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Summary of FY 1999 Geosciences Research

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Summary of FY 1999 Geosciences Research DOE/SC-???? Summary of FY 1999 Geosciences Research December 2000 U.S. Department of Energy Office of Science Office of Basic Energy Sciences Division of Engineering and Geosciences Washington, D.C. 20585 CONTENTS Contents ............................................................................................................................. ii Foreword ............................................................................................................................. x The Geosciences Research Program in the Office of Basic Energy Sciences ................. xi PART I: ON-SITE ..................................................................................................................... 1 CONTRACTOR: Argonne National Laboratory................................................................................1 CATEGORY: Geochemistry...........................................................................................................1 Mineral-Fluid Interactions: Synchrotron Radiation Studies at the Advanced Photon Source............................................................................................................1 CONTRACTOR: Brookhaven National Laboratory...........................................................................2 CATEGORY: Geology, Geophysics, and Earth Dynamics..............................................................2 Study of the Microgeometry of Geological Materials Using Synchrotron Computed Microtomography .......................................................................................................................2 CATEGORY: Geochemistry..........................................................................................................3 Geochemistry of Organic Sulfur in Marine Sediments.................................................................3 CONTRACTOR: Lawrence Berkeley National Laboratory................................................................5 CATEGORY: Geophysics and Earth Dynamics..............................................................................5 High-Resolution Imaging of Electrical Conductivity Using Low-Frequency Electromagnetic Fields................................................................................................................5 Center for Computational Seismology (CCS)..............................................................................6 Deformation and Fracture of Poorly Consolidated Media............................................................7 Decomposition of Scattering and Intrinsic Attenuation on Rock with Heterogeneous Multiphase Fluids Distributions ..................................................................................................8 CATEGORY: Geochemistry...........................................................................................................9 Integrated Isotopic Studies of Geochemical Processes.................................................................9 Isotopic and Chemical Composition of Fault Zone Fluids .........................................................11 Clay Mineral Surface Geochemistry..........................................................................................13 Molecular-level studies of Fe-Al oxyhydroxide coating formation on quartz.............................14 CATEGORY: Hydrogeology....................................................................................................... 15 Geochemical and Isotopic Constraints on Processes in Oil Hydrogeology.................................15 Reactive Chemical Transport in Structured Porous Media: X-ray Microprobe and Micro-XANES Studies.......................................................................................................16 Unsaturated Fast Flow in Fractured Rock: Testing Film Flow and Aperture Influences.............17 Colloid Transport in Unsaturated Porous Media and Rock Fractures.........................................17 CONTRACTOR: Lawrence Livermore National Laboratory ........................................................... 19 CATEGORY: Geophysics and Earth Dynamics............................................................................ 19 Pore Scale Simulations of Rock Deformation, Fracture and Fluid Flow in Three Dimensions.....................................................................................................................19 ii Three-dimensional Analysis of Seismic Signatures and Characterizations of Fluids and Fractures in Anisotropic Formations ........................................................................20 Visco-, Thermo-, and Poroelasticity of Rocks and Rock/Fluid Mixtures....................................20 Reactive Solute Transport and Processes of Dissolution and Deposition in Single Fractures in Rock...........................................................................................................22 The Role of Carbon and Temperature in Determining Electrical Conductivity of Basins, Crust, and Mantle. ........................................................................................................23 Water distribution in partially saturated porous materials..........................................................23 CATEGORY: Geochemistry......................................................................................................... 24 An Experimental Investigation of Mechanisms Controlling Glass Dissolution ..........................24 Mineral Dissolution and Precipitation Kinetics: A Combined Atomic-Scale and Macro-Scale Investigation ........................................................................................................25 Collaborative Research: Studies for Surface Exposure Dating in Geomorphology.....................26 Dating depositional surfaces: Applications of in situ Cosmic-ray Exposure Dating ..................27 Thermodynamic and Transport Properties of Aqueous Geochemical Systems...........................28 CONTRACTOR: Los Alamos National Laboratory......................................................................... 30 CATEGORY: Geophysics and Earth Dynamics............................................................................ 30 Fast 3D Seismic Modeling and Prestack Depth Migration Using Generalized Screen Methods ........................................................................................................................30 The Role of Carbon and Temperature in Determining Electrical Conductivity of Basins, Crust, and Mantle. ........................................................................................................31 Nonlinear Elasticity in Earth Materials......................................................................................31 CATEGORY: Geochemistry......................................................................................................... 32 Uranium-Series Concordance Studies .......................................................................................32 Surface Exposure Dating in Geomorphology ............................................................................34 Microbial Dissolution of Iron Oxides........................................................................................34 CATEGORY: Solar-Terrestrial Physics........................................................................................ 35 Energy Transport in Space Plasma............................................................................................35 The Solar Wind-Magnetospheric Interaction .............................................................................36 Energetic Particle Acceleration and Transport...........................................................................36 CONTRACTOR: Oak Ridge National Laboratory............................................................................ 38 CATEGORY: Geochemistry......................................................................................................... 38 Thermodynamic Mixing Properties of C-O-H-N Fluids ............................................................38 Fundamental Research in the Geochemistry of Geothermal Systems.........................................39 Ion Microprobe Studies of Fluid-Rock Interaction ....................................................................41 Experimental Studies of Fundamental Stable Isotope Exchange Reactions................................42 Potentiometric Studies of Geochemical Processes.....................................................................43 Mechanisms and Rates of Isotope Exchange in Mineral-Fluid Systems.....................................45 CONTRACTOR: Pacific Northwest Laboratory.............................................................................. 46 CATEGORY: Geochemistry......................................................................................................... 46 Local Reactions on Carbonate Surfaces: Structure, Reactivity, and Solution .............................46 Geometric and Electronic Structure of Oxide Surfaces..............................................................47 Structure and Reactivity of Iron Oxide and Oxyhydroxide Surfaces and Interfaces ...................48 Electron Transfer at the Fe(III) Oxide-Microbe Interface ..........................................................51 iii CONTRACTOR: Sandia National Laboratories................................................................................ 53 CATEGORY: Geophysics and Earth Dynamics...........................................................................
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