a statistically significant number of crystallites to the Xray beam. Although a 2 dimensional detector as used in the CHEMIN instrument will produce good re… more
Date: January 1, 2003
Creator: Chipera, S. J. (Steve J.); Bish, D. L. (David L.); Vaniman, D. T. (David T.); Sherrit, S.; Bar-Cohen, Yoseph & Blake, D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Miniature CVD-diamond corning drills for robotic sample collection and analysis.

Description: Coring tools have been used etlectivelv on the Moon, but to date no such tools have been used on any other extraterrestrial surface. The lunar experience includes both manual (Apollo) and robotic (Luna) systems . These coring systems were concerned primarily with acquiring samples from depth for return to Earth or for the creation of instrument emplacement holes (e .g ., heat probes). Current designs for planetary drills differ from the lunar tools primarily in that they are integrated with rob… more
Date: January 1, 2003
Creator: Vaniman, D. T. (David T.); Trava-Airoldi, V.J.; Bish, D. L. (David L.) & Chipera, S. J. (Steve J.)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Regional elemental abundances within South Pole-Aitken basin as measured with lunar prospector gamma-ray spectrometer data.

Description: South Pole-Aitken (SPA) basin has been a target of intense study since it is one of the largest impact basins in the solar system. It is thought that SPA basin excavated deep into the lunar crust and possibly even the mantle. Such conclusions have been supported by the observed mafic and thorium composition anomalies seen across the entire basin. One of the major goals of lunar and planetary science has been to measure and understand the composition of the non-mare materials within SPA basin. I… more
Date: January 1, 2003
Creator: Lawrence, David J. (David Jeffery),; Pieters, Carlé M.; Elphic, R. C. (Richard C.); Gasnault, O. M. (Olivier M.); Prettyman, T. H. (Thomas H.) & Feldman, W. C. (William C.)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Multi-mode wavepath depth imaging for the SEG/EAGE salt model

Description: Elastic depth imaging of both P-wave and S-wave prestack seismic reflection data is formulated as a degraded form of Kirchhoff migration known as Wavepath Migration (WM). Applications to the SEG/EAGE salt model show that the method is sufficiently versatile anti relaitively inexpensive. It handles S-wave data with at least the same accuracy as Pwave data when local mode conversions are removed. WM also provides an understanding of multi-mode illumination.
Date: January 1, 2003
Creator: Druzhinin, A. (Alexander); House, L. S. (Leigh S.) & Pajchel, J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Characteristics of stand-off detection of geological samples at MARS atmospheric pressure using laser-induced breakdown spectroscopy (LIBS).

Description: LIBS has been proposed as a new method for stand-off detection of geological samples for use on landers and rovers to Mars and studies are on-going to determine capabilities. Because of the severe size, weight, ruggedness and power requirements for space instrumentation and the need to maximize scientific return, it is important to benchmark capabilities with parameters representative of compact instrumentation likely to be used in a flight instrument. Some of these issues are addressed here.
Date: January 1, 2003
Creator: Cremers, D. A. (David A.); Arp, Z. A. (Zane A.); Knight, Andrew K.; Scherbarth, Nancy L.; Wiens, R. C. (Roger C.) & Maurice, S. (Sylvestre)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Coexistence of ferromagnetism and superconductivity in cerium, tellurium (1.82).

Description: CeTe1 .82 crystallizes in layered tetragonal Cu2Sb-type structure. At ambient pressure, the presence of the charge density wave (CDW) gap accompanying with a lattice distortion in the Te sheet is verified by electron-tunneling spectroscopy measurement. We measured the electrical resistivity on a CeTe1 .82 single crystal as a function of temperature and magnetic field (i // ab-plain, H// c-axis) performed under hydrostatic pressure up to 9 kbar using the 20 T superconduting magnet at the Pulse F… more
Date: January 1, 2003
Creator: Asmadi, A. M.; Jung, M. (Myung-Hwa); Kim, H. C. (Hyoung-Chan); Kamarad, J.; Lacerda, A. H. (Alex H.); Takabatake, T. (Toshiro) et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Multispectral thermal imager observations of the moon during total eclipse.

Description: Lunar eclipse temperature measurements are sensitive to rock populations because surfaces with abundant exposed rock have much higher mean thermal inertias than surfaces dominated by fine powders . When the Moon passes into the I :arth's shadow, the abrupt reduction in insolation causes surfacc elements to cool at rates which are ILnctions oftheir thermal inertia . The rock population is a lunction of the exposure of a surface unit, originally composed of solid igneous rock or impact mclt, to t… more
Date: January 1, 2003
Creator: Lawson, S. L. (Stefanie L.); Rodger, A. P. (Andrew Paul); Bender, S. C. (Steven C.); Lucey, P. G. (Paul G.) & Henderson, B. G. (Bradley G.)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Final Master Work Plan: Environmental Investigations at Former CCC/Usda Facilities in Kansas, 2002 Revision.

Description: The Commodity Credit Corporation (CCC) of the U.S. Department of Agriculture (USDA) has entered into an interagency agreement with the U.S. Department of Energy (DOE) under which Argonne National Laboratory provides technical assistance for hazardous waste site characterization and remediation for the CCC/USDA. Carbon tetrachloride is the contaminant of primary concern at sites in Kansas where former CCC/USDA grain storage facilities were located. Argonne applies its QuickSite(reg sign) Expedit… more
Date: January 23, 2003
Creator: Burton, J. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Proceedings of the 25th Seismic Research Review -- Nuclear Explosion Monitoring: Building the Knowledge Base

Description: These proceedings contain papers prepared for the 25th Seismic Research Review -- Nuclear Explosion Monitoring: Building the Knowledge Base, held 23-25 September, 2003 in Tucson, Arizona. These papers represent the combined research related to ground-based nuclear explosion monitoring funded by the National Nuclear Security Administration (NNSA), Defense Threat Reduction Agency (DTRA), Air Force Research Laboratory (AFRL), US Army Space and Missile Defense Command, and other invited sponsors. T… more
Date: September 23, 2003
Creator: Chavez, Francesca C. & Mendius, E. Louise
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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An evaluation of the active fracture concept with modelingunsaturated flow and transport in a fractured meter-sized block ofrock

Description: Numerical simulation is an effective and economical tool for optimally designing laboratory experiments and deriving practical experimental conditions. We executed a detailed numerical simulation study to examine the active fracture concept (AFC, Liu et al., 1998) using a cubic meter-sized block model. The numerical simulations for this study were performed by applying various experimental conditions, including different bottom flow boundaries, varying injection rates, and different fracture-ma… more
Date: May 30, 2003
Creator: Seol, Yongkoo; Kneafsey, Timothy J. & Ito, Kazumasa
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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