A5048865539- High-pressure geophysics and materials
- Geological and Geochemical Analysis
- earthquake and tectonic studies
- Rock Mechanics and Modeling
- X-ray Diffraction in Crystallography
- Geochemistry and Geologic Mapping
- Clay minerals and soil interactions
- Nuclear Physics and Applications
- Hydrocarbon exploration and reservoir analysis
- Microstructure and mechanical properties
- Mineralogy and Gemology Studies
- Seismic Imaging and Inversion Techniques
- Crystal Structures and Properties
- Concrete and Cement Materials Research
- Calcium Carbonate Crystallization and Inhibition
- Mineral Processing and Grinding
- Geotechnical and Geomechanical Engineering
- Hydraulic Fracturing and Reservoir Analysis
- Planetary Science and Exploration
- Drilling and Well Engineering
- Seismic Waves and Analysis
- Microstructure and Mechanical Properties of Steels
- Enzyme Structure and Function
- Astro and Planetary Science
- Building materials and conservation
Planetary Science Institute
2014-2025
University of California, Berkeley
2014-2025
University of California System
1987-2022
Argonne National Laboratory
2007
Lawrence Berkeley National Laboratory
2007
Chevron (United States)
2007
NASA Earth Science
2007
GFZ Helmholtz Centre for Geosciences
2005
Los Alamos National Laboratory
1992
Heinrich Heine University Düsseldorf
1990-1991
The orientation distribution of a textured polycrystalline material has been traditionally determined from few individual pole figures lattice planes hkl, measured by x-ray or neutron diffraction. A new method is demonstrated that uses the whole diffraction spectrum, rather than extracted peak intensities, combining calculation with crystallographic Rietveld method. feasibility illustrated time-of-flight data experimentally deformed calcite. It possible to obtain quantitative information on...
The procedure to perform Rietveld texture analysis from diffraction images collected with CCDs or image plates is shown.In some cases only one transmission may be sufficient obtain an Orientation Distribution Function (ODF) if a number of peaks are included.The transformed in spectra and analyzed using the Maud program containing recently developed model well suited for this kind analysis.In work we will present results obtained custom laboratory plate camera analysis.The instrument curve...
The new edition of this popular textbook, once again, provides an indispensable guide for the next generation mineralogists. Designed use on one- or two-semester courses, second has been thoughtfully reorganised, making it more accessible to students, whilst still being suitable advanced mineralogy course. Additions include expanded introductions many chapters, a introductory chapter crystal chemistry, revised figures, and extended plates section containing beautiful colour photographs. Text...
One of the advantages a multidetector neutron time-of-flight diffractometer such as high pressure preferred orientation (HIPPO) at Los Alamos Neutron Science Center is capability to measure efficiently bulk materials. A routine experimental method for measurements, both ambient conditions, well or low temperatures, has been established. However, only recently complex data analysis streamlined make it straightforward noninitiated user. Here, we describe Rietveld texture HIPPO with computer...
Estimation of the Rayleigh number inner core suggests that this region is convecting. The flow pattern likely to produce crystallographic preferred orientation elastically anisotropic hexagonal closest packed (ϵ) phase iron, such compressional‐wave velocities would be greater in axial relative equatorial direction by roughly 1 percent. This result agreement with seismological evidence anisotropic.
The directional dependence of P and S wave velocities have been measured at pressures (up to 600 MPa) temperatures 700°C) in rocks from the Santa Rosa Mylonite Zone (southern California). During tectonism, these were progressively deformed granodiorite protolith mylonite ultimately phyllonite. mineralogical chemical composition is nearly identical. Thus provide excellent material for documenting effect microstructural textural changes on rock anisotropy. Velocity anisotropy increases...
Abstract Anisotropy of elastic properties in clay‐rich sedimentary rocks has been long‐standing interest. These are cap oil and gas reservoirs, as well seals for carbon sequestration. Elasticity shales approached by direct velocity measurements models based on microstructures. Here we revisiting the classical Kimmeridge shale studied Hornby (1998) first quantifying microstructural features such phase volume fractions, grain shapes orientations, pore distributions with advanced analytical...
Synchrotron X-ray diffraction images are increasingly used to characterize not only structural and microstructural features of polycrystalline materials, but also crystal preferred orientation distributions. Diffraction data can be analyzed quantitatively efficiently with the Rietveld method here detailed procedure is reported from experiment calibration two-dimensional detector full analysis sample. In particular, we emphasize advantage doing inside least-squares fitting instead a...
The material characteristics and elastic properties of aluminum‐substituted 11 Å tobermorite in the relict lime clasts 2000‐year‐old Roman seawater harbor concrete are described with TG ‐ DSC 29 Si MAS NMR studies, along nanoscale tomography, X ‐ray microdiffraction, high‐pressure diffraction synchrotron radiation applications. crystals have aluminum substitution for silicon tetrahedral bridging branching sites 11.49(3) interlayer (002) spacing. With prolonged heating to 350°C, exhibit...
Theories for deformation of polycrystals have been substantially refined, enabling us to model metals and minerals with considerable sophistication. So far, most modelling has confined single‐phase aggregates such as quartzite limestone. We present the first results a polyphase aggregate, peridotite, consisting 70% olivine 30% enstatite. The problem is approached viscoplastic self‐consistent theory satisfying stress equilibrium strain compatibility average polycrystal taking account...