WorldWideScience

Sample records for basaltic materials implications

  1. Basalt: structural insight as a construction material

    Indian Academy of Sciences (India)

    This paper explores the state of the art of basalt used in the construction industry with the overall layout of different subcategories of historical background starting from fibre development and different chemical and mechanical fibre properties to its applications in the field. Comparative studies have also been reported with ...

  2. Use of basaltic waste as red ceramic raw material

    Directory of Open Access Journals (Sweden)

    T. M. Mendes

    Full Text Available Abstract Nowadays, environmental codes restrict the emission of particulate matters, which result in these residues being collected by plant filters. This basaltic waste came from construction aggregate plants located in the Metropolitan Region of Londrina (State of Paraná, Brazil. Initially, the basaltic waste was submitted to sieving (< 75 μm and the powder obtained was characterized in terms of density and particle size distribution. The plasticity of ceramic mass containing 0%, 10%, 20%, 30%, 40% and 50% of basaltic waste was measured by Atterberg method. The chemical composition of ceramic formulations containing 0% and 20% of basaltic waste was determined by X-ray fluorescence. The prismatic samples were molded by extrusion and fired at 850 °C. The specimens were also tested to determine density, water absorption, drying and firing shrinkages, flexural strength, and Young's modulus. Microstructure evaluation was conducted by scanning electron microscopy, X-ray diffraction, and mercury intrusion porosimetry. Basaltic powder has similar physical and chemical characteristics when compared to other raw materials, and contributes to ceramic processing by reducing drying and firing shrinkage. Mechanical performance of mixtures containing basaltic powder is equivalent to mixtures without waste. Microstructural aspects such as pore size distribution were modified by basaltic powder; albite phase related to basaltic powder was identified by X-ray diffraction.

  3. A new basaltic glass microanalytical reference material for multiple techniques

    Science.gov (United States)

    Wilson, Steve; Koenig, Alan; Lowers, Heather

    2012-01-01

    The U.S. Geological Survey (USGS) has been producing reference materials since the 1950s. Over 50 materials have been developed to cover bulk rock, sediment, and soils for the geological community. These materials are used globally in geochemistry, environmental, and analytical laboratories that perform bulk chemistry and/or microanalysis for instrument calibration and quality assurance testing. To answer the growing demand for higher spatial resolution and sensitivity, there is a need to create a new generation of microanalytical reference materials suitable for a variety of techniques, such as scanning electron microscopy/X-ray spectrometry (SEM/EDS), electron probe microanalysis (EPMA), laser ablation inductively coupled mass spectrometry (LA-ICP-MS), and secondary ion mass spectrometry (SIMS). As such, the microanalytical reference material (MRM) needs to be stable under the beam, be homogeneous at scales of better than 10–25 micrometers for the major to ultra-trace element level, and contain all of the analytes (elements or isotopes) of interest. Previous development of basaltic glasses intended for LA-ICP-MS has resulted in a synthetic basaltic matrix series of glasses (USGS GS-series) and a natural basalt series of glasses (BCR-1G, BHVO-2G, and NKT-1G). These materials have been useful for the LA-ICP-MS community but were not originally intended for use by the electron or ion beam community. A material developed from start to finish with intended use in multiple microanalytical instruments would be useful for inter-laboratory and inter-instrument platform comparisons. This article summarizes the experiments undertaken to produce a basalt glass reference material suitable for distribution as a multiple-technique round robin material. The goal of the analytical work presented here is to demonstrate that the elemental homogeneity of the new glass is acceptable for its use as a reference material. Because the round robin exercise is still underway, only

  4. Implications of one-year basalt weathering/reactivity study for a basalt repository environment

    International Nuclear Information System (INIS)

    Pine, G.L.; Jantzen, C.M.

    1987-03-01

    The Savannah River Laboratory is testing the performance of the Defense Waste Processing Facility glass under conditions representing potential repository environments. For a basalt repository, one of the important issues is how rapidly reducing conditions are re-established after placement of the waste. The objective of this study was to examine the factors affecting the reactivity of the basalt. Construction of a nuclear waste repository in basalt will temporarily perturb the groundwater conditions, creating more oxidizing (air-saturated) conditions than an undisturbed repository system. Reducing conditions can be beneficial to the performance of waste glass and canisters, and may limit the transport of certain radionuclides. The Basalt Waste Isolation Project intends to use a backfill containing crushed basalt to re-establish the reducing conditions of the groundwater. The reactivity of the basalt has been found to be minimal once the fresh crushed surfaces have been weathered and the reactive intergranular glass component has been leached, e.g., by long-term surface storage. Crushing of the basalt for pneumatic emplacement of the backfill should, therefore, occur shortly before placement in the repository. This backfill must contain a minimum of 5 percent reactive fines (<100 mesh), to rapidly achieve reducing conditions. 23 refs., 21 figs., 18 tabs

  5. Americium migration in basalt and implications to repository risk analysis

    International Nuclear Information System (INIS)

    Rickert, P.G.

    1980-01-01

    Experiments were performed with americium as a minor component in groundwater. Batch adsorption, migration through column, and filtration experiments were performed. It was determined in batch experiments that americium is strongly adsorbed from solution. It was determined with filtration experiments that large percentages of the americium concentrations suspended by the contact solutions in batch experiments and suspended by the infiltrating groundwater in migration experiments were associated with particulate. Filtration was determined to be the primary mode of removal of americium from infiltrating groundwater in a column of granulated basalt (20 to 50 mesh) and an intact core of permeable basalt. Fractionally, 0.46 and 0.22 of the americium component in the infiltrating groundwater was transported through the column and core respectively. In view of these filtration and migration experiment results, the concept of K/sub d/ in the chromatographic sense is meaningless for predicting americium migration in bedrock by groundwater transport at near neutral pH

  6. Gas cluster ion beam for the characterization of organic materials in submarine basalts as Mars analogs

    Energy Technology Data Exchange (ETDEWEB)

    Sano, Naoko, E-mail: naoko.sano@ncl.ac.uk; Barlow, Anders J.; Cumpson, Peter J. [National EPSRC XPS Users' Service (NEXUS), School of Mechanical and Systems Engineering, Stephenson Building, Newcastle University, Newcastle-upon-Tyne NE1 7RU (United Kingdom); Purvis, Graham W. H.; Abbott, Geoffrey D.; Gray, Neil N. D. [School of Civil Engineering and Geosciences, Devonshire Building, Newcastle University, Newcastle-upon-Tyne NE1 7RU (United Kingdom)

    2016-07-15

    The solar system contains large quantities of organic compounds that can form complex molecular structures. The processing of organic compounds by biological systems leads to molecules with distinctive structural characteristics; thus, the detection and characterization of organic materials could lead to a high degree of confidence in the existence of extra-terrestrial life. Given the nature of the surface of most planetary bodies in the solar system, evidence of life is more likely to be found in the subsurface where conditions are more hospitable. Basalt is a common rock throughout the solar system and the primary rock type on Mars and Earth. Basalt is therefore a rock type that subsurface life might exploit and as such a suitable material for the study of methods required to detect and analyze organic material in rock. Telluric basalts from Earth represent an analog for extra-terrestrial rocks where the indigenous organic matter could be analyzed for molecular biosignatures. This study focuses on organic matter in the basalt with the use of surface analysis techniques utilizing Ar gas cluster ion beams (GCIB); time of flight secondary ion mass spectrometry (ToF-SIMS), and x-ray photoelectron spectroscopy (XPS), to characterize organic molecules. Tetramethylammonium hydroxide (TMAH) thermochemolysis was also used to support the data obtained using the surface analysis techniques. The authors demonstrate that organic molecules were found to be heterogeneously distributed within rock textures. A positive correlation was observed to exist between the presence of microtubule textures in the basalt and the organic compounds detected. From the results herein, the authors propose that ToF-SIMS with an Ar GCIB is effective at detecting organic materials in such geological samples, and ToF-SIMS combined with XPS and TMAH thermochemolysis may be a useful approach in the study of extra-terrestrial organic material and life.

  7. Gas cluster ion beam for the characterization of organic materials in submarine basalts as Mars analogs

    International Nuclear Information System (INIS)

    Sano, Naoko; Barlow, Anders J.; Cumpson, Peter J.; Purvis, Graham W. H.; Abbott, Geoffrey D.; Gray, Neil N. D.

    2016-01-01

    The solar system contains large quantities of organic compounds that can form complex molecular structures. The processing of organic compounds by biological systems leads to molecules with distinctive structural characteristics; thus, the detection and characterization of organic materials could lead to a high degree of confidence in the existence of extra-terrestrial life. Given the nature of the surface of most planetary bodies in the solar system, evidence of life is more likely to be found in the subsurface where conditions are more hospitable. Basalt is a common rock throughout the solar system and the primary rock type on Mars and Earth. Basalt is therefore a rock type that subsurface life might exploit and as such a suitable material for the study of methods required to detect and analyze organic material in rock. Telluric basalts from Earth represent an analog for extra-terrestrial rocks where the indigenous organic matter could be analyzed for molecular biosignatures. This study focuses on organic matter in the basalt with the use of surface analysis techniques utilizing Ar gas cluster ion beams (GCIB); time of flight secondary ion mass spectrometry (ToF-SIMS), and x-ray photoelectron spectroscopy (XPS), to characterize organic molecules. Tetramethylammonium hydroxide (TMAH) thermochemolysis was also used to support the data obtained using the surface analysis techniques. The authors demonstrate that organic molecules were found to be heterogeneously distributed within rock textures. A positive correlation was observed to exist between the presence of microtubule textures in the basalt and the organic compounds detected. From the results herein, the authors propose that ToF-SIMS with an Ar GCIB is effective at detecting organic materials in such geological samples, and ToF-SIMS combined with XPS and TMAH thermochemolysis may be a useful approach in the study of extra-terrestrial organic material and life.

  8. Processing and Material Characterization of Continuous Basalt Fiber Reinforced Ceramic Matrix Composites Using Polymer Derived Ceramics.

    Science.gov (United States)

    Cox, Sarah B.

    2014-01-01

    The need for high performance vehicles in the aerospace industry requires materials which can withstand high loads and high temperatures. New developments in launch pads and infrastructure must also be made to handle this intense environment with lightweight, reusable, structural materials. By using more functional materials, better performance can be seen in the launch environment, and launch vehicle designs which have not been previously used can be considered. The development of high temperature structural composite materials has been very limited due to the high cost of the materials and the processing needed. Polymer matrix composites can be used for temperatures up to 260C. Ceramics can take much higher temperatures, but they are difficult to produce and form in bulk volumes. Polymer Derived Ceramics (PDCs) begin as a polymer matrix, allowing a shape to be formed and cured and then to be pyrolized in order to obtain a ceramic with the associated thermal and mechanical properties. The use of basalt in structural and high temperature applications has been under development for over 50 years, yet there has been little published research on the incorporation of basalt fibers as a reinforcement in the composites. In this study, continuous basalt fiber reinforced PDCs have been fabricated and tested for the applicability of this composite system as a high temperature structural composite material. The oxyacetylene torch testing and three point bend testing have been performed on test panels and the test results are presented.

  9. Preliminary geochemical and physical testing of materials for plugging of man-made accesses to a repository in basalt

    International Nuclear Information System (INIS)

    Taylor, C.L.; Anttonen, G.J.; O'Rourke, J.E.; Allirot, D.

    1980-04-01

    The available data on environmental conditions (both natural and man-made) at the Hanford Site are sufficient for preconceptual plug system design. Results of the geochemical testing program indicate that preferred candidate plug materials are chemically nonreactive during laboratory tests that simulated some of the expected environmental conditions. Agitated, crushed-basalt samples and mixtures containing basalt were found to be self-cementing under the hydrothermal conditions. Materials considered most suitable for consideration in future test programs and preconceptual plug design are mixtures of natural materials (basalt, clay, glaciofluvial sand, gravel, and zeolite) and processed natural materials

  10. Sorption and desorption reactions of radionuclides with a crushed basalt-bentonite packing material

    International Nuclear Information System (INIS)

    Barney, G.S.; Lane, D.L.; Allen, C.C.; Jones, T.E.

    1985-04-01

    Current design of waste packages for disposal of high-level radioactive wastes in underground basalt formations includes a layer of packing material that surrounds the waste container. One of the functions of this material is to limit the release of radionuclides from a breached container into groundwater by providing a low hydraulic conductivity zone and by sorbing dissolved radionuclides. The objective of this study was to assess the radionuclide sorption capability of a proposed packing material composed of 25% sodium bentonite and 75% crushed basalt (by weight). Sorption and desorption reactions of several important waste radioelements (neptunium, uranium, plutonium, technetium, selenium, and radium) were investigated in the absence of air at 90 0 C. Uranium and neptunium were sorbed by slow reactions that follow first-order kinetics. The reaction rates are probably controlled by reduction of weakly sorbed uranium(VI) and neptunium(V) by ferrous iron in the crushed basalt component. Technetium(VII) was not reduced or sorbed under these conditions. Freundlich sorption and desorption isotherms for a given radionuclide were non-singular and show a strong tendency for sorption hysteresis. Applying the isotherm data to a one-dimensional transport model indicated that hysteretic sorption on the packing material provides an important safety factor in controlling releases of some radionuclides

  11. Basalt fibers: the green material of the XXI-century, for a sustainable restoration of historical buildings

    Directory of Open Access Journals (Sweden)

    Giacomo Di Ruocco

    2016-12-01

    Full Text Available In recent decades in the construction industry, the need to experience consolidation techniques with non-corroding materials is being developed. Studies and tests have been led about integration of basalt fibers in concrete structures: they have shown improvements both in terms of mechanical strength and in terms of intervention of consolidation durability (Ólafsson, Thorhallsson, 2009. The basalt rock can be used to produce not only basalt bars, but also fabrics, paddings, continuous filaments and basalt network. Some applications of these basalt-composites materials concern the consolidation of civil construction structures, thermal and acoustic insulation, security clothing, etc. Some years ago the Italian company ENEA (National Agency for New Technologies, Energy and Sustainable Economic Development has signed an agreement with HG GBF (one of the world's leading companies in the production of basalt fibers, for the verification of possible applications of this material in the construction field but also in the nautical and automotive ones. The use of basalt fiber in construction could present a series of advantages: natural origin, a cycle of production to lower energy impact compared to other fibers, a high chemical inertia and thus a high degree of durability, low thermal conductivity, good mechanical and thermo-acoustic properties, high fire resistance, a competitive cost and, in general, more environmental compatibility and sustainability than other synthetic fibers.

  12. The human impact on natural rock reserves using basalt, anorthosite, and carbonates as raw materials in insulation products

    DEFF Research Database (Denmark)

    Dahl, Tais Wittchen; Clausen, Anders U.; Hansen, Peter B.

    2011-01-01

    , and carbonates are widespread on all continents. Although basaltic rocks cover most of the ocean floor, these reserves are hidden below several kilometres of water and therefore are regarded as inaccessible. Instead, large igneous provinces on land constitute major basaltic reserves useful for human rock...... of these rock types are so large that they could supply current human demand for millions of years. The natural degradation of surface rocks occurs by physical and chemical weathering creating sediment that is transported along rivers and deposited in the ocean. Sediments are either obducted with continental......% basalt, 20 wt% anorthosite, and 40 wt% cement-bonded renewable materials. This study provides an overview of the natural cycle of these resources, including their abundances in nature, and sets the consumption by the stone wool industry and other human activities in perspective. Basalt, anorthosite...

  13. Elaboration of vitreous and vitrocrystalline basalt materials containing simulated radioactive ash wastes. Study of some physical properties and leaching behaviour

    International Nuclear Information System (INIS)

    Lebeau, M.J.

    1988-01-01

    This work is a preliminary study of a matrix for containment of incinerator ashes. Basalt presents a good capacity for ash incorporation (up to 50%), glasses obtained are homogeneous and the low viscosity at 1300 0 C allows an industrial preparation. Vitrocrystalline products have a dendritic texture which can be controlled by cooling rate and are composed of magnesioferrite, pyroxene, plagioclase and vitreous fraction depending on the filling material ratio. Uranium and thorium, for actinide simulation in ashes, are localized in the glass. Glass leaching decrease with ash content and the alteration film presents a better retention of some elements, such as uranium and thorium. Vitrocrystalline materials are less leachable than glasses. Interesting possibilities are shown for use of basalt as filling material in underground storage, since basalt decrease glass deterioration [fr

  14. Dust coatings on basaltic rocks and implications for thermal infrared spectroscopy of Mars

    Science.gov (United States)

    Johnson, J. R.; Christensen, P.R.; Lucey, P.G.

    2002-01-01

    Thin coatings of atmospherically deposited dust can mask the spectral characteristics of underlying surfaces on Mars from the visible to thermal infrared wavelengths, making identification of substrate and coating mineralogy difficult from lander and orbiter spectrometer data. To study the spectral effects of dust coatings, we acquired thermal emission and hemispherical reflectance spectra (5-25 μm; 2000-400 cm-1) of basaltic andesite coated with different thicknesses of air fall-deposited palagonitic soils, fine-grained ceramic clay powders, and terrestrial loess. The results show that thin coatings (10-20 μm) reduce the spectral contrast of the rock substrate substantially, consistent with previous work. This contrast reduction continues linearly with increasing coating thickness until a "saturation thickness" is reached, after which little further change is observed. The saturation thickness of the spectrally flat palagonite coatings is ~100-120 μm, whereas that for coatings with higher spectral contrast is only ~50-75 μm. Spectral differences among coated and uncoated samples correlate with measured coating thicknesses in a quadratic manner, whereas correlations with estimated surface area coverage are better fit by linear functions. Linear mixture modeling of coated samples using the rock substrate and coating materials as end-members is also consistent with their measured coating thicknesses and areal coverage. A comparison of ratios of Thermal Emission Spectrometer (TES) spectra of dark and bright intracrater and windstreak deposits associated with Radau crater suggests that the dark windstreak material may be coated with as much as 90% areal coverage of palagonitic dust. The data presented here also will help improve interpretations of upcoming mini-TES and Thermal Emission Imaging System (THEMIS) observations of coated Mars surface materials.

  15. Natural fumarolic alteration of fluorapatite, olivine, and basaltic glass, and implications for habitable environments on Mars.

    Science.gov (United States)

    Hausrath, Elisabeth M; Tschauner, Oliver

    2013-11-01

    Fumaroles represent a very important potential habitat on Mars because they contain water and nutrients. Global deposition of volcanic sulfate aerosols may also have been an important soil-forming process affecting large areas of Mars. Here we identify alteration from the Senator fumarole, northwest Nevada, USA, and in low-temperature environments near the fumarole to help interpret fumarolic and acid vapor alteration of rocks and soils on Mars. We analyzed soil samples and fluorapatite, olivine, and basaltic glass placed at and near the fumarole in in situ mineral alteration experiments designed to measure weathering under natural field conditions. Using synchrotron X-ray diffraction, we clearly observe hydroxyl-carbonate-bearing fluorapatite as a fumarolic alteration product of the original material, fluorapatite. The composition of apatites as well as secondary phosphates has been previously used to infer magmatic conditions as well as fumarolic conditions on Mars. To our knowledge, the observations reported here represent the first documented instance of formation of hydroxyl-carbonate-bearing apatite from fluorapatite in a field experiment. Retreat of olivine surfaces, as well as abundant NH4-containing minerals, was also characteristic of fumarolic alteration. In contrast, alteration in the nearby low-temperature environment resulted in formation of large pits on olivine surfaces, which were clearly distinguishable from the fumarolic alteration. Raman signatures of some fumarolically impacted surfaces are consistent with detection of the biological molecules chlorophyll and scytenomin, potentially useful biosignatures. Observations of altered minerals on Mars may therefore help identify the environment of formation and understand the aqueous history and potential habitability of that planet.

  16. Stability of Basalt plus Anhydrite plus Calcite at HP-HT: Implications for Venus, the Earth and Mars

    Science.gov (United States)

    Martin, A. M.; Righter, K.; Treiman, A. H.

    2010-01-01

    "Canali" observed at Venus surface by Magellan are evidence for very long melt flows, but their composition and origin remain uncertain. The hypothesis of water-rich flow is not reasonable regarding the temperature at Venus surface. The length of these channels could not be explained by a silicate melt composition but more likely, by a carbonate-sulfate melt which has a much lower viscosity (Kargel et al 1994). One hypothesis is that calcite CaCO3 and anhydrite CaSO4 which are alteration products of basalts melted during meteorite impacts. A famous example recorded on the Earth (Chicxulub) produced melt and gas rich in carbon and sulfur. Calcite and sulfate evaporites are also present on Mars surface, associated with basalts. An impact on these materials might release C- and S-rich melt or fluid. Another type of planetary phenomenon (affecting only the Earth) might provoke a high pressure destabilization of basalt+anhydrite+calcite. Very high contents of C and S are measured in some Earth s magmas, either dissolved or in the form of crystals (Luhr 2008). As shown by the high H content and high fO2 of primary igneous anhydrite-bearing lavas, the high S content in their source may be explained by subduction of an anhydrite-bearing oceanic crust, either directly (by melting followed by eruption) or indirectly (by release of S-rich melt or fluid that metasomatize the mantle) . Calcite is a major product of oceanic sedimentation and alteration of the crust. Therefore, sulfate- and calcite-rich material may be subducted to high pressures and high temperatures (HP-HT) and release S- and C-rich melts or fluids which could influence the composition of subduction zone lavas or gases. Both phenomena - meteorite impact and subduction - imply HP-HT conditions - although the P-T-time paths are different. Some HP experimental/theoretical studies have been performed on basalt/eclogite, calcite and anhydrite separately or on a combination of two. In this study we performed piston

  17. Overview of hydrothermal testing of waste-package barrier materials at the Basalt Waste Isolation Project

    International Nuclear Information System (INIS)

    1982-01-01

    The current Waste Package Department (WPD) hydrothermal testing program for the Basalt Waste Isolation Project (BWIP) has followed a systematic approach for the testing of waste-barrier-basalt interactions based on sequential penetration of barriers by intruding groundwaters. Present test activities in the WPD program have focused on determining radionuclide solubility limits (or steady-state conditions) of simulated waste forms and the long-term stability of waste package barriers under site-specific hydrothermal conditions. The resulting data on solution compositions and solid alteration products have been used to evaluate waste form degradation under conditions specific to a nuclear waste repository located in basalt (NWRB). Isothermal, time-invariant compositional data on sampled solutions have been coupled with realistic hydrologic flow data for near-field and far-field modeling for the calculation of meaningful radionuclide release rates. Radionuclides that are not strongly sorbed or precipitated from solution and that, therefore, may require special attention to ensure their isolation within the waste package have been identified. Taken together, these hydrothermal test data have been used to establish design requirements for waste packages located in basalt

  18. Rubbly Pahoehoe: Implication for Flood Basalt Eruptions and their Atmospheric Effects

    Science.gov (United States)

    Keszthelyi, L.; Keszthelyi, L.; Thordarson, T.; Self, S.

    2001-12-01

    Rubbly pahoehoe flows consist of a brecciated flow top, a pahoehoe base, and an interior similar to inflated pahoehoe flows. Rubbly pahoehoe flows can be found in many localities, making up ~20% of the Columbia River Basalt Group, ~50% of the lavas drilled on the Kerguelen Plateau, and a substantial fraction of the Icelandic lava flows. They are rare in the tholeiitic shield portions of the Hawaiian volcanoes, but are more common in the alkalic flows. They also appear to be the dominant type of Martian flood lava flow. Based primarily on observations from the 1873-1874 Laki Flow Field in Iceland, we suggest that rubbly pahoehoe flows form when the flux of lava within an inflating pahoehoe flow is so large that it rafts away the upper crust. This crust is then broken into large slabs and fragmented lobes, intruded by liquid lava from below, and folded into pressure ridges. This brecciation process quickly builds an insulating crust; for the Laki case a crust >4 m thick developed in less than a week. This rapid formation of a thick insulating crust allows lava to be transported over great distances with minimal cooling in eruptions lasting only weeks-months. Flood basalt flows emplaced in this manner could have had eruption rates on the order of 104 - 105 m^{3}s^{-1}. If active fissure segments were of the order of 10 km long, the volcanic plumes should have risen 9-16 km -- penetrating the stratosphere in most cases. The injection of \\sim10 Gt of SO_{2}$, F, and Cl into the stratosphere could have had serious climatic effects, thus further strengthening the plausible link between flood basalt eruptions and mass extinctions.

  19. Implications of Zn/Fe ratios for the sources of Colorado Plateau basalts

    Science.gov (United States)

    Rudzitis, S.; Reid, M. R.

    2011-12-01

    Early Miocene to recent mafic magmatism migrated across the Arizona Transition Zone towards the center of the stable Colorado Plateau at a rate of ~ 3-6 km/Myr (Roy et al., 2009). Present-day volcanic centers are close to a stepwise change in the thickness of the lithosphere between the Colorado Plateau and Basin and Range. Accordingly, volcanic migration might track progressive thinning of the lithosphere towards the center of the Colorado Plateau. This project aims to determine the conditions of melt generation across the transition zone in order to investigate the temporal/spatial correlation between volcanism and thinning of the Colorado Plateau lithosphere. Pressure and temperature estimates for Colorado Plateau basalts can be obtained from the Mg and Si contents of melts (Lee et al, 2009) but require melting of a peridotitic source. Eclogite and pyroxenite xenoliths reported in Colorado Plateau basalts show that melt sources could be olivine-poor. Zn/Fe ratios in melts can help to distinguish contributions from olivine-poor sources because they are sensitive to differences in bulk chemistry and to mineralogy (Le Roux et al., 2010). Specifically, Zn/Fe is not fractionated between melt, olivine, and orthopyroxene, but is highly fractionated when clinopyroxene and garnet are present. Our work to date has focused on laser ablation-IC-PMS analysis of individual olivine grains from high-Mg basalts (>8.0 wt. %) from the San Francisco and Mormon Mountain volcanic fields. Preliminary values of Zn/Fe ratios that represent the averages of multiple analyses of several grains in individual samples range from 7.9 to 9.3 (x10000). Variations of up to 1.7 (x10000) in the ratios exist between individual grains within samples and could be the result of co-crystallization of clinopyroxene with olivine. The lowest values in each sample should approach the Zn/Fe ratios of parental melts, and are, in turn, similar to MORB values and predicted peridotite melts. The results suggest

  20. How We Used NASA Lunar Set in Planetary Material Science Analog Studies on Lunar Basalts and Breccias with Industrial Materials of Steels and Ceramics

    Science.gov (United States)

    Berczi, S.; Cech, V.; Jozsa, S.; Szakmany, G.; Fabriczy, A.; Foldi, T.; Varga, T.

    2005-01-01

    Analog studies play important role in space materials education. Various aspects of analogies are used in our courses. In this year two main rock types of NASA Lunar Set were used in analog studies in respect of processes and textures with selected industrial material samples. For breccias and basalts on the lunar side, ceramics and steels were found as analogs on the industrial side. Their processing steps were identified on the basis of their textures both in lunar and in industrial groups of materials.

  1. Thermal and mass implications of magmatic evolution in the Lassen volcanic region, California, and minimum constraints on basalt influx to the lower crust

    Science.gov (United States)

    Guffanti, M.; Clynne, M.A.; Muffler, L.J.P.

    1996-01-01

    We have analyzed the heat and mass demands of a petrologic model of basaltdriven magmatic evolution in which variously fractionated mafic magmas mix with silicic partial melts of the lower crust. We have formulated steady state heat budgets for two volcanically distinct areas in the Lassen region: the large, late Quaternary, intermediate to silicic Lassen volcanic center and the nearby, coeval, less evolved Caribou volcanic field. At Caribou volcanic field, heat provided by cooling and fractional crystallization of 52 km3 of basalt is more than sufficient to produce 10 km3 of rhyolitic melt by partial melting of lower crust. Net heat added by basalt intrusion at Caribou volcanic field is equivalent to an increase in lower crustal heat flow of ???7 mW m-2, indicating that the field is not a major crustal thermal anomaly. Addition of cumulates from fractionation is offset by removal of erupted partial melts. A minimum basalt influx of 0.3 km3 (km2 Ma)-1 is needed to supply Caribou volcanic field. Our methodology does not fully account for an influx of basalt that remains in the crust as derivative intrusives. On the basis of comparison to deep heat flow, the input of basalt could be ???3 to 7 times the amount we calculate. At Lassen volcanic center, at least 203 km3 of mantle-derived basalt is needed to produce 141 km3 of partial melt and drive the volcanic system. Partial melting mobilizes lower crustal material, augmenting the magmatic volume available for eruption at Lassen volcanic center; thus the erupted volume of 215 km3 exceeds the calculated basalt input of 203 km3. The minimum basalt input of 1.6 km3 (km2 Ma)-1 is >5 times the minimum influx to the Caribou volcanic field. Basalt influx high enough to sustain considerable partial melting, coupled with locally high extension rate, is a crucial factor in development of Lassen volcanic center; in contrast. Caribou volcanic field has failed to develop into a large silicic center primarily because basalt supply

  2. Paleomagnetism of Jurassic-Cretaceous basalts from the Franz Josef Land Archipelago: tectonic implications

    Science.gov (United States)

    Abashev, Victor; Mikhaltsov, Nikolay; Vernikovsky, Valery

    2015-04-01

    New paleomagnetic data were obtained from a total of 158 oriented samples collected from the Jurassic magmatic complexes exposed on the Franz Joseph Land Archipelago (FJL). The field work was conducted during 2011 field season. Present study was focused on the tholeiitic basaltic lava flows that crop out on the Hooker Island. The samples were subjected to a detailed step-wise thermal demagnetization in temperatures up to 600 deg C or alternating field demagnetization with maximum filed up to 140 mT. Natural remanent magnetization (NRM) was measured with a 2G cryogenic magnetometer or a JR-6A spin-magnetometer housed in a magnetically shielded room at the Institute of Petroleum Geology and Geophysics, Siberian Branch of Russian Academy of Sciences. The main NRM carriers in the FJL samples are titanomagnetites with varying Ti-content. Magnetic remanence was unblocked in temperatures of 350-400 deg C. Some samples are characterized by unblocking temperatures of 560 deg C. The new paleomagnetic data were combined with those previously obtained from the early Cretaceous volcanics exposed on the FJL. A new mean paleomagnetic direction for the Jurassic rocks was calculated as D=78.3 deg, I=74.7 deg, a95=3.1 deg, k=194.3, N=13. A corresponding paleomagnetic pole is now located at Plat=62.1 deg; Plon=136.5 deg, A95=5.5 deg, K=63.6. New results suggest that the JFL occupied a significantly different position from that of the present day. However, in early Cretaceous the JFL was already located close to its present day position. We propose a rifting event between the North Barentz terrane (FJL and possibly Svalbard) and the counterpart of European tectonic domain. The rifting occurred during Early-Middle Jurassic. This event was accompanied by a significant shift of the FJL to the north-east for approximately 500 km. New results are in good agreement with a hypothesis that the FJL was passing over the Icelandic-Siberian hot spot during the Jurassic-Cretaceous time

  3. Compositional and Microtextural Analysis of Basaltic Feedstock Materials Used for the 2010 ISRU Field Tests, Mauna Kea, Hawaii

    Science.gov (United States)

    Marin, N.; Farmer, J. D.; Zacny, K.; Sellar, R. G.; Nunez, J.

    2011-12-01

    This study seeks to understand variations in composition and texture of basaltic pyroclastic materials used in the 2010 International Lunar Surface Operation-In-Situ Resource Utilization Analogue Test (ILSO-ISRU) held on the slopes of Mauna Kea Volcano, Hawaii (1). The quantity and quality of resources delivered by ISRU depends upon the nature of the materials processed (2). We obtained a one-meter deep auger cuttings sample of a basaltic regolith at the primary site for feed stock materials being mined for the ISRU field test. The auger sample was subdivided into six, ~16 cm depth increments and each interval was sampled and characterized in the field using the Multispectral Microscopic Imager (MMI; 3) and a portable X-ray Diffractometer (Terra, InXitu Instruments, Inc.). Splits from each sampled interval were returned to the lab and analyzed using more definitive methods, including high resolution Powder X-ray Diffraction and Thermal Infrared (TIR) spectroscopy. The mineralogy and microtexture (grain size, sorting, roundness and sphericity) of the auger samples were determined using petrographic point count measurements obtained from grain-mount thin sections. NIH Image J (http://rsb.info.nih.gov/ij/) was applied to digital images of thin sections to document changes in particle size with depth. Results from TIR showed a general predominance of volcanic glass, along with plagioclase, olivine, and clinopyroxene. In addition, thin section and XRPD analyses showed a down core increase in the abundance of hydrated iron oxides (as in situ weathering products). Quantitative point count analyses confirmed the abundance of volcanic glass in samples, but also revealed olivine and pyroxene to be minor components, that decreased in abundance with depth. Furthermore, point count and XRD analyses showed a decrease in magnetite and ilmenite with depth, accompanied by an increase in Fe3+phases, including hematite and ferrihydrite. Image J particle analysis showed that the

  4. Source implications for the different geochemical features of recent basaltic rocks from the northernmost part of the Cappadocian region, Turkey

    Science.gov (United States)

    Kurkcuoglu, Biltan; Yurur, Tekin

    2017-04-01

    Extensive magmatic activities developed since middle-Miocene, in the Cappadocian Region of Central Anatolia in Turkey. The nature and the sources of the magmatism were well-constrained by previous studies. Even though the sources of Strato-volcanoes and monogenetic vents were briefly explained, extremely young basalts (1.22 - 0.094 Ka) situated in northernmost part of Cappadocian Region and erupted between the two extentional faults, are not deeply investigated. Karaburna and Gülşehir lavas (1.22, 0.094 Ka, respectively, Dogan, 2011) are considered as a part of the Central Anatolian Volcanic Province, with extremely young ages, generated either at the final or after the final stage of the Cappadocian systems. These lavas have similar LIL and HFS elements patterns with each other, however, Karaburna samples are more enriched in HFS elements. These basalts also display approximately similar trends in LIL elements ( except Rb) and reflect HFS depletion relative to the OIB signature, moreover, HFS are more enriched compared to the Hasandag basaltic rocks, all these features suggesting, basaltic rocks are originated from the modified mantle source. Karaburna and Gülşehir basalts have low Nb/La (0.45-0.5 ; 0.35-0.42), Nb/Y( 0.33-.39; 0.27-0.44 Nb/Th (2.75-4.6; 1.26-1.68) and high Ba/Nb (22-32; 38-43) ratios suggesting the contributions from the crustal sources, moreoever, Gülşehir basaltic rocks differ from the Karaburna lavas with relatively low Nb/U ( 4.5-6.4) and high Ba/La ( 14.67-17.20) Th/La (0.22-0.27), whereas Karaburna samples are represented by low Ba/La (10.04-14.90) and Th/La (0.09-0.16) ratios, these geochemical features reveal that these differences are originated either from the different degrees of crustal involvement or change in the nature of the source in a short time interval. Of all the most recent basaltic products generated in central Anatolia are alkaline in nature, besides, the trace element content, multi-element patterns and HFS/LIL and

  5. Physical Volcanological and Petrogenetic Implications of Intra-lava Flow Geochemical Heterogeneity in the Columbia River Flood Basalt Province, USA.

    Science.gov (United States)

    Vye, C. L.; Barry, T. L.; Self, S.; Gannoun, A.; Burton, K. W.

    2007-12-01

    Continental flood basalt lava flows are widely assumed to represent compositionally uniform and rapidly erupted products of large well-mixed magma reservoirs. However, this study presents new data to illustrate systematic element and isotope variations within the flow field formed by an individual flood basalt eruption, both vertically within each sheet lobe and laterally between the constituent lobes. Such variation is significant in chemostratigraphic correlation of flood basalt lava units, in identifying source variability during one eruption, and in petrogenetic modeling. We investigate the extent and cause of compositional variation through tracing lava sheet lobes in a 2,660 cubic kilometer pahoehoe flow field formed during a single eruption in the Columbia River Basalt Province, USA. This is based on features related to emplacement by the inflation mechanism. This method of emplacement is supported by small but statistically significant and systematic major and trace element variation e.g. MgO 3.09- 4.55 wt%, Ni 17.5-25.6 ppm, indicative of fractional crystallisation. Re-Os isotopes indicate progressive crustal contamination of the magma over the timescale of a single flood basalt eruption. By establishing this physical volcanological framework, we determine a temporal link with the supply of lava from the vent(s) and apply it to investigate sequential magmatic evolution during the timescale of one eruption.

  6. Mass dependent fractionation of stable chromium isotopes in mare basalts: Implications for the formation and the differentiation of the Moon

    Science.gov (United States)

    Bonnand, Pierre; Parkinson, Ian J.; Anand, Mahesh

    2016-02-01

    We present the first stable chromium isotopic data from mare basalts in order to investigate the similarity between the Moon and the Earth's mantle. A double spike technique coupled with MC-ICP-MS measurements was used to analyse 19 mare basalts, comprising high-Ti, low-Ti and KREEP-rich varieties. Chromium isotope ratios (δ53Cr) for mare basalts are positively correlated with indices of magmatic differentiation such as Mg# and Cr concentration which suggests that Cr isotopes were fractionated during magmatic differentiation. Modelling of the results provides evidence that spinel and pyroxene are the main phases controlling the Cr isotopic composition during fractional crystallisation. The most evolved samples have the lightest isotopic compositions, complemented by cumulates that are isotopically heavy. Two hypotheses are proposed to explain this fractionation: (i) equilibrium fractionation where heavy isotopes are preferentially incorporated into the spinel lattice and (ii) a difference in isotopic composition between Cr2+ and Cr3+ in the melt. However, both processes require magmatic temperatures below 1200 °C for appreciable Cr3+ to be present at the low oxygen fugacities found in the Moon (IW -1 to -2 log units). There is no isotopic difference between the most primitive high-Ti, low-Ti and KREEP basalts, which suggest that the sources of these basalts were homogeneous in terms of stable Cr isotopes. The least differentiated sample in our sample set is the low-Ti basalt 12016, characterised by a Cr isotopic composition of -0.222 ± 0.025‰, which is within error of the current BSE value (-0.124 ± 0.101‰). The similarity between the mantles of the Moon and Earth is consistent with a terrestrial origin for a major fraction of the lunar Cr. This similarity also suggests that Cr isotopes were not fractionated by core formation on the Moon.

  7. Geochemistry of 24 Ma Basalts from Northeast Egypt: Implications for Small-Scale Convection Beneath the East African Rift System

    Science.gov (United States)

    Endress, C. A.; Furman, T.; Ali Abu El-Rus, M.

    2009-12-01

    Basalts ~24 Ma in the Cairo-Suez and Fayyum districts of NE Egypt represent the youngest and northernmost lavas potentially associated with the initiation of rifting of the Red Sea. The age of these basalts corresponds to a time period of significant regional magmatism that occurred subsequent to emplacement of 30 Ma flood basalts attributed to the Afar Plume in Ethiopia and Yemen. Beginning ~28 Ma, widespread magmatism occurred across supra-equatorial Africa in Hoggar (Algeria), Tibesti (Chad), Darfur (Sudan), Turkana (Kenya) and Samalat, Bahariya, Quesir and the Sinai Peninsula (Egypt) (e.g. Allegre et al., 1981; Meneisy, 1990; Baldridge et al., 1991; Wilson and Guiraud, 1992; Furman et al., 2006; Lucassen et al., 2008). Available geochemical and isotopic data indicate that Hoggar and Darfur basalts are similar to Turkana lavas, although no direct link between the N African lavas and the Kenya Plume has been made. New geochemical data on the NE Egyptian basalts provide insight into the thermochemical, isotopic, and mineralogical characteristics of the mantle beneath the region in which they were emplaced. The basalts are subalkaline with OIB-like incompatible trace element abundances and homogeneous major element, trace element and isotopic geochemistry. They display relatively flat ITE patterns, with notable positive Pb and negative P anomalies. Isotopic (143Nd/144Nd = 0.51274-0.51285, 87Sr/86Sr = 0.7049-0.7050) and trace element signatures (Ce/Pb = 16-22, Ba/Nb = 9-14, and La/Nb = 0.9-1.0) are consistent with melting of a sub-lithospheric source that has been slightly contaminated by continental crust during ascent and emplacement. The Pb isotopic ratios (206Pb/204Pb = 18.53-18.62, 207Pb/204Pb = 15.59-15.64, and 208Pb/204Pb = 38.80-39.00) in the Egyptian basalts are close to the range of those found in the 30 Ma Ethiopian flood basalts, which are distinct from the more highly radiogenic, high-μ type signature seen in basalts from Turkana, Darfur, and Hoggar

  8. Variability Of Some Soil Properties Along Toposequence On A Basaltic Parent Material Of Vom Plateau State Nigeria

    Directory of Open Access Journals (Sweden)

    Mahmud Abba Tijjani

    2017-02-01

    Full Text Available Topography influences the distribution of soil physico-chemical properties. This study assessed soil properties variation resulting from topographic aspect on basaltic parent material at Vom Jos Plateau State in the Southern Guinea zone of Nigeria in order to understand the general soil behaviour degree of development nutrients availability and its response to management activites. The result revealed variations in soil properties among the landscape segments which were probably due to the toposequence characteristics in soils. The samples were collected at depth of 0-15cm and 15-30cm parceled labeled and taken to laboratory for analysis of the selected for analysis. Clay silt and gravel contents were moderately variable CV22.9 15.42 and 32.55 respectively while sand showed less variability CV8.47. Organic carbon showed high variability CV38.08 while soil pH in H2O and CaCl2 showed less spatial variability with CV4.91 amp 6.45 respectively. Available phosphorus has high variability CV37.59. Magnesium K and Ca showed high spatial variability CV42.60 35.85 amp 35.84 respectively while Na and exchange acidity were moderately variable CV24.39 amp 24.27 respectively. However no regular pattern was observed in the distribution of the studied parameters. Therefore further studies might be required to fully understand and clarify the influence of aspect topography and vegetation types on soil properties for site-specific soil resource management practices in the study area.

  9. Compositional diversity of Late Cenozoic basalts in a transect across the southern Washington Cascades: Implications for subduction zone magmatism

    Science.gov (United States)

    Leeman, William P.; Smith, Diane R.; Hildreth, Wes; Palacz, Zen; Rogers, Nick

    1990-11-01

    Major volcanoes of the Southern Washington Cascades (SWC) include the large Quaternary stratovolcanoes of Mount St. Helens (MSH) and Mount Adams (MA) and the Indian Heaven (IH) and Simcoe Mountain (SIM) volcanic fields. There are significant differences among these volcanic centers in terms of their composition and evolutionary history. The stratovolcanoes consist largely of andesitic to dacitic lavas and pyroclastics with minor basalt flows. IH consists dominantly of basaltic with minor andesite lavas, all erupted from monogenetic rift and cinder cone vents. SIM has a poorly exposed andesite to rhyolite core but mainly consists of basaltic lavas erupted from numerous widely dispersed vents; it has the morphology of a shield volcano. Distribution of mafic lavas across the SWC is related to north-northwest trending faults and fissure zones that indicate a significant component of east-west extension within the area. There is overlap in eruptive history for the areas studied, but it appears that peak activity was progressively older (MSH (slab-metasomatized subarc mantle. The juxtaposition of such different mantle domains within the lithospheric mantle is viewed as a consequence of (1) tectonic mixing associated with accretion of oceanic and island arc terranes along the Pacific margin of North America prior to Neogene time, and possibly (2) a seaward jump in the locus of subduction at about 40 Ma. The Cascades arc is unusual in that the subducting oceanic plate is very young and hot. We suggest that slab dehydration outboard of the volcanic front resulted in a diminished role of aqueous fluids in generating or subsequently modifying SWC magmas compared to the situation at most convergent margins. Furthermore, with low fluid flux conditions, basalt generation is presumably triggered by other processes that increase the temperature of the mantle wedge (e.g., convective mantle flow, shear heating, etc.).

  10. Petrogenesis of the Jiaoziding granitoids and associated basaltic porphyries: Implications for extensive early Neoproterozoic arc magmatism in western Yangtze Block

    Science.gov (United States)

    Li, Jun-Yong; Wang, Xiao-Lei; Gu, Zhi-Dong

    2018-01-01

    Middle Neoproterozoic (ca 860-750 Ma) granitoids are widely distributed in the western margin of the Yangtze Block, China, yet their magma sources and tectonic settings are unclear. The geochronology and geochemistry of the granitoids and associated basaltic porphyries, which intruded the 970 Ma Tongmuliang arc volcanic rocks in the Jiaoziding area (east of Pingwu county), were investigated in this study. LA-ICP-MS zircon U-Pb dating indicates that the Jiaoziding granitoids and basaltic porphyries were formed at 795 ± 6 Ma and 790 ± 20 Ma, respectively. The granitoids have high SiO2 (69.2-76.9 wt%), K2O (2.3-5.6 wt%), and Na2O (3.2-5.1 wt%) contents, and a low Al2O3 (12.4-14.5 wt%) content. The basaltic porphyries contain high concentrations of TiO2 ( 3 wt%) and high field strength elements, have steep rare earth element patterns, and are depleted in Nd and Hf isotopes. Batch partial-melting modelling indicates that the Jiaoziding granitoids could have been derived by 5% and 50-70% partial melting of Tongmuliang mafic rocks and quartz-keratophyres, respectively. Formation of the basaltic porphyries by melting of upwelling asthenospheric mantle would have been facilitated by extensive lithospheric delamination during the Neoproterozoic. This study established a link between mid-Neoproterozoic granitic magmatism and 970 Ma juvenile arc crust, indicating that extensive early Neoproterozoic juvenile arc crust, and partial melting of this crust in an extensional setting, favoured the formation of middle Neoproterozoic granitic rocks along the W-NW margin of the Yangtze Block.

  11. Geochemistry, 40Ar/39Ar geochronology, and geodynamic implications of Early Cretaceous basalts from the western Qinling orogenic belt, China

    Science.gov (United States)

    Zhang, Feifei; Wang, Yuejun; Cawood, Peter A.; Dong, Yunpeng

    2018-01-01

    The Qinling-Dabie orogenic belt was formed by the collision of the North and South China Cratons during the Early Mesozoic and subsequently developed into an intracontinental tectonic process during late Mesozoic. Field investigations identified the presence of late Mesozoic basalts in the Duofutun and Hongqiang areas in the western Qinling orogenic belt. The petrogenesis of these basalts provides an important constraint on the late Mesozoic geodynamics of the orogen. The representative basaltic samples yield the 40Ar/39Ar plateau age of about 112 Ma. These samples belong to the alkaline series and have SiO2 ranging from 44.98 wt.% to 48.19 wt.%, Na2O + K2O from 3.44 wt% to 5.44 wt%, and MgO from 7.25 wt.% to 12.19 wt.%. They demonstrate the right-sloping chondrite-normalized REE patterns with negligible Eu anomalies (1.00-1.10) and PM-normalized patterns enriched in light rare earth element, large ion lithophile element and high field strength element, similar to those of OIB rocks. These samples additionally show an OIB-like Sr-Nd isotopic signature with εNd(t) values ranging from +6.13 to +10.15 and initial 87Sr/86Sr ratios from 0.7028 to 0.7039, respectively. These samples are geochemically subdivided into two groups. Group 1 is characterized by low Al2O3 and high TiO2 and P2O5 contents, as well as high La/Yb ratios (>20), being the product of the high-pressure garnet fractionation from the OIB-derived magma. Group 2 shows higher Al2O3 but lower P2O5 contents and La/Yb ratios (<20) than Group 1, originating from asthenospheric mantle with input of delaminated lithospheric component. In combination with available data, it is proposed for the petrogenetic model of the Early Cretaceous thickened lithospheric delamination in response to the asthenospheric upwelling along the western Qinling orogenic belt.

  12. U-Pb zircon geochronology and geochemistry of Late Jurassic basalts in Maevatanana, Madagascar: Implications for the timing of separation of Madagascar from Africa

    Science.gov (United States)

    Yang, Xi-An; Chen, Yu-Chuan; Hou, Ke-Jun; Liu, Shan-Bao; Liu, Jia-Jun

    2014-12-01

    Magmatic zircon ages for the Maevatanana basalts in Madagascar indicate that Madagascar separated from Africa at 149.8 ± 2.1 Ma. Rocks produced by this basaltic magmatism associated with rifting are characterized by low SiO2 (49.6-50.3 wt.%), high total FeO (>13.9 wt.%), TiO2 (>3.7 wt.%), and P2O5 (>0.5 wt.%), and extremely high Na2O/K2O (3.08-3.27). Geochemical variations can be ascribed to significant fractional crystallization of clinopyroxene and plagioclase. The mineralogical and geochemical characteristics of the Maevatanana basalts suggest affinities with calc-alkaline basalt. Additionally the basalts have distinct ocean-island-basalt-like geochemical features that may be related to the Marion plume. We speculate that the Maevatanana basalts are the product of the Marion mantle plume related to separation of Madagascar from Africa in the Late Jurassic.

  13. Cyclic pressurisation of Mount St Helens dacites and basalt. Laboratory results and implications for lava dome monitoring

    Science.gov (United States)

    Kendrick, Jackie; Dainty, Matthew; Smith, Rosanna; Sammonds, Peter; Pallister, John; Meredith, Phillip

    2010-05-01

    Lava domes are frequently subjected to cyclic heating and pressurisation, which may weaken the dome rocks, leading to renewed extrusion, explosions or collapse. These heating and loading cycles can be recreated in the laboratory, allowing the level of crack damage caused by these cycles to be established through analysing elastic moduli. Acoustic emissions (AEs) indicate the timing of cracking, and can also be used to interpret precursory seismicity for eruption prediction. Experiment samples are from Mount St. Helens, USA: 3 dacites from the Pine Creek eruptive period (2.9-2.55 ka), a Castle Creek age basalt (2.55-1.895 ka), and 4 dacites from the 2004-2008 eruption. Each sample was cut into several cylindrical cores (25 mm diameter and 62.5-70 mm long). Some samples were then heated and cooled at 1˚C/ minute to a target temperature of 600o C or 900o C, and held for 2 hours to achieve thermal equilibrium. This heating can cause cracking due to contrasts in thermal expansion of different minerals. Dynamic elastic moduli were calculated for each sample using ultrasonic wave velocity, density and porosity for later comparison to static elastic moduli gathered during deformation. One core of each sample was loaded to failure in uniaxial compression in order to find the short term strength of the sample. For all cyclic loading tests, conducted on pre-heated and unheated cores, samples were loaded at 10-5 s-1 strain rate then unloaded to 5MPa. Subsequent cycles had an increasing peak load. Most had the same rate for unloading, with a few samples unloaded instantaneously. Axial, radial and volumetric strain were determined from the recorded displacement throughout the experiment and used with the axial stress measurements to calculate static elastic moduli. Samples loaded to failure with no cycling generally failed at higher stresses than their cyclically loaded counter-parts, whilst rapid unloading increased their strength. Failure stresses of the dacite lava dome

  14. Emplacement controls for the basaltic-andesitic radial dikes of Summer Coon volcano and implications for flank vents at stratovolcanoes

    Science.gov (United States)

    Harp, A. G.; Valentine, G. A.

    2018-02-01

    Mafic flank eruptions are common events that pose a serious hazard to the communities and infrastructure often encroaching on the slopes of stratovolcanoes. Flank vent locations are dictated by the propagation path of their feeder dikes. The dikes are commonly thought to propagate either laterally from the central conduit or vertically from a deeper source. However, these interpretations are often based on indirect measurements, such as surface deformation and seismicity at active systems, and several studies at eroded volcanoes indicate the propagation paths may be more complex. We investigated the Oligocene age Summer Coon volcano (Colorado, USA), where erosion has exposed over 700 basaltic-andesitic radial dikes, to constrain the propagation directions, geometries, and spatial distributions of mafic dikes within a stratovolcano. The mean fabric angle of aligned plagioclase crystals was measured in oriented samples from the margins of 77 dikes. Of the 41 dikes with statistically significant flow fabrics, 85% had fabric angles that were inclined—plunging both inward and outward relative to the center of the volcano. After comparing fabric angles to those reported in other studies, we infer that, while most of the dikes with outward-plunging fabrics descended toward the flanks from a source within the edifice and near its axis, dikes with inward-plunging fabrics ascended through the edifice and toward the flanks from a deeper source. A possible control for the inclination of ascending dikes was the ratio between magma overpressure and the normal stress in the host rock. While higher ratios led to high-angle propagation, lower ratios resulted in inclined emplacement. Dikes crop out in higher frequencies within a zone surrounding the volcano axis at 2500 m radial distance from the center and may be the result of ascending dikes, emplaced at similar propagation angles, intersecting the current level of exposure at common distances from the volcano axis. The process

  15. Basaltic cannibalism at Thrihnukagigur volcano, Iceland

    Science.gov (United States)

    Hudak, M. R.; Feineman, M. D.; La Femina, P. C.; Geirsson, H.

    2014-12-01

    Magmatic assimilation of felsic continental crust is a well-documented, relatively common phenomenon. The extent to which basaltic crust is assimilated by magmas, on the other hand, is not well known. Basaltic cannibalism, or the wholesale incorporation of basaltic crustal material into a basaltic magma, is thought to be uncommon because basalt requires more energy than higher silica rocks to melt. Basaltic materials that are unconsolidated, poorly crystalline, or palagonitized may be more easily ingested than fully crystallized massive basalt, thus allowing basaltic cannibalism to occur. Thrihnukagigur volcano, SW Iceland, offers a unique exposure of a buried cinder cone within its evacuated conduit, 100 m below the main vent. The unconsolidated tephra is cross-cut by a NNE-trending dike, which runs across the ceiling of this cave to a vent that produced lava and tephra during the ~4 Ka fissure eruption. Preliminary petrographic and laser ablation inductively coupled mass spectrometry (LA-ICP-MS) analyses indicate that there are two populations of plagioclase present in the system - Population One is stubby (aspect ratio 2.1), subhedral to euhedral, and has much higher Ba/Sr ratios. Population One crystals are observed in the cinder cone, dike, and surface lavas, whereas Population Two crystals are observed only in the dike and surface lavas. This suggests that a magma crystallizing a single elongate population of plagioclase intruded the cinder cone and rapidly assimilated the tephra, incorporating the stubbier population of phenocrysts. This conceptual model for basaltic cannibalism is supported by field observations of large-scale erosion upward into the tephra, which is coated by magma flow-back indicating that magma was involved in the thermal etching. While the unique exposure at Thrihnukagigur makes it an exceptional place to investigate basaltic cannibalism, we suggest that it is not limited to this volcanic system. Rather it is a process that likely

  16. Basalt waste added to Portland cement

    Directory of Open Access Journals (Sweden)

    Thiago Melanda Mendes

    2016-08-01

    Full Text Available Portland cement is widely used as a building material and more than 4.3 billion tons were produced in 2014, with increasing environmental impacts by this industry, mainly through CO2 emissions and consumption of non-removable raw materials. Several by-products have been used as raw materials or fuels to reduce environmental impacts. Basaltic waste collected by filters was employed as a mineral mixture to Portland cement and two fractions were tested. The compression strength of mortars was measured after 7 days and Scanning Electron Microscopy (SEM and Electron Diffraction Scattering (EDS were carried out on Portland cement paste with the basaltic residue. Gains in compression strength were observed for mixtures containing 2.5 wt.% of basaltic residue. Hydration products observed on surface of basaltic particles show the nucleation effect of mineral mixtures. Clinker substitution by mineral mixtures reduces CO2 emission per ton of Portland cement.

  17. Geochemistry of sulfur isotopes in basaltic rocks

    International Nuclear Information System (INIS)

    Hubberten, H.W.; Puchelt, H.

    1980-01-01

    Sulfur isotope ratios in oceanic basalts from three different localities (Bermuda Triangle, East Pacific Rise, and Galapagos Spreading Centre and in terrestrial basalts from Saudi Arabia have been analyzed by mass spectroscopy. In order to recognize and to interpret, if possible, secondary isotopic changes of basalts, various sulfurous materials occurring together with basalts gypsum, deep thermal pyrites) have been investigated too. By mechanochemical sample preparation it was possible to determine various sulfur carriers separately. Sulfides occurring as droplets in basalts showed values of -0.4 to -0.8 0 / 00 in materials from Bermuda Triangle, Galapagos Spreading Centre, and Saudi Arabia. The values are in agreement with those suggested for primary sulfur in the earth mantle. The basalts of East Pacific Rise show a significant 34 S enrichment with a mean value of +3 0 / 00 , which may be caused by processes in the course of magmatic differentiation. Because of secondary effects sulfate sulfur, including secondary pyrite, varies considerably in its sulfur isotope ratio (delta values between -12 to +22 0 / 00 ). Samples without recognizable secondary effects have delta values of about +1.5 0 / 00 , which can be supposed for primary sulfates. Mechanically separated pyrites from deep thermal superimposed basalts show slightly negative 34 S values

  18. Reconfiguration on nanocrossbar using material implication

    Indian Academy of Sciences (India)

    ... a new nonvolatile memory element, can be usedto overcome these limitations. In this paper, we propose an implication-NOR logic-gate-based FPGA architecture using memristors for implementation of logic functions and with embedded memory for storing data. The automation algorithm for the same is presented.

  19. High-precision 40Ar/39Ar dating of Quaternary basalts from Auckland Volcanic Field, New Zealand, with implications for eruption rates and paleomagnetic correlations

    Science.gov (United States)

    Leonard, Graham S.; Calvert, Andrew T.; Hopkins, Jenni L.; Wilson, Colin J. N.; Smid, Elaine R.; Lindsay, Jan M.; Champion, Duane E.

    2017-09-01

    The Auckland Volcanic Field (AVF), which last erupted ca. 550 years ago, is a late Quaternary monogenetic basaltic volcanic field (ca. 500 km2) in the northern North Island of New Zealand. Prior to this study only 12 out of the 53 identified eruptive centres of the AVF had been reliably dated. Careful sample preparation and 40Ar/39Ar analysis has increased the number of well-dated centres in the AVF to 35. The high precision of the results is attributed to selection of fresh, non-vesicular, non-glassy samples from lava flow interiors. Sample selection was coupled with separation techniques that targeted only the groundmass of samples with 10 μm wide, coupled with ten-increment furnace step-heating of large quantities (up to 200 mg) of material. The overall AVF age data indicate an onset at 193.2 ± 2.8 ka, an apparent six-eruption flare-up from 30 to 34 ka, and a ≤ 10 kyr hiatus between the latest and second-to-latest eruptions. Such non-uniformity shows that averaging the number of eruptions over the life-span of the AVF to yield a mean eruption rate is overly simplistic. Together with large variations in eruption volumes, and the large sizes and unusual chemistry within the latest eruptions (Rangitoto 1 and Rangitoto 2), our results illuminate a complex episodic eruption history. In particular, the rate of volcanism in AVF has increased since 60 ka, suggesting that the field is still in its infancy. Multiple centres with unusual paleomagnetic inclination and declination orientations are confirmed to fit into a number of geomagnetic excursions, with five identified in the Mono Lake, two within the Laschamp, one within the post-Blake or Blake, and two possibly within the Hilina Pali.

  20. Implications of smart materials in advanced prosthetics

    Science.gov (United States)

    Lenoe, Edward M.; Radicic, William N.; Knapp, Michael S.

    1994-05-01

    This research reviews common implant materials and suggests smart materials that may be used as substitutes. Current prosthetic technology, including artificial limbs, joints, and soft and hard tissue, falls short in comprehensive characterization of the chemo-mechanics and materials relationships of the natural tissues and their prosthetic materials counterparts. Many of these unknown chemo-mechanical properties in natural tissue systems maintain cooperative function that allows for optimum efficiency in performance and healing. Traditional prosthetic devices have not taken into account the naturally occurring electro-chemo-mechanical stress- strain relationships that normally exist in a tissue system. Direct mechanical deformation of tissue and cell membrane as a possible use of smart materials may lead to improved prosthetic devices once the mechanosensory systems in living tissues are identified and understood. Smart materials may aid in avoiding interfacial atrophy which is a common cause of prosthetic failure. Finally, we note that advanced composite materials have not received sufficient attention, they should be more widely used in prosthetics. Their structural efficiency allows design and construction of truly efficient bionic devices.

  1. Energy implications of recycling packaging materials

    Energy Technology Data Exchange (ETDEWEB)

    Gaines, L.L. [Argonne National Lab., IL (United States); Stodolsky, F. [Argonne National Lab., Washington, DC (United States)

    1994-03-01

    In 1992, Congress sought to rewrite the United States comprehensive solid waste legislation -- the Resource Conservation and Recovery Act (RCRA). Commodity-specific recycling rates were proposed for consumer-goods packaging materials and newsprint We compare the impacts on energy, materials use, and landfill volume of recycling at those rates to the impacts for alternative methods of material disposition to determine the optimum for each material. After products have served their intended uses, there are several alternative paths for material disposition. These include reuse, recycling to the same product, recycling to a lower-valued product, combustion for energy recovery, incineration without energy recovery, and landfill. Only options considered to be environmentally sound are Included. Both houses of Congress specifically excluded combustion for energy recovery from counting towards the recovery goats, probably because combustion is viewed as a form of disposal and is therefore assumed to waste resources and have n environmental effects. However, co-combustion in coal-fired plants or combustion in appropriately pollution-controlled waste-to-energy plants Is safe, avoids landfill costs, and can displace fossil fuels. In some cases, more fossil fuels can be displaced by combustion than by recycling. We compare the alternative life-cycle energies to the energies for producing the products from virgin materials. Results depend on the material and on the objective to be achieved. There are trade-offs among possible goals. For instance, paper packaging recycling conserves trees but may require greater fossil-fuel input than virgin production. Therefore, the objectives for proposed legislation must be examined to see whether they can most effectively be achieved by mandated recycling rates or by other methods of disposition. The optimal choices for the United States may not necessarily be the same as those for Europe and other parts of the world.

  2. Implications of material selection on the design of packaging machinery.

    Science.gov (United States)

    Merritt, J P

    2009-01-01

    Material selection has significant implications on the design and cost of horizontal-form-fill-seal packaging machinery. To avoid excessive costs, machine redesigns and project delays, material selection must be reconciled early in the project and revisited throughout the construction of the machine.

  3. Middle Triassic back-arc basalts from the blocks in the Mersin Mélange, southern Turkey: Implications for the geodynamic evolution of the Northern Neotethys

    Science.gov (United States)

    Sayit, Kaan; Bedi, Yavuz; Tekin, U. Kagan; Göncüoglu, M. Cemal; Okuyucu, Cengiz

    2017-01-01

    The Mersin Mélange is a tectonostratigraphic unit within the allochthonous Mersin Ophiolitic Complex in the Taurides, southern Turkey. This chaotic structure consists of blocks and tectonic slices of diverse origins and ages set in a clastic matrix of Upper Cretaceous age. In this study, we examine two blocks at two different sections characterized by basaltic lava flows alternating with radiolarian-bearing pelagic sediments. The radiolarian assemblage extracted from the mudstone-chert alternation overlying the lavas yields an upper Anisian age (Middle Triassic). The immobile element geochemistry suggests that the lava flows are predominantly characterized by sub-alkaline basalts. All lavas display pronounced negative Nb anomalies largely coupled with normal mid-ocean basalt (N-MORB)-like high field strength element (HFSE) patterns. On the basis of geochemical modelling, the basalts appear to have dominantly derived from spinel-peridotite and pre-depleted spinel-peridotite sources, while some enriched compositions can be explained by contribution of garnet-facies melts from enriched domains. The overall geochemical characteristics suggest generation of these Middle Triassic lavas at an intra-oceanic back-arc basin within the northern branch of Neotethys. This finding is of significant importance, since these rocks may represent the presence of the oldest subduction zone found thus far from the Neotethyan branches. This, in turn, suggests that the rupturing of the Gondwanan lithosphere responsible for the opening of the northern branch of Neotethys should have occurred during the Lower Triassic or earlier.

  4. Public health implications of radioluminous materials

    International Nuclear Information System (INIS)

    Moghissi, A.A.; Carter, M.W.

    1975-07-01

    This study evaluates the safety, efficacy, and relative merits of commonly used radioluminous materials. A comparative risk benefit analysis is carried out for radium-226, promethium-147, and tritium. These materials have been used most extensively in the dial painting industry for the illumination of timepieces and other instruments where self illumination offered an advantage. The study concludes that radium should not be used for dial painting because tritium can be used to accomplish the same results with substantially less exposure. Before a large-scale application of promethium-147, methods must be developed to determine the body burden of workers as a result of occupational exposure. (auth)

  5. The radiogenic and stable Sr isotope geochemistry of basalt weathering in Iceland: Role of hydrothermal calcite and implications for long-term climate regulation

    Science.gov (United States)

    Andrews, M. Grace; Jacobson, Andrew D.

    2017-10-01

    Several studies have examined the geochemistry of Icelandic rivers to quantify the relationship between basalt weathering and long-term climate regulation. Recent research has suggested that the chemical weathering of hydrothermal and metamorphic calcite contributes significant quantities of HCO3- to the Icelandic riverine flux (Jacobson et al., 2015). Because the HCO3- derives from volcanic CO2 that was sequestered in mineral form prior to atmospheric injection, the strength of the basalt weathering feedback occurring in Iceland may be lower than previously realized. To test these hypotheses, we analyzed the radiogenic and stable Sr isotope composition (87Sr/86Sr and δ88/86Sr) of the same suite of water, rock, and mineral samples as examined in Jacobson et al. (2015), and we developed a simple model of the long-term C cycle that considers the transformation of volcanic CO2 to HCO3- during subsurface silicate weathering, which is a precursor to hydrothermal calcite formation. Interpretations based on 87Sr/86Sr and Ca/Sr ratios suggest that conservative, three-component mixing between basalt, calcite, and atmospheric deposition adequately explains river geochemistry. On average, the δ88/86Sr values of glacial and non-glacial rivers (0.414‰ and 0.388‰, respectively) are generally higher than those for basalt (0.276‰); however, calcite δ88/86Sr values (0.347‰) are also higher than those for basalt and span the range of riverine values. Thus, riverine δ88/86Sr values are also consistent three-component mixing between basalt, calcite, and atmospheric deposition. Isotopic fractionation is not required to explain riverine trends. Finally, model equations for the long-term C cycle demonstrate that subsurface silicate weathering reduces the magnitude of the volcanic CO2 degassing flux, which in turn causes the atmosphere to stabilize at lower pCO2 values compared to the case where no subsurface silicate weathering occurs. However, the proportion of the net

  6. A Strongly Calc-alkaline Suite in the Midst of the Tholeiitic Columbia River Basalt Province: Implications for Generating the Calc-alkaline Trend Without Subduction Processes

    Science.gov (United States)

    Steiner, A. R.; Streck, M. J.

    2012-12-01

    The mid-Miocene lavas of the Strawberry Volcanics (SV), distributed over 3,400 km2 in NE Oregon, comprise a diverse volcanic suite, which span the range of compositions from basalt to rhyolite. The volcanic suite is mainly composed of calc-alkaline (CA) basaltic andesite and andesite, yet tholeiitic (TH) lavas of basalt to andesite occur as well. The SV lies in the heart of nearly coeval flood basalts of the Columbia River province of the Pacific Northwest. The unique combination of strongly CA rocks of the SV in a non-subduction setting provide an excellent opportunity to study controls on inducing CA evolution in the midst of a TH province and independent of processes taking places at an active subduction zone. New 40Ar/39Ar ages indicate CA basaltic andesites to andesites of the SV erupted at least from 14.78±0.13 Ma to 12.44±0.12 Ma demonstrating that CA magmatism of the SV was ongoing during the eruptions of the tholeiitic Wanapum Basalt member of the Columbia River Basalt Group (CRBG). This range will likely be extended to even older ages in the future because existent age dates did not include samples from near the base of the SV. Thickness of intermediate lavas flows of the SV range from 15 m to as thin as 2 m and lavas are characterized by mostly phenocryst poor lithologies. When phenocrysts are abundant they are very small suggesting growth late during eruption. Single lava flow sections can include on the order of 30 conformable flows, testifying to a vigorous eruption history. The thickest andesitic sections are located in the glacially carved mountains of the Strawberry Mountain Wilderness (i.e. Strawberry Mountain, High Lake, and Slide Lake) where several vent complexes are exposed, which are delineated by dikes and plugs with finely interlocking plutonic textures, cross-cutting SV lava flows. Dikes generally strike NW-SE. Subtle variations in major and trace element compositions exist between TH and CA lavas of the SV. The CA lavas of the SV are

  7. Public health implications of radioluminous materials

    International Nuclear Information System (INIS)

    Moghissi, A.A.; Carter, M.W.

    1975-07-01

    The safety, efficacy, and relative merits of radium, tritium, and promethium in radioluminous materials, particularly as used in the dial paint of timepieces and instruments, were evaluated. The reduced use of radium in recent years is reflected in estimates of the population dose for 1973--3600 person-rem from 24 million tritium watches versus 2500 person-rem from 8.4 million radium clocks. Had radium still been used in watches, the dose could have been significantly higher. No reliable data are available on the activity of promethium used for this purpose. Assuming a minimum dose of 6100 person-rem from all these radionuclides, an average of 0.03 mrem/year is estimated for the U.S. population. Because of the unavoidable radiation hazard, it is recommended that radium no longer be used in radioluminous materials. Furthermore, the 'frivolous' use of other radionuclides for this purpose should be discouraged

  8. Perunica microplate in Silurian period: implications from basalt geochemistry, palaeomagnetism and faunas (Prague Basin, Teplá-Barrandian Unit, Bohemian Massif)

    Czech Academy of Sciences Publication Activity Database

    Tasáryová, Z.; Pruner, Petr; Manda, Š.; Janoušek, V.; Schnabl, Petr; Štorch, Petr; Frýda, J.; Šifnerová, Kristýna; Erban, V.

    -, č. 1 (2012), s. 213-214 ISSN 0007-6104. [Length scales, times scales and relative contribution of Variscan orogenic events to formation of European crust. 22.05.2012-23.05.2012, Sassari] R&D Projects: GA ČR GAP210/10/2351 Institutional research plan: CEZ:AV0Z30130516 Keywords : basalt geochemistry * palaeomagnetism * palaeobiography Subject RIV: DE - Earth Magnetism, Geodesy, Geography

  9. Facies architecture of the Etjo Sandstone Formation and its interaction with the Basal Etendeka Flood Basalts of northwest Namibia: implications for offshore prospectivity

    Energy Technology Data Exchange (ETDEWEB)

    Jerram, D.A. [Institut fur Geologie, Universitat Wuerzburg (Germany); University of Durham (United Kingdom). Dept. of Geological Sciences; Mountney, N. [University of Liverpool (United Kingdom). Dept. of Earth Sciences; Stollhofen, H. [Institut fur Geologie, Universitat Wuerzburg (Germany)

    1999-07-01

    The Basal Etendeka Flood Basalt stratigraphy in the Huab Basin of northwest Namibia comprises a series of lava flows interleaved with aeolian sandstone bodies of the Etjo Sandstone Formation. The sandstone units are characterized by three main types: (1) the major erg - a mixed aeolian and fluvian facies up to 150 m thick ; (2) minor ergs - aeolian facies which occur directly above the first volcanic units and are up to 60 m thick; (3) isolated bodies - multidune, single dune and lava topography infills. A variety of bypass surfaces identified by sand-filled cracks and sediment - lava breccias occur on lava top surfaces. Preserved ripples and pahoehoe lava imprints indicate that the aeolian sand dunes were actively migrating during basalt emplacement. Observations recorded in the Basal Etendeka Flood Basalts which may be of relevance to offshore hydrocarbon exploration include: a major-minor erg relationship resulting in large sandbodies up to 60 m thick which occur directly after the first volcanic units; the occurrence of sand-filled fissures up to 36 m in depth which would greatly influence connectivity in an offshore setting; the identification of bypass surfaces as marker horizons which may laterally correlate with isolated sandbodies.

  10. The origin of plagioclase phenocrysts in basalts from continental monogenetic volcanoes of the Kaikohe-Bay of Islands field, New Zealand: implications for magmatic assembly and ascent

    Science.gov (United States)

    Coote, Alisha; Shane, Phil; Stirling, Claudine; Reid, Malcolm

    2018-02-01

    Late Quaternary, porphyritic basalts erupted in the Kaikohe-Bay of Islands area, New Zealand, provide an opportunity to explore the crystallization and ascent history of small volume magmas in an intra-continental monogenetic volcano field. The plagioclase phenocrysts represent a diverse crystal cargo. Most of the crystals have a rim growth that is compositionally similar to groundmass plagioclase ( An65) and is in equilibrium with the host basalt rock. The rims surround a resorbed core that is either less calcic ( An20-45) or more calcic (> An70), having crystallized in more differentiated or more primitive melts, respectively. The relic cores, particularly those that are less calcic (rim growths around the entrained antecrystic and xenocrystic cargo. The recharge also entrained cognate gabbros that occur as inclusions, and produced mingled groundmasses. Multi-stage magmatic ascent and interaction is indicated, and is consistent with the presence of a partial melt body in the lower crust detected by geophysical methods. This crystallization history contrasts with traditional concepts of low-flux basaltic systems where rapid ascent from the mantle is inferred. From a hazards perspective, the magmatic system inferred here increases the likelihood of detecting eruption precursor phenomena such as seismicity, degassing and surface deformation.

  11. The Jurassic-Cretaceous basaltic magmatism of the Oued El-Abid syncline (High Atlas, Morocco): Physical volcanology, geochemistry and geodynamic implications

    Science.gov (United States)

    Bensalah, Mohamed Khalil; Youbi, Nasrrddine; Mata, João; Madeira, José; Martins, Línia; El Hachimi, Hind; Bertrand, Hervé; Marzoli, Andrea; Bellieni, Giuliano; Doblas, Miguel; Font, Eric; Medina, Fida; Mahmoudi, Abdelkader; Beraâouz, El Hassane; Miranda, Rui; Verati, Chrystèle; De Min, Angelo; Ben Abbou, Mohamed; Zayane, Rachid

    2013-05-01

    Basaltic lava flows, dykes and sills, interbedded within red clastic continental sedimentary sequences (the so called "Couches Rouges") are widespread in the Oued El-Abid syncline. They represent the best candidates to study the Jurassic-Cretaceous magmatism in the Moroccan High Atlas. The volcanic successions were formed during two pulses of volcanic activity, represented by the Middle to Upper Jurassic basaltic sequence B1 (1-4 eruptions) and the Lower Cretaceous basaltic sequence B2 (three eruptions). Whether belonging to the B1 or B2, the lava flows present morphology and internal structures typical of inflated pahoehoe. Our geochemical data show that, at least for Jurassic magmatism, the dykes, and sills cannot be considered as strictly representing the feeders of the sampled lava flows. The Middle to Upper Jurassic pulse is moderately alkaline in character, while the Lower Cretaceous one is transitional. Crustal contamination plays a minor role in the petrogenesis of these magmas, which were generated by variable partial melting degrees of a garnet-bearing mantle source. Magmatism location was controlled by pre-existing Hercynian fault systems reactivated during a Middle to Upper Jurassic-Cretaceous rifting event. The associated lithospheric stretching induced melting, by adiabatic decompression, of enriched low-solidus infra-lithospheric domains.

  12. Hydrothermal evolution of repository groundwaters in basalt

    International Nuclear Information System (INIS)

    Apps, J.A.

    1984-01-01

    Groundwaters in the near field of a radioactive waste repository in basalt will change their chemical composition in response to reactions with the basalt. These reactions will be promoted by the heat generated by the decaying waste. It is important to predict both the rate and the extent of these reactions, and the secondary minerals produced, because the alteration process controls the chemical environment affecting the corrosion of the canister, the solubility and complexation of migrating radionuclides, the reactivity of the alteration products to radionuclides sorption, and the porosity and permeability of the host rock. A comprehensive review of the literature leads to the preliminary finding that hydrothermally altering basalts in geothermal regions such as Iceland lead to a secondary mineralogy and groundwater composition similar to that expected to surround a repository. Furthermore, laboratory experiments replicating the alteration conditions approximate those observed in the field and expected in a repository. Preliminary estimates were made of the rate of hydration and devitrification of basaltic glass and the zero-order dissolution rate of basaltic materials. The rates were compared with those for rhyolitic glasses and silicate minerals. Preliminary calculations made of mixed process alteration kinetics, involving pore diffusion and surface reaction suggest that at temperatures greater than 150 0 C, alteration proceeds so rapidly as to become pervasive in normally fractured basalt exposed to higher temperatures in the field. 70 references

  13. Thermoluminescence dating of Hawaiian basalt

    Science.gov (United States)

    May, Rodd James

    1979-01-01

    The thermoluminescence (TL) properties of plagioclase separates from 11 independently dated alkalic basalts 4,500 years to 3.3 million years old and 17 tholeiitic basalts 16 years to 450,000 years old from the Hawaiian Islands were investigated for the purpose of developing a TL dating method for young volcanic rocks. Ratios of natural to artificial TL intensity, when normalized for natural radiation dose rates, were used to quantify the thermoluminescence response of individual samples for age-determination purposes. The TL ratios for the alkalic basalt plagioclase were found to increase with age at a predictable exponential rate that permits the use of the equation for the best-fit line through a plot of the TL ratios relative to known age as a TL age equation. The equation is applicable to rocks ranging in composition from basaltic andesite to trachyte over the age range from about 2,000 to at least 250,000 years before present (B.P.). The TL ages for samples older than 50,000 years have a calculated precision of less than :t 10 percent and a potential estimated accuracy relative to potassium-argon ages of approximately :t 10 percent. An attempt to develop a similar dating curve for the tholeiitic basalts was not as successful, primarily because the dose rates are on the average lower than those for the alkalic basalts by a factor of 6, resulting in lower TL intensities in the tholeiitic basalts for samples of equivalent age, and also because the age distribution of dated material is inadequate. The basic TL properties of the plagioclase from the two rock types are similar, however, and TL dating of tholeiitic basalts should eventually be feasible over the age range 10,000 to at least 200,000 years B.P. The average composition of the plagioclase separates from the alkalic basalts ranges from oligoclase to andesine; compositional variations within this range have no apparent effect on the TL ratios. The average composition of the plagioclase from the tholeiitic

  14. 40Ar-39Ar dating of terrestrial and exterrestrial materials. Basalts from the Japan Sea floor, Deccan Plateau and meteorites from Antarctica

    International Nuclear Information System (INIS)

    Kaneoka, Ichiro; Takigami, Yutaka.

    1994-01-01

    Through a series of 40 Ar- 39 Ar dating for terrestrial and exterrestrial samples, the results for basalts from the Japan Sea floor, Deccan Plateau and for meteorites from Antarctica give significant information concerning their formation histories. 40 Ar- 39 Ar ages of basalts from the Japan Sea floor give a constraint that the Japan Sea floor was formed at least 20 Ma. 40 Ar- 39 Ar ages for dyke samples from the Deccan Plateau indicate a possibility for the occurrence of a little younger ages than that of the main plateau formations by a few million years. Meteorites collected from Antarctica show some variable 40 Ar- 39 Ar ages reflecting their different thermal histories. (author)

  15. Experimental alterations on ceramic interest basalts

    International Nuclear Information System (INIS)

    Sanfeliu-Montolio, T.; Ballbe-Lonch, E.; Querlat-Mitjans, I.; Juan-Abril, A.; Fuente-Cellell, C. de la

    1991-01-01

    This study presents the results and conclusion extracted of the chemical and mineralogical analysis made on 12 samples of recent and subrecent (IV series) Canary Island's basalt, that have been subject to different attack processes in order to cause in them controlled mineralogical alterations. The methods used were: optical analysis, x-ray fluorescence analysis and x-ray diffraction. The object of this work is to determine the alterability of these basaltic rocks that have ceramic interest since it's possible its use in same ceramic manufactures and also as petrurgic raw material. (author)

  16. Plasma sprayed basalt/chromium oxide coatings

    Czech Academy of Sciences Publication Activity Database

    Ageorges, H.; Medarhri, Z.; Ctibor, Pavel; Fauchais, P.

    2007-01-01

    Roč. 11, č. 1 (2007), s. 71-82 ISSN 1093-3611 Institutional research plan: CEZ:AV0Z20430508 Keywords : Chromia, basalt * plasma spraying * microstructure * phase analysis Subject RIV: JH - Ceramics, Fire-Resistant Materials and Glass Impact factor: 0.268, year: 2007

  17. The Cretaceous adakitic-basaltic-granitic magma sequence on south-eastern margin of the North China Craton: Implications for lithospheric thinning mechanism

    Science.gov (United States)

    Liu, Sheng-Ao; Li, Shuguang; Guo, Sushu; Hou, Zhenhui; He, Yongsheng

    2012-03-01

    We present here a combined study of Early Cretaceous granodiorites, granites and mafic rocks from the Bengbu area on south-eastern margin of the North China Craton (NCC), in order to provide insights into the thinning mechanism of lithosphere on the cratonic margins. Zircon U-Pb and Ar-Ar dating reveals an adakitic-basaltic-granitic magma sequence with the adakitic intrusions (granodiorites; 123-115 Ma) formed prior to the granites and mafic dykes (both ca.112 Ma). The granodiorites are geochemically similar to low-Mg# adakitic rocks and isotopically have enriched Sr-Nd-Hf compositions, low radiogenic Pb (206Pb/204Pbi = 16.524-17.017), and mantle-like δ18Ozircon (5.8 ± 0.5‰). They were originated from the thickened lower continental crust (LCC) of the NCC. In contrast, the granites have low Sr/Y (generation of granitic and basaltic magmas. Anatexis of the pre-existing thickened LCC at 123-115 Ma that attenuated the LCC itself and left the residues denser as a result of felsic (adakitic) melt extraction is proposed to have resulted in gravitational instability and foundering of the lithosphere. Such a temporal sequence of magma generation and processes of lithospheric thinning also occurred on north margin of the NCC and are quite similar to the mountain-root removal beneath the Dabie Orogen in central China. This manifests that previous melting of the LCC is perhaps an important trigger responsible for lithospheric foundering in orogenic belts and cartonic margins, where the lithosphere underwent pre-thickening by continental collisions and had stabilized over a long time.

  18. Reaction microtextures in entrapped xenoliths in alkali basalts from the Deccan large igneous province, India: Implications to the origin and evolution

    Science.gov (United States)

    Chattopadhaya, Soumi; Ghosh, Biswajit; Morishita, Tomoaki; Nandy, Sandip; Tamura, Akihiro; Bandyopadhyay, Debaditya

    2017-05-01

    The onset of the end-Mesozoic continental rift magmatism in the Deccan volcanic province (DVP), India is marked by alkali magmatism. Lithospheric fragments occurring as xenoliths/xenocrysts entrapped in alkaline basalts from the Kutch area of the DVP preserve reaction microtextures giving an insight into the processes linked to their origin. We interpret the flower texture, an aggregate of systematically arranged tiny diopside crystals, as a product of interactions between ghost quartz xenocrysts with alkaline silica-undersaturated melt. The mantle xenoliths, mostly represented by spinel lherzolites and wehrlites have been infiltrated by melt. The orthopyroxenes present at the margin of the xenoliths or in contact with infiltrated melt exhibit a coronal texture composed of olivine, clinopyroxene and glass around them. The compositions of cores of primary olivines at places retain mantle signatures, whereas, the margins are reequilibrated. Secondary olivines and clinopyroxenes at reaction coronas have a wide range of compositions. Primary clinopyroxenes and spinels in close vicinity to the orthopyroxene corona display a sieve texture defined by clear inclusion-free cores and a compositionally different spongy altered rim with worm-shaped or bubbly inclusions dominantly filled with glass. The rims are marked with higher Ca, Mg-lower Na, Al for clinopyroxenes and higher Ti, Cr-lower Mg, Al for spinels in comparison to their cores. The coronal texture around orthopyroxenes and spongy texture in clinopyroxenes and spinels in these xenoliths are interpreted to be genetically linked. The silicate glasses in the xenoliths show large compositional variations and they are much more siliceous and alkali-rich in comparison to the host basalts. The petrography and mineral chemistry suggest host magma-peridotite interaction during or after the entrainment of the xenoliths, corroborating well with the experimental findings.

  19. Study of crystallization of a basalt glass

    International Nuclear Information System (INIS)

    Nishimura, Fernando Takahiro; Hashizume, Camila Mina; Toffoli, Samuel Marcio

    2009-01-01

    Basalt vitreous ceramics posses industrial importance by presenting high mechanical resistance to the abrasion. It was studied the obtention and the crystallization of a glass obtained from a basalt of Campinas, Sao Paulo, Brazil, aiming to develop a material with great abrasive resistance. Fusions were made at 1400 deg Celsius in electrical oven and in alumina crucible, of fine residues of basalt mining. The obtained glass was treated in a crystallization temperature of 880 deg Celsius, determined by DSC, by various time of treatment. The present main crystalline phases, detected by XRD, were the magnesium-ferrite (MgFe 2 O 4 ) and the diopsid Ca(Mg,Fe,Al)(Si,Al) 2 O 6 . Analysing the density by the Archimedes methodology and the DRX it was possible to follow the crystallization kinetic up.

  20. The Relative Rates of Secondary Hydration in Basalt and Rhyolite, and the use of δD as a Paleoclimate Indicator: Implications for Paleoenvironmental and Volcanic Degassing Studies

    Science.gov (United States)

    Seligman, A. N.; Bindeman, I. N.

    2014-12-01

    The δD-H2O correlation is important for volcanic degassing and secondary hydration trends. We utilize the caibration of the TC/EA - MAT 253 continuous flow system, which permits us to analyze wt.% H2O and its δD extracted from 1-8 mg of glass with as little as 0.1 wt% H2O. Tephra that has been secondarily hydrated with meteoric water is widely used as a paleoenvironmental tool, but the rate of secondary hydration, the relative amounts of primary magmatic (degassed) and secondary meteoric water, and the retention of primary and secondary δD values are not well understood. To quantify these processes, we use a natural experiment involving dated Holocene tepha in Kamchatka and Oregon. Our research illustrates the drastic difference in hydration rates between silicic (hydrated after ~1.5 ka) and mafic tephra, which is not hydrated in the Holocene (similar to results for submarine volcanic glasses), and andesitic tephra with intermediate degrees of hydration. The 0.05-7.3 ka basaltic scoria from Klyuchevskoy volcano retains ≤0.45 wt.% primary magmatic H2O, with δD values from -99 to -121 ‰. Four other 0.05-7.6 ka basaltic tephra units from Kamchatka with 65 wt.% have higher (1.5 -3.4) wt.% H2O and δD values between -115 - -160 ‰. We interpret the lower δD values and higher water contents (opposite of the magmatic degassing trend) to be a characteristic of secondary hydration in regions of higher latitude such as Kamchatka and Oregon. We are also investigating 7.7 ka Mt. Mazama tephra in Oregon that are known to be fully hydrated and cover nearly 5000 km2 northeast of Crater Lake and range in elevation from ~1.3-1.9 km to understand the δD and δ18O details of the hydrated water's correspondence with local Holocene meteoric waters. In the future, we plan to use a combination of δD in mid-high latitude precipitation to delineate δD-H2O hydration trends to better understand the distinction between primary magmatic and secondary meteoric water in volcanic

  1. Pressure grouting of fractured basalt flows

    Energy Technology Data Exchange (ETDEWEB)

    Shaw, P.; Weidner, J.; Phillips, S.; Alexander, J.

    1996-04-01

    This report describes a field trial of pressure grouting in basalt and the results of subsequent coring and permeability measurement activities. The objective was to show that the hydraulic conductivity of fractured basalt bedrock can be significantly reduced by pressure injection of cementitious materials. The effectiveness of the pressure grout procedure was evaluated by measuring the change in the hydraulic conductivity of the bedrock. The extent of grout penetration was established by analyzing postgrout injection drilling chips for the presence of a tracer in the grout and also by examining cores of the treated basalt. Downhole radar mapping was used to establish major lava flow patterns and follow water movement during a surface infiltration test. A site called Box Canyon, which is located northwest of the INEL, was chosen for this study due to the similarity of this surface outcrop geology to that of the underlying bedrock fracture system found at the Radioactive Waste Management Complex. This study showed that hydraulic conductivity of basalt can be reduced through pressure grouting of cementitious material.

  2. Rare earth elements exploitation, geopolitical implications and raw materials trading

    Science.gov (United States)

    Chemin, Marie-Charlotte

    2015-04-01

    Rare earth elements (REE) correspond to seventeen elements of the periodic table. They are used in high technology, cracking, electric cars' magnet, metal alloy for batteries, and also in phone construction or ceramics for electronic card. REEs are an important resource for high technology. This project targets 16 years old students in the subject "personalized aid" and will last six weeks. The purpose of this project is to develop autonomy and research in groups for a transdisciplinary work. This project gathers knowledge in geology, geography and economics. During the first session students analyze the geology applications of the REE. They begin the analysis with learning the composition in different rocks such as basalt and diorite to make the link with crystallization. Then they compare it with adakite to understand the formation of these rocks. In the second session, they study REE exploitation. We can find them as oxides in many deposits. The principal concentrations of rare earth elements are associated with uncommon varieties of igneous rocks, such as carbonatites. They can use Qgis, to localize this high concentration. In the third session, they study the environmental costs of REE exploitation. Indeed, the exploitation produces thorium and carcinogenic toxins: sulphates, ammonia and hydrochloric acid. Processing one ton of rare earths produces 2,000 tons of toxic waste. This session focuses, first, on Baotou's region, and then on an example they are free to choose. In the fourth session, they study the geopolitical issues of REE with a focus on China. In fact this country is the largest producer of REE, and is providing 95% of the overall production. REE in China are at the center of a geopolitical strategy. In fact, China implements a sort of protectionism. Indeed, the export tax on REE is very high so, as a foreign company, it is financially attractive to establish a manufacturing subsidiary in China in order to use REE. As a matter of fact

  3. Trace Element Geochemistry of Basaltic Tephra in Maar Cores; Implications for Centre Correlation, Field Evolution, and Mantle Source Characteristics of the Auckland Volcanic Field, New Zealand

    Science.gov (United States)

    Hopkins, J. L.; Leonard, G.; Timm, C.; Wilson, C. J. N.; Neil, H.; Millet, M. A.

    2014-12-01

    Establishing volcanic hazard and risk management strategies hinges on a detailed understanding of the type, timing and tephra dispersal of past eruptions. In order to unravel the pyroclastic eruption history of a volcanic field, genetic links between the deposits and eruption source centre need to be established. The Auckland Volcanic Field (AVF; New Zealand) has been active for ca. 200 kyr and comprises ca. 53 individual centres covering an area of ca. 360km2. These centres show a range of sizes and eruptive styles from maar craters and tuff rings, to scoria cones and lava flows consistent with both phreatomagmatic and magmatic eruptions. Superimposition of the metropolitan area of Auckland (ca. 1.4 million inhabitants) on the volcanic field makes it critically important to assess the characteristics of the volcanic activity, on which to base assessment and management of the consequent hazards. Here we present a geochemical approach for correlating tephra deposits to their source centres. To acquire the most complete stratigraphic record of pyroclastic events, maar crater cores from different locations, covering various depths and thus ages across the field were selected. Magnetic susceptibility and x-ray density scanning of the cores was used to identify the basaltic tephra horizons, which were sampled and in-situ analysis of individual shards undertaken for major and trace elements using EPMA and LA-ICP-MS techniques, respectively. Our results show that tephra shard trace element ratios are comparable and complementary to the AVF whole rock database. The use of specific trace element ratios (e.g. Gd/Yb vs. Zr/Yb) allows us to fingerprint and cross correlate tephra horizons between cores and, when coupled with newly acquired 40Ar-39Ar age dating and eruption size estimates, correlate horizons to their source centres. This integrated style of study can provide valuable information to help volcanic hazard management and forecasting, and mitigation of related risks.

  4. Chemical characterization, nano-particle mineralogy and particle size distribution of basalt dust wastes

    Energy Technology Data Exchange (ETDEWEB)

    Dalmora, Adilson C. [Laboratory of Environmental Researches and Nanotechnology Development, Centro Universitário La Salle, Mestrado em Avaliação de Impactos Ambientais em Mineração. Victor Barreto, 2288 Centro 92010-000, Canoas, RS (Brazil); Institute for Environmental Assessment and Water Studies (IDÆA), Spanish National Research Council (CSIC), C/Jordi Girona 18-26, 08034 Barcelona (Spain); Ramos, Claudete G.; Oliveira, Marcos L.S. [Laboratory of Environmental Researches and Nanotechnology Development, Centro Universitário La Salle, Mestrado em Avaliação de Impactos Ambientais em Mineração. Victor Barreto, 2288 Centro 92010-000, Canoas, RS (Brazil); Teixeira, Elba C. [Fundação Estadual de Proteção Ambiental Henrique Luis Roessler, Porto Alegre, RS (Brazil); Kautzmann, Rubens M.; Taffarel, Silvio R. [Laboratory of Environmental Researches and Nanotechnology Development, Centro Universitário La Salle, Mestrado em Avaliação de Impactos Ambientais em Mineração. Victor Barreto, 2288 Centro 92010-000, Canoas, RS (Brazil); Brum, Irineu A.S. de [Universidade Federal do Rio Grande do Sul, Escola de Engenharia, Departamento de Metalurgia, Centro de Tecnologia, Av. Bento Gonçalves, 9500. Bairro Agronomia. CEP: 91501-970 Porto Alegre, RS (Brazil); and others

    2016-01-01

    Understanding the geochemistry of basalt alteration is central to the study of agriculture systems. Various nano-minerals play an important role in the mobilization of contaminants and their subsequent uptake by plants. We present a new analytical experimental approach in combination with an integrated analytical protocol designed to study basalt alteration processes. Recently, throughout the world, ultra-fine and nano-particles derived from basalt dust wastes (BDW) during “stonemeal” soil fertilizer application have been of great concern for their possible adverse effects on human health and environmental pollution. Samples of BDW utilized were obtained from companies in the Nova Prata mining district in southern Brazil for chemical characterization and nano-mineralogy investigation, using an integrated application of advanced characterization techniques such as X-ray diffraction (XRD), High Resolution-Transmission Electron microscopy (HR-TEM)/Energy Dispersive Spectroscopy (EDS)/(selected-area diffraction pattern) SAED, Field Emission-Scanning Electron Microscopy (FE-SEM/EDS), and granulometric distribution analysis. The investigation has revealed that BDW materials are dominated by SiO{sub 2}, Al{sub 2}O{sub 3}, and Fe{sub 2}O{sub 3,} with a complex micromineralogy including alkali feldspar, augite, barite, labradorite, hematite, heulandrite, gypsum, kaolinite, quartz, and smectite. In addition, we have identified a number of trace metals such as Cd, Cu, Cr, and Zn, that are preferentially concentrated into the finer, inhalable, dust fraction and, thus, could present a health hazard in the urban areas around the basalt mining zone. The implication of this observation is that use of these nanometric-sized particulates as soil fertilizer may present different health challenges to those of conventional fertilizers, inviting future work regarding the relative toxicities of these materials. Our investigation on the particle size distribution, nano

  5. Chemical characterization, nano-particle mineralogy and particle size distribution of basalt dust wastes

    International Nuclear Information System (INIS)

    Dalmora, Adilson C.; Ramos, Claudete G.; Oliveira, Marcos L.S.; Teixeira, Elba C.; Kautzmann, Rubens M.; Taffarel, Silvio R.; Brum, Irineu A.S. de

    2016-01-01

    Understanding the geochemistry of basalt alteration is central to the study of agriculture systems. Various nano-minerals play an important role in the mobilization of contaminants and their subsequent uptake by plants. We present a new analytical experimental approach in combination with an integrated analytical protocol designed to study basalt alteration processes. Recently, throughout the world, ultra-fine and nano-particles derived from basalt dust wastes (BDW) during “stonemeal” soil fertilizer application have been of great concern for their possible adverse effects on human health and environmental pollution. Samples of BDW utilized were obtained from companies in the Nova Prata mining district in southern Brazil for chemical characterization and nano-mineralogy investigation, using an integrated application of advanced characterization techniques such as X-ray diffraction (XRD), High Resolution-Transmission Electron microscopy (HR-TEM)/Energy Dispersive Spectroscopy (EDS)/(selected-area diffraction pattern) SAED, Field Emission-Scanning Electron Microscopy (FE-SEM/EDS), and granulometric distribution analysis. The investigation has revealed that BDW materials are dominated by SiO 2 , Al 2 O 3 , and Fe 2 O 3, with a complex micromineralogy including alkali feldspar, augite, barite, labradorite, hematite, heulandrite, gypsum, kaolinite, quartz, and smectite. In addition, we have identified a number of trace metals such as Cd, Cu, Cr, and Zn, that are preferentially concentrated into the finer, inhalable, dust fraction and, thus, could present a health hazard in the urban areas around the basalt mining zone. The implication of this observation is that use of these nanometric-sized particulates as soil fertilizer may present different health challenges to those of conventional fertilizers, inviting future work regarding the relative toxicities of these materials. Our investigation on the particle size distribution, nano-particle mineralogy and chemical

  6. Crystal Stratigraphy of Two Basalts from Apollo 16: Unique Crystallization of Picritic Basalt 606063,10-16 and Very-Low-Titanium Basalt 65703,9-13

    Science.gov (United States)

    Donohue, P. H.; Neal, C. R.; Stevens, R. E.; Zeigler, R. A.

    2014-01-01

    A geochemical survey of Apollo 16 regolith fragments found five basaltic samples from among hundreds of 2-4 mm regolith fragments of the Apollo 16 site. These included a high-Ti vitrophyric basalt (60603,10-16) and one very-low-titanium (VLT) crystalline basalt (65703,9-13). Apollo 16 was the only highlands sample return mission distant from the maria (approx. 200 km). Identification of basaltic samples at the site not from the ancient regolith breccia indicates input of material via lateral transport by post-basin impacts. The presence of basaltic rocklets and glass at the site is not unprecedented and is required to satisfy mass-balance constraints of regolith compositions. However, preliminary characterization of olivine and plagioclase crystal size distributions indicated the sample textures were distinct from other known mare basalts, and instead had affinities to impact melt textures. Impact melt textures can appear qualitatively similar to pristine basalts, and quantitative analysis is required to distinguish between the two in thin section. The crystal stratigraphy method is a powerful tool in studying of igneous systems, utilizing geochemical analyses across minerals and textural analyses of phases. In particular, trace element signatures can aid in determining the ultimate origin of these samples and variations document subtle changes occurring during their petrogenesis.

  7. Lunar Mare Basalts as Analogues for Martian Volcanic Compositions: Evidence from Visible, Near-IR, and Thermal Emission Spectroscopy

    Science.gov (United States)

    Graff, T. G.; Morris, R. V.; Christensen, P. R.

    2003-01-01

    The lunar mare basalts potentially provide a unique sample suite for understanding the nature of basalts on the martian surface. Our current knowledge of the mineralogical and chemical composition of the basaltic material on Mars comes from studies of the basaltic martian meteorites and from orbital and surface remote sensing observations. Petrographic observations of basaltic martian meteorites (e.g., Shergotty, Zagami, and EETA79001) show that the dominant phases are pyroxene (primarily pigeonite and augite), maskelynite (a diaplectic glass formed from plagioclase by shock), and olivine [1,2]. Pigeonite, a low calcium pyroxene, is generally not found in abundance in terrestrial basalts, but does often occur on the Moon [3]. Lunar samples thus provide a means to examine a variety of pigeonite-rich basalts that also have bulk elemental compositions (particularly low-Ti Apollo 15 mare basalts) that are comparable to basaltic SNC meteorites [4,5]. Furthermore, lunar basalts may be mineralogically better suited as analogues of the martian surface basalts than the basaltic martian meteorites because the plagioclase feldspar in the basaltic Martian meteorites, but not in the lunar surface basalts, is largely present as maskelynite [1,2]. Analysis of lunar mare basalts my also lead to additional endmember spectra for spectral libraries. This is particularly important analysis of martian thermal emission spectra, because the spectral library apparently contains a single pigeonite spectrum derived from a synthetic sample [6].

  8. Textures and mineral compositions of the Xinjie layered intrusion, SW China: Implications for the origin of magnetite and fractionation process of Fe-Ti-rich basaltic magmas

    Directory of Open Access Journals (Sweden)

    Huan Dong

    2013-09-01

    Full Text Available The Xinjie layered intrusion in the Panxi region, SW China, hosts both Fe-Ti oxide and platinum-group element (PGE sulfide mineralization. The intrusion can be divided, from the base upward, into Units I, II and III, in terms of mineral assemblages. Units I and II are mainly composed of wehrlite and clinopyroxenite, whereas Unit III is mainly composed of gabbro. PGE sulfide-rich layers mainly occur in Unit I, whereas thick Fe-Ti oxide-rich layers mainly occur in Unit III. An ilmenite-rich layer occurs at the top of Unit I. Fe-Ti oxides include magnetite and ilmenite. Small amounts of cumulus and intercumulus magnetite occur in Units I and II. Cumulus magnetite grains are commonly euhedral and enclosed within olivine and clinopyroxene. They have high Cr2O3 contents ranging from 6.02 to 22.5 wt.%, indicating that they are likely an early crystallized phase from magmas. Intercumulus magnetite that usually displays ilmenite exsolution occupies the interstices between cumulus olivine crystals and coexists with interstitial clinopyroxene and plagioclase. Intercumulus magnetite has Cr2O3 ranging from 1.65 to 6.18 wt.%, lower than cumulus magnetite. The intercumulus magnetite may have crystallized from the trapped liquid. Large amounts of magnetite in Unit III contains Cr2O3 (<0.28 wt.% much lower than magnetite in Units I and II. The magnetite in Unit III is proposed to be accumulated from a Fe-Ti-rich melt. The Fe-Ti-rich melt is estimated to contain 35.9 wt.% of SiO2, 26.9 wt.% of FeOt, 8.2 wt.% of TiO2, 13.2 wt.% of CaO, 8.3 wt.% of MgO, 5.5 wt.% of Al2O3 and 1.0 wt.% of P2O5. The composition is comparable with the Fe-rich melts in the Skaergaard and Sept Iles intrusions. Paired non-reactive microstructures, granophyre pockets and ilmenite-rich intergrowths, are representative of Si-rich melt and Fe-Ti-rich melt, and are the direct evidence for the existence of an immiscible Fe-Ti-rich melt that formed from an evolved ferro-basaltic magma.

  9. Rheology and thermal budget of lunar basalts: an experimental study and its implications for rille formation of non-Newtonian lavas on the Moon

    Science.gov (United States)

    Sehlke, A.; Whittington, A. G.

    2015-12-01

    Sinuous lava channels are a characteristic feature observed on the Moon. Their formation is assumed to be due to a combination of mechanical and thermal erosion of the lava into the substrate during emplacement as surface channels, or due to collapsed subsurface lava tubes after the lava has evacuated. The viscosity (η) of the lava plays an important role, because it controls the volume flux of the emplaced lava that governs the mechanical and thermal erosion potential of the lava flow. Thermal properties, such as heat capacity (Cp) and latent heat of crystallization (ΔHcryst) are important parameters in order for the substrate to melt and causing thermal buffering during crystallization of the flowing lava. We experimentally studied the rheological evolution of analog lavas representing the KREEP terrain and high-Ti mare basalts during cooling and crystallization. We find that the two lavas behave very differently. High-Ti mare lava begins to crystallize around 1300 ºC with a viscosity of 8.6±0.6 Pa s and crystal content around 2 vol%. On cooling to 1169 ºC, the effective viscosity of the crystal-melt suspension is increased to only 538±33 Pa s (at a strain rate of 1 s-1) due to crystallization of 14±1 vol% blocky magnetite and acicular ulvöspinel-rich magnetite. The flow behavior of these suspensions depends on the strain rate, where flow curves below strain rates of 10 s-1show shear-thinning character, but resemble Bingham behavior at greater strain rates. In contrast, the KREEP lava crystallizes rapidly over a narrow temperature interval of ~ 30 degrees. The first crystals detected were ulvospinel-rich magnetites at 1204 ºC with ~2 vol% and a viscosity of 90±2 Pa s. On cooling to 1178 ºC, anorthite and enstatite appears, so that the crystal-melt suspension has become strongly pseudoplastic at a crystal content of 22±2 vol% with a flow index (n) of 0.63 and an effective viscosity of 1600±222 Pa s at a strain rate of 1 s-1. We are currently measuring

  10. Engineered barrier development for a nuclear waste repository in basalt

    International Nuclear Information System (INIS)

    Smith, M.J.

    1980-05-01

    The BWIP Engineered Barrier Program has been developed to provide an integrated approach to the development of site-specific Engineered Barrier assemblages for a repository located in basalt. The goal of this program is to specify engineered and natural barriers which will ensure that nuclear and non-radioactive hazardous materials emplaced in a repository in basalt do not exceed acceptable rates of release to the biosphere. A wide range of analytical and experimental activities related to the basalt repository environment, waste package environment, waste/barrier/rock interactions, and barrier performance assessment provide the basis for selection of systems capable of meeting licensing requirements. Work has concentrated on specifying and testing natural and man-made materials which can be used to plug boreholes in basalt and which can be used as multiple barriers to surround nuclear waste forms and containers. The Engineered Barriers Program is divided into two major activities: multiple barrier studies and borehole plugging. 8 figures, 4 tables

  11. The hardness of synthetic products obtained from cooled and crystallized basaltic melts (in Romanian)

    OpenAIRE

    Daniela Ogrean

    2001-01-01

    The Hardness of Synthetic Products Obtained from Cooled and Crystallized Basaltic Melts. Hardness is one of the main properties of the products obtained from cooled and crystallized basaltic melts under a controlled thermal regime. It influences the abrasion tear resistance of the resulted material. The microhardness measurements on the samples (bricks, boards, gutters, armour plates, tubes) indicated Vickers hardness value between 757–926 for the materials obtained from Şanovita basalts (Tim...

  12. Potential for microbial oxidation of ferrous iron in basaltic glass.

    Science.gov (United States)

    Xiong, Mai Yia; Shelobolina, Evgenya S; Roden, Eric E

    2015-05-01

    Basaltic glass (BG) is an amorphous ferrous iron [Fe(II)]-containing material present in basaltic rocks, which are abundant on rocky planets such as Earth and Mars. Previous research has suggested that Fe(II) in BG can serve as an energy source for chemolithotrophic microbial metabolism, which has important ramifications for potential past and present microbial life on Mars. However, to date there has been no direct demonstration of microbially catalyzed oxidation of Fe(II) in BG. In this study, three different culture systems were used to investigate the potential for microbial oxidation of Fe(II) in BG, including (1) the chemolithoautotrophic Fe(II)-oxidizing, nitrate-reducing "Straub culture"; (2) the mixotrophic Fe(II)-oxidizing, nitrate-reducing organism Desulfitobacterium frappieri strain G2; and (3) indigenous microorganisms from a streambed Fe seep in Wisconsin. The BG employed consisted of clay and silt-sized particles of freshly quenched lava from the TEB flow in Kilauea, Hawaii. Soluble Fe(II) or chemically reduced NAu-2 smectite (RS) were employed as positive controls to verify Fe(II) oxidation activity in the culture systems. All three systems demonstrated oxidation of soluble Fe(II) and/or structural Fe(II) in RS, whereas no oxidation of Fe(II) in BG material was observed. The inability of the Straub culture to oxidize Fe(II) in BG was particularly surprising, as this culture can oxidize other insoluble Fe(II)-bearing minerals such as biotite, magnetite, and siderite. Although the reason for the resistance of the BG toward enzymatic oxidation remains unknown, it seems possible that the absence of distinct crystal faces or edge sites in the amorphous glass renders the material resistant to such attack. These findings have implications with regard to the idea that Fe(II)-Si-rich phases in basalt rocks could provide a basis for chemolithotrophic microbial life on Mars, specifically in neutral-pH environments where acid-promoted mineral dissolution and

  13. Moessbauer Studies of Volhynian Basalts

    International Nuclear Information System (INIS)

    Bakun-Czubarow, N.; Milczarski, J.; Galazka-Friedman, J.; Szlachta, K.; Forder, S.

    2011-01-01

    The Volhynian basalts studied belong to the effusive-tuffogenic Volhynian Series (Slawatycze Series in Poland), being the large Ediacaran continental igneous province, that covers an area of 200 000 km 2 in the western margin of East European Craton. The series is underlain by the Cryogenian terrigenous Polesie Series with doleritic sills and dikes. The Volhynian Series consists of the rock beds belonging to the three volcanic cycles with different ratios of flood basalts to pyroclastics. The aim of the study was recognition of primary and secondary Fe-bearing minerals, particularly Fe- and Fe-Ti oxides as well as determination of iron oxidation state, that is an important tool in the search for native copper deposits in these rocks. For Moessbauer studies the following rock samples were chosen: the Polesie Series dolerites, the Volhynian Series basalts from the Ukrainian quarries and drill-holes, e.g. from the Volodymir Volhynskaya drilling hole; the Slawatycze Series basalts from Kaplonosy drill-hole in Poland. In the Kaplonosy basalts the content of magnetite decreases with depth, which may be caused by magma differentiation due to fractional crystallization, when Mg content decreases as Ti and Fe - increases in basic magma. In the Kaplonosy basalts the Fe 2+ /Fe 3+ ratio increases with depth, which points to the increase of iron oxidation with the progress of basaltic magma differentiation. (authors)

  14. Chemical characterization, nano-particle mineralogy and particle size distribution of basalt dust wastes.

    Science.gov (United States)

    Dalmora, Adilson C; Ramos, Claudete G; Oliveira, Marcos L S; Teixeira, Elba C; Kautzmann, Rubens M; Taffarel, Silvio R; de Brum, Irineu A S; Silva, Luis F O

    2016-01-01

    Understanding the geochemistry of basalt alteration is central to the study of agriculture systems. Various nano-minerals play an important role in the mobilization of contaminants and their subsequent uptake by plants. We present a new analytical experimental approach in combination with an integrated analytical protocol designed to study basalt alteration processes. Recently, throughout the world, ultra-fine and nano-particles derived from basalt dust wastes (BDW) during "stonemeal" soil fertilizer application have been of great concern for their possible adverse effects on human health and environmental pollution. Samples of BDW utilized were obtained from companies in the Nova Prata mining district in southern Brazil for chemical characterization and nano-mineralogy investigation, using an integrated application of advanced characterization techniques such as X-ray diffraction (XRD), High Resolution-Transmission Electron microscopy (HR-TEM)/Energy Dispersive Spectroscopy (EDS)/(selected-area diffraction pattern) SAED, Field Emission-Scanning Electron Microscopy (FE-SEM/EDS), and granulometric distribution analysis. The investigation has revealed that BDW materials are dominated by SiO2, Al2O3, and Fe2O3, with a complex micromineralogy including alkali feldspar, augite, barite, labradorite, hematite, heulandrite, gypsum, kaolinite, quartz, and smectite. In addition, we have identified a number of trace metals such as Cd, Cu, Cr, and Zn, that are preferentially concentrated into the finer, inhalable, dust fraction and, thus, could present a health hazard in the urban areas around the basalt mining zone. The implication of this observation is that use of these nanometric-sized particulates as soil fertilizer may present different health challenges to those of conventional fertilizers, inviting future work regarding the relative toxicities of these materials. Our investigation on the particle size distribution, nano-particle mineralogy and chemical composition in

  15. 'Memristive' switches enable 'stateful' logic operations via material implication.

    Science.gov (United States)

    Borghetti, Julien; Snider, Gregory S; Kuekes, Philip J; Yang, J Joshua; Stewart, Duncan R; Williams, R Stanley

    2010-04-08

    The authors of the International Technology Roadmap for Semiconductors-the industry consensus set of goals established for advancing silicon integrated circuit technology-have challenged the computing research community to find new physical state variables (other than charge or voltage), new devices, and new architectures that offer memory and logic functions beyond those available with standard transistors. Recently, ultra-dense resistive memory arrays built from various two-terminal semiconductor or insulator thin film devices have been demonstrated. Among these, bipolar voltage-actuated switches have been identified as physical realizations of 'memristors' or memristive devices, combining the electrical properties of a memory element and a resistor. Such devices were first hypothesized by Chua in 1971 (ref. 15), and are characterized by one or more state variables that define the resistance of the switch depending upon its voltage history. Here we show that this family of nonlinear dynamical memory devices can also be used for logic operations: we demonstrate that they can execute material implication (IMP), which is a fundamental Boolean logic operation on two variables p and q such that pIMPq is equivalent to (NOTp)ORq. Incorporated within an appropriate circuit, memristive switches can thus perform 'stateful' logic operations for which the same devices serve simultaneously as gates (logic) and latches (memory) that use resistance instead of voltage or charge as the physical state variable.

  16. Nature and composition of interbedded marine basaltic pumice in ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Earth System Science; Volume 126; Issue 2. Nature and composition of interbedded marine basaltic pumice in the ~52–50 Ma Vastan lignite sequence, western India: Implication for Early Eocene MORB volcanism offshore Arabian Sea. Sarajit Sensarma Hukam Singh R S Rana Debajyoti Paul ...

  17. Nature and composition of interbedded marine basaltic pumice in the

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Earth System Science; Volume 126; Issue 2. Nature and composition of interbedded marine basaltic pumice in the ~52–50 Ma Vastan lignite sequence, western India: Implication for Early Eocene MORB volcanism offshore Arabian Sea. Sarajit Sensarma Hukam Singh R S Rana Debajyoti Paul ...

  18. Additive Construction using Basalt Regolith Fines

    Science.gov (United States)

    Mueller, Robert P.; Sibille, Laurent; Hintze, Paul E.; Lippitt, Thomas C.; Mantovani, James G.; Nugent, Matthew W.; Townsend, Ivan I.

    2014-01-01

    Planetary surfaces are often covered in regolith (crushed rock), whose geologic origin is largely basalt. The lunar surface is made of small-particulate regolith and areas of boulders located in the vicinity of craters. Regolith composition also varies with location, reflecting the local bedrock geology and the nature and efficiency of the micrometeorite-impact processes. In the lowland mare areas (suitable for habitation), the regolith is composed of small granules (20 - 100 microns average size) of mare basalt and volcanic glass. Impacting micrometeorites may cause local melting, and the formation of larger glassy particles, and this regolith may contain 10-80% glass. Studies of lunar regolith are traditionally conducted with lunar regolith simulant (reconstructed soil with compositions patterned after the lunar samples returned by Apollo). The NASA Kennedy Space Center (KSC) Granular Mechanics & Regolith Operations (GMRO) lab has identified a low fidelity but economical geo-technical simulant designated as Black Point-1 (BP-1). It was found at the site of the Arizona Desert Research and Technology Studies (RATS) analog field test site at the Black Point lava flow in adjacent basalt quarry spoil mounds. This paper summarizes activities at KSC regarding the utilization of BP-1 basalt regolith and comparative work with lunar basalt simulant JSC-1A as a building material for robotic additive construction of large structures. In an effort to reduce the import or in-situ fabrication of binder additives, we focused this work on in-situ processing of regolith for construction in a single-step process after its excavation. High-temperature melting of regolith involves techniques used in glassmaking and casting (with melts of lower density and higher viscosity than those of metals), producing basaltic glass with high durability and low abrasive wear. Most Lunar simulants melt at temperatures above 1100 C, although melt processing of terrestrial regolith at 1500 C is not

  19. Corrosion phase formation on container alloys in basalt repository environments

    International Nuclear Information System (INIS)

    Johnston, R.G.; Anantatmula, R.P.; Lutton, J.M.; Rivera, C.L.

    1986-01-01

    The Basalt Waste Isolation Project is evaluating the suitability of basalt in southeastern Washington State as a possible location for a nuclear waste repository. The performance of the waste package, which includes the waste form, container, and surrounding packing material, will be affected by the stability of container alloys in the repository environment. Primary corrosion phases and altered packing material containing metals leached from the container may also influence subsequent reactions between the waste form and repository environment. Copper- and iron-based alloys were tested at 50 0 to 300 0 C in an air/steam environment and in pressure vessels in ground-water-saturated basalt-bentonite packing material. Reaction phases formed on the alloys were identified and corrosion rates were measured. Changes in adhering packing material were also evaluated. The observed reactions and their possible effects on container alloy durability in the repository are discussed

  20. Mantle dynamics and basalt petrogenesis

    Science.gov (United States)

    Ringwood, A. E.

    1985-03-01

    Differentiation at mid-ocean ridges generates a layered lithosphere consisting of a basaltic crust, immediately underlain by harzburgite and further underlain by pyrolite which has experienced depletion only of highly incompatible elements. The body forces driving subduction are concentrated mainly in the upper half of the lithosphere which is relatively cool and brittle. During subduction, the lower layer of relatively ductile, slightly depleted pyrolite is stripped off and resorbed into the upper mantle, thereby providing a future source region for MORB magmas. The slab which sinks to ~ 600 km is comprised mainly of differentiated former basalt and harzburgite which undergo a different series of phase transformations to those experienced by mantle pyrolite. In consequence, the former basaltic crust remains denser than surrounding mantle whereas former harzburgite becomes relatively buoyant below the 650 km seismic discontinuity. The resulting non-uniformity in stress distribution causes the slab to buckle at this depth and accrete to form a large, relatively cool ovoid "megalith" of mixed former harzburgite and basaltic crust. Heating of the megalith occurs over 1-2 b.y., leading to partial melting of the former basaltic crust. The resultant liquids contaminate regions of former harzburgite, rendering them fertile in the sense of future capacity to produce basaltic magmas. After thermal equilibration, the newly fertile, former harzburgite becomes buoyant, leading to the separation of diapirs which rise into the upper mantle. Such diapirs rising beneath sub-oceanic lithosphere experience small degrees of partial melting to produce ocean island basalts, mainly of the alkaline suite. Diapirs of fertile former harzburgite rising beneath continents become incorporated into the sub-continental lithosphere. This is a cumulative process and is ultimately responsible for the development of the chemical, physical and isotopic characteristics of the sub

  1. New high pressure experiments on sulfide saturation of high-FeO∗ basalts with variable TiO2 contents - Implications for the sulfur inventory of the lunar interior

    Science.gov (United States)

    Ding, Shuo; Hough, Taylor; Dasgupta, Rajdeep

    2018-02-01

    In order to constrain sulfur concentration in intermediate to high-Ti mare basalts at sulfide saturation (SCSS), we experimentally equilibrated FeS melt and basaltic melt using a piston cylinder at 1.0-2.5 GPa and 1400-1600 °C, with two silicate compositions similar to high-Ti (Apollo 11: A11, ∼11.1 wt.% TiO2, 19.1 wt.% FeO∗, and 39.6 wt.% SiO2) and intermediate-Ti (Luna 16, ∼5 wt.% TiO2, 18.7 wt.% FeO∗, and 43.8 wt.% SiO2) mare basalts. Our experimental results show that SCSS increases with increasing temperature, and decreases with increasing pressure, which are similar to the results from previous experimental studies. SCSS in the A11 melt is systematically higher than that in the Luna 16 melt, which is likely due to higher FeO∗, and lower SiO2 and Al2O3 concentration in the former. Compared to the previously constructed SCSS models, including those designed for high-FeO∗ basalts, the SCSS values determined in this study are generally lower than the predicted values, with overprediction increasing with increasing melt TiO2 content. We attribute this to the lower SiO2 and Al2O3 concentration of the lunar magmas, which is beyond the calibration range of previous SCSS models, and also more abundant FeTiO3 complexes in our experimental melts that have higher TiO2 contents than previous models' calibration range. The formation of FeTiO3 complexes lowers the activity of FeO∗, aFeO∗silicate melt , and therefore causes SCSS to decrease. To accommodate the unique lunar compositions, we have fitted a new SCSS model for basaltic melts of >5 wt.% FeO∗ and variable TiO2 contents. Using previous chalcophile element partitioning experiments that contained more complex Fe-Ni-S sulfide melts, we also derived an empirical correction that allows SCSS calculation for basalts where the equilibrium sulfides contain variable Ni contents of 10-50 wt.%. At the pressures and temperatures of multiple saturation points, SCSS of lunar magmas with compositions from

  2. Giant Plagioclase Basalts, eruption rate versus time

    Indian Academy of Sciences (India)

    R.Narasimhan(krishtel emaging) 1461 1996 Oct 15 13:05:22

    can traps; Earth Planet. Sci. Lett. 180 13–27. Hooper P R and others 1988 The Giant Plagioclase Basalts. (GPBs) of the Western Ghats, Deccan Traps; Mem. Geol. Soc. India 43 153–65. Khadri S F R and 3 others 1988 Stratigraphy of Thakurvadi. Formation, Western Deccan Basalt Province, India: In. Deccan Flood Basalts ...

  3. Effect of Moisture Absorption Behavior on Mechanical Properties of Basalt Fibre Reinforced Polymer Matrix Composites

    Directory of Open Access Journals (Sweden)

    Amuthakkannan Pandian

    2014-01-01

    Full Text Available The study of mechanical properties of fibre reinforced polymeric materials under different environmental conditions is much important. This is because materials with superior ageing resistance can be satisfactorily durable. Moisture effects in fibre reinforced plastic composites have been widely studied. Basalt fibre reinforced unsaturated polyester resin composites were subjected to water immersion tests using both sea and normal water in order to study the effects of water absorption behavior on mechanical properties. Composites specimens containing woven basalt, short basalt, and alkaline and acid treated basalt fibres were prepared. Water absorption tests were conducted by immersing specimens in water at room temperature for different time periods till they reached their saturation state. The tensile, flexural, and impact properties of water immersed specimens were conducted and compared with dry specimens as per the ASTM standard. It is concluded that the water uptake of basalt fibre is considerable loss in the mechanical properties of the composites.

  4. Implications for the management of R A materials transport

    International Nuclear Information System (INIS)

    Devine, I.R.

    1997-01-01

    This paper attempts to describe some Exclusions and Exemptions from the current and proposed transport regulations and describes those requirements applicable to low active material. It concludes that Clearance is the dominant issue and that within the UK nuclear sector, the current (1985 as amended 1990) transport regulations have no significant impact on the management of low active materials. Nor will the proposed (1996) Regulations. (author)

  5. Implications of extraterrestrial material on the origin of life

    Science.gov (United States)

    Pasek, Matthew

    2015-08-01

    Stanley Miller's discovery of an abiotic organic synthesis relevant to the early earth provided a route to the scientific consideration of the origin of life. Since the 1950s, several thousands of experiments have shown that the precursor molecules to living biochemical systems could come about naturally. That these processes are active in the universe has been demonstrated by the detection of organic molecules in chondritic meteorites. Indeed, the very delivery of organics by extraterrestrial material may have been a viable source of important prebiotic molecules on the early earth. In this talk I will review the delivery of organics and other elements to the early earth, and will attempt to quantify the mass of material that might have been present from extraterrestrial sources on the early earth.The flux of prebiotic material on the early earth was influenced by the increase in delivery in the early history of the solar system, and by the sources available in the early solar system. Carbonaceous asteroids, comets, stony chondritic bodies, and differentiated asteroids each would have provided different materials to the early earth. The atmosphere would have provided a filter for some of this material, and the amount that reached the earth's surface would have depended on material strength, angle of entry, and atmospheric composition.Previously I reported that carbonaceous chondrites and micrometeorites would have provided a diffuse source of organic molecules on the early earth, whereas differentiated asteroids would have provided concentrated point sources for other materials, such as phosphorus (Pasek and Lauretta, Origins of Life and Evolution of Biospheres 2008). These results are reconsidered in the light of new ideas on the bombardment history of the early solar system, and with new considerations of the composition of source material that reached the earth.

  6. Potentials and policy implications of energy and material efficiency improvement

    Energy Technology Data Exchange (ETDEWEB)

    Worrell, Ernst; Levine, Mark; Price, Lynn; Martin, Nathan; van den Broek, Richard; Block, Kornelis

    1997-01-01

    There is a growing awareness of the serious problems associated with the provision of sufficient energy to meet human needs and to fuel economic growth world-wide. This has pointed to the need for energy and material efficiency, which would reduce air, water and thermal pollution, as well as waste production. Increasing energy and material efficiency also have the benefits of increased employment, improved balance of imports and exports, increased security of energy supply, and adopting environmentally advantageous energy supply. A large potential exists for energy savings through energy and material efficiency improvements. Technologies are not now, nor will they be, in the foreseeable future, the limiting factors with regard to continuing energy efficiency improvements. There are serious barriers to energy efficiency improvement, including unwillingness to invest, lack of available and accessible information, economic disincentives and organizational barriers. A wide range of policy instruments, as well as innovative approaches have been tried in some countries in order to achieve the desired energy efficiency approaches. These include: regulation and guidelines; economic instruments and incentives; voluntary agreements and actions, information, education and training; and research, development and demonstration. An area that requires particular attention is that of improved international co-operation to develop policy instruments and technologies to meet the needs of developing countries. Material efficiency has not received the attention that it deserves. Consequently, there is a dearth of data on the qualities and quantities for final consumption, thus, making it difficult to formulate policies. Available data, however, suggest that there is a large potential for improved use of many materials in industrialized countries.

  7. Investigation on mechanical properties of basalt composite fabrics (experiment study

    Directory of Open Access Journals (Sweden)

    Talebi Mazraehshahi H.

    2010-06-01

    Full Text Available To fully appreciate the role and application of composite materials to structures, correct understanding of mechanical behaviors required for selection of optimum material. Fabric reinforced composites are composed of a matrix that is reinforced with pliable fabric, glass fabric is most popular reinforcement for different application specially in aircraft structure, although other fabric material are also used. At this study new fabric material called basalt with epoxy resin introduced and mechanical behaviors of this material investigated from view point of testing. For this study two type of fabric with different thickness used. Comparison between this composite reinforcement with popular reinforcement as carbon, glass, kevlar performed. To determine mechanical properties of epoxy based basalt fabric following test procedure performed : 1. Tensile testing according to ASTM D3039 in 0° and 90° direction to find ultimate strength in tension and shear, modulus of elasticity, elangation and ultimate strain. 2. Compression testing according to EN 2850 ultimate compression strength and maximum deformation under compression loading. 3. Shear testing according to ASTM D3518-94 to find in plane shear response of polymer matrix composites materials. 4. Predict flexural properties of sandwich construction which manufactured from basalt facing with PVC foam core according to ASTM C393-94. Material strength properties must be based on enough tests of material to meet the test procedure specifications [1]. For this reason six specimens were manufactured for testing and the tests were performed on them using an INSTRON machine model 5582. In the study, the effect of percent of resin in basalt reinforced composite was investigated. Also the weights of the ballast based composites with different percent of resin were measured with conventional composites. As the weight is an important parameter in aerospace industry when the designer wants to replace one

  8. Investigation on mechanical properties of basalt composite fabrics (experiment study)

    Science.gov (United States)

    Talebi Mazraehshahi, H.; Zamani, H.

    2010-06-01

    To fully appreciate the role and application of composite materials to structures, correct understanding of mechanical behaviors required for selection of optimum material. Fabric reinforced composites are composed of a matrix that is reinforced with pliable fabric, glass fabric is most popular reinforcement for different application specially in aircraft structure, although other fabric material are also used. At this study new fabric material called basalt with epoxy resin introduced and mechanical behaviors of this material investigated from view point of testing. For this study two type of fabric with different thickness used. Comparison between this composite reinforcement with popular reinforcement as carbon, glass, kevlar performed. To determine mechanical properties of epoxy based basalt fabric following test procedure performed : 1). Tensile testing according to ASTM D3039 in 0° and 90° direction to find ultimate strength in tension and shear, modulus of elasticity, elangation and ultimate strain. 2). Compression testing according to EN 2850 ultimate compression strength and maximum deformation under compression loading. 3). Shear testing according to ASTM D3518-94 to find in plane shear response of polymer matrix composites materials. 4). Predict flexural properties of sandwich construction which manufactured from basalt facing with PVC foam core according to ASTM C393-94. Material strength properties must be based on enough tests of material to meet the test procedure specifications [1]. For this reason six specimens were manufactured for testing and the tests were performed on them using an INSTRON machine model 5582. In the study, the effect of percent of resin in basalt reinforced composite was investigated. Also the weights of the ballast based composites with different percent of resin were measured with conventional composites. As the weight is an important parameter in aerospace industry when the designer wants to replace one material with

  9. Flood basalts and extinction events

    Science.gov (United States)

    Stothers, Richard B.

    1993-01-01

    The largest known effusive eruptions during the Cenozoic and Mesozoic Eras, the voluminous flood basalts, have long been suspected as being associated with major extinctions of biotic species. Despite the possible errors attached to the dates in both time series of events, the significance level of the suspected correlation is found here to be 1 percent to 4 percent. Statistically, extinctions lag eruptions by a mean time interval that is indistinguishable from zero, being much less than the average residual derived from the correlation analysis. Oceanic flood basalts, however, must have had a different biological impact, which is still uncertain owing to the small number of known examples and differing physical factors. Although not all continental flood basalts can have produced major extinction events, the noncorrelating eruptions may have led to smaller marine extinction events that terminated at least some of the less catastrophically ending geologic stages. Consequently, the 26 Myr quasi-periodicity seen in major marine extinctions may be only a sampling effect, rather than a manifestation of underlying periodicity.

  10. Correlation between compressive strength and ultrasonic pulse velocity of high strength concrete incorporating chopped basalt fibre

    Science.gov (United States)

    Shafiq, Nasir; Fadhilnuruddin, Muhd; Elshekh, Ali Elheber Ahmed; Fathi, Ahmed

    2015-07-01

    Ultrasonic pulse velocity (UPV), is considered as the most important test for non-destructive techniques that are used to evaluate the mechanical characteristics of high strength concrete (HSC). The relationship between the compressive strength of HSC containing chopped basalt fibre stands (CBSF) and UPV was investigated. The concrete specimens were prepared using a different ratio of CBSF as internal strengthening materials. The compressive strength measurements were conducted at the sample ages of 3, 7, 28, 56 and 90 days; whilst, the ultrasonic pulse velocity was measured at 28 days. The result of HSC's compressive strength with the chopped basalt fibre did not show any improvement; instead, it was decreased. The UPV of the chopped basalt fibre reinforced concrete has been found to be less than that of the control mix for each addition ratio of the basalt fibre. A relationship plot is gained between the cube compressive strength for HSC and UPV with various amounts of chopped basalt fibres.

  11. Adsorption of albumin on prosthetic materials: implication for tribological behavior.

    Science.gov (United States)

    Serro, A P; Gispert, M P; Martins, M C L; Brogueira, P; Colaço, R; Saramago, B

    2006-09-01

    The orthopedic prosthesis used to substitute damaged natural joints are lubricated by a pseudosynovial fluid that contains biological macromolecules with potential boundary lubrication properties. Proteins are some of those macromolecules whose role in the lubrication process is not yet completely understood. In a previous work, we investigated the influence of the presence of albumin, the major synovial protein, upon the tribological behavior of three of the most used pairs of artificial joint materials: ultra high molecular weight polyethylene (UHMWPE) against counterfaces of alumina, CoCrMo alloy, and 316L stainless steel. Albumin was found to cause a significant decrease in the friction coefficient when the counterfaces were metallic because transfer of UHMWPE was avoided, but this effect was much weaker in the case of alumina. The objective of the present work was to look for an explanation for these differences in tribological behavior in terms of albumin adsorption. With this goal, studies on adsorption of bovine serum albumin (BSA) on the counterface materials, from a biological model fluid (Hanks' balanced salt solution), were carried out using radiolabeled albumin ((125)I-BSA), X-ray photoelectron spectroscopy, and atomic force microscopy. The conclusion from all techniques is that the driving force for albumin adsorption is higher on the metals than on alumina. These results confirm that the greater the amount of protein adsorbed on the counterface, the more efficient is the protection against the transfer of polymeric film to the counterface.

  12. Experimental study of the Mg and Sr isotopic evolution of seawater interacting with basalt between 150 and 300 ° C.

    Science.gov (United States)

    Voigt, Martin; Pearce, Christopher R.; Oelkers, Eric H.

    2016-04-01

    The chemical exchange of material between seawater and the oceanic crust plays a major role in marine geochemical cycles [1]. Isotopic signatures provide an important means of tracing elemental transfer in hydrothermal environments, yet only a limited amount of experimental data on the extent of isotopic fractionation under these conditions is currently available. This study consequently investigated the extent of δ26/24Mg and 87Sr/86Sr isotopic variation during a seawater-basalt interaction experiments at 150, 250 and 290 ° C. A suite of closed system experiments were run for several months at each temperature under saturated water pressure, using either crystalline or glassy basalt as the starting material and a water/rock ratio of 10 or 25. Our results demonstrate that the dissolution of basaltic material in hydrothermal environments occurs at the same time as the precipitation of alteration minerals (mainly smectite and anhydrite), which is consistent with results from similar studies in the past (e.g. [2]). As expected, the rate of reaction using crystalline basalt was slower than with basaltic glass, and both sample types reacted faster at higher temperatures. The 87Sr/86Sr composition of the experimental fluids decreased from the initial seawater value (0.70916) towards the lower basaltic signature during the experiments (0.70317), demonstrating the progressive release of Sr during basalt dissolution. Magnesium was steadily removed from the fluid via the precipitation of clay minerals, with the residual fluids having progressively lighter δ26/24Mg compositions. The mean Mg isotope fractionation factor (αsolid-solution) observed at 250 oC was 1.0005±0.0002, supporting low-temperature evidence that clay minerals preferentially incorporate isotopically heavy magnesium [3]. These experiments provide quantitative information on the extent of Mg isotopic fractionation between fluids and secondary silicate minerals in hydrothermal systems, and demonstrate the

  13. The investigation of gamma and neutron shielding properties of concrete including basalt fibre for nuclear energy applications

    International Nuclear Information System (INIS)

    Nulk, H.; Ipbuker, C.; Gulik, V.; Tkaczyk, A.; Biland, A.

    2015-01-01

    In this study, we would like to draw attention to the prospect of basalt fibre as the main component for concrete reinforcement of NPP. This work describes the computational study of gamma attenuation parameters, the effective atomic number Z(eff) and the effective electron density N e (eff), of relatively light-weight concrete with chopped basalt fibre used as reinforcement in different mixture rates. We can draw the following conclusions. Basalt fibre is a relatively cheap material that can be used as reinforcement instead of metallic fibers. Basalt fibre has a similar specific gravity to that of concrete elements. Basalt fibre has high chemical and abrasion resistance. Basalt fibre has almost 10 times the tensile strength of steel re-bars. Gamma-ray attenuation coefficients increase with addition of basalt fibre into concrete in every case. The effective atomic number of the concrete increases with the addition of basalt fibre. The results show that basalt fibre reinforced concrete have improved shielding properties against gamma rays in comparison with regular concrete. This result is based on a regular concrete with only basalt fiber reinforcement. We estimate that with addition of standard aggregates for radiation shielding concrete, such as barite, magnetite or hematite, the shielding properties will increase exponentially

  14. Automobile materials competition: energy implications of fiber-reinforced plastics

    Energy Technology Data Exchange (ETDEWEB)

    Cummings-Saxton, J.

    1981-10-01

    The embodied energy, structural weight, and transportation energy (fuel requirement) characteristics of steel, fiber-reinforced plastics, and aluminum were assessed to determine the overall energy savings of materials substitution in automobiles. In body panels, a 1.0-lb steel component with an associated 0.5 lb in secondary weight is structurally equivalent to a 0.6-lb fiber-reinforced plastic component with 0.3 lb in associated secondary weight or a 0.5-lb aluminum component with 0.25 lb of secondary weight. (Secondary weight refers to the combined weight of the vehicle's support structure, engine, braking system, and drive train, all of which can be reduced in response to a decrease in total vehicle weight.) The life cycle transportation energy requirements of structurally equivalent body panels (including their associated secondary weights) are 174.4 x 10/sup 3/ Btu for steel, 104.6 x 10/sup 3/ Btu for fiber-reinforced plastics, and 87.2 x 10/sup 3/ Btu for aluminum. The embodied energy requirements are 37.2 x 10/sup 3/ Btu for steel, 22.1 x 10/sup 3/ Btu for fiber-reinforced plastics, and 87.1 x 10/sup 3/ Btu for aluminum. These results can be combined to yield total energy requirements of 211.6 x 10/sup 3/ Btu for steel, 126.7 x 10/sup 3/ Btu for fiber-reinforced plastics, and 174.3 x 10/sup 3/ Btu for aluminum. Fiber-reinforced plastics offer the greatest improvements over steel in both embodied and total energy requirements. Aluminum achieves the greatest savings in transportation energy.

  15. Intracanyon basalt lavas of the Debed River (northern Armenia), part of a Pliocene-Pleistocene continental flood basalt province in the South Caucasus

    Science.gov (United States)

    Sheth, Hetu; Meliksetian, Khachatur; Gevorgyan, Hripsime; Israyelyan, Arsen; Navasardyan, Gevorg

    2015-03-01

    Late Pliocene to Early Pleistocene (~ 3.25-2.05 Ma), 200-400 m thick basalt lavas outcrop in the South Caucasus region, including the Kars-Erzurum Plateau (northeastern Turkey), the Javakheti Plateau (Georgia-Armenia), and the Lori Plateau (northern Armenia). These fissure-fed, rapidly erupted fluid lavas filled pre-existing river valleys over many tens of kilometres. The basalts exposed in the Debed River canyon, northern Armenia, are ~ 200 m thick and of three morphological types: (1) basal pillow basalts and hyaloclastites, overlain by (2) columnar-jointed pahoehoe sheet flows, in turn overlain by (3) slabby pahoehoe and rubbly pahoehoe flows. The lower and middle lavas show evidence for damming of river drainage, like many lavas of the Columbia River flood basalt province, Scotland, Ireland, and Iceland. There is also evidence for syn-volcanic faulting of the early lavas. Related basalts also outcrop in the Gegham Uplands and the Hrazdan River basin in Armenia. This 3.25-2.05 Ma South Caucasus basalt province, covering parts of Turkey, Georgia and Armenia, has an estimated areal extent of ~ 15,000 km2 and volume of ~ 2250 km3. Because its main geological features are remarkably like those of many continental flood basalt (CFB) provinces, we consider it a true, albeit small, CFB province. It is the smallest and youngest CFB in the world. An analogue closely similar in major features is the Late Miocene Altos de Jalisco CFB province in the western Trans-Mexican Volcanic Belt. Both provinces formed during lithospheric pull-apart and transtensional faulting. Their broader significance is in showing flood basalt size distribution to be a continuum without natural breaks, with implications for geodynamic models.

  16. Flame-resistant pure and hybrid woven fabrics from basalt

    Science.gov (United States)

    Jamshaid, H.; Mishra, R.; Militky, J.

    2017-10-01

    This work has been formulated to investigate the burning behavior of different type of fabrics. The main concentration is to see how long the fabric resists after it catches the fire and the propagation of fire can be reduced by using flame resistant fiber i.e basalt. Basalt fiber is an environmental friendly material with low input, high output, low energy consumption and less emission. The goal of present investigations is to show the dependence of fabric flammability on its structure parameters i.e weave type, blend type etc. Fabric weaves have strong effect on flammability properties. Plain weave has the lowest burning rate as the density of the plain weave fabric is more and the structure is tight which gives less chances of flame passing through the fabric. Thermal stability is evaluated with TGA of all hybrid and nonhybrid fabrics and compared. The thermal stability of the basalt fiber is excellent. When comparing thermal analysis curves for hybrid samples it demonstrates that thermal stability of the samples containing basalt is much higher than the non- hybrid samples. Percentage weight loss is less in hybrid samples as compared to non-hybrid samples. The effectiveness of hybridization on samples may be indicated by substantial lowering of the decomposition mass. Correlation was made between flammability with the infrared radiations (IR)

  17. Nature and composition of interbedded marine basaltic pumice in the ˜52-50 Ma Vastan lignite sequence, western India: Implication for Early Eocene MORB volcanism offshore Arabian Sea

    Science.gov (United States)

    Sensarma, Sarajit; Singh, Hukam; Rana, R. S.; Paul, Debajyoti; Sahni, Ashok

    2017-03-01

    The recognition of pyroclasts preserved in sedimentary environments far from its source is uncommon. We here describe occurrences of several centimetres-thick discontinuous basaltic pumice lenses occurring within the Early Eocene Vastan lignite mine sedimentary sequence, western India at two different levels - one at ˜5 m and the other at 10 m above a biostratigraphically constrained 52 Ma old marker level postdating the Deccan Volcanism. These sections have received global attention as they record mammalian and plant radiations. We infer the repetitive occurrence of pumice have been sourced from a ˜52-50 Ma MORB related to sea-floor spreading in the western Arabian Sea, most plausibly along the Carlsberg Ridge. Pyroclasts have skeletal plagioclase with horsetail morphologies ± pyroxene ± Fe-Ti oxide euhedral crystals, and typically comprise of circular polymodal (radii ≤10 to ≥30 μm), non-coalescing microvesicles (>40-60%). The pumice have undergone considerable syngenetic alteration during oceanic transport and post-burial digenesis, and are a composite mixture of Fe-Mn-rich clay and hydrated altered basaltic glass (palagonite). The Fe-Mn-rich clay is extremely low in SiO 2, Al 2 O 3, TiO 2, MgO, alkalies and REE, but very high in Fe 2 O 3, MnO, P, Ba, Sr contents, and palagonitization involved significant loss of SiO 2, Al 2 O 3, MgO and variable gain in Fe 2 O 3, TiO 2, Ni, V, Zr, Zn and REE. Bubble initiation to growth in the ascending basaltic magma (liquidus ˜1200-1250 ∘C) may have occured in ˜3 hr. Short-distance transport, non-connected vesicles, deposition in inner shelf to more confined lagoonal condition in the Early Eocene and quick burial helped preservation of the pumice in Vastan. Early Eocene Arabian Sea volcanism thus might have been an additional source to marginal sediments along the passive margin of western India.

  18. The hardness of synthetic products obtained from cooled and crystallized basaltic melts (in Romanian

    Directory of Open Access Journals (Sweden)

    Daniela Ogrean

    2001-04-01

    Full Text Available The Hardness of Synthetic Products Obtained from Cooled and Crystallized Basaltic Melts. Hardness is one of the main properties of the products obtained from cooled and crystallized basaltic melts under a controlled thermal regime. It influences the abrasion tear resistance of the resulted material. The microhardness measurements on the samples (bricks, boards, gutters, armour plates, tubes indicated Vickers hardness value between 757–926 for the materials obtained from Şanovita basalts (Timiş district and between 539–958 respectively, in case of the Racoş basalts (Braşov district. There is a certain variation of the hardness within the same sample, in various measurement points, within the theoretical limits of the hardnesses of the pyroxenes and that of the spinels.

  19. Magnesium-rich Basalts on Mercury

    Science.gov (United States)

    Martel, L. M. V.

    2013-05-01

    X-ray and gamma-ray spectrometers on NASA's MESSENGER spacecraft are making key measurements regarding the composition and properties of the surface of Mercury, allowing researchers to more clearly decipher the planet's formation and geologic history. The origin of the igneous rocks in the crust of Mercury is the focus of recent research by Karen Stockstill-Cahill and Tim McCoy (National Museum of Natural History, Smithsonian Institution), along with Larry Nittler and Shoshana Weider (Carnegie Institution of Washington) and Steven Hauck II (Case Western Reserve University). Using the well-known MELTS computer code Stockstill-Cahill and coauthors worked with MESSENGER-derived and rock-analog compositions to constrain petrologic models of the lavas that erupted on the surface of Mercury. Rock analogs included a partial melt of the Indarch meteorite and a range of Mg-rich terrestrial rocks. Their work shows the lavas on Mercury are most similar to terrestrial magnesian basalt (with lowered FeO content). The implications of the modeling are that Mg-rich lavas came from high-temperature sources in Mercury's mantle and erupted at high temperature with exceptionally low viscosity into thinly bedded and laterally extensive flows, concepts open to further evaluation by laboratory experiments and by geologic mapping of Mercury's surface using MESSENGER's imaging system and laser altimeter to document flow features and dimensions.

  20. Stratigraphic imaging of sub-basalt sediments using waveform tomography of wide-angle seismic data

    Science.gov (United States)

    Sain, K.; Gao, F.; Pratt, G.; Zelt, C. A.

    2003-12-01

    The oil industry is interested in imaging the fine structures of sedimentary formations masked below basalt flows for commercial exploration of hydrocarbons. Seismic exploration of sediments hidden below high-velocity basalt cover is a difficult problem because near-vertical reflection data are contaminated with multiples, converted waves and scattering noise generated by interbeds, breccia and vesicles within the basalt. The noise becomes less prominent as the source-receiver offset increases, and the signals carrying sub-surface information stand out at the wide-angle range. The tomography of first arrival traveltime data can provide little information about the underlying low-velocity sediments. Traveltime inversion of wide-angle seismic data including both first arrivals and identifiable wide-angle reflected phases has been an important tool in the delineation of the large-scale velocity structure of sub-basalt sediments, although it lacks the small-scale velocity details. Here we apply 2-D full-waveform inversion ("waveform tomography") to wide-angle seismic data with a view to extracting the small-scale stratigraphic features of sedimentary formations. Results from both synthetic data, generated for a realistic earth model, and field dataset from the basalt covered Saurashtra peninsula, India, will be presented. This approach has potential to delineate thin sedimentary layers hidden below thick basalt cover also, and may serve as a powerful tool to image sedimentary basins, where they are covered by high-velocity materials like basalts, salts, carbonates, etc. in various parts of the world.

  1. Subseafloor basalts as fungal habitats

    Directory of Open Access Journals (Sweden)

    M. Ivarsson

    2012-09-01

    Full Text Available The oceanic crust is believed to host the largest potential habitat for microbial life on Earth, yet, still we lack substantial information about the abundance, diversity, and consequence of its biosphere. The last two decades have involved major research accomplishments within this field and a change in view of the ocean crust and its potential to harbour life. Here fossilised fungal colonies in subseafloor basalts are reported from three different seamounts in the Pacific Ocean. The fungal colonies consist of various characteristic structures interpreted as fungal hyphae, fruit bodies and spores. The fungal hyphae are well preserved with morphological characteristics such as hyphal walls, septa, thallic conidiogenesis, and hyphal tips with hyphal vesicles within. The fruit bodies consist of large (∼50–200 µm in diameter body-like structures with a defined outer membrane and an interior filled with calcite. The fruit bodies have at some stage been emptied of their contents of spores and filled by carbonate-forming fluids. A few fruit bodies not filled by calcite and with spores still within support this interpretation. Spore-like structures (ranging from a few µm to ∼20 µm in diameter are also observed outside of the fruit bodies and in some cases concentrated to openings in the membrane of the fruit bodies. The hyphae, fruit bodies and spores are all closely associated with a crust lining the vein walls that probably represent a mineralized biofilm. The results support a fungal presence in deep subseafloor basalts and indicate that such habitats were vital between ∼81 and 48 Ma.

  2. Basalt-trachybasalt samples in Gale Crater, Mars

    International Nuclear Information System (INIS)

    Edwards, Peter H.; Anderson, Ryan B.; Dyar, Darby

    2017-01-01

    The ChemCam instrument on the Mars Science Laboratory (MSL) rover, Curiosity, observed numerous igneous float rocks and conglomerate clasts, reported previously. A new statistical analysis of single-laser-shot spectra of igneous targets observed by ChemCam shows a strong peak at ~55 wt% SiO 2 and 6 wt% total alkalis, with a minor secondary maximum at 47–51 wt% SiO 2 and lower alkali content. The centers of these distributions, together with the rock textures, indicate that many of the ChemCam igneous targets are trachybasalts, Mg# = 27 but with a secondary concentration of basaltic material, with a focus of compositions around Mg# = 54. We suggest that all of these igneous rocks resulted from low-pressure, olivine-dominated fractionation of Adirondack (MER) class-type basalt compositions. This magmatism has subalkaline, tholeiitic affinities. The similarity of the basalt endmember to much of the Gale sediment compositions in the first 1000 sols of the MSL mission suggests that this type of Fe-rich, relatively low-Mg#, olivine tholeiite is the dominant constituent of the Gale catchment that is the source material for the fine-grained sediments in Gale. The similarity to many Gusev igneous compositions suggests that it is a major constituent of ancient Martian magmas, and distinct from the shergottite parental melts thought to be associated with Tharsis and the Northern Lowlands. Finally, the Gale Crater catchment sampled a mixture of this tholeiitic basalt along with alkaline igneous material, together giving some analogies to terrestrial intraplate magmatic provinces.

  3. Solubility of platinum-arsenide melt and sperrylite in synthetic basalt at 0.1 MPa and 1200 °C with implications for arsenic speciation and platinum sequestration in mafic igneous systems

    Science.gov (United States)

    Canali, A. C.; Brenan, J. M.; Sullivan, N. A.

    2017-11-01

    To better understand the Pt-As association in natural magmas, experiments were done at 1200 °C and 0.1 MPa to measure the solubility of Pt and Pt-arsenide phases (melt and sperrylite, PtAs2), as well as to determine the oxidation state, and identify evidence for Pt-As complexing, in molten silicate. Samples consisting of synthetic basalt contained in chromite crucibles were subject to three experimental procedures. In the first, platinum solubility in the synthetic basalt was determined without added arsenic by equilibrating the sample with a platinum source (embedded wire or bead) in a gas-mixing furnace. In the second, the sample plus a Pt-arsenide source was equilibrated in a vacuum-sealed fused quartz tube containing a solid-oxide oxygen buffer. The third approach involved two steps: first equilibrating the sample in a gas-mixing furnace, then with added arsenide melt in a sealed quartz tube. Oxygen fugacity was estimated in the latter step using chromite/melt partitioning of vanadium. Method two experiments done at high initial arsenic activity (PtAs melt + PtAs2), showed significant loss of arsenic from the sample, the result of vapour transfer to newly-formed arsenide phases in the buffer. Method three experiments showed no loss of arsenic, yielding a uniform final distribution in the sample. Analyses of run-product glasses from experiments which did not show arsenic loss reveal significant increase in arsenic concentrations with fO2, varying from ∼10 ppm (FMQ-3.25) to >10,000 ppm (FMQ + 5.5). Despite very high arsenic loadings (>1000 ppm), the solubility of Pt is similar in arsenic-bearing and arsenic-free glasses. The variation in arsenic solubility with fO2 shows a linear relationship, that when corrected for the change in the activity of dissolved arsenic with the melt ferric/ferrous ratio, yields a solubility-fO2 relationship consistent with As3+ as the dissolved species. This result is confirmed by X-ray absorption near edge structure (XANES

  4. Some aspects of the minor element chemistry of lunar mare basalts

    International Nuclear Information System (INIS)

    Ringwood, A.E.

    1975-01-01

    The principal minor element (including Ti) characteristics of mare basalts which must be explained by an acceptable theory of petrogenesis are reviewed. Recent hypotheses have proposed that mare basalts formed by equilibrium partial melting of pyroxene-rich cumulates which underlay and were complementary to the anorthositic crust. These hypotheses are examined in detail and are rejected on several grounds. A new hypothesis based upon partial melting under conditions of surface or local equilibrium is proposed. It is assumed that the moon accreted from material which had ultimately formed by fractional condensation from a gas phase of appropriate composition. A disequilibrium mineral assemblage with a bulk composition similar to that of the pyroxenite source region of mare basalts as derived from experimental petrological considerations was formed. It is considered that this model is capable of explaining the principal minor element characteristics of mare basalts and is consistent with interpretations of the major element chemistry of their source region based upon experimental petrology. (Auth.)

  5. Giant Plagioclase Basalts, eruption rate versus time

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Earth System Science; Volume 111; Issue 4. Giant Plagioclase Basalts, eruption rate versus time: Response to Sheth's comments and some additional thoughts. Gautam Sen. Volume 111 Issue 4 December 2002 pp 487-488 ...

  6. Naming Lunar Mare Basalts: Quo Vadimus Redux

    Science.gov (United States)

    Ryder, G.

    1999-01-01

    Nearly a decade ago, I noted that the nomenclature of lunar mare basalts was inconsistent, complicated, and arcane. I suggested that this reflected both the limitations of our understanding of the basalts, and the piecemeal progression made in lunar science by the nature of the Apollo missions. Although the word "classification" is commonly attached to various schemes of mare basalt nomenclature, there is still no classification of mare basalts that has any fundamental grounding. We remain basically at a classification of the first kind in the terms of Shand; that is, things have names. Quoting John Stuart Mill, Shand discussed classification of the second kind: "The ends of scientific classification are best answered when the objects are formed into groups respecting which a greater number of propositions can be made, and those propositions more important than could be made respecting any other groups into which the same things could be distributed." Here I repeat some of the main contents of my discussion from a decade ago, and add a further discussion based on events of the last decade. A necessary first step of sample studies that aims to understand lunar mare basalt processes is to associate samples with one another as members of the same igneous event, such as a single eruption lava flow, or differentiation event. This has been fairly successful, and discrete suites have been identified at all mare sites, members that are eruptively related to each other but not to members of other suites. These eruptive members have been given site-specific labels, e.g., Luna24 VLT, Apollo 11 hi-K, A12 olivine basalts, and Apollo 15 Green Glass C. This is classification of the first kind, but is not a useful classification of any other kind. At a minimum, a classification is inclusive (all objects have a place) and exclusive (all objects have only one place). The answer to "How should rocks be classified?" is far from trivial, for it demands a fundamental choice about nature

  7. From shifting silt to solid stone: the manufacture of synthetic basalt in ancient mesopotamia

    Science.gov (United States)

    Stone; Lindsley; Pigott; Harbottle; Ford

    1998-06-26

    Slabs and fragments of gray-black vesicular "rock," superficially resembling natural basalt but distinctive in chemistry and mineralogy, were excavated at the second-millennium B.C. Mesopotamian city of Mashkan-shapir, about 80 kilometers south of Baghdad, Iraq. Most of this material appears to have been deliberately manufactured by the melting and slow cooling of local alluvial silts. The high temperatures (about 1200 degreesC) required and the large volume of material processed indicate an industry in which lithic materials were manufactured ("synthetic basalt") for grinding grain and construction.

  8. The socio-materiality of learning practices and implications for the field of learning technology

    Directory of Open Access Journals (Sweden)

    Aditya Johri

    2011-12-01

    Full Text Available Although the use of digital information technologies in education has becomecommonplace, there are few, if any, central guiding frameworks or theories thatexplicate the relationship between technology and learning practices. In thispaper, I argue that such a theoretical framework can assist scholars and practitionersalike by working as a conduit to study and design learning technologies.Towards this goal, I propose socio-materiality as a key theoretical construct withvaluable insights and implications for the field of learning technology. Sociomaterialityhelps balance the disproportionate attention given to either the socialimplications of technology use or the material aspects of technology design.Furthermore, I forward ‘socio-material bricolage' as a useful analytical frameworkto examine and design technology-infused learning environments. I illustratethe value of the framework by applying it to three case studies of formaland informal technology-based learning.

  9. Characterization of iron-enriched synthetic basalt for transuranic containment

    International Nuclear Information System (INIS)

    Flinn, J.E.; Henslee, S.P.; Kelsey, P.V.; Tallman, R.L.; Welch, J.M.

    1980-01-01

    In the slagging pyrolytic incineration process, combustibles are burned and noncombustibles, including metals, are oxidized into a molten , an electromelter, where the molten slag, with further processing conducted in a heated tundish, e.g. is allowed to homogenize (within a reasonable time period) and then cast into large, cylindrical metal containers. Analyses of Idaho National Engineering Laboratory waste slags show them similar in composition and appearance to natural basalts, but rich in iron. The electromelt process and the resulting iron-rich castings offer great promise for rendering nuclear waste into a stable form. The process offers great flexibility with regard to both compositional variation of the incoming waste and the high rates at which the waste can be introduced and cast. The cast product, a fine-grained basalt-like material, shows excellent homogeneity with little or no reaction to the steel containment. The preliminary mechanical and chemical durability data show the form to have adequate containment properties for TRU waste. However, work presently underway to improve these properties through additives and controlled cooling cycles has greatly enhanced the durability of the waste form. Furthermore, recent evidence indicates that divalent iron (Fe 2+ ) included in the crystalline phases of granites and basalts imparts a resistance to leaching of uranium and other actinide ions

  10. Dissolution of basaltic glass in seawater: Mechanism and rate

    International Nuclear Information System (INIS)

    Crovisier, J.L.; Honnorez, J.; Eberhart, J.P.

    1987-01-01

    Basaltic glasses are considered as natural analogues for nuclear waste glasses. Thermodynamic computer codes used to evaluate long term behavior of both nuclear waste and basaltic glasses require the knowledge of the dissolution mechanism of the glass network. The paper presents the results of a series of experiments designed to study the structure and chemical composition of alteration layers formed on the surface of artificial tholeiitic glass altered in artificial seawater. Experiments were performed at 60 degree C, 1 bar and 350 bars in non-renewed conditions. A natural sample from Palagonia (Sicily) has been studied by electron microscopy and comparison between natural and experimental palagonitic layers is made. The behavior of dissolved silica during experiments, and both the structure and the chemical composition of the palagonitic layers, indicate that they form by precipitation of secondary minerals from solution after a total breakdown of the glassy network, i.e., congruent dissolution of the glass. Hence the dissolution equation necessary for thermodynamic modelling of basaltic glass dissolution in seawater at low temperature must be written as a simple stoichiometric process. These experiments indicate that the transformation of glass to palagonitic material is not isovolumetric. Hence it is preferable to use Fe or Ti as conservative elements for chemical budget calculations

  11. Basalt Pb isotope analysis and the prehistoric settlement of Polynesia.

    Science.gov (United States)

    Weisler, M I; Woodhead, J D

    1995-01-01

    The prehistoric settlement of the Pacific Ocean has intrigued scholars and stimulated anthropological debate for the past two centuries. Colonized over a few millennia during the mid to late Holocene, the islands of the Pacific--displaying a wide diversity of geological and biotic variability--provided the stage for endless "natural experiments" in human adaptation. Crucial to understanding the evolution and transformation of island societies is documenting the relative degree of interisland contacts after island colonization. In the western Pacific, ideal materials for archaeologically documenting interisland contact--obsidian, pottery, and shell ornaments--are absent or of limited geographic distribution in Polynesia. Consequently, archaeologists have relied increasingly on fine-grained basalt artifacts as a means for documenting colonization routes and subsequent interisland contacts. Routinely used x-ray fluorescence characterization of oceanic island basalt has some problems for discriminating source rocks and artifacts in provenance studies. The variation in trace and major element abundances is largely controlled by near-surface magma-chamber processes and is broadly similar between most oceanic islands. We demonstrate that Pb isotope analysis accurately discriminates rock source and is an excellent technique for charting the scale, frequency, and temporal span of imported fine-grained basalt artifacts found throughout Polynesia. The technique adds another tool for addressing evolutionary models of interaction, isolation, and cultural divergence in the eastern Pacific. PMID:7892194

  12. Vapor segregation and loss in basaltic melts

    Science.gov (United States)

    Edmonds, M.; Gerlach, T.M.

    2007-01-01

    Measurements of volcanic gases at Pu'u'O??'o??, Kilauea Volcano, Hawai'i, reveal distinct degassing regimes with respect to vapor segregation and loss during effusive activity in 2004-2005. Three styles of vapor loss are distinguished by the chemical character of the emitted volcanic gases, measured by open path Fourier transform infrared spectroscopy: 1 persistent continuous gas emission, 2 gas piston events, and 3 lava spattering. Persistent continuous gas emission is associated with magma ascent and degassing beneath the crater vents, then eruption of the degassed magma from flank vents. Gas piston events are the result of static gas accumulation at depths of 400-900 m beneath Pu'u'O??'o??. A CO2-rich gas slug travels up the conduit at a few meters per second, displacing magma as it expands. Lava spattering occurs due to dynamic bubble coalescence in a column of relatively stagnant magma. The Large gas bubbles are H2O rich and are generated by open-system degassing at depths of gas accumulation and dynamic bubble coalescence are both manifestations of vapor segregation in basaltic melts, but their implications differ. Accumulation and segregation of CO2-rich vapor at depth does not deplete the melt of H2O (required to drive lava fountains near to the surface) and therefore gas piston events can occur interspersed with lava fountaining activity. Lava spattering, however, efficiently strips H2O-rich vapor from magma beneath the crater vents; the magma must then erupt effusively from vents on the flank of the cone. ?? 2007 The Geological Society of America.

  13. Constraints on ocean ridge basalt generation from Gakkel Ridge basalts

    Science.gov (United States)

    Langmuir, C. H.; Michael, P.; Standish, J.; Goldstein, S.

    2006-12-01

    The Gakkel Ridge that traverses the Arctic Ocean from Greenland to Siberia provides five "natural experiments" with respect to our understanding of melt generation and delivery at ocean ridges. (1) It is the deepest of the ocean ridges, and tests the global correlations of basalt chemistry with axial depth and the origin of such correlations. (2) It is the slowest spreading ridge, and tests the influence of ultra-slow spreading on magma generation without the complexity of oblique spreading or multiple transform offsets. (3) The samples are both on- and off-axis, allowing tests of the similarity of on- and off-axis volcanism. (4) It provides a test of the veined mantle disequilibrium melting hypothesis for MORB, since both ultra-slow spreading rate and great depth suggest minimum extents of melting, with the extent of melting decreasing progressively towards the east. (5) It tests segmentation models, because there are no transform offsets along the ridge, and the slow spreading rates should lead to maximum melt focusing along strike. The comprehensive major element, trace element and isotopic data set for the rocks obtained on the AMORE cruise allows investigation of all of these issues. (1) The Gakkel fits global depth-chemistry correlations, and major and trace element data as well as crustal thickness suggest small extents of melting in this region, decreasing towards the east. (2)Ultra-slow spreading leads to a thicker lithospheric lid and more garnet influence towards the east. The effects of thick lithosphere and mantle temperature on melting can be clearly distinguished in this region, and contrast with global systematics. This suggests that lithosphere variations are of minor importance in controlling the global array. (3) Off-axis samples are more diverse than on-axis samples, confirming the importance of off-axis volcanism at ultra-slow ridges. (4) Trace element data do not show an increase in a "veined component" towards the east as spreading rate

  14. Constraining the H2O and CO2 Contents of Basaltic Arc Magmas from Melt Inclusions: Diffusive H Loss and Shrinkage Bubble Formation, and Implications for the CO2 Contents of Primary Melts

    Science.gov (United States)

    Wallace, P. J.; Walowski, K. J.; Aster, E. M.

    2016-12-01

    The volatiles H2O and CO2 play a major role in arc magmatism, and tracking their return flux from the subducted slab to the Earth's surface is important for understanding global geochemical cycles. Melt inclusions (MIs) are a commonly used tool for measuring the concentrations of volatiles in magmas. However, recent studies have shown that MIs are imperfect storage containers that can lose H by diffusion through the mineral host and CO2 due to formation of a vapor bubble in the inclusion. Here, we use data for MIs from primitive basaltic magmas in the Lassen region of the Cascade arc [1] to show how post-entrapment processes can be distinguished from magmatic variability. Using the highest measured H2O from MIs at each volcanic center, we use correlations of volatile and trace element ratios (H2O/Ce, Cl/Nb, Sr/Nd) to demonstrate that primary geochemical variability results from variable addition of a hydrous subduction component to the mantle wedge. However, volcanic centers in the Lassen region and at nearby Mt. Shasta with the highest Sr/Nd, and therefore largest amount of a subduction component, have low H2O/Ce, suggesting that MIs in the most H2O-rich magmas were affected by diffusive H loss after trapping. For CO2 in MIs, we correct for the loss of CO2 to a vapor bubble formed by post-entrapment crystallization and thermal contraction [2]. The results suggest minimum magmatic values of 1500-6000 ppm CO2, but these likely reflect the depths of stalling and crystallization in the crust rather than primary magma values. Our results are similar to estimates for other arc volcanoes that range up to 4000 ppm CO2 (Fuego [3]), 3800 ppm (Klyuchevskoy [4]) and 7000 ppm (Jorullo [2]). The highest of these values overlap with the estimate of 0.6 - 1.3 wt% CO2 in primary arc magmas inferred from arc volcano CO2 emissions [5]. [1] Walowski et al. 2016, EPSL; [2] Aster et al. 2016, JVGR; [3] Moore et al. 2015, Am. Min.; [4] Mironov et al. 2015, EPSL; [5] Wallace 2005, JVGR.

  15. South Pole-Aitken Sample Return Mission: Collecting Mare Basalts from the Far Side of the Moon

    Science.gov (United States)

    Gillis, J. J.; Jolliff, B. L.; Lucey, P. G.

    2003-01-01

    We consider the probability that a sample mission to a site within the South Pole-Aitken Basin (SPA) would return basaltic material. A sample mission to the SPA would be the first opportunity to sample basalts from the far side of the Moon. The near side basalts are more abundant in terms of volume and area than their far-side counterparts (16:1), and the basalt deposits within SPA represent approx. 28% of the total basalt surface area on the far side. Sampling far-side basalts is of particular importance because as partial melts of the mantle, they could have derived from a mantle that is mineralogically and chemically different than determined for the nearside, as would be expected if the magma ocean solidified earlier on the far side. For example, evidence to support the existence of high-Th basalts like those that appear to be common on the nearside in the Procellarum KREEP Terrane has been found. Although SPA is the deepest basin on the Moon, it is not extensively filled with mare basalt, as might be expected if similar amounts of partial melting occurred in the mantle below SPA as for basins on the near side. These observations may mean that mantle beneath the far-side crust is lower in Th and other heat producing elements than the nearside. One proposed location for a sample-return landing site is 60 S, 160 W. This site was suggested to maximize the science return with respect to sampling crustal material and SPA impact melt, however, basaltic samples would undoubtedly occur there. On the basis of Apollo samples, we should expect that basaltic materials would be found in the vicinity of any landing site within SPA, even if located away from mare deposits. For example, the Apollo 16 mission landed in an ancient highlands region 250-300 km away from the nearest mare-highlands boundary yet it still contains a small component of basaltic samples (20 lithic fragments ranging is size from <1 to .01 cm). A soil sample from the floor of SPA will likely contain an

  16. Lu-Hf constraints on the evolution of lunar basalts

    International Nuclear Information System (INIS)

    Fujimaki, H.; Tatsumoto, M.

    1984-01-01

    Very low Ti basalts andd green glass samples from the moon show high Lu/Hf ratios and low Hf concentrations. Low-Ti lunar basalts show high and variable Lu/Hf ratios and higher Hf concentrations, whereas high-Ti lunar basalts show low Lu/Hf ratios and high Hf concentrations. KREEP basalts have constant Lu/Hf ratios and high but variable Hf concentrations. Using the Lu-Hf behavior as a constraint, we propose a model for the mare basalts evolution. This constraint requires extensive crystallization of the primary lunar magma ocean prior to formation of the lunar mare basalt sources and the KREEP basalts. Mare basalts are produced by the melting of the cumulate rocks, and KREEP basalts represent the residual liquid of the magma ocean

  17. Can we identify source lithology of basalt?

    Science.gov (United States)

    Yang, Zong-Feng; Zhou, Jun-Hong

    2013-01-01

    The nature of source rocks of basaltic magmas plays a fundamental role in understanding the composition, structure and evolution of the solid earth. However, identification of source lithology of basalts remains uncertainty. Using a parameterization of multi-decadal melting experiments on a variety of peridotite and pyroxenite, we show here that a parameter called FC3MS value (FeO/CaO-3*MgO/SiO2, all in wt%) can identify most pyroxenite-derived basalts. The continental oceanic island basalt-like volcanic rocks (MgO>7.5%) (C-OIB) in eastern China and Mongolia are too high in the FC3MS value to be derived from peridotite source. The majority of the C-OIB in phase diagrams are equilibrium with garnet and clinopyroxene, indicating that garnet pyroxenite is the dominant source lithology. Our results demonstrate that many reputed evolved low magnesian C-OIBs in fact represent primary pyroxenite melts, suggesting that many previous geological and petrological interpretations of basalts based on the single peridotite model need to be reconsidered.

  18. Environmental issue identification for the Basalt Waste Isolation Project

    International Nuclear Information System (INIS)

    Carrell, D.J.; Jones, K.A.

    1980-04-01

    A preliminary evaluation of environmental issues is provided in this report. It contains summary of the thought process that was used during the area characterization studies for a geological repository for high-level radioactive wastes. Environmental issues are discussed separately for construction, operation, and long term isolation aspects of a repository in basalt. During construction the primary environmental concerns are public perception and water resources; intermediate concerns are air quality, ecosystems, physical resources, and cultural and social resources. During operation, the primary environmental issues concern the transport of radioactive materials and physical resources. Long term environmental issues envolve water resources and borehole plugging

  19. Primitive off-rift basalts from Iceland and Jan Mayen

    DEFF Research Database (Denmark)

    Debaille, Vinciane; Trønnes, Reidar G.; Brandon, Alan D.

    2009-01-01

    and appear to be contaminated at a shallow level. The 187Os/188Os ratios in the remaining lavas with >30 ppt Os (n = 17) range between 0.12117 and 0.13324. These values are surprisingly low for oceanic island basalts and include some samples that are less than putative present-day primitive upper mantle (PUM....... Material from the Iceland mantle plume likely migrates at depth until it reaches the tensional setting of the Jan Mayen Fracture Zone, where it undergoes low-degree partial melting. At a first-order, isotopic co-variations can be interpreted as broadly binary mixing curves between two primary end...

  20. Chopped basalt fibres: A new perspective in reinforcing poly(lactic acid to produce injection moulded engineering composites from renewable and natural resources

    Directory of Open Access Journals (Sweden)

    P. Tamas

    2013-02-01

    Full Text Available This paper focuses on the reinforcing of Poly(lactic acid with chopped basalt fibres by using silane treated and untreated basalt fibres. Composite materials with 5–10–15–20–30–40 wt% basalt fibre contents were prepared from silane sized basalt fibres using extrusion, and injection moulding, while composites with 5–10–15 wt% basalt fibre contents were also prepared by using untreated basalt fibres as control. The properties of the injection moulded composites were extensively examined by using quasi-static (tensile, three-point bending and dynamic mechanical tests (notched and unnotched Charpy impact tests, dynamic mechanical analysis (DMA, differential scanning calorimetry (DSC, heat deflection temperature (HDT analysis, dimensional stability test, as well as melt flow index (MFI analysis and scanning electron microscopic (SEM observations. It was found that silane treated chopped basalt fibres are much more effective in reinforcing Poly(lactic acid than natural fibres; although basalt fibres are not biodegradable but they are still considered as natural (can be found in nature in the form of volcanic rocks and biologically inert. It is demonstrated in this paper that by using basalt fibre reinforcement, a renewable and natural resource based composite can be produced by injection moulding with excellent mechanical properties suitable even for engineering applications. Finally it was shown that by using adequate drying of the materials, composites with higher mechanical properties can be achieved compared to literature data.

  1. Zircon evidence for incorporation of terrigenous sediments into the magma source of continental basalts.

    Science.gov (United States)

    Xu, Zheng; Zheng, Yong-Fei; Zhao, Zi-Fu

    2018-01-09

    Crustal components may be incorporated into continental basalts by either shallow contamination or deep mixing. While the former proceeds at crustal depths with common preservation of refractory minerals, the latter occurs at mantle depths with rare survival of relict minerals. Discrimination between the two mechanisms has great bearing to subcontinental mantle geochemistry. Here we report the occurrence of relict zircons in Cenozoic continental basalts from eastern China. A combined study of zircon U-Pb ages and geochemistry indicates that detrital zircons were carried by terrigenous sediments into a subcontinental subduction zone, where the zircon were transferred by fluids into the magma sources of continental basalts. The basalts were sampled from three petrotectonic units with distinct differences in their magmatic and metamorphic ages, making the crustal contamination discernible. The terrigenous sediments were carried by the subducting oceanic crust into the asthenospheric mantle, producing both soluble and insoluble materials at the slab-mantle interface. These materials were served as metasomatic agents to react with the overlying mantle wedge peridotite, generating a kind of ultramafic metasomatites that contain the relict zircons. Therefore, the occurrence of relict zircons in continental basalts indicates that this refractory mineral can survive extreme temperature-pressure conditions in the asthenospheric mantle.

  2. Performance of basaltic dust issued from an asphaltic plant as a flocculant additive for wastewater treatment.

    Science.gov (United States)

    Ramírez Zamora, R M; Chávez Mejia, A; Domínguez Mora, R; Durán Moreno, A

    2004-01-01

    The feasibility of using basaltic dust as a flocculant additive or coagulant aid for wastewater treatment was assessed in this research. The experimental study was divided into two stages: 1) physicochemical characterisation of the basaltic dust by applying standardised techniques, and 2) evaluation of this material as flocculant additive for the coagulation-flocculation of wastewater treated for reuse. Coagulation-flocculation experiments were carried out in the laboratory with a mixture of industrial and municipal wastewater samples collected from two points of the final discharge of the Mexico City sewerage system. Aluminium sulphate and lime were used as coagulants and the basaltic dust as flocculant additive, by applying the jar-test technique. The results of the corrosivity, reactivity, explosiveness, toxicity, inflammability and biological risk tests indicated that this material is classified as a non-hazardous waste (according to the Mexican legislation, NOM-052-ECOL-1993). The density, oxide content and particle size values of basaltic dust were similar to those reported for the flocculant additive denominated activated silica. The jar test results showed a positive effect of basaltic dust over the effluent and sludge qualities, to the extent that coagulant doses can be reduced 30% (from 150 mg/L to 110 mg/L of Al2(SO4)3).

  3. Vapor deposition in basaltic stalactites, Kilauea, Hawaii

    Science.gov (United States)

    Baird, A. K.; Mohrig, D. C.; Welday, E. E.

    Basaltic stalacties suspended from the ceiling of a large lava tube at Kilauea, Hawaii, have totally enclosed vesicles whose walls are covered with euhedral FeTi oxide and silicate crystals. The walls of the vesicles and the exterior surfaces of stalactites are Fe and Ti enriched and Si depleted compared to common basalt. Minerals in vesicles have surface ornamentations on crystal faces which include alkali-enriched, aluminosilicate glass(?) hemispheres. No sulfide-, chloride-, fluoride-, phosphate- or carbonate-bearing minerals are present. Minerals in the stalactites must have formed by deposition from an iron oxide-rich vapor phase produced by the partial melting and vaporization of wall rocks in the tube.

  4. Hardness of basaltic glass-ceramics

    DEFF Research Database (Denmark)

    Jensen, Martin; Smedskjær, Morten Mattrup; Estrup, Maja

    2009-01-01

    The dependence of the hardness of basaltic glass-ceramics on their degree of crystallisation has been explored by means of differential scanning calorimetry, optical microscopy, x-ray diffraction, and Vickers indentation. Different degrees of crystallisation in the basaltic glasses were achieved...... by varying the temperature of heat treatment. The predominant crystalline phase in the glass was identified as augite. It was found that the hardness of the glass phase decreased slightly with an increase in the degree of crystallisation, while that of the augite phase drastically decreased....

  5. The genesis and evolution of Hannuoba Basalt based on the Xiaomaping basalt profile

    Science.gov (United States)

    Huixin, Hei; Shangguo, Su; Yu, Wang

    2014-05-01

    Hannuoba basalt lies in the northern of North China. It erupted in Cenozoic with well outcrops and widespread ultramafic xenoliths. This study focuses on the Xiaomaping basalt profile in Hannuoba district. The profile can be distinguished for 7 layers with each bottom of the layer enriched with ultramafic xenoliths. In the Hark polt, all major elements have good correlation with the MgO content, showing the basalt from different layers having an consistent evolution. The phenocrysts in the basalt from different layers are rare and mostly within 5% with main faces as Ol, Cpx and Opx. The chemical characteristic of the basalt shows mutative features, Mg# (52.0-67.7), CaO (7.3-8.5wt. %), Ni (82-192ppm) and Cr (65-192ppm). The basalts have apparent LREE enrichment and are rich in HFSE (Nb,Ta,Zr) and in LILE (Ba, Sr). All the basalt layers do not show manifest negative Eu with δEu=1.01-1.05. The ultramafic xenoliths are spinel-lherzolite, with weak lack of LREE. Trace element ratios, Ba / Rb and Rb / Sr, show that the source might have experienced some extent of fluid metasomatism. According to the La and La/Sm plot, the basalts are mainly controlled by the partial melting, and the great extent of fractional crystallization did not happened during the evolution process. Based on current published experimental results and theoretical petrology analysis, Hannuoba basalts formed in equilibrium with pyroxenite with clinopyroxene and garnet as the main mineral faces in the source and accounting olivine in small extent.

  6. Geochemical constraints on the spatial distribution of recycled oceanic crust in the mantle source of late Cenozoic basalts, Vietnam

    Science.gov (United States)

    Hoang, Thi Hong Anh; Choi, Sung Hi; Yu, Yongjae; Pham, Trung Hieu; Nguyen, Kim Hoang; Ryu, Jong-Sik

    2018-01-01

    This study presents a comprehensive analysis of the major and trace element, mineral, and Sr, Nd, Pb and Mg isotopic compositions of late Cenozoic intraplate basaltic rocks from central and southern Vietnam. The Sr, Nd, and Pb isotopic compositions of these basalts define a tight linear array between Indian mid-ocean-ridge basalt (MORB)-like mantle and enriched mantle type 2 (EM2) components. These basaltic rocks contain low concentrations of CaO (6.4-9.7 wt%) and have high Fe/Mn ratios (> 60) and FeO/CaO-3MgO/SiO2 values (> 0.54), similar to partial melts derived from pyroxenite/eclogite sources. This similarity is also supported by the composition of olivine within these samples, which contains low concentration of Ca and high concentrations of Ni, and shows high Fe/Mn ratios. The basaltic rocks have elevated Dy/Yb ratios that fall within the range of melts derived from garnet lherzolite material, although their Yb contents are much higher than those of modeled melts derived from only garnet lherzolite material and instead plot near the modeled composition of eclogite-derived melts. The Vietnamese basaltic rocks have lighter δ26Mg values (- 0.38 ± 0.06‰) than is expected for the normal mantle (- 0.25 ± 0.07‰), and these values decrease with decreasing Hf/Hf* and Ti/Ti* ratios, indicating that these basalts were derived from a source containing carbonate material. On primitive mantle-normalized multi-element variation diagrams, the central Vietnamese basalts are characterized by positive Sr, Eu, and Ba anomalies. These basalts also plot within the pelagic sediment field in Pbsbnd Pb isotopic space. This suggests that the mantle source of the basalts contained both garnet peridotite and recycled oceanic crust. A systematic analysis of variations in geochemical composition in basalts from southern to central Vietnam indicates that the recycled oceanic crust (possibly the paleo-Pacific slab) source material contains varying proportions of gabbro, basalt, and

  7. ``Phantom'' Modes in Ab Initio Tunneling Calculations: Implications for Theoretical Materials Optimization, Tunneling, and Transport

    Science.gov (United States)

    Barabash, Sergey V.; Pramanik, Dipankar

    2015-03-01

    Development of low-leakage dielectrics for semiconductor industry, together with many other areas of academic and industrial research, increasingly rely upon ab initio tunneling and transport calculations. Complex band structure (CBS) is a powerful formalism to establish the nature of tunneling modes, providing both a deeper understanding and a guided optimization of materials, with practical applications ranging from screening candidate dielectrics for lowest ``ultimate leakage'' to identifying charge-neutrality levels and Fermi level pinning. We demonstrate that CBS is prone to a particular type of spurious ``phantom'' solution, previously deemed true but irrelevant because of a very fast decay. We demonstrate that (i) in complex materials, phantom modes may exhibit very slow decay (appearing as leading tunneling terms implying qualitative and huge quantitative errors), (ii) the phantom modes are spurious, (iii) unlike the pseudopotential ``ghost'' states, phantoms are an apparently unavoidable artifact of large numerical basis sets, (iv) a presumed increase in computational accuracy increases the number of phantoms, effectively corrupting the CBS results despite the higher accuracy achieved in resolving the true CBS modes and the real band structure, and (v) the phantom modes cannot be easily separated from the true CBS modes. We discuss implications for direct transport calculations. The strategy for dealing with the phantom states is discussed in the context of optimizing high-quality high- κ dielectric materials for decreased tunneling leakage.

  8. Radiation shielding properties of high performance concrete reinforced with basalt fibers infused with natural and enriched boron

    Energy Technology Data Exchange (ETDEWEB)

    Zorla, Eyüp; Ipbüker, Cagatay [University of Tartu, Institute of Physics (Estonia); Biland, Alex [US Basalt Corp., Houston (United States); Kiisk, Madis [University of Tartu, Institute of Physics (Estonia); Kovaljov, Sergei [OÜ Basaltest, Tartu (Estonia); Tkaczyk, Alan H. [University of Tartu, Institute of Physics (Estonia); Gulik, Volodymyr, E-mail: volodymyr.gulik@gmail.com [Institute for Safety Problems of Nuclear Power Plants, Lysogirska 12, of. 201, 03028 Kyiv (Ukraine)

    2017-03-15

    Highlights: • Basalt fiber infused with natural and enriched boron in varying proportions. • Gamma-ray attenuation remains stable with addition of basalt-boron fiber. • Improvement in neutron shielding for nuclear facilities producing fast fission spectrum. • Basalt-boron fiber could decrease the shielding thickness in thermal spectrum reactors. - Abstract: The importance of radiation shielding is increasing in parallel with the expansion of the application areas of nuclear technologies. This study investigates the radiation shielding properties of two types of high strength concrete reinforced with basalt fibers infused with 12–20% boron oxide, containing varying fractions of natural and enriched boron. The gamma-ray shielding characteristics are analyzed with the help of the WinXCom, whereas the neutron shielding characteristics are modeled and computed by Monte Carlo Serpent code. For gamma-ray shielding, the attenuation coefficients of the studied samples do not display any significant variation due to the addition of basalt-boron fibers at any mixing proportion. For neutron shielding, the addition of basalt-boron fiber has negligible effects in the case of very fast neutrons (14 MeV), but it could considerably improve the neutron shielding of concrete for nuclear facilities producing a fast fission spectrum (e.g. with reactors as BN-800, FBTR) and thermal neutron spectrum (Light Water Reactors (LWR)). It was also found that basalt-boron fiber could decrease the thickness of radiation shielding material in thermal spectrum reactors.

  9. Strontium isotopes as tracers to delineate aquifer interactions and the influence of rainfall in the basalt plains of southeastern Australia

    Science.gov (United States)

    Raiber, Matthias; Webb, John A.; Bennetts, Darren A.

    2009-04-01

    SummaryTo better understand the spatial distribution of groundwater salinisation in western Victoria, southeast Australia, the interactions between a surficial basalt aquifer and an underlying extensive palaeodrainage ('deep lead') system were studied using a multi-disciplinary approach, combining strontium isotope analyses with major ion chemistry and the interpretation of geological and hydrogeological data. The strontium isotopes proved particularly useful in delineating flow paths and hydraulic connections between the two aquifers, which have contrasting 87Sr/ 86Sr ratios. The freshest basalt groundwaters lie beneath volcanoes and have 87Sr/ 86Sr signatures close to the whole-rock strontium isotope ratios of the basalts (˜0.7045), indicating the strong influence of basalt weathering. With increasing distance from the eruption points, basalt groundwaters become progressively more saline and the strontium isotope ratios evolve towards the more radiogenic signatures of local rainfall (0.710-0.711), due to the slow addition of infiltration concentrated by evapotranspiration during its passage through the thick, clay-rich soils developed on the basalt lavas. Overall, the influence of rainwater on the strontium isotope signatures of the basalt groundwater is much greater than that of basaltic weathering, indicating that rainwater can play a greater role in determining groundwater strontium composition than is often realised. Most parts of the palaeodrainage system beneath the basalt are preferentially recharged through the volcanoes, as shown by strong downwards hydraulic gradients and groundwater 87Sr/ 86Sr ratios similar to the least radiogenic basalt groundwaters. However, in the northwestern part, groundwater 87Sr/ 86Sr ratios are closer to those of the source material of the sediments (Palaeozoic bedrock), indicating that here recharge occurs predominantly in the headwaters where the basalts are absent. In the southern and western sections of the palaeodrainage

  10. Petrography of basalts from the Carlsberg ridge

    Digital Repository Service at National Institute of Oceanography (India)

    Banerjee, R.; Iyer, S.D.

    Petrographic characteristics of basalts collected from a segment of the Carlsberg Ridge (lat. 3 degrees 35'N to 3 degrees 41'N; long. 64 degrees 05'E to 64 degrees 09'E) show typical pillow lava zonations with variable concentrations of plagioclase...

  11. Hydrogen isotope systematics of submarine basalts

    Energy Technology Data Exchange (ETDEWEB)

    Kyser, T.K. (Saskatchewan Univ., Saskatoon (Canada). Dept. of Geological Sciences); O' Neil, J.R. (Geological Survey, Menlo Park, CA (USA))

    1984-10-01

    The D/H ratios and water contents in fresh submarine basalts from the Mid-Atlantic Ridge, the East Pacific Rise, and Hawaii indicate that the primary D/H ratios of many submarine lavas have been altered by processes including (1) outgassing, (2) addition of seawater at magmatic temperature, and (3) low-temperature hydration of glass. Decreases in deltaD and H/sub 2/O/sup +/ from exteriors to interiors of pillows are explained by outgassing of water whereas inverse relations between deltaD and H/sub 2/O/sup +/ in basalts from the Galapagos Rise and the FAMOUS Area are attributed to outgassing of CH/sub 4/ and H/sub 2/. A good correlation between deltaD values and H/sub 2/O is observed in a suite of submarine tholeiites dredged from the Kilauea East Rift Zone where seawater (added directly to the magma), affected only the isotopic compositions of hydrogen and argon. Analyses of some glassy rims indicate that the outer millimeter of the glass can undergo low-temperature hydration by hydroxyl groups having deltaD values as low as -100. deltaD values vary with H/sub 2/O contents of subaerial transitional basalts from Molokai, Hawaii, and subaerial alkali basalts from the Society Islands, indicating that the primary deltaD values were similar to those of submarine lavas. The results are discussed.

  12. Thermal models for basaltic volcanism on Io

    Science.gov (United States)

    Keszthelyil, L.; McEwen, A.

    1997-01-01

    We present a new model for the thermal emissions from active basaltic eruptions on Io. While our methodology shares many similarities with previous work, it is significantly different in that (1) it uses a field tested cooling model and (2) the model is more applicable to pahoehoe flows and lava lakes than fountain-fed, channelized, 'a'a flows. This model demonstrates the large effect lava porosity has on the surface cooling rate (with denser flows cooling more slowly) and provides a preliminary tool for examining some of the hot spots on Io. The model infrared signature of a basaltic eruption is largely controlled by a single parameter, ??, the average survival time for a lava surface. During an active eruption surfaces are quickly covered or otherwise destroyed and typical values of ?? for a basaltic eruption are expected to be on the order of 10 seconds to 10 minutes. Our model suggests that the Galileo SSI eclipse data are consistent with moderately active to quiescent basaltic lava lakes but are not diagnostic of such activity. Copyright 1997 by the American Geophysical Union.

  13. Equilibration of Leachants with Basalt Rock for Repository Simulation Tests

    Energy Technology Data Exchange (ETDEWEB)

    Jantzen, C.M.

    2001-07-02

    In a nuclear waste repository in basalt, the groundwater will have a low redox potential (Eh) which may affect the leach rate of SRP waste glass. Accurate laboratory simulations of conditions in a basalt reposition must maintain low Eh values throughout the course of the experiment. In this report, important parameters affecting the ability of basalt to maintain appropriate Eh-pH conditions are examined, in particular basalt type and groundwater simulation.

  14. Increased corrosion resistance of basalt reinforced cement compositions with nanosilica

    Directory of Open Access Journals (Sweden)

    URKHANOVA Larisa Alekseevna

    2014-08-01

    Full Text Available Disperse fiber reinforcement is used to improve deformation and shrinkage characteristics, flexural strength of concrete. Basalt roving and thin staple fiber are often used as mineral fibers. The paper considers the problems of using thin basalt fiber produced by centrifugal-blow method. Evaluation of the corrosion resistance of basalt fiber as part of the cement matrix was performed. Nanodispersed silica produced by electron beam accelerator was used to increase corrosion resistance of basalt fiber.

  15. Research strategies for safety evaluation of nanomaterials, Part I: evaluating the human health implications of exposure to nanoscale materials.

    Science.gov (United States)

    Thomas, Karluss; Sayre, Philip

    2005-10-01

    Nanotechnology has the potential to dramatically improve the effectiveness of a number of existing consumer and industrial products and could have a substantial impact on the development of new products ranging from disease diagnosis and treatment to environmental remediation. The broad range of possible nanotechnology applications could lead to substantive changes in industrial productivity, economic growth, and international trade. A continuing evaluation of the human health implications of exposure to nanoscale materials will be essential before the commercial benefits of these materials can be fully realized. The purpose of this article is to review the human health implications of exposure to nanoscale materials in the context of a toxicological risk evaluation, the current scope of U.S. Federal research on nanoscale materials, and selected toxicological studies associated with nanoscale materials to note emerging research in this area.

  16. Plume-stagnant slab-lithosphere interactions: Origin of the late Cenozoic intra-plate basalts on the East Eurasia margin

    Science.gov (United States)

    Kimura, Jun-Ichi; Sakuyama, Tetsuya; Miyazaki, Takashi; Vaglarov, Bogdan S.; Fukao, Yoshio; Stern, Robert J.

    2018-02-01

    Intra-plate basalts of 35-0 Ma in East Eurasia formed in a broad backarc region above the stagnant Pacific Plate slab in the mantle transition zone. These basalts show regional-scale variations in Nd-Hf isotopes. The basalts with the most radiogenic Nd-Hf center on the Shandong Peninsula with intermediate Nd-Hf at Hainan and Datong. The least radiogenic basalts occur in the perimeters underlain by the thick continental lithosphere. Shandong basalts possess isotopic signatures of the young igneous oceanic crust of the subducted Pacific Plate. Hainan and Datong basalts have isotopic signatures of recycled subduction materials with billions of years of storage in the mantle. The perimeter basalts have isotopic signatures similar to pyroxenite xenoliths from the subcontinental lithospheric mantle beneath East Eurasia. Hainan basalts exhibit the highest mantle potential temperature (Tp), while the Shandong basalts have the lowest Tp. We infer that a deep high-Tp plume interacted with the subducted Pacific Plate slab in the mantle transition zone to form a local low-Tp plume by entraining colder igneous oceanic lithosphere. We infer that the subducted Izanagi Plate slab, once a part of the Pacific Plate mosaic, broke off from the Pacific Plate slab at 35 Ma to sink into the lower mantle. The sinking Izanagi slab triggered the plume that interacted with the stagnant Pacific slab and caused subcontinental lithospheric melting. This coincided with formation of the western Pacific backarc marginal basins due to Pacific Plate slab rollback and stagnation.

  17. Effects of Basalt Fibres on Mechanical Properties of Concrete

    Directory of Open Access Journals (Sweden)

    El-Gelani A. M.

    2018-01-01

    Full Text Available This paper presents the results of an experimental program carried out to investigate the effects of Basalt Fibre Reinforced Polymers (BFRP on some fundamental mechanical properties of concrete. Basalt fibres are formed by heating crushed basalt rocks and funnelling the molten basalt through a spinneret to form basalt filaments. This type of fibres have not been widely used till recently. Two commercially available chopped basalt fibres products with different aspect ratios were investigated, which are dry basalt (GeoTech Fibre and basalt pre-soaked in an epoxy resin (GeoTech Matrix .The experimental work included compression tests on 96 cylinders made of multiple batches of concrete with varying amounts of basalt fibre additives of the two mentioned types, along with control batches containing no fibres. Furthermore, flexural tests on 24 prisms were carries out to measure the modulus of rupture, in addition to 30 prisms for average residual strength test. Results of the research indicated that use of basalt fibres has insignificant effects on compressive strength of plain concrete, where the increase in strength did not exceed about 5%. On the other hand, results suggest that the use of basalt fibres may increase the compressive strength of concrete containing fly as up top 40%. The rupture strength was increased also by 8% to 28% depending on mix and fibre types and contents. Finally, there was no clear correlation between the average residual strength and ratios of basalt fibres mixed with the different concrete batches.

  18. Geochemical characteristics of the Jos-Plateau Basalts, North ...

    African Journals Online (AJOL)

    The Jos Plateau basalts, present Zr/Nb ratios (2.4-3.0) comparable to those of the alkali basalts of the lower Benue valley, and of the Cameroon volcanic line, suggesting that they were possibly derived from the same mantle source. Keywords: Jos Plateau, alkali basalt, mantle, partial melting, incompatible elements.

  19. Basalts as probes of planetary interiors: constraints on the chemistry and mineralogy of their source regions

    International Nuclear Information System (INIS)

    Bence, A.E.; Grove, T.L.; Papike, J.J.

    1980-01-01

    Basalt magmas, derived by the partial melting of planetary interiors, have compositions that reflect the pre-accretionary history of the material from which the planet formed, the planets, subsequent evolutionary history, the chemistry and mineralogy of the source regions, and the intensive thermodynamic parameters operating at the source and emplacement sites. Studies of basalt suites from the Earth, its Moon, and the eucrite parent body reveal compositional differences intrinsic to their source regions which are, in turn, a characteristic of the planet and its formational and evolutionary history. (Auth.)

  20. Processing and Characterization of Basalt Fiber Reinforced Ceramic Composites for High Temperature Applications Using Polymer Precursors

    Science.gov (United States)

    Cox, Sarah B.; Lui, Donovan; Gou, Jihua

    2014-01-01

    The development of high temperature structural composite materials has been very limited due to the high cost of the materials and the processing needed. Ceramics can take much higher temperatures, but they are difficult to produce and form in bulk volumes. Polymer Derived Ceramics (PDCs) begin as a polymer matrix, allowing a shape to be formed and cured and then to be pyrolized in order to obtain a ceramic with the associated thermal and mechanical properties. The two PDCs used in this development are polysiloxane and polycarbosilane. Polysiloxanes contain a silicon oxycarbide backbone when pyrolized up to 1000C. Polycarbosilane, an organosilicon polymer, contain a silicon-carbon backbone; around 1200C, beta-SiC begins to crystallize. The use of basalt in structural and high temperature applications has been under development for over 50 years, yet there has been little published research on the incorporation of basalt fibers as a reinforcement in composites. Basalt is a naturally occurring material found in volcanic rock. Continuous basalt fiber reinforced PDCs have been fabricated and tested for the applicability of this composite system as a high temperature structural composite material. Thermal and mechanical testing includes oxyacetylene torch testing and three point bend testing.

  1. Comparison of mechanical properties and structural changes of continous basalt and glass fibres at elevated temperatures

    Czech Academy of Sciences Publication Activity Database

    Černý, Martin; Glogar, Petr; Goliáš, V.; Hruška, J.; Jakeš, P.; Sucharda, Zbyněk; Vávrová, I.

    2007-01-01

    Roč. 51, č. 2 (2007), s. 82-88 ISSN 0862-5468 R&D Projects: GA ČR GA106/05/0817 Institutional research plan: CEZ:AV0Z30460519 Keywords : basalt fibre * glass fibre * tensile properties Subject RIV: JH - Ceramics, Fire-Resistant Materials and Glass Impact factor: 0.488, year: 2007

  2. Processing and Characterization of Basalt Fiber Reinforced Ceramic Composites for High Temperature Applications Using Polymer Precursors

    Science.gov (United States)

    Cox, Sarah B.; Lui, Donovan; Wang, Xin; Gou, Jihua

    2014-01-01

    The development of high temperature structural composite materials has been very limited due to the high cost of the materials and the processing needed. Ceramics can take much higher temperatures, but they are difficult to produce and form in bulk volumes. Polymer Derived Ceramics (PDCs) begin as a polymer matrix, allowing a shape to be formed and cured and then to be pyrolized in order to obtain a ceramic with the associated thermal and mechanical properties. The two PDCs used in this development are polysiloxane and polycarbosilane. Polysiloxanes contain a silicon oxycarbide backbone when pyrolized up to 1000 deg C. Polycarbosilane, an organosilicon polymer, contain a silicon-carbon backbone; around 1200 deg C, Beta-SiC begins to crystallize. The use of basalt in structural and high temperature applications has been under development for over 50 years, yet there has been little published research on the incorporation of basalt fibers as a reinforcement in composites. Basalt is a naturally occurring material found in volcanic rock. Continuous basalt fiber reinforced PDCs have been fabricated and tested for the applicability of this composite system as a high temperature structural composite material. Thermal and mechanical testing includes oxyacetylene torch testing and three point bend testing.

  3. Microstructure and mechanical properties of heat resistant composites reinforced with basalt fibres

    Czech Academy of Sciences Publication Activity Database

    Glogar, Petr; Sucharda, Zbyněk; Černý, Martin; Puchegger, S.; Peterlik, H.

    2007-01-01

    Roč. 51, č. 4 (2007), s. 190-197 ISSN 0862-5468 R&D Projects: GA ČR GA106/05/0817 Institutional research plan: CEZ:AV0Z30460519 Keywords : ceramic matrix composites * thermosetting resin * basalt fibre Subject RIV: JI - Composite Materials Impact factor: 0.488, year: 2007

  4. High-level waste-basalt interactions. Annual progress report, February 1, 1977--September 30, 1977

    Energy Technology Data Exchange (ETDEWEB)

    McCarthy, G.J.; Scheetz, B.E.

    1978-05-01

    Commercial radioactive waste can be placed under ground in a basalt repository to contain significant amounts of radioactive decay heat for the first hundred or so years, which constitutes the ''thermal period'' of waste isolation, if the feasibility is determined that a basalt geology is a suitable medium for storage of radioactive wastes. Several physical-chemical changes analogous to natural geochemical processes can occur in and around this repository during the thermal period. The waste canister can act as a heat source and cause changes in the mineralogy and properties of the surrounding basalts. Geochemically, this is ''contact metamorphism.'' This phenomenon needs to be investigated because it could affect the behavior of the basalt with regard to migration of long-lived radionuclides away from the immediate repository. It is well known that even the relatively low-grade hydrothermal conditions possible in the repository (temperatures up to 400 degrees Centigrade; pressures up to 300 bars) can cause extensive modifications in rocks and minerals. At the end of the thermal period, the residue of the original waste plus the waste-basalt interaction products would constitute the actual waste form (or ''source term'') subject to the low-temperature leaching and migration processes under investigation in other laboratories. During the last eight months of fiscal year 1977, a program was initiated at The Pennsylvania State University which had as its objective the determination of the nature and implication of any chemical or mineralogical changes in, or interactions between, each candidate radioactive waste form and representative Columbia River Basalt under the various relevant repository conditions during the thermal period. Results of these investigations are given.

  5. High-level waste-basalt interactions. Annual progress report, February 1, 1977--September 30, 1977

    International Nuclear Information System (INIS)

    McCarthy, G.J.; Scheetz, B.E.

    1978-05-01

    Commercial radioactive waste can be placed under ground in a basalt repository to contain significant amounts of radioactive decay heat for the first hundred or so years, which constitutes the ''thermal period'' of waste isolation, if the feasibility is determined that a basalt geology is a suitable medium for storage of radioactive wastes. Several physical-chemical changes analogous to natural geochemical processes can occur in and around this repository during the thermal period. The waste canister can act as a heat source and cause changes in the mineralogy and properties of the surrounding basalts. Geochemically, this is ''contact metamorphism.'' This phenomenon needs to be investigated because it could affect the behavior of the basalt with regard to migration of long-lived radionuclides away from the immediate repository. It is well known that even the relatively low-grade hydrothermal conditions possible in the repository (temperatures up to 400 degrees Centigrade; pressures up to 300 bars) can cause extensive modifications in rocks and minerals. At the end of the thermal period, the residue of the original waste plus the waste-basalt interaction products would constitute the actual waste form (or ''source term'') subject to the low-temperature leaching and migration processes under investigation in other laboratories. During the last eight months of fiscal year 1977, a program was initiated at The Pennsylvania State University which had as its objective the determination of the nature and implication of any chemical or mineralogical changes in, or interactions between, each candidate radioactive waste form and representative Columbia River Basalt under the various relevant repository conditions during the thermal period. Results of these investigations are given

  6. The relationship of seismic velocity structure and surface fracture characteristics of basalt outcrops to rippability estimates

    International Nuclear Information System (INIS)

    Kay, S.E.; Dougherty, M.E.; Pelton, J.R.

    1994-01-01

    Seismic velocity has been shown in previous engineering studies to be related to the fracture characteristics and rippability of rock outcrops. However, common methods of measuring seismic velocity in outcrops do not take into account the many possible travel paths for wave propagation and the fact that velocity zones may exist within an outcrop. Presented here are the results of using raytracing inversion of first-arrival travel-time data to map P-velocity structure in basalt outcrops, and also the investigation of the relationship of the mapped velocities to observed surface fractures and hand-sample P-velocities. It is shown that basalt outcrops commonly consist of an irregular near-surface low-velocity zone underlain by higher velocity material; that velocity gradients can exist in outcrops; that hand-sample velocity measurements are typically higher than outcrop-scale measurements; and that the characteristics of surface fractures are empirically related to near-surface P-velocity. All of these findings are relevant to the estimated rippability of rock in geotechnical engineering. The data for this study are derived from eleven sites on basalt outcrops of the Troodos Ophiolite in Cyprus. The basalt types include pillow basalts, massive flows, and a pillow breccia. A commonly available raytracing inversion program (RAYINVR) was used to produce a velocity profile of each outcrop. Different velocity zones were detailed by inverting observed travel times to produce a model of outcrop velocity structure which produces rippability profiles for each outcrop. 16 refs., 9 figs

  7. Preparation of Basalt Incorporated Polyethylene Composite with Enhanced Mechanical Properties for Various Applications

    Directory of Open Access Journals (Sweden)

    Bredikhin Pavel

    2017-01-01

    Full Text Available The present article showed the possibility of increasing the complex of mechanical properties of polyolefins with dispersed mineral fillers obtained by fine grinding of basalt rocks via ball mill processing. The composites based on dispersed basalt, which were derived from Samara rock mass (Russia with rare earth elements containing, were obtained by extrusion combining the binder and filler, followed by preparation injection-molded test samples. The study of mechanical properties of materials developed showed the possibility of a significant increase in strength characteristics of different types of polyethylene: the breaking stress at static bending for HDPE can be increasing more than 60% and the impact strength by more than 4 times. In addition the incorporation of the dispersed basalt also enhanced the thermal properties of the composites (the oxygen index of HDPE increases from 19 to 25%.

  8. Study of crystallization of a basalt glass; Estudo de cristalizacao de um vidro de basalto

    Energy Technology Data Exchange (ETDEWEB)

    Nishimura, Fernando Takahiro; Hashizume, Camila Mina; Toffoli, Samuel Marcio, E-mail: toffoli@usp.b [Universidade de Sao Paulo (EP/USP), SP (Brazil). Escola Politecnica. Dept. de Engenharia Metalurgica e de Materiais

    2009-07-01

    Basalt vitreous ceramics posses industrial importance by presenting high mechanical resistance to the abrasion. It was studied the obtention and the crystallization of a glass obtained from a basalt of Campinas, Sao Paulo, Brazil, aiming to develop a material with great abrasive resistance. Fusions were made at 1400 deg Celsius in electrical oven and in alumina crucible, of fine residues of basalt mining. The obtained glass was treated in a crystallization temperature of 880 deg Celsius, determined by DSC, by various time of treatment. The present main crystalline phases, detected by XRD, were the magnesium-ferrite (MgFe{sub 2}O{sub 4}) and the diopsid Ca(Mg,Fe,Al)(Si,Al){sub 2}O{sub 6}. Analysing the density by the Archimedes methodology and the DRX it was possible to follow the crystallization kinetic up.

  9. High-Ti type N-MORB parentage of basalts from the south Andaman ...

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    basalts as sub-alkaline basalts and alkaline basalts. A few samples show basaltic andesite, trachy- basalt, or basanitic chemical composition. High-field strength element (HFSE) geochemistry sug- gests that studied basalt samples are probably derived from similar parental magmas. Al2O3/TiO2 and CaO/TiO2 ratios classify ...

  10. Experimental Alteration of Basalt to Support Interpretation of Remote Sensing and In Situ Meausrements from Mars

    Science.gov (United States)

    Bell, M. S.

    2014-01-01

    Major occurrences of hydrous alteration minerals on Mars have been found in Noachian impact craters formed in basaltic targets and detected using visible/near infrared (VNIR) spectroscopy. Until recently phyllosilicates were detected only in craters in the southern hemisphere [1, 2]. However, it has been reported that at least nine craters in the northern plains apparently excavated thick layers of lava and sediment to expose phyllosilicates [3] as well. The MER (Mars Exploration Rovers) rovers previously reported results of in situ measurement indicating the presence of alteration minerals on Mars [4,5] and it was recently reported that the Mars Curiosity rover has detected alteration phases in situ at Yellowknife Bay in Gale crater as well [6,7]. An important discovery for Mars geochronology is that the Chemistry and Mineralogy (CheMin) x-ray diffraction (XRD) instrument on Curiosity detected phyllosilicates indicating that phyllosilicate formation on Mars extended beyond the Noachian Epoch [8]. These discoveries indicate that Mars was globally altered by water in the past but does not constrain formation conditions for alteration phase occurrences, which have important implications for the evolution of the surface and the biological potential on Mars. Understanding the alteration assemblages produced by a range of conditions is vital for the interpretation of phyllosilicate spectral signatures as well as in situ measurements and to decipher the environment and evolution of early Mars. The martian surface has been intensely altered by meteorite impacts whose effects include brecciation and melting of target materials as well as the initiation of hydrothermal circulation in a hydrous target [9,10,11,12]. Impact effects may facilitate aqueous alteration of a basaltic target because the rate of silicate dissolution is a function of the degree of crystallinity, surface area, and temperature. The resultant alteration mineralogies from shocked basaltic target material

  11. Olivine and melt inclusion chemical constraints on the source of intracontinental basalts from the eastern North China Craton: Discrimination of contributions from the subducted Pacific slab

    Science.gov (United States)

    Li, Hong-Yan; Xu, Yi-Gang; Ryan, Jeffrey G.; Huang, Xiao-Long; Ren, Zhong-Yuan; Guo, Hua; Ning, Zhen-Guo

    2016-04-01

    melts from carbonated eclogite derived from subducted Pacific slab materials present in the deeper mantle. High degree melting of garnet pyroxenites from a shallower mantle source produced the early (∼23-20 Ma) higher-Si basalts. Mixing of these materials with deeper-sourced melts of carbonated mantle source produced the moderate-Si basalts. A thicker lithosphere after 9 Ma precluded melting of shallower garnet pyroxenites, so melts of the deeper carbonated mantle source are responsible for the low-Si basalts.

  12. Biogenic Mn-Oxides in Subseafloor Basalts.

    Science.gov (United States)

    Ivarsson, Magnus; Broman, Curt; Gustafsson, Håkan; Holm, Nils G

    2015-01-01

    The deep biosphere of the subseafloor basalts is recognized as a major scientific frontier in disciplines like biology, geology, and oceanography. Recently, the presence of fungi in these environments has involved a change of view regarding diversity and ecology. Here, we describe fossilized fungal communities in vugs in subseafloor basalts from a depth of 936.65 metres below seafloor at the Detroit Seamount, Pacific Ocean. These fungal communities are closely associated with botryoidal Mn oxides composed of todorokite. Analyses of the Mn oxides by Electron Paramagnetic Resonance spectroscopy (EPR) indicate a biogenic signature. We suggest, based on mineralogical, morphological and EPR data, a biological origin of the botryoidal Mn oxides. Our results show that fungi are involved in Mn cycling at great depths in the seafloor and we introduce EPR as a means to easily identify biogenic Mn oxides in these environments.

  13. Chronology and isotopic geochemistry of Apollo 14 basalts and Skaergard Gabbro, Eastern Greenland

    International Nuclear Information System (INIS)

    Dasch, E.J.

    1986-01-01

    Work completed on Apollo 14 basalts has been published. The two dates obtained from these rocks comprised the oldest and two of the three oldest ages (4.1 and 4.3 billion years) known for lunar maria basalts; thus their ages are important in understanding the moon's earliest history. Owing to the antiquity of these rocks, two more fragments have been dated as part of a second ASEE/NASA SFF program. The new ages are 3.95 and 4.12 billion years, thus further establishing and amplifying the earlier results. This work, although perhaps more interesting for its chronologic information, was begun as a test of chemical and petrographic models. Fragments of Apollo basalt were placed into five categories, based on petrologic and chemical, especially rare-earth element, composition. Isotopic studies were begun in an attempt to determine if the five groups of basalts were related by age or initial isotopic composition (isotopic composition of lava at time of extrusion). Although a few of the representatives of the five groups have the same age and/or initial strontium-isotopic composition, within the analtytical uncertainties, most apparently are unrelated. Petrologic implications of these data will be published in an appropriate journal

  14. Structural relaxation in annealed hyperquenched basaltic glasses

    DEFF Research Database (Denmark)

    Guo, Xiaoju; Mauro, John C.; Potuzak, M.

    2012-01-01

    The enthalpy relaxation behavior of hyperquenched (HQ) and annealed hyperquenched (AHQ) basaltic glass is investigated through calorimetric measurements. The results reveal a common onset temperature of the glass transition for all the HQ and AHQ glasses under study, indicating that the primary...... relaxation is activated at the same temperature regardless of the initial departure from equilibrium. The analysis of secondary relaxation at different annealing temperatures provides insights into the enthalpy recovery of HQ glasses....

  15. Hydrologic modeling of the Columbia Plateau basalts

    International Nuclear Information System (INIS)

    Dove, F.H.; Cole, C.R.; Bond, F.W.; Zimmerman, D.A.

    1982-09-01

    The Office of Nuclear Waste Isolation (ONWI) directed the Assessment of Effectiveness of Geologic Isolation Systems (AEGIS) Program to conduct a technology demonstration of current performance assessment techniques for the Department of Energy (DOE) as applied to a nuclear waste repository in the Columbia Plateau Basalts. Hypothetical repository coordinates were selected for an actual geographical setting on the Hanford Reservation in the state of Washington. Published hydrologic and geologic data used in the analyses were gathered in 1979 or earlier. The hydrologic simulation was divided into three major parts: (1) aquifer recharge calculations, (2) a regional hydrologic model, and (3) a local hydrologic model of the Pasco Basin. The presentation discusses the regional model. An estimate of the amount of water transmitted through the groundwater system was required to bound the transmissivity values and to estimate the transmissivity distributions for the deeper basalts. The multiple layer two-dimensional Variable Thickness Transient (VTT) code was selected as appropriate for the amount of data available and for the conditions existing in the regional systems. This model uses a finite difference formulation to represent the partial differential flow equation. The regional study area as defined for the VTT model was divided into 55 by 55 square pattern with each grid 5 kilometers on a side. The regional system was modeled as a held potential surface layer and two underlying basalt layers. The regional model established the boundary conditions for the hydrologic model the Pasco Basin

  16. Implementation of digital equality comparator circuit on memristive memory crossbar array using material implication logic

    Science.gov (United States)

    Haron, Adib; Mahdzair, Fazren; Luqman, Anas; Osman, Nazmie; Junid, Syed Abdul Mutalib Al

    2018-03-01

    One of the most significant constraints of Von Neumann architecture is the limited bandwidth between memory and processor. The cost to move data back and forth between memory and processor is considerably higher than the computation in the processor itself. This architecture significantly impacts the Big Data and data-intensive application such as DNA analysis comparison which spend most of the processing time to move data. Recently, the in-memory processing concept was proposed, which is based on the capability to perform the logic operation on the physical memory structure using a crossbar topology and non-volatile resistive-switching memristor technology. This paper proposes a scheme to map digital equality comparator circuit on memristive memory crossbar array. The 2-bit, 4-bit, 8-bit, 16-bit, 32-bit, and 64-bit of equality comparator circuit are mapped on memristive memory crossbar array by using material implication logic in a sequential and parallel method. The simulation results show that, for the 64-bit word size, the parallel mapping exhibits 2.8× better performance in total execution time than sequential mapping but has a trade-off in terms of energy consumption and area utilization. Meanwhile, the total crossbar area can be reduced by 1.2× for sequential mapping and 1.5× for parallel mapping both by using the overlapping technique.

  17. Nuclear waste repository in basalt: a design description

    International Nuclear Information System (INIS)

    Ritchie, J.S.; Schmidt, B.

    1982-01-01

    The conceptual design of a nuclear waste repository in basalt is described. Nuclear waste packages are placed in holes drilled into the floor of tunnels at a depth of 3700 ft. About 100 miles of tunnels are required to receive 35,000 packages. Five shafts bring waste packages, ventilation air, excavated rock, personnel, material, and services to and from the subsurface. The most important surface facility is the waste handling building, located over the waste handling shaft, where waste is received and packaged for storage. Two independent ventilation systems are provided to avoid potential contamination of spaces that do not contain nuclear waste. Because of the high temperatures at depth, an elaborate air chilling system is provided. Because the waste packages deliver a considerable amount of heat energy to the rock mass, particular attention is paid to heat transfer and thermal stress studies. 3 references, 31 figures, 3 tables

  18. Early Jurassic Carbon and Sodium Sequestration in a CAMP basalt flow

    Science.gov (United States)

    Block, K. A.; Puffer, J. H.

    2017-12-01

    The initial HTQ-type CAMP Orange Mountain Basalt flow, as well as related pillowed flows and the overlying Preakness flows, locally underwent substantial and well documented albitization, chloritization, and sulphate, carbonate, and zeolite mineralization. Layers representing at least 25 vol % of the Orange Mountain Basalt have undergone a major net increase in sodium and carbon content and a major redistribution of magnesium and calcium. Most alteration occurred during the development of a widespread early Jurassic geothermal system similar to the active system of Iceland. In both cases alteration was controlled by active circulation of basin brines through vesicular layers during rapid burial at temperatures that were kept elevated by recurring magmatism. Whole rock Na2O levels typically increased from 2.2 wt. % in unaltered layers to 3.2 wt. % in vesicular layers, and commonly reached levels exceeding 5 wt. %. The environmental implications of the removal of such massive amounts of sodium from the geothermal system on the chlorine budget and the salt content of Early Jurassic lakes are currently being evaluated. Massive amounts of carbon sequestration from the geothermal system may have mitigated an increased burden on the early Jurassic atmosphere where geothermal CO2 may have otherwise been vented at hot springs or solfataras. Calcite amygdules typically account for 5 to 10 vol. % of the vesiculated layers amounting to 66 to 132 kg of CO2 per m3 of basalt. If 25 vol. % of the 160 thick Orange Mountain Basalt is vesiculated that would equate to about 2640 to 5280 kg of CO2 per m2 of basalt. The full extent of calcite enrichment across the entire CAMP province, however, has not yet been determined.

  19. FOAM CONCRETE REINFORCEMENT BY BASALT FIBRES

    Directory of Open Access Journals (Sweden)

    Zhukov Aleksey Dmitrievich

    2012-10-01

    Full Text Available The authors demonstrate that the foam concrete performance can be improved by dispersed reinforcement, including methods that involve basalt fibres. They address the results of the foam concrete modeling technology and assess the importance of technology-related parameters. Reinforcement efficiency criteria are also provided in the article. Dispersed reinforcement improves the plasticity of the concrete mix and reduces the settlement crack formation rate. Conventional reinforcement that involves metal laths and rods demonstrates its limited application in the production of concrete used for thermal insulation and structural purposes. Dispersed reinforcement is preferable. This technology contemplates the infusion of fibres into porous mixes. Metal, polymeric, basalt and glass fibres are used as reinforcing components. It has been identified that products reinforced by polypropylene fibres demonstrate substantial abradability and deformability rates even under the influence of minor tensile stresses due to the low adhesion strength of polypropylene in the cement matrix. The objective of the research was to develop the type of polypropylene of D500 grade that would demonstrate the operating properties similar to those of Hebel and Ytong polypropylenes. Dispersed reinforcement was performed by the basalt fibre. This project contemplates an autoclave-free technology to optimize the consumption of electricity. Dispersed reinforcement is aimed at the reduction of the block settlement in the course of hardening at early stages of their operation, the improvement of their strength and other operating properties. Reduction in the humidity rate of the mix is based on the plasticizing properties of fibres, as well as the application of the dry mineralization method. Selection of optimal parameters of the process-related technology was performed with the help of G-BAT-2011 Software, developed at Moscow State University of Civil Engineering. The authors also

  20. Ultrasonic P- and S-Wave Attenuation and Petrophysical Properties of Deccan Flood Basalts, India, as Revealed by Borehole Studies

    Science.gov (United States)

    Vedanti, Nimisha; Malkoti, Ajay; Pandey, O. P.; Shrivastava, J. P.

    2018-03-01

    Petrophysical properties and ultrasonic P- and S-wave attenuation measurements on 35 Deccan basalt core specimens, recovered from Killari borehole site in western India, provide unique reference data-sets for a lesser studied Deccan Volcanic Province. These samples represent 338-m-thick basaltic column, consisting four lava flows each of Ambenali and Poladpur Formations, belonging to Wai Subgroup of the Deccan volcanic sequence. These basalt samples are found to be iron-rich (average FeOT: 13.4 wt%), but relatively poor in silica content (average SiO2: 47.8 wt%). The saturated massive basalt cores are characterized by a mean density of 2.91 g/cm3 (range 2.80-3.01 g/cm3) and mean P- and S-wave velocities of 5.89 km/s (range 5.01-6.50 km/s) and 3.43 km/s (range 2.84-3.69 km/s), respectively. In comparison, saturated vesicular basalt cores show a wide range in density (2.40-2.79 g/cm3) as well as P-wave (3.28-4.78 km/s) and S-wave (1.70-2.95 km/s) velocities. Based on the present study, the Deccan volcanic sequence can be assigned a weighted mean density of 2.74 g/cm3 and a low V p and V s of 5.00 and 3.00 km/s, respectively. Such low velocities in Deccan basalts can be attributed mainly to the presence of fine-grained glassy material, high iron contents, and hydrothermally altered secondary mineral products, besides higher porosity in vesicular samples. The measured Q values in saturated massive basalt cores vary enormously (Q p: 33-1960 and Q s: 35-506), while saturated vesicular basalt samples exhibit somewhat lesser variation in Q p (6-46) as well as Q s (5-49). In general, high-porosity rocks exhibit high attenuation, but we observed the high value of attenuation in some of the massive basalt core samples also. In such cases, energy loss is mainly due to the presence of fine-grained glassy material as well as secondary alteration products like chlorophaeite, that could contribute to intrinsic attenuation. Dominance of weekly bound secondary minerals might also be

  1. Degassing of reduced carbon from planetary basalts.

    Science.gov (United States)

    Wetzel, Diane T; Rutherford, Malcolm J; Jacobsen, Steven D; Hauri, Erik H; Saal, Alberto E

    2013-05-14

    Degassing of planetary interiors through surface volcanism plays an important role in the evolution of planetary bodies and atmospheres. On Earth, carbon dioxide and water are the primary volatile species in magmas. However, little is known about the speciation and degassing of carbon in magmas formed on other planets (i.e., Moon, Mars, Mercury), where the mantle oxidation state [oxygen fugacity (fO2)] is different from that of the Earth. Using experiments on a lunar basalt composition, we confirm that carbon dissolves as carbonate at an fO2 higher than -0.55 relative to the iron wustite oxygen buffer (IW-0.55), whereas at a lower fO2, we discover that carbon is present mainly as iron pentacarbonyl and in smaller amounts as methane in the melt. The transition of carbon speciation in mantle-derived melts at fO2 less than IW-0.55 is associated with a decrease in carbon solubility by a factor of 2. Thus, the fO2 controls carbon speciation and solubility in mantle-derived melts even more than previous data indicate, and the degassing of reduced carbon from Fe-rich basalts on planetary bodies would produce methane-bearing, CO-rich early atmospheres with a strong greenhouse potential.

  2. Some thoughts on the origin of lunar ANT-KREEP and mare basalts

    Science.gov (United States)

    Wakita, H.; Laul, J. C.; Schmitt, R. A.

    1975-01-01

    It is suggested that a series of ANT (anorthosite-norite-troctolite)-KREEP type rocks and the source material for mare basalts sampled by Apollo 11, 12, 15, and 17 may have been derived from a common magmatic differentiation. This differentiation is studied on the basis of a model which proposes that, in the early history of the moon, extensive melting occurred in the outer lunar shell and a magma layer of 100-200 km was formed. The presence of a residual liquid which has not yet been sampled is suspected between high-K KREEP and the Apollo 11 basalt materials. This residual liquid would have a FeO/MgO ratio greater than one and would be significantly enriched in apatite, zircon, K-feldspar, and ilmenite minerals.

  3. Basaltic rocks behavior of the Corrientes and Entre Rios province from the alcali silice reaction

    International Nuclear Information System (INIS)

    Marfil, S.; Batic, O.; Grecco, L.; Falcone, D.

    2010-01-01

    This work is about the basaltic rocks deposits in Mesopotamia - Argentina. This material is used for dikes, flooring and art . In several of them has been developed expansive processes associated with alkali - silica reaction such as pavements of some routes. In order to evaluate the behavior of these rocks their are obtained samples from the quarries using standard methods such as petrographic, rod accelerated and dissolved silica agree with the IRA M standards

  4. Development of Braided Basalt FRP Rebar for Reinforcement of Concrete Structures

    OpenAIRE

    Antonopoulou, Sofia; McNally, Ciaran; Byrne, Greg

    2016-01-01

    In recent years, the development and use of Fibre Reinforced Polymer composite materials in infrastructure have gained increasing attention worldwide. More specifically, natural mineral fibres such as basalt are currently being developed and are showing promising properties. Within an appropriate polymer matrix, their use as reinforcement in concrete structures offers performance benefits related to their environmentally friendly and non-corrodible nature. In particular, BFRPs have the potent...

  5. Wellbore cement fracture evolution at the cement–basalt caprock interface during geologic carbon sequestration

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Hun Bok; Kabilan, Senthil; Carson, James P.; Kuprat, Andrew P.; Um, Wooyong; Martin, Paul F.; Dahl, Michael E.; Kafentzis, Tyler A.; Varga, Tamas; Stephens, Sean A.; Arey, Bruce W.; Carroll, KC; Bonneville, Alain; Fernandez, Carlos A.

    2014-08-07

    Composite Portland cement-basalt caprock cores with fractures, as well as neat Portland cement columns, were prepared to understand the geochemical and geomechanical effects on the integrity of wellbores with defects during geologic carbon sequestration. The samples were reacted with CO2-saturated groundwater at 50 ºC and 10 MPa for 3 months under static conditions, while one cement-basalt core was subjected to mechanical stress at 2.7 MPa before the CO2 reaction. Micro-XRD and SEM-EDS data collected along the cement-basalt interface after 3-month reaction with CO2-saturated groundwater indicate that carbonation of cement matrix was extensive with the precipitation of calcite, aragonite, and vaterite, whereas the alteration of basalt caprock was minor. X-ray microtomography (XMT) provided three-dimensional (3-D) visualization of the opening and interconnection of cement fractures due to mechanical stress. Computational fluid dynamics (CFD) modeling further revealed that this stress led to the increase in fluid flow and hence permeability. After the CO2-reaction, XMT images displayed that calcium carbonate precipitation occurred extensively within the fractures in the cement matrix, but only partially along the fracture located at the cement-basalt interface. The 3-D visualization and CFD modeling also showed that the precipitation of calcium carbonate within the cement fractures after the CO2-reaction resulted in the disconnection of cement fractures and permeability decrease. The permeability calculated based on CFD modeling was in agreement with the experimentally determined permeability. This study demonstrates that XMT imaging coupled with CFD modeling represent a powerful tool to visualize and quantify fracture evolution and permeability change in geologic materials and to predict their behavior during geologic carbon sequestration or hydraulic fracturing for shale gas production and enhanced geothermal systems.

  6. Continental Flood Basalts of Bennett Island, East Siberian Sea: High Arctic Geodynamics

    Science.gov (United States)

    Tegner, Christian; Pease, Victoria

    2014-05-01

    Volcanism provides a means of tracing mantle melting events and crustal evolution. The High Arctic includes a rich portfolio of volcanic rocks outcropping in the Circum-Arctic borderlands and imaged geophysically beneath the Alpha-Mendeleev Ridge that have been lumped together as a High-Arctic Large Igneous Province (HALIP). However, the ages (c. 440-60 Ma) and compositions (tholeiitic-alkaline-calc-alkaline) reported varies considerably and geological correlations remain elusive. One of the possible correlative events is the formation of continental flood basalts and sills in the Canadian Arctic Islands, Svalbard, Franz Josef Land and Bennett Island. These flood basalts have previously been linked to mantle plume melting and may represent a short-lived LIP event at c. 124-122 Ma. We present new data for a 350 m thick continental flood basalt succession at Bennett Island examined during fieldwork in Septemer 2013 on a joint Russian (VSEGEI) - Swedish (SWEDARCTIC) expedition to the De Long Archipelago. This volcanic succession is composed of 20 near-horisontal, undeformed flow units overlying a thin sedimentary succession of Cretaceous age (?) including coal seams and possibly volcaniclastic material that, in turn, unconformably overlies a more steeply dipping succession of Cambrian and Ordovician sediments. The flows are thinnest (c. 2-10 m) and aphyric to very-sparsely olivine-phyric in the lower portion. In contrast, the flows in the upper portion are thicker (>20 m) and aphyric to sparsely plagioclase-phyric. We will discuss new petrographic and compositional data for the Bennett Island flood basalts, possibly including new U-Pb age data. The aim is to evaluate their petrogenesis, to discuss their possible correlation to the flood basalt and sill successions of the Canadian Arctic Islands, Svalbard and Franz Josef Land and evaluate the geodynamic evolution of the High Arctic.

  7. Constructibility issues associated with a nuclear waste repository in basalt

    International Nuclear Information System (INIS)

    Turner, D.A.

    1981-01-01

    This report contains the text and slide reproductions of a speech on nuclear waste disposal in basalt. The presentation addresses the layout of repository access shafts and subsurface facilities resulting from the conceptual design of a nuclear repository in basalt. The constructibility issues that must be resolved prior to construction are described

  8. Hydrogeology of the basalts in the Uruguayan NW

    International Nuclear Information System (INIS)

    Hausman, A.; Fernandez, A.

    1967-01-01

    This work is about the hydrogeological aspects in the NW Uruguayan basaltic area. The results of this research are the main geological, morphological and hydrogeological aspects of the area as well as the characteristics and the color of the basalt and sandstones

  9. A note on incipient spilitisation of central Indian basin basalts

    Digital Repository Service at National Institute of Oceanography (India)

    Karisiddaiah, S.M.; Iyer, S.D.

    of chlorite, epidote and opaques. The oxide variation plots indicate a mid-ocean ridge basalt trend for the samples, which have been spilitised to varying degrees. It is suggested that the basalts formed as a result of a fissure type of eruption along...

  10. Mineral chemistry of Pangidi basalt flows from Andhra Pradesh

    Indian Academy of Sciences (India)

    Pangidi basalts follow the QFM buffer curve which indicates the more evolved tholeiitic composition. This suggests the parent tholeiitic magma suffered limited fractionation at high temperature under increasing oxygen fugacity in lower basalt flow and more fractionation at medium to lower temperatures under decreasing ...

  11. Basalt Weathering and the Volatile Budget of Early Mars

    Science.gov (United States)

    Baker, L. L.

    2017-10-01

    Basalt weathering on Earth consumes CO2 and water and may have affected terrestrial climate. I apply a mass balance derived from terrestrial data to examine the effect surficial basalt weathering may have had on the CO2 budget of early Mars.

  12. Influence of basalt/groundwater interactions on radionuclide migration

    International Nuclear Information System (INIS)

    Vandegrift, G.F.

    1984-01-01

    The work presented here is a partial summary of the experimental results obtained in the Laboratory Analog Program. Two aspects of this effort are (1) the interaction between simulated basaltic groundwater and basalt fissures that were either freshly cleaved or laboratory altered by hydrothermal treatment with the simulated groundwater and (2) the effect of this interaction on radionuclide migration through these basalt fissures. The following conclusions of this study bear heavily on the predicted safety of a basalt repository: Sorption properties of freshly fissured basalt and naturally aged basalt are quite different for different chemical species. Analog experiments predict that aged basalt would be an effective retarder of cesium, but would be much less so for actinide elements. Distribution ratios measured from batch experiments with finely ground rock samples (presenting unaltered rock surfaces) are not a reliable means of predicting radionuclide migration in geological repositories. As the near-repository area is resaturated by groundwater, its ability to retard actinide migration will be degraded with time. Disturbing the natural flow of groundwater through the repository area by constructing and backfilling the repository will modify the composition of groundwater. This modified groundwater is likely to interact with and to modify naturally aged basalt surfaces downstream from the repository

  13. Rapid solubility and mineral storage of CO2 in basalt

    DEFF Research Database (Denmark)

    Gislason, Sigurdur R.; Broecker, W.S.; Gunnlaugsson, E.

    2014-01-01

    rich in divalent metal cations such as basalts and ultra-mafic rocks. We have demonstrated the dissolution of CO2 into water during its injection into basalt leading to its geologic solubility storage in less than five minutes and potential geologic mineral storage within few years after injection [1...

  14. Hydrothermal interactions of cesium and strontium phases from spent unreprocessed fuel with basalt phases and basalts

    Energy Technology Data Exchange (ETDEWEB)

    Komarneni, S.; Scheetz, B.E.; McCarthy, G.J.; Coons, W.E.

    1980-03-01

    This investigation is a segment of an extensive research program aimed at investigating the feasibility of long-term, subsurface storage of commercial nuclear waste. Specifically, it is anticipated that the waste will be housed in a repository mined from the basalt formations which lie beneath the Hanford Site. The elements monitored during the present experiments were Cs and Sr. These two elements represent significant biohazards if released from a repository and are the major heat producing radionuclides present in commercial radioactive waste. Several Cs phases and/or solutions were reacted with either isolated basalt phases or bulk-rock basalt, and the resulting solids and solutions were analyzed. The hydrothermal reactivity of SrZrO/sub 3/, which is believed to be a probable host for Sr in SFE was investigated. While so far no evidence exists which indicates that Sr is present in a water soluble phase in spent fuel elements (SFE), detailed investigation of a potential hazard is warranted. This investigation has determined that some Cs compounds likely to be stable components of spent fuel (i.e., CsOH, Cs/sub 2/MoO/sub 4/, Cs/sub 2/U/sub 2/O/sub 7/) have significant hydrothermal solubilities. These solubilities are greatly decreased in the presence of basalt and/or basalt minerals. The decrease in the amount of Cs in solution results from reactions which form pollucite and/or CsAlSiO/sub 4/, with the production of pollucite exceeding that of CsAlSiO/sub 4/. Dissolution of ..beta..-Cs/sub 2/U/sub 2/O/sub 7/ implies solubilizing a uranium species to an undetermined extent. The production of schoepite (UO/sub 3/.3H/sub 2/O) during some experiments containing basalt phases, indicates a tendency to oxidize U/sup 4 +/ to U/sup 6 +/. When diopside (nominally CaMgSi/sub 2/O/sub 6/) and ..beta..-Cs/sub 2/U/sub 2/O/sub 7/ were hydrothermally reacted, at 300/sup 0/C both UO/sub 2/ and UO/sub 3/.3H/sub 2/O were produced. Results of experiments on SrZrO/sub 3/ show it to be

  15. Hydrothermal interactions of cesium and strontium phases from spent unreprocessed fuel with basalt phases and basalts

    International Nuclear Information System (INIS)

    Komarneni, S.; Scheetz, B.E.; McCarthy, G.J.; Coons, W.E.

    1980-03-01

    This investigation is a segment of an extensive research program aimed at investigating the feasibility of long-term, subsurface storage of commercial nuclear waste. Specifically, it is anticipated that the waste will be housed in a repository mined from the basalt formations which lie beneath the Hanford Site. The elements monitored during the present experiments were Cs and Sr. These two elements represent significant biohazards if released from a repository and are the major heat producing radionuclides present in commercial radioactive waste. Several Cs phases and/or solutions were reacted with either isolated basalt phases or bulk-rock basalt, and the resulting solids and solutions were analyzed. The hydrothermal reactivity of SrZrO 3 , which is believed to be a probable host for Sr in SFE was investigated. While so far no evidence exists which indicates that Sr is present in a water soluble phase in spent fuel elements (SFE), detailed investigation of a potential hazard is warranted. This investigation has determined that some Cs compounds likely to be stable components of spent fuel (i.e., CsOH, Cs 2 MoO 4 , Cs 2 U 2 O 7 ) have significant hydrothermal solubilities. These solubilities are greatly decreased in the presence of basalt and/or basalt minerals. The decrease in the amount of Cs in solution results from reactions which form pollucite and/or CsAlSiO 4 , with the production of pollucite exceeding that of CsAlSiO 4 . Dissolution of β-Cs 2 U 2 O 7 implies solubilizing a uranium species to an undetermined extent. The production of schoepite (UO 3 .3H 2 O) during some experiments containing basalt phases, indicates a tendency to oxidize U 4+ to U 6+ . When diopside (nominally CaMgSi 2 O 6 ) and β-Cs 2 U 2 O 7 were hydrothermally reacted, at 300 0 C both UO 2 and UO 3 .3H 2 O were produced. Experiments on SrZrO 3 show it to be an unreactive phase

  16. Petrology of offshore basalts of Bombay harbour area, west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Karisiddaiah, S.M.

    glass are conspicuous. The chemical data indicate that the basalts are tholeiitic. Secondary minerals encountered support the view that the basalts are spilitised. Basalts of this area show affinities to both continental and oceanic types especially...

  17. Simulation and Experimental Determination of Technological Liquid Molding Parameters of Tubing Basalt Insulation

    Directory of Open Access Journals (Sweden)

    Yu. V. Badanina

    2015-01-01

    is proved that in order to reduce a manufacturing time of long-length cylindrical shells from short basalt fibers by liquid filtration it is necessary to use the scheme of their molding from a plane of the cylinder element. Taking into account the thermal characteristics of basalt fibers and highly porous structure of the thermal insulation on the received samples are determined the real porosity, density of material and the thickness of the tubing pipe coatings.

  18. Investigating the Influence of Waste Basalt Powder on Selected Properties of Cement Paste and Mortar

    Science.gov (United States)

    Dobiszewska, Magdalena; Beycioğlu, Ahmet

    2017-10-01

    Concrete is the most widely used man-made construction material in civil engineering applications. The consumption of cement and thus concrete, increases day by day along with the growth of urbanization and industrialization and due to new developments in construction technologies, population growing, increasing of living standard. Concrete production consumes much energy and large amounts of natural resources. It causes environmental, energy and economic losses. The most important material in concrete production is cement. Cement industry contributes to production of about 7% of all CO2 generated in the world. Every ton of cement production releases nearly one ton of CO2 to atmosphere. Thus the concrete and cement industry changes the environment appearance and influences it very much. Therefore, it has become very important for construction industry to focus on minimizing the environmental impact, reducing energy consumption and limiting CO2 emission. The need to meet these challenges has spurred an interest in the development of a blended Portland cement in which the amount of clinker is reduced and partially replaced with mineral additives - supplementary cementitious materials (SCMs). Many researchers have studied the possibility of using another mineral powder in mortar and concrete production. The addition of marble dust, basalt powder, granite or limestone powder positively affects some properties of cement mortar and concrete. This paper presents an experimental study on the properties of cement paste and mortar containing basalt powder. The basalt powder is a waste emerged from the preparation of aggregate used in asphalt mixture production. Previous studies have shown that analysed waste used as a fine aggregate replacement, has a beneficial effect on some properties of mortar and concrete, i.e. compressive strength, flexural strength and freeze resistance also. The present study shows the results of the research concerning the modification of cement

  19. Experimental shock metamorphism of terrestrial basalts: Agglutinate-like particle formation, petrology, and magnetism

    Science.gov (United States)

    Badyukov, Dmitrii D.; Bezaeva, Natalia S.; Rochette, Pierre; Gattacceca, Jérôme; Feinberg, Joshua M.; Kars, Myriam; Egli, Ramon; Raitala, Jouko; Kuzina, Dilyara M.

    2018-01-01

    Hypervelocity impacts occur on bodies throughout our solar system, and play an important role in altering the mineralogy, texture, and magnetic properties in target rocks at nanometer to planetary scales. Here we present the results of hypervelocity impact experiments conducted using a two-stage light-gas gun with 5 mm spherical copper projectiles accelerated toward basalt targets with 6 km s-1 impact velocities. Four different types of magnetite- and titanomagnetite-bearing basalts were used as targets for seven independent experiments. These laboratory impacts resulted in the formation of agglutinate-like particles similar in texture to lunar agglutinates, which are an important fraction of lunar soil. Materials recovered from the impacts were examined using a suite of complementary techniques, including optical and scanning electron microscopy, micro-Raman spectroscopy, and high- and low-temperature magnetometry, to investigate the texture, chemistry, and magnetic properties of newly formed agglutinate-like particles and were compared to unshocked basaltic parent materials. The use of Cu-projectiles, rather than Fe- and Ni-projectiles, avoids magnetic contamination in the final shock products and enables a clearer view of the magnetic properties of impact-generated agglutinates. Agglutinate-like particles show shock features, such as melting and planar deformation features, and demonstrate shock-induced magnetic hardening (two- to seven-fold increases in the coercivity of remanence Bcr compared to the initial target materials) and decreases in low-field magnetic susceptibility and saturation magnetization.

  20. Draft site characterization analysis of the site characterization report for the Basalt Waste Isolation Project, Hanford, Washington Site. Main report and Appendices A through D

    International Nuclear Information System (INIS)

    1983-03-01

    On November 12, 1982, the US Department of Energy submitted to the US Nuclear Regulatory Commission the Site Characterization Report for the Basalt Waste Isolation Project (DOE/RL 82-3). The Basalt Waste Isolation Project is located on DOE's Hanford Reservation in the State of Washington. NUREG-0960 contains the detailed analysis, by the NRC staff, of the site characterization report. Supporting technical material is contained in Appendices A through W

  1. The release of organic material from clay based buffer materials and its potential implications for radionuclide transport

    International Nuclear Information System (INIS)

    Vilks, P.; Stroes-Gascoyne, S.; Goulard, M.; Haveman, S.A.; Bachinski, D.B.

    1998-01-01

    In the Canadian nuclear fuel waste disposal concept used fuel would be placed in corrosion resistant containers which would be surrounded by clay-based buffer and backfill materials in an engineered vault excavated at 500 to 1000 m depth in crystalline rock formations in the Canadian shield. Organic substances could affect radionuclide mobility due to the effects of redox and complexation reactions that increase solubility and alter mobility. The purpose of this study was to determine whether the buffer and backfill materials, proposed for use in a disposal vault, contain organics that could be leached by groundwater in large enough quantities to affect radionuclide mobility within the disposal vault and surrounding geosphere complex. Buffer material, made from a mixture of 50 wt.% Avonlea sodium bentonite and 50 wt.% silica sand, was extracted with deionized water to determine the release of dissolved organic carbon (DOC), humic acid and fulvic acid. The effect of radiation and heat from the used fuel was simulated by treating samples of buffer before leaching to various amounts of heat (60 and 90 C) for periods of 2, 4 and 6 weeks, and to ionizing radiation with doses of 25 kGy and 50 kGy. The results showed that groundwater would leach significant amounts of organics from buffer that complex with radionuclides such as the actinides, potentially affecting their solubility and transport within the disposal vault and possibly the surrounding geosphere. In addition, the leached organics would likely stimulate microbial growth by several orders of magnitude. Heating and radiation affect the amount and nature of leachable organics. (orig.)

  2. Rheological evolution of planetary basalts during cooling and crystallization

    Science.gov (United States)

    Sehlke, Alexander

    Basaltic lavas cover large portions of the surface of the Earth and other planets and moons. Planetary basalts are compositionally different from terrestrial basalts, and show a variety of unique large-scale lava flow morphologies unobserved on Earth. They are usually assumed to be much more fluid than basalts on Earth, such as Hawaiian basalt, but their rheology is largely unknown. I synthesized several synthetic silicate melts representing igneous rock compositions of Mars, Mercury, the Moon, Io and Vesta. I measured their viscosity, as well as several terrestrial lavas including Hawaiian basalt, by concentric cylinder and parallel plate viscometry. Planetary melts cover a wide range of viscosity at their liquidus, overlapping with terrestrial basaltic melts. I derived a new viscosity model that is based on the Adam-Gibbs theory of structural relaxation, predicting these viscosities much more accurately than previously published viscosity models. During crystallization, the rheological behavior changes from Newtonian to pseudoplastic. Combining rheology experiments with field observations, the rheological conditions of the pahoehoe to `a`a morphological transition for Hawaiian basalt were determined in strain rate-viscosity space. This transition occurs at temperatures around 1185+/-15°C. For Mercurian lavas, this transition is predicted to occur at higher temperatures around 1250+/-30°C. We find that the rheology of these lavas is broadly similar to terrestrial ones, suggesting that the large smooth volcanic plains observed on Mercury's northern hemisphere are due to flood basalt volcanism rather than unusually fluid lavas. We also show that KREEP lavas, a type of basalt associated with sinuous rilles on the lunar surface, is more likely to form rilles through levee construction, as the high and rapidly increasing viscosity prohibits sufficient thermo-mechanical erosion.

  3. Petrology of Gakkel Ridge Basalts: Preliminary Results

    Science.gov (United States)

    Langmuir, C. H.; Lehnert, K.; Goldstein, S. L.; Michael, P.; Graham, D.; Schramm, B.

    2001-12-01

    The Gakkel Ridge offers the opportunity for a direct experiment in mantle melting and ridge dynamics. It is the slowest spreading ridge on the Earth, with a progressive change in spreading rate from 15mm/yr at the western end to 7mm/yr at the eastern end. No transform faults disrupt the melting regime, and spreading rate alone would appear to be the primary variable. During the AMORE2001 expedition of USCGC Healy and RV Polarstern, more than one hundred sampling stations were successfully completed mid-way through the cruise, with precise locations on new multibeam bathymetric charts (Kurras et al, Gauger et al, this meeting). More than 100 samples were analyzed on board for major elements, Sr and Ba by direct current plasma spectrometry. Because the cruise track encompasses a double-pass along most of the ridge, the on board data permitted testing of hypotheses formulated on the first pass by further sampling on the second pass. Models for the effect of decreasing spreading rate on melt composition predict progressively smaller extents of melting at greater depths eastward along the ridge. Instead, the ridge contains three distinct tectono-magmatic regimes. In the west, well-defined linear volcanic ridges occupy the center of the rift valley. The basalts exhibit a ''slow spreading local trend'' of negative correlation between Fe8 and Si8 and positive correlation between Na8 and Fe8. There is a well-defined geochemical gradient from more enriched incompatible trace element compositions in the west to depleted compositions in the east. At the eastern terminus of this region there are small volcanic cones with chemical compositions rare or unique among MORB. Samples with high MgO contain high TiO2 and Sr (3% and 200 ppm), and low SiO2 and Ba (46-47% and 20 ppm ). The low SiO2 and exceptionally high FeO (12%) suggest high pressures of melting. The high Sr and TiO2 but very low Ba of these samples suggest they were derived by very low extents of melting of a depleted

  4. Vesiculation of basaltic magma during eruption

    Science.gov (United States)

    Mangan, Margaret T.; Cashman, Katharine V.; Newman, Sally

    1993-01-01

    Vesicle size distributions in vent lavas from the Pu'u'O'o-Kupaianaha eruption of Kilauea volcano are used to estimate nucleation and growth rates of H2O-rich gas bubbles in basaltic magma nearing the earth's surface (≤120 m depth). By using well-constrained estimates for the depth of volatile exsolution and magma ascent rate, nucleation rates of 35.9 events ⋅ cm-3 ⋅ s-1 and growth rates of 3.2 x 10-4cm/s are determined directly from size-distribution data. The results are consistent with diffusion-controlled growth as predicted by a parabolic growth law. This empirical approach is not subject to the limitations inherent in classical nucleation and growth theory and provides the first direct measurement of vesiculation kinetics in natural settings. In addition, perturbations in the measured size distributions are used to examine bubble escape, accumulation, and coalescence prior to the eruption of magma.

  5. Strontium stable isotope behaviour accompanying basalt weathering

    Science.gov (United States)

    Burton, K. W.; Parkinson, I. J.; Gíslason, S. G. R.

    2016-12-01

    The strontium (Sr) stable isotope composition of rivers is strongly controlled by the balance of carbonate to silicate weathering (Krabbenhöft et al. 2010; Pearce et al. 2015). However, rivers draining silicate catchments possess distinctly heavier Sr stable isotope values than their bedrock compositions, pointing to significant fractionation during weathering. Some have argued for preferential release of heavy Sr from primary phases during chemical weathering, others for the formation of secondary weathering minerals that incorporate light isotopes. This study presents high-precision double-spike Sr stable isotope data for soils, rivers, ground waters and estuarine waters from Iceland, reflecting both natural weathering and societal impacts on those environments. The bedrock in Iceland is dominantly basaltic, d88/86Sr ≈ +0.27, extending to lighter values for rhyolites. Geothermal waters range from basaltic Sr stable compositions to those akin to seawater. Soil pore waters reflect a balance of input from primary mineral weathering, precipitation and litter recycling and removal into secondary phases and vegetation. Rivers and ground waters possess a wide range of d88/86Sr compositions from +0.101 to +0.858. Elemental and isotope data indicate that this fractionation primarily results from the formation or dissolution of secondary zeolite (d88/86Sr ≈ +0.10), but also carbonate (d88/86Sr ≈ +0.22) and sometimes anhydrite (d88/86Sr ≈ -0.73), driving the residual waters to heavier or lighter values, respectively. Estuarine waters largely reflect mixing with seawater, but are also be affected by adsorption onto particulates, again driving water to heavy values. Overall, these data indicate that the stability and nature of secondary weathering phases, exerts a strong control on the Sr stable isotope composition of silicate rivers. [1] Krabbenhöft et al. (2010) Geochim. Cosmochim. Acta 74, 4097-4109. [2] Pearce et al. (2015) Geochim. Cosmochim. Acta 157, 125-146.

  6. Suitability of asthma education materials for school-age children: Implications for health literacy.

    Science.gov (United States)

    Tzeng, Yu-Fen; Gau, Bih-Shya

    2017-08-09

    To investigate the suitability of asthma education materials for school-age children with asthma and elucidate how these children used their health-literacy abilities to identify whether the materials can be accepted, comprehended and applied. Effective asthma self-management education is influenced by the suitability of materials and an individual's health literacy. A mixed-method research design was developed using quantitative and qualitative surveys. The suitability of the materials was assessed on the basis of the Chinese version of the Suitability Assessment of Materials by five experts. In addition, five school-age children (age: 8-12 years) were recruited and interviewed. In total, 25 pieces of asthma education material for children were collected. On the basis of their type, the materials were categorised as nine brochures, 11 leaflets and five videos. Of the 25 materials, 17 were rated as superior materials, whereas eight were rated as adequate materials. The suitability scores of the video-based materials were significantly higher than those of the brochures and leaflets (p = .006). One print material was considered to have a reading level suitable for fifth-grade or younger children, whereas the remaining materials were considered suitable for sixth-grade or older children. The following six health-literacy domains were identified: recognising asthma through body knowledge, posing reflective questions, identifying self-care difficulties, receiving adult guidance, learning with enjoyment and addressing learning requirements. The video-based materials had integrated content and were appealing to children. Cartoon animations, interactive computer games, and skill demonstrations may enhance learning stimulation and motivation and increase learning effects in children. The present results may help healthcare providers to understand children's capacities to manage their disease, effectively address children's requirements and function as a key resource for

  7. BASALT A: Basaltic Terrains in Idaho and Hawaii as Planetary Analogs for Mars Geology and Astrobiology

    Science.gov (United States)

    Hughes, Scott S.; Haberle, Christopher W.; Nawotniak, Shannon E. Kobs; Sehlke, Alexander; Garry, W. Brent; Elphic, Richard C.; Payler, Sam J.; Stevens, Adam H.; Cockell, Charles S.; Brady, Allyson L.; hide

    2018-01-01

    Assessments of field research target regions are described within two notably basaltic geologic provinces as Earth analogs to Mars. Regions within the eastern Snake River Plain of Idaho and the Big Island of Hawaii, USA, provinces that represent analogs of present-day and early Mars, respectively, were evaluated on the basis of geologic settings, rock lithology and geochemistry, rock alteration, and climate. Each of these factors provide rationale for the selection of specific targets for field research in five analog target regions: (1) Big Craters and (2) Highway lava flows at Craters of the Moon National Monument and Preserve, Idaho; and (3) Mauna Ulu low shield, (4) Kilauea Iki lava lake and (5) Kilauea caldera in the Kilauea Volcano summit region and the East Rift Zone of Hawaii. Our evaluation of compositional and textural differences, as well as the effects of syn- and post-eruptive rock alteration, shows that the basaltic terrains in Idaho and Hawaii provide a way to characterize the geology and major geologic substrates that host biological activity of relevance to Mars exploration. This work provides the foundation to better understand the scientific questions related to the habitability of basaltic terrains, the rationale behind selecting analog field targets, and their applicability as analogs to Mars.

  8. Petrogenesis of basalt-trachyte lavas from Olmoti Crater, Tanzania

    Science.gov (United States)

    Mollel, Godwin F.; Swisher, Carl C., III; McHenry, Lindsay J.; Feigenson, Mark D.; Carr, Michael J.

    2009-08-01

    Olmoti Crater is part of the Plio-Pleistocene Ngorongoro Volcanic Highland (NVH) in northern Tanzania to the south of Gregory Rift. The Gregory Rift is part of the eastern branch of the East African Rift System (EARS) that stretches some 4000 km from the Read Sea and Gulf of Aden in the north to the Zambezi River in Mozambique. Here, we (1) characterize the chemistry and mineral compositions of lavas from Olmoti Crater, (2) determine the age and duration of Olmoti volcanic activity through 40Ar/ 39Ar dating of Olmoti Crater wall lavas and (3) determine the genesis of Olmoti lavas and the relationship to other NVH and EARS volcanics and (4) their correlation with volcanics in the Olduvai and Laetoli stratigraphic sequences. Olmoti lavas collected from the lower part of the exposed crater wall section (OLS) range from basalt to trachyandesite whereas the upper part of the section (OUS) is trachytic. Petrography and major and trace element data reflect a very low degree partial melt origin for the Olmoti lavas, presumably of peridotite, followed by extensive fractionation. The 87Sr/ 86Sr data overlap whereas Nd and Pb isotope data are distinct between OLS and OUS samples. Interpretation of the isotope data suggests mixing of enriched mantle (EM I) with high-μ-like reservoirs, consistent with the model of Bell and Blenkinsop [Bell, K., Blenkinsop, J., 1987. Nd and Sr isotopic compositions of East African carbonatites: implications for mantle heterogeneity. Geology 5, 99-102] for East African carbonatite lavas. The isotope ratios are within the range of values defined by Oceanic Island Basalt (OIB) globally and moderate normalized Tb/Yb ratios (2.3-1.6) in these lavas suggest melting in the lithospheric mantle consistent with other studies in the region. 40Ar/ 39Ar incremental-heating analyses of matrix and anorthoclase separates from Olmoti OLS and OUS lavas indicate that volcanic activity was short in duration, lasting ˜200 kyr from 2.01 ± 0.03 Ma to 1.80 ± 0

  9. Effective Carbon Dioxide Photoreduction over Metals (Fe-, Co-, Ni-, and Cu- Incorporated TiO2/Basalt Fiber Films

    Directory of Open Access Journals (Sweden)

    Jeong Yeon Do

    2016-01-01

    Full Text Available Mineralogical basalt fibers as a complementary adsorbent were introduced to improve the adsorption of CO2 over the surfaces of photocatalysts. TiO2 photocatalysts (M-TiO2 incorporated with 5.0 mol.% 3d-transition metals (Fe, Co, Ni, and Cu were prepared using a solvothermal method and mixed with basalt fibers for applications to CO2 photoreduction. The resulting 5.0 mol.% M-TiO2 powders were characterized by X-ray diffraction, scanning electron microscopy, ultraviolet-visible spectroscopy, photoluminescence, Brunauer, Emmett, and Teller surface area, and CO2-temperature-programmed desorption. A paste composed of two materials was coated and fixed on a Pyrex plate by a thermal treatment. The 5.0 mol.% M-TiO2/basalt fiber films increased the adsorption of CO2 significantly, indicating superior photocatalytic behavior compared to pure TiO2 and basalt fiber films, and produced 158~360 μmol gcat-1 L−1 CH4 gases after an 8 h reaction. In particular, the best performance was observed over the 5.0 mol.% Co-TiO2/basalt fiber film. These results were attributed to the effective CO2 gas adsorption and inhibition of photogenerated electron-hole pair recombination.

  10. Breaking of macroscopic centric symmetry in paraelectric phases of ferroelectric materials and implications for flexoelectricity

    Science.gov (United States)

    Biancoli, Alberto; Fancher, Chris M.; Jones, Jacob L.; Damjanovic, Dragan

    2015-02-01

    A centrosymmetric stress cannot induce a polar response in centric materials; piezoelectricity is, for example, possible only in non-centrosymmetric structures. An exception is metamaterials with shape asymmetry, which may be polarized by stress even when the material is centric. In this case the mechanism is flexoelectricity, which relates polarization to a strain gradient. The flexoelectric response scales inversely with size, thus a large effect is expected in nanoscale materials. Recent experiments in polycrystalline, centrosymmetric perovskites (for example, (Ba, Sr)TiO3) have indicated values of flexoelectric coefficients that are orders of magnitude higher than theoretically predicted, promising practical applications based on bulk materials. We show that materials with unexpectedly large flexoelectric response exhibit breaking of the macroscopic centric symmetry through inhomogeneity induced by the high-temperature processing. The emerging electro-mechanical coupling is significant and may help to resolve the controversy surrounding the large apparent flexoelectric coefficients in this class of materials.

  11. Spectral measurements of returned spacecraft surfaces and the implications for space debris material measurements

    Science.gov (United States)

    Jorgensen, K.; Culp, R. D.; Clark, R. N.

    2001-10-01

    Knowledge of the physical properties of orbital debris is necessary for modeling the debris environment. Current methods determine the size and mass of orbital debris based on knowledge or assumption of the material type of the piece. By using spectroscopy, one can determine the material type of the piece by comparing the absorption features of its spectra to that of lab spectra for given materials. The goal of this research is not to improve the models themselves, but to improve the information others use to make the models. In order to determine the effects of the space environment on the reflectance spectra of spacecraft materials, researchers measured materials from returned spacecraft. Measurements of material degradation for returned missions from the Long Duration Exposure Facility (LDEF) are documented herein. When the spectra of returned spacecraft materials were compared with the pre-flight laboratory spectra degradation in the samples were seen mostly in the visible wavelengths, while the samples showed similar features in the near-infrared. Overall, the results displayed less degradation on the spaceflight samples than anticipated. The spectral measurements of returned spacecraft materials lent credence to continuing the study of determining the material type of orbital debris using spectroscopy.

  12. Statement of John H. Anttonen, Project Manager, Basalt Waste Isolation Project, Richland Operations Office, Department of Energy

    International Nuclear Information System (INIS)

    Anon.

    1987-01-01

    My name is John Anttonen and I am the Project Manager for the Basalt Waste Isolation Project (BWIP) at the Department of Energy Richland Operation Office. The responsibilities of may office are to manage the day-to-day activities of the site suitability investigations of the basalt formations at the Hanford Site, a Department complex that is involved in a variety of national missions, including defense materials production, nuclear energy research, and radioactive waste management. In may prepared comments today I would like to touch upon four specific subject areas relating to the BWIP program and then I would be happy to answer any questions you might have. The topics I will cover are: (1) historical aspects; (2) site specific technical issues and how they will be addressed during site characterization of the basalt site at Hanford; (3) current project status and; (4) institutional interaction. For clarity, I have attached several charts to my statement

  13. Sardinian basalt. An ancient georesource still en vougue

    Science.gov (United States)

    Careddu, Nicola; Grillo, Silvana Maria

    2017-04-01

    Commercially quarried Sardinian basalt was the result of extensive volcanic activity during the Pliocene and Pleistocene ages, following the opening of the Campidano plain and Tyrrhenian sea rift. Extensive areas of Sardinia have been modelled by large volumes of basalt and andesite rock. An example is provided by the 'Giare' tablelands and other large plateaus located in central Sardinia. Other basalt-rich areas exist in the Island. Sardinia is featured by a vast array of basalt monuments, dating back to the II-I millennium BC, bearing witness to the great workability, durability and resistance to weathering of the rock. The complex of circular defensive towers, known as "Su Nuraxi di Barumini" was included in the World Heritage List by Unesco in 1997. Basalt is currently produced locally to be used for architectural and ornamental purposes. It is obtained by quarrying stone deposits or mining huge boulders which are moved and sawn by means of mechanical machinery. Stone-working is carried out in plants located in various sites of the Island. The paper begins with an historical introduction and then focusses on the current state of the art of Sardinian basalt quarrying, processing and using. An analysis of the basalt market has been carried out.

  14. Building materials. VOC emissions, diffusion behaviour and implications from their use

    International Nuclear Information System (INIS)

    Katsoyiannis, Athanasios; Leva, Paolo; Barrero-Moreno, Josefa; Kotzias, Dimitrios

    2012-01-01

    Five cement- and five lime-based building materials were examined in an environmental chamber for their emissions of Volatile Organic Compounds (VOCs). Typical VOCs were below detection limits, whereas not routinely analysed VOCs, like neopentyl glycol (NPG), dominated the cement-based products emissions, where, after 72 h, it was found to occur, in levels as high as 1400 μg m −3 , accounting for up to 93% of total VOCs. The concentrations of NPG were not considerably changed between the 24 and 72 h of sampling. The permeability of building materials was assessed through experiments with a dual environmental chamber; it was shown that building materials facilitate the diffusion of chemicals through their pores, reaching equilibrium relatively fast (6 h). - Highlights: ► Neopentyl glycol is reported in emissions from building materials for the first time. ► Neopentyl glycol dominates the VOC emissions from cement-based building materials. ► A dual chamber was developed to control diffusion through building materials. ► Building materials facilitate diffusion of indoor air pollutants through their pores. - Neopentyl glycol was detected in high concentrations in emissions from building materials.

  15. TRANSPORT OF INORGANIC COLLOIDS THROUGH NATURAL AQUIFER MATERIAL: IMPLICATIONS FOR CONTAMINANT TRANSPORT

    Science.gov (United States)

    The stability and transport of radiolabeled Fe2O3 particles were studied using laboratory batch and column techniques. Core material collected from a shallow sand and gravel aquifer was used as the immobile column matrix material. Variables in the study incl...

  16. The Thickness and Volume of Young Basalts Within Mare Imbrium

    Science.gov (United States)

    Chen, Yuan; Li, Chunlai; Ren, Xin; Liu, Jianjun; Wu, Yunzhao; Lu, Yu; Cai, Wei; Zhang, Xunyu

    2018-02-01

    Basaltic volcanism is one of the most important geologic processes of the Moon. Research on the thickness and volume of late-stage basalts of Mare Imbrium helps better understand the source of lunar volcanism and eruption styles. Based on whether apparent flow fronts exist or not, the late-stage basalts within Mare Imbrium were divided into two groups, namely, Upper Eratosthenian basalts (UEm) and Lower Eratosthenian basalts (LEm). Employing the topographic profile analysis method for UEm and the crater excavation technique for LEm, we studied the thickness and distribution of Eratosthenian basalts in Mare Imbrium. For the UEm units, their thicknesses were estimated to be 16-34 (±2) m with several layers of individual lava ( 8-13 m) inside. The estimated thickness of LEm units was 14-45(±1) m, with a trend of reducing thickness from north to south. The measured thickness of late-stage basalts around the Chang'E-3 landing site ( 37 ± 1 m) was quite close to the results acquired by the lunar penetrating radar carried on board the Yutu Rover ( 35 m). The total volume of the late-stage basalts in Mare Imbrium was calculated to be 8,671 (±320) km3, which is 4 times lower than that of Schaber's estimation ( 4 × 104 km3). Our results indicate that the actual volume is much lower than previous estimates of the final stage of the late basaltic eruption of Mare Imbrium. Together, the area flux and transport distance of the lava flows gradually decreased with time. These results suggest that late-stage volcanic evolution of the Moon might be revised.

  17. Basaltic volcanic episodes of the Yucca Mountain region

    Energy Technology Data Exchange (ETDEWEB)

    Crowe, B.M.

    1990-03-01

    The purpose of this paper is to summarize briefly the distribution and geologic characteristics of basaltic volcanism in the Yucca Mountain region during the last 10--12 Ma. This interval largely postdates the major period of silicic volcanism and coincides with and postdates the timing of major extensional faulting in the region. Field and geochronologic data for the basaltic rocks define two distinct episodes. The patterns in the volume and spatial distribution of these basaltic volcanic episodes in the central and southern part of the SNVF are used as a basis for forecasting potential future volcanic activity in vicinity of Yucca Mountain. 33 refs., 2 figs.

  18. Manufacture of Green-Composite Sandwich Structures with Basalt Fiber and Bioepoxy Resin

    Directory of Open Access Journals (Sweden)

    J. P. Torres

    2013-01-01

    Full Text Available Nowadays, there is a growing interest for the use and development of materials synthesized from renewable sources in the polymer composites manufacturing industry; this applies for both matrix and reinforcement components. In the present research, a novel basalt fibre reinforced (BFR bioepoxy green composite is proposed as an environmentally friendly alternative to traditional petroleum-derived composites. In addition, this material system was combined with cork as core material for the fabrication of fibre composite sandwich structures. Mechanical properties of both skin and core materials were assessed through flexural and tensile tests. Finite element (FEM simulations for the mechanical stress analysis of the sandwich material were carried out, and a maximum allowable shear stress for material failure under bending loads was established. Permeability measurements of the basalt fabrics were carried out in order to perform numerical simulations of liquid composite moulding (LCM processes on the PAM-RTM software. The proposed green-composite sandwich material was used for the fabrication of a longboard as a case study for a sports equipment application. Numerical simulations of the mould filling stage allowed the determination of an optimal mould filling strategy. Finally, the load-bearing capacity of the board was studied by means of FEM simulations, and the presented design proved to be acceptable for service.

  19. Raising of geo ecological safety of engineering collectors: the new method of assessment of water tightness of reinforced concrete blocks with basalt plastic lining

    Directory of Open Access Journals (Sweden)

    Lyapidevskaya Olga

    2017-01-01

    Full Text Available This work presents analytics ways to estimation and assessment of water tightness of reinforced concrete blocks with basalt plastic lining for increasing geo ecological safety of engineering collectors. It is proved the advisability of application basalt plastic lining instead secondary protection of concrete with hydraulic seal. The results of estimation filtration coefficient and assessment of water tightness of basalt plastic lining of engineering collectors are represented. It is carried out comparative analysis of filtration coefficient and water tightness data of basalt plastic lining and secondary protection. The geo ecological effect is proved at the expense of application of new materials and reducing breakdown events with collectors that may lead pollution of ground and subsoil water with sewage.

  20. Spreading and collapse of big basaltic volcanoes

    Science.gov (United States)

    Puglisi, Giuseppe; Bonforte, Alessandro; Guglielmino, Francesco; Peltier, Aline; Poland, Michael

    2016-04-01

    Among the different types of volcanoes, basaltic ones usually form the most voluminous edifices. Because volcanoes are growing on a pre-existing landscape, the geologic and structural framework of the basement (and earlier volcanic landforms) influences the stress regime, seismicity, and volcanic activity. Conversely, the masses of these volcanoes introduce a morphological anomaly that affects neighboring areas. Growth of a volcano disturbs the tectonic framework of the region, clamps and unclamps existing faults (some of which may be reactivated by the new stress field), and deforms the substratum. A volcano's weight on its basement can trigger edifice spreading and collapse that can affect populated areas even at significant distance. Volcano instability can also be driven by slow tectonic deformation and magmatic intrusion. The manifestations of instability span a range of temporal and spatial scales, ranging from slow creep on individual faults to large earthquakes affecting a broad area. In the frame of MED-SVU project, our work aims to investigate the relation between basement setting and volcanic activity and stability at three Supersite volcanoes: Etna (Sicily, Italy), Kilauea (Island of Hawaii, USA) and Piton de la Fournaise (La Reunion Island, France). These volcanoes host frequent eruptive activity (effusive and explosive) and share common features indicating lateral spreading and collapse, yet they are characterized by different morphologies, dimensions, and tectonic frameworks. For instance, the basaltic ocean island volcanoes of Kilauea and Piton de la Fournaise are near the active ends of long hotspot chains while Mt. Etna has developed at junction along a convergent margin between the African and Eurasian plates and a passive margin separating the oceanic Ionian crust from the African continental crust. Magma supply and plate velocity also differ in the three settings, as to the sizes of the edifices and the extents of their rift zones. These

  1. Chemical implications for the presence of introduced materials in the post-emplacement environment

    International Nuclear Information System (INIS)

    Meike, A.

    1993-11-01

    This paper addresses our ability to predict the chemical consequences of the presence of introduced materials, many of them man-made, in a radioactive waste repository. The chemical modeling ability required to describe this environment over a 10,000 year period is unique and unprecedented. It requires knowledge of parameters that have never been measured, many of them with respect to introduced materials. This paper discusses considerations that are required to establish the potential significance of introduced materials, especially those that could compromise the lifetime of the waste packages or affect the transport of radionuclides from breached containers. The paper presents issues related to the stability of individual compounds, the potential alteration of predicted natural chemical reactions, the potential moderation of those effects by natural zeolites, and the potential for interactions at elevated temperatures between rock, water, water vapor, radiation, waste package, and introduced materials

  2. Femtosecond Laser Irradiation of Plasmonic Nanoparticles in Polymer Matrix: Implications for Photothermal and Photochemical Material Alteration

    Directory of Open Access Journals (Sweden)

    Anton A. Smirnov

    2014-11-01

    Full Text Available We analyze the opportunities provided by the plasmonic nanoparticles inserted into the bulk of a transparent medium to modify the material by laser light irradiation. This study is provoked by the advent of photo-induced nano-composites consisting of a typical polymer matrix and metal nanoparticles located in the light-irradiated domains of the initially homogeneous material. The subsequent irradiation of these domains by femtosecond laser pulses promotes a further alteration of the material properties. We separately consider two different mechanisms of material alteration. First, we analyze a photochemical reaction initiated by the two-photon absorption of light near the plasmonic nanoparticle within the matrix. We show that the spatial distribution of the products of such a reaction changes the symmetry of the material, resulting in the appearance of anisotropy in the initially isotropic material or even in the loss of the center of symmetry. Second, we analyze the efficiency of a thermally-activated chemical reaction at the surface of a plasmonic particle and the distribution of the product of such a reaction just near the metal nanoparticle irradiated by an ultrashort laser pulse.

  3. Hafnium isotope variations in oceanic basalts

    Science.gov (United States)

    Patchett, P. J.; Tatsumoto, M.

    1980-01-01

    Hafnium isotope ratios generated by the beta(-) decay of Lu-176 are investigated in volcanic rocks derived from the suboceanic mantle. Hf-176/Hf-177 and Lu/Hf ratios were determined to precisions of 0.01-0.04% and 0.5%, respectively, by routine, low-blank chemistry. The Hf-176/Hf-177 ratio is found to be positively correlated with the Nd-143/Nd-144 ratio and negatively correlated with the Sr-87/Sr-86 and Pb-206/Pb-204 ratios, and to increase southwards along the Iceland-Reykjanes ridge traverse. An approximate bulk earth Hf-176/Hf-177 ratio of 0.28295 is inferred from the bulk earth Nd-143/Nd-144 ratio, which requires a bulk earth Lu/Hf ratio of 0.25, similar to the Juvinas eucrite. Midocean ridge basalts are shown to account for 60% of the range of Hf isotope ratios, and it is suggested that Lu-Hf fractionation is decoupled from Sm-Nd and Rb-Sr fractionation in very trace-element-depleted source regions as a result of partial melting.

  4. Basalt FRP Spike Repairing of Wood Beams

    Directory of Open Access Journals (Sweden)

    Luca Righetti

    2015-08-01

    Full Text Available This article describes aspects within an experimental program aimed at improving the structural performance of cracked solid fir-wood beams repaired with Basalt Fiber Reinforced Polymer (BFRP spikes. Fir wood is characterized by its low density, low compression strength, and high level of defects, and it is likely to distort when dried and tends to fail under tension due to the presence of cracks, knots, or grain deviation. The proposed repair technique consists of the insertion of BFRP spikes into timber beams to restore the continuity of cracked sections. The experimental efforts deal with the evaluation of the bending strength and deformation properties of 24 timber beams. An artificially simulated cracking was produced by cutting the wood beams in half or notching. The obtained results for the repaired beams were compared with those of solid undamaged and damaged beams, and increases of beam capacity, bending strength and of modulus of elasticity, and analysis of failure modes was discussed. For notched beams, the application of the BFRP spikes was able to restore the original bending capacity of undamaged beams, while only a small part of the original capacity was recovered for beams that were cut in half.

  5. Borehole plugging of man-made accesses to a basalt repository: a preliminary study

    International Nuclear Information System (INIS)

    Taylor, C.L.; Anttonen, G.J.; O'Rourke, J.E.; Niccum, M.R.

    1979-09-01

    This report describes the status of work currently in progress for the Basalt Borehole Plugging Program (BBPP). The primary objectives of the BBPP outlined in this report have been met during this first phase of work. These objectives included: (1) the preparation of a preliminary list of candidate plug materials; (2) a description of available machinery capable of placing candidate plug materials; and (3) the development of physical and geochemical testing programs to help evaluate the chemical stability and physical properties of candidate plug materials. The most significant finding from work to date is that given reasonable regulatory criteria, nothing has been identified which would prevent design of a plug system to seal manmade openings leading to a nuclear waste repository in Columbia River basalt for significantly long periods of time (on the order of thousands of years). Work accomplished to date indicates that this plug system can be designed using both natural and manufactured materials and can be emplaced with existing placement machinery and modifications of that machinery. The objectives of Task II are to conduct laboratory tests to evaluate the suitability of preferred candidate materials for plugging boreholes in the proposed repository, select plug system(s), initiate preconceptual machinery design for the placement of materials in plug system(s), and prepare a preliminary Task II report. As with Task I project organization, Task II is divided into subtasks that are identified by written subtask work summaries

  6. Laser Ar-39-Ar-40 study of Apollo 17 basalts

    Science.gov (United States)

    Schaeffer, O. A.; Mueller, H. W.; Grove, T. L.

    1977-01-01

    Three Apollo 17 basalts were studied by the laser Ar-39-Ar-40 method. The 70215 basalt has a normal well-behaved Ar-39-Ar-40 release pattern; the 70017 basalt has a disturbed release pattern which indicates a limited intermediate maximum age followed by a broad low-age region; and the 75035 basalt has a pattern initially similar to 70017 that is followed by a high-temperature maximum age. The laser study shows that all mineral systems in 70215 have small and uniform temperature losses, while the laser-determined ages for 70017 and 75035 are, apparently, primarily controlled by the minerals containing mesostasis inclusions. It is possible that the drop in ages observed by the conventional Ar-39-Ar-40 method was due not only to recoil of Ar-39 during neutron irradiation but also to gas loss from some minerals. It is suggested that the plagioclases are the best minerals to use for a reliable age.

  7. Materials

    CSIR Research Space (South Africa)

    Van Wyk, Llewellyn V

    2009-02-01

    Full Text Available community. The construction industry is a significantly consumer of materials, using 50 per cent of all products produced globally. Building materials is any material which is used for a construction purpose. Many of these materials are sources from natural...

  8. Underground autocatalytic-criticality potential and its implications to weapons fissile- material disposition

    International Nuclear Information System (INIS)

    Choi, J.-S.

    1998-01-01

    Several options for weapons fissile-material disposition, such as once-through mixed- oxide (MOX) fuel in reactors or immobilisation in waste glass, would result in end products requiring geologic disposal. The criticality potential of the fissile end products containing U-235 and Pu-239 and the associated consequences in a geologic setting are important considerations for the final disposal of these materials. The possibility of underground criticality, and especially autocatalytic criticality, is affected by (1) groundwater leaking into a failed waste container, (2) preferential leaching of neutron absorbers or of fissile material from a failed container, and (3) preferential deposition of fissile material in the surrounding rock. Bowman and Venneri have pointed out that fissile material mixed with varying compositions of water and silica can undergo a nuclear chain reaction. Some configurations can become autocatalytically supercritical resulting in considerable energy release, terminated finally by disassembly. Some reviews rejected the Bowman and Venneri warning as implausible because of low probabilities of scenarios that could lead to such configurations. Sanchez et al. reported possible supercritical conditions in systems of Pu-SiO 2 -H 2 O and Pu-tuff-H 2 O but concluded that the probability of forming such combinations is extremely low. Kastenberg et al. studied the potential for autocatalytic criticality of plutonium or highly enriched uranium in the proposed Yucca Mountain geologic repository. They concluded that plutonium or uranium could, theoretically, become supercritical, but that such criticality is unlikely given the hydrology, geology and geochemistry of the Yucca Mountain site. These studies are not definitive. The possibility of criticality exists. Detailed mechanisms have not been sufficiently studied for clear conclusions on the probabilities of occurrence. More technical analysis is needed to understand the potential for underground

  9. Zirconium and hafnium abundances in some lunar materials and implications of their ratios

    Science.gov (United States)

    Chyi, L. L.; Ehmann, W. D.

    1973-01-01

    A new rapid and precise analytical procedure for Zr and Hf has been applied to the study of lunar materials. The results indicate that the Zr/Hf ratios in lunar materials vary in a narrow range from 36.6 to 51.3 while their respective contents vary by a factor of 40. There is a strong Zr, Hf, and major element correlation. This correlation and the Zr and Hf systematics suggest that lunar materials fall into two groups. One group characterized by high Zr and Hf contents and higher Zr/Hf ratios corresponds to materials with a high KREEP content; the other characterized by low Zr and Hf contents and lower Zr/Hf ratios corresponds to materials with high Ti, Fe, Mn, and Mg contents. We believe that the modest Zr and Hf fractionation we observe is related to the extent of stabilization of the metals in the early titanium minerals and a charge disparity under extremely reduced conditions in which Zr exists as 3+, while Hf remains as 4+.

  10. Deuteron and neutron induced activation in the Eveda accelerator materials: implications for the accelerator maintenance

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, M.; Sanz, J.; Garcia, N.; Cabellos, O. [Madrid Univ. Politecnica, C/ Jose Gutierrez Abascal, lnstituto de Fusion Nuclear (Spain); Sauvan, R. [Universidad Nacional de Educacion a Distancia (UNED), Madrid (Spain); Moreno, C.; Sedano, L.A. [CIEMAT-Centro de Investigaciones Energeticas Medioambientales y Tecnologicas, Association Euratom-CIEMAT, Madrid (Spain)

    2007-07-01

    Full text of publication follows: The IFMIF (International Fusion Materials Irradiation Facility) is an accelerator-based DLi neutron source designed to test fusion reactor candidate materials for high fluence neutrons. Before deciding IFMIF construction, an engineering design and associated experimental data acquisition, defined as EVEDA, has been proposed. Along the EVEDA accelerator, deuteron beam losses collide with the accelerator materials, producing activation and consequent radiations responsible of dose. Calculation of the dose rates in the EVEDA accelerator room is necessary in order to analyze the feasibility for manual maintenance. Dose rates due to the activation produced by the deuteron beam losses interaction with the accelerator materials, will be calculated with the ACAB activation code, using EAF2007 library for deuteron activation cross-sections. Also, dose rates from the activation induced by the neutron source produced by the interaction of deuteron beam losses with the accelerator materials and the deuterium implanted in the structural lattice, will be calculated with the SRIM2006, TMAP7, DROSG2000/NEUYIE, MCNPX and ACAB codes. All calculations will be done for the EVEDA accelerator with the room temperature DTL structure, which is based on copper cavities for the DTL. Some calculations will be done for the superconducting DTL structure, based on niobium cavities for the DTL working at cryogenic temperature. Final analysis will show the dominant mechanisms and major radionuclides contributing to the surface dose rates. (authors)

  11. Chemical magnetization when determining Thellier paleointensity experiments in oceanic basalts

    Science.gov (United States)

    Tselebrovskiy, Alexey; Maksimochkin, Valery

    2017-04-01

    The natural remanent magnetization (NRM) of oceanic basalts selected in the rift zones of the Mid-Atlantic Ridge (MAR) and the Red Sea has been explored. Laboratory simulation shows that the thermoremanent magnetization and chemical remanent magnetization (CRM) in oceanic basalts may be separated by using Tellier-Coe experiment. It was found that the rate of CRM destruction is about four times lower than the rate of the partial thermoremanent magnetization formation in Thellier cycles. The blocking temperatures spectrum of chemical component shifted toward higher temperatures in comparison with the spectrum of primary thermoremanent magnetization. It was revealed that the contribution of the chemical components in the NRM increases with the age of oceanic basalts determined with the analysis of the anomalous geomagnetic field (AGF) and spreading theory. CRM is less than 10% at the basalts aged 0.2 million years, less than 50% at basalts aged 0.35 million years, from 60 to 80% at basalts aged 1 million years [1]. Geomagnetic field paleointensity (Hpl) has been determined through the remanent magnetization of basalt samples of different ages related to Brunhes, Matuyama and Gauss periods of the geomagnetic field polarity. The value of the Hpl determined by basalts of the southern segment of MAR is ranged from 17.5 to 42.5 A/m, by the Reykjanes Ridge basalts — from 20.3 to 44 A/m, by the Bouvet Ridge basalts — from 21.7 to 34.1 A/m. VADM values calculated from these data are in good agreement with the international paleointensity database [2] and PISO-1500 model [3]. Literature 1. Maksimochkin V., Tselebrovskiy A., (2015) The influence of the chemical magnetization of oceanic basalts on determining the geomagnetic field paleointensity by the thellier method, moscow university physics bulletin, 70(6):566-576, 2. Perrin, M., E. Schnepp, and V. Shcherbakov (1998), Update of the paleointensity database, Eos Trans. AGU, 79, 198. 3. Channell JET, Xuan C, Hodell DA (2009

  12. Long-term alteration of basaltic glass: Mechanisms and rates

    Science.gov (United States)

    Parruzot, Benjamin; Jollivet, Patrick; Rébiscoul, Diane; Gin, Stéphane

    2015-04-01

    The long-term behavior study of archaeological artifacts and natural minerals and glasses revealed discrepancies between laboratory and field data. For a better understanding of the cause of these discrepancies and to reinforce the use of basaltic glass as an analog for nuclear waste glasses, this study focuses on the determination of alteration rates and processes of synthetic basaltic glass in residual rate regime. Laboratory batch experiments were performed at high surface-to-volume ratios at 90 and 30 °C for more than 1000 days. In all the experiments, the residual rate regime was reached after about 6 months. The residual alteration rates at 30 and 90 °C were 4.0 ± 1.0 × 10-6 and 9.5 ± 3.2 × 10-6 g·m-2·d-1, respectively. At 90 °C, this residual alteration rate is five orders of magnitude lower than the forward alteration rate (0.8 g·m-2·d-1). Altered powders and monoliths were characterized by Transmission Electron Microscopy and Time-of-Flight Secondary Ion Mass Spectrometry. From glass core to solution, the altered materials are structured as follows: pristine glass, gel (corresponding to the palagonitic layer of natural glasses) and intergranular clays. To assess the passivating properties of this alteration film, we used solid characterization, an isotopically-tagged post-leaching experiment and the measurement of mobile species diffusion coefficients through the alteration film at different stages of reaction using various techniques (solution analysis and X-ray Reflectometry). These characterizations showed that the alteration film formed during residual rate alteration is passivating even without clogged porosity within the gel. Diffusion coefficients of water and alkali metals - respectively diffusing to and from the pristine glass - through the alteration film dropped from 10-20 to 10-19 m2·s-1 during the first alteration stages to 10-25 m2·s-1 in residual rate regime.

  13. Geochemistry of the Potassic Basalts from the Bufumbira Volcanic ...

    African Journals Online (AJOL)

    The various basalts are low in SiO2 wt %, Al2O3 wt % and Na2O wt % but high in MgO wt %, TiO2 wt %, CaO wt %, K2O wt % with K2O/Na2O = 1.08 to 2.07. These are potassic belonging to the kamafugite series. Plots discriminate two geochemical trends corresponding to the picritic and clinopyroxene rich basalts.

  14. Radiolytic hydrogen production in the subseafloor basaltic aquifer

    Directory of Open Access Journals (Sweden)

    Mary E Dzaugis

    2016-02-01

    Full Text Available Hydrogen (H2 is produced in geological settings by dissociation of water due to radiation from radioactive decay of naturally occurring uranium (238U, 235U, thorium (232Th and potassium (40K. To quantify the potential significance of radiolytic H2 as an electron donor for microbes within the South Pacific subseafloor basaltic aquifer, we use radionuclide concentrations of 43 basalt samples from IODP Expedition 329 to calculate radiolytic H2 production rates in basement fractures. The samples are from three sites with very different basement ages and a wide range of alteration types. U, Th and K concentrations vary by up to an order of magnitude from sample to sample at each site. Comparison of our samples to each other and to the results of previous studies of unaltered East Pacific Rise basalt suggests that significant variations in radionuclide concentrations are due to differences in initial (unaltered basalt concentrations (which can vary between eruptive events and post-emplacement alteration. In our samples, there is no clear relationship between alteration type and calculated radiolytic yields. Local maxima in U, Th, and K produce hotspots of H2 production, causing calculated radiolytic rates to differ by up to a factor of 80 from sample to sample. Fracture width also greatly influences H2 production, where microfractures are hotspots for radiolytic H2 production. For example, H2 production rates normalized to water volume are 190 times higher in 1 μm wide fractures than in fractures that are 10 cm wide. To assess the importance of water radiolysis for microbial communities in subseafloor basaltic aquifers, we compare electron transfer rates from radiolysis to rates from iron oxidation in subseafloor basalt. Radiolysis appears likely to be a more important electron donor source than iron oxidation in old (>10 Ma basement basalt. Radiolytic H2 production in the volume of water adjacent to a square cm of the most radioactive SPG basalt may

  15. PREDICTION OF BASALT FIBER REINFORCED CONCRETE PAVEMENT BENDING STRENGTH VALUES

    OpenAIRE

    Hidayet BAYRAKTAR; Ayhan SAMANDAR; Suat SARIDEMİR

    2017-01-01

    This paper proposes the potential of artificial neural network (ANN) system for estimating the bending strength values of the basalt fiber reinforced concrete pavements. Three main influential parameters; namely basalt fiber ratio, density and slump value of the fresh concrete were selected as input data. The model was trained, tested using 400 data sets which were the results of on-site experiment tests. ANN system results were also compared with the experimental test results. The research r...

  16. Endocrine disruptors and dental materials: health implications associated with their use in Brazil

    Directory of Open Access Journals (Sweden)

    Coelho Antonio Jorge Molinário

    2002-01-01

    Full Text Available This study analyzes international historical trends in the use of different types of materials in dental practice. The author describes the chemical properties of their ingredients and the potential and observed adverse effects in patients and dental technicians resulting from clinical or occupational exposure to various metals like beryllium, used to produce metal alloys. The growing use of various products (resin cements, ionomer cements, aesthetic restorative materials, resins, endodontal cements, and others based on the compound bisphenol-A, whose chemical structure is similar to that of estrogen. Considering the demographic and contemporary work force characteristics of those involved in dental practice in the Brazil, the study highlights the possible effect of the use of these materials in both male and female patients and all age strata, as well as in health professionals with occupational exposure to products containing bisphenol-A.

  17. Endocrine disruptors and dental materials: health implications associated with their use in Brazil

    Directory of Open Access Journals (Sweden)

    Antonio Jorge Molinário Coelho

    2002-04-01

    Full Text Available This study analyzes international historical trends in the use of different types of materials in dental practice. The author describes the chemical properties of their ingredients and the potential and observed adverse effects in patients and dental technicians resulting from clinical or occupational exposure to various metals like beryllium, used to produce metal alloys. The growing use of various products (resin cements, ionomer cements, aesthetic restorative materials, resins, endodontal cements, and others based on the compound bisphenol-A, whose chemical structure is similar to that of estrogen. Considering the demographic and contemporary work force characteristics of those involved in dental practice in the Brazil, the study highlights the possible effect of the use of these materials in both male and female patients and all age strata, as well as in health professionals with occupational exposure to products containing bisphenol-A.

  18. The geological nature of dark material on Vesta and implications for the subsurface structure

    OpenAIRE

    Jaumann, R.; Nass, Andrea; Otto, K.; Krohn, K.; Stephan, K.; McCord, T.B.; Williams, D.A.; Raymond, C.A.; Blewett, D.T.; Hiesinger, H.; Yingst, R.A.; De Sanctis, M.C.; Palomba, E.; Roatsch, Thomas; Matz, K.-D.

    2014-01-01

    Abstract Deposits of dark material appear on Vesta’s surface as features of relatively low-albedo in the visible wavelength range of Dawn’s camera and spectrometer. Mixed with the regolith and partially excavated by younger impacts, the material is exposed as individual layered outcrops in crater walls or ejecta patches, having been uncovered and broken up by the impact. Dark fans on crater walls and dark deposits on crater floors are the result of gravity-driven mass wasting triggered by ste...

  19. Insulation from basaltic stamp sand. Final technical report

    Energy Technology Data Exchange (ETDEWEB)

    Williams, F. D.

    1981-04-01

    A Midwest Appropriate Technology Grant was awarded to determine the technical and economic feasibility of producing mineral-fiber insulation directly from extensive deposits of basaltic sand produced during former mining and milling operations in the Keweenaw Peninsula region of Michigan's Upper Peninsula. The amounts of local basaltic sands available and representative chemical compositions were determined. The variation of viscosity with temperature and chemical composition was estimated. Samples were melted and either pulled or blown into fiber. In all cases fiber could be made with a reasonable tensile strength to ensure usefulness. It was concluded that it was technically feasible to produce fibers from basaltic stamp sands of the Upper Peninsula of Michigan. A technical feasibility study using published data, a cost and design analysis of a basalt fiber production plant, a market survey of fiber needs, and an economic analysis for investing in a basalt fiber venture was undertaken. These studies concluded that the local production of basaltic insulation was both feasible and economically reasonable. It was suggested that the plant be located in a region of greater population density with lower utility costs. A representative one-third of these studies is included as appendices A, B, C, and D.

  20. Plate tectonics and continental basaltic geochemistry throughout Earth history

    Science.gov (United States)

    Keller, Brenhin; Schoene, Blair

    2018-01-01

    Basaltic magmas constitute the primary mass flux from Earth's mantle to its crust, carrying information about the conditions of mantle melting through which they were generated. As such, changes in the average basaltic geochemistry through time reflect changes in underlying parameters such as mantle potential temperature and the geodynamic setting of mantle melting. However, sampling bias, preservation bias, and geological heterogeneity complicate the calculation of representative average compositions. Here we use weighted bootstrap resampling to minimize sampling bias over the heterogeneous rock record and obtain maximally representative average basaltic compositions through time. Over the approximately 4 Ga of the continental rock record, the average composition of preserved continental basalts has evolved along a generally continuous trajectory, with decreasing compatible element concentrations and increasing incompatible element concentrations, punctuated by a comparatively rapid transition in some variables such as La/Yb ratios and Zr, Nb, and Ti abundances approximately 2.5 Ga ago. Geochemical modeling of mantle melting systematics and trace element partitioning suggests that these observations can be explained by discontinuous changes in the mineralogy of mantle partial melting driven by a gradual decrease in mantle potential temperature, without appealing to any change in tectonic process. This interpretation is supported by the geochemical record of slab fluid input to continental basalts, which indicates no long-term change in the global proportion of arc versus non-arc basaltic magmatism at any time in the preserved rock record.

  1. Carbon Sequestration in Olivine and Basalt Powder Packed Beds.

    Science.gov (United States)

    Xiong, Wei; Wells, Rachel K; Giammar, Daniel E

    2017-02-21

    Fractures and pores in basalt could provide substantial pore volume and surface area of reactive minerals for carbonate mineral formation in geologic carbon sequestration. In many fractures solute transport will be limited to diffusion, and opposing chemical gradients that form as a result of concentration differences can lead to spatial distribution of silicate mineral dissolution and carbonate mineral precipitation. Glass tubes packed with grains of olivine or basalt with different grain sizes and compositions were used to explore the identity and spatial distribution of carbonate minerals that form in dead-end one-dimensional diffusion-limited zones that are connected to a larger reservoir of water in equilibrium with 100 bar CO 2 at 100 °C. Magnesite formed in experiments with olivine, and Mg- and Ca-bearing siderite formed in experiments with flood basalt. The spatial distribution of carbonates varied between powder packed beds with different powder sizes. Packed beds of basalt powder with large specific surface areas sequestered more carbon per unit basalt mass than powder with low surface area. The spatial location and extent of carbonate mineral formation can influence the overall ability of fractured basalt to sequester carbon.

  2. Development and characterization of basalt-glass ceramics for the immobilization of transuranic wastes

    International Nuclear Information System (INIS)

    Lokken, R.O.; Chick, L.A.; Thomas, L.E.

    1982-09-01

    Basalt-based waste forms were developed for the immobilization of transuranic (TRU) contaminated wastes. The specific waste studied is a 3:1 blend of process sludge and incinerator ash. Various amounts of TRU blended waste were melted with Pomona basalt powder. The vitreous products were subjected to a variety of heat treatment conditions to form glass ceramics. The total crystallinity of the glass ceramic, ranging from 20 to 45 wt %, was moderately dependent on composition and heat treatment conditions. Three parent glasses and four glass ceramics with varied composition and heat treatment were produced for detailed phase characterization and leaching. Both parent glasses and glass ceramics were mainly composed of a continuous, glassy matrix phase. This glass matrix entered into solution during leaching in both types of materials. The Fe-Ti rich dispersed glass phase was not significantly degraded by leaching. The glass ceramics, however, exhibited four to ten times less elemental releases during leaching than the parent glasses. The glass ceramic matrix probably contains higher Fe and Na and lower Ca and Mg relative to the parent glass matrix. The crystallization of augite in the glass ceramics is believed to contribute to the improved leach rates. Leach rates of the basalt glass ceramic are compared to those of other TRU nuclear waste forms containing 239 Pu

  3. Microbially mediated alteration of crystalline basalts as identified from analogical reactive percolation experiments

    Science.gov (United States)

    Moore, Rachael; Ménez, Bénédicte; Stéphant, Sylvian; Dupraz, Sébastien; Ranchou-Peyruse, Magali; Ranchou-Peyruse, Anthony; Gérard, Emmanuelle

    2017-04-01

    Alteration in the ocean crust through fluid circulation is an ongoing process affecting the first kilometers and at low temperatures some alteration may be microbially mediated. Hydrothermal activity through the hard rock basement supports diverse microbial communities within the rock by providing nutrient and energy sources. Currently, the impact of basement hosted microbial communities on alteration is poorly understood. In order to identify and quantify the nature of microbially mediated alteration two reactive percolation experiments mimicking circulation of CO2 enriched ground water were performed at 35 °C and 30 bar for 21 days each. The experiments were performed using a crystalline basalt substrate from an earlier drilled deep Icelandic aquifer. One experiment was conducted on sterile rock while the other was conducted with the addition of a microbial inoculate derived from groundwater enrichment cultures obtained from the same aquifer. µCT on the experimental basaltic substrate before and after the reactive percolation experiment along with synchrotron radiation x-ray tomographic microscopy and the mineralogical characterization of resulting material allows for the comparative volumetric quantification of dissolution and precipitation. The unique design of this experiment allows for the identification of alteration which occurs solely abiotically and of microbially mediated alteration. Experimental results are compared to natural basaltic cores from Iceland retrieved following a large field CO2 injection experiment that stimulated microbial activity at depth.

  4. Site selection report basalt waste isolation program near-surface test facility

    International Nuclear Information System (INIS)

    Sharpe, S.D.

    1978-01-01

    A site selection committee was established to review the information gathered on potential sites and to select a site for the Near-Surface Test Facility Phase I. A decision was made to use a site on the north face of Gable Mountain located on the Hanford Site. This site provided convenient access to the Pomona Basalt Flow. This flow was selected for use at this site because it exhibited the characteristics established in the primary criteria. These criteria were: the flows thickness; its dryness; its nearness to the surface; and, its similarities to basalt units which are candidates for the repository. After the selection of the Near-Surface Test Facility Phase I Site, the need arose for an additional facility to demonstrate safe handling, storage techniques, and the physical effects of radioactive materials on an in situ basalt formation. The committee reviewed the sites selected for Phase I and chose the same site for locating Phase II of the Near-Surface Test Facility

  5. (TMTSF)2X materials and structural implications for low-dimensional polymeric and disordered molecular semiconductors

    DEFF Research Database (Denmark)

    Bechgaard, Klaus; Nielsen, Martin Meedom; Krebs, Frederik C

    2000-01-01

    The structural characteristics and the relation to the electronic properties of three types of molecular materials are discussed. In TMTSF2X salts a triclinic unit cell it suggested to be important in avoiding a 2k(F) Peierls distortion. In polythiophenes appropriate ordering of microcrystallites...

  6. Mechanical characterization of raw material quality and its implication for Early Upper Palaeolithic Moravia

    Czech Academy of Sciences Publication Activity Database

    Monik, M.; Hadraba, Hynek

    2016-01-01

    Roč. 425, DEC (2016), s. 425-436 ISSN 1040-6182 R&D Projects: GA MŠk(CZ) ED1.1.00/02.0068 Institutional support: RVO:68081723 Keywords : Charpy impact test * Microhardness * Early Upper Palaeolithic * Moravia * Lithics Subject RIV: JH - Ceramics, Fire-Resistant Materials and Glass Impact factor: 2.199, year: 2016

  7. Smart Materials Meet Multifunctional Biomedical Devices: Current and Prospective Implications for Nanomedicine

    Directory of Open Access Journals (Sweden)

    Giada Graziana Genchi

    2017-12-01

    Full Text Available With the increasing advances in the fabrication and in monitoring approaches of nanotechnology devices, novel materials are being synthesized and tested for the interaction with biological environments. Among them, smart materials in particular provide versatile and dynamically tunable platforms for the investigation and manipulation of several biological activities with very low invasiveness in hardly accessible anatomical districts. In the following, we will briefly recall recent examples of nanotechnology-based materials that can be remotely activated and controlled through different sources of energy, such as electromagnetic fields or ultrasounds, for their relevance to both basic science investigations and translational nanomedicine. Moreover, we will introduce some examples of hybrid materials showing mutually beneficial components for the development of multifunctional devices, able to simultaneously perform duties like imaging, tissue targeting, drug delivery, and redox state control. Finally, we will highlight challenging perspectives for the development of theranostic agents (merging diagnostic and therapeutic functionalities, underlining open questions for these smart nanotechnology-based devices to be made readily available to the patients in need.

  8. Hyper-localized carbon mineralization in diffusion-limited basalt fractures

    Science.gov (United States)

    Menefee, A. H.; Giammar, D.; Ellis, B. R.

    2017-12-01

    clays filling the advective path, no permeability changes were measured. Our coupled experiment-modeling approach further elucidates the geochemical conditions controlling carbonation reactions and extends unique microstructural observations to implications for long-term CO2 mineralization in basalt reservoirs.

  9. Icelandic basaltic geothermal field: A natural analog for nuclear waste isolation in basalt

    International Nuclear Information System (INIS)

    Ulmer, G.C.; Grandstaff, D.E.

    1984-01-01

    Analog studies of Icelandic geothermal fields have shown that the design of nuclear waste repositories in basalt can benefit by comparison to the data base already available from the development of these geothermal fields. A high degree of similarity exists between these two systems: their petrology, groundwater geochemistry, mineral solubilities, hydrologic parameters, temperature ranges, water-rock redox equilibria, hydrothermal pH values, and secondary mineralogies all show considerable overlap in the range of values. The experimentally-simulated hydrothermal studies of the basaltic nuclear waste repository rocks have, at this time, produced a data base that receives a strong confirmation from the Icelandic analog. Furthermore, the Icelandic analog should eventually be employed to extrapolate into higher and lower temperatures, into longer time-base chemical comparisons, and into more realistic mineral deposition studies, than have been possible in the laboratory evaluations of the nuclear waste repository designs. This eventual use of the Icelandic analog will require cooperative work with the Icelandic Geological Survey. 46 refs., 4 figs., 2 tabs

  10. Basalt Waste Isolation Project Reclamation Support Project:

    Energy Technology Data Exchange (ETDEWEB)

    Brandt, C.A.; Rickard, W.H. Jr.; Cadoret, N.A.

    1992-06-01

    The Basalt Waste Isolation Project (BWIP) Reclamation Support Project began in the spring of 1988 by categorizing sites distributed during operations of the BWIP into those requiring revegetation and those to be abandoned or transferred to other programs. The Pacific Northwest Laboratory's role in this project was to develop plans for reestablishing native vegetation on the first category of sites, to monitor the implementation of these plans, to evaluate the effectiveness of these efforts, and to identify remediation methods where necessary. The Reclamation Support Project focused on three major areas: geologic hydrologic boreholes, the Exploratory Shaft Facility (ESF), and the Near-Surface Test Facility (NSTF). A number of BWIP reclamation sites seeded between 1989 and 1990 were found to be far below reclamation objectives. These sites were remediated in 1991 using various seedbed treatments designed to rectify problems with water-holding capacity, herbicide activity, surficial crust formation, and nutrient imbalances. Remediation was conducted during November and early December 1991. Sites were examined on a monthly basis thereafter to evaluate plant growth responses to these treatments. At all remediation sites early plant growth responses to these treatments. At all remediation sites, early plant growth far exceeded any previously obtained using other methods and seedbed treatments. Seeded plants did best where amendments consisted of soil-plus-compost or fertilizer-only. Vegetation growth on Gable Mountain was less than that found on other areas nearby, but this difference is attributed primarily to the site's altitude and north-facing orientation.

  11. Mid-IR Reflectance (DRIFT) Spectral Variations in Basaltic Mineralogy with Direction of Impact at Lonar Crater, India

    Science.gov (United States)

    Basavaiah, N.; Chavan, R. S.; Arif, M.

    2012-12-01

    Identification of spectral changes with the direction of impact has important implications for understanding the impact cratering phenomenon occurring on both terrestrial and extraterrestrial planets and also for geology of the crater. Fortuitously, Lonar Impact Crater (India) is the only well-preserved terrestrial simple crater excavated on Deccan basalts and serves as an excellent analogue to craters on Mars and Moon. An ~570 ka old Lonar crater was suggested to be formed by an oblique impact of a chondritic impactor that struck the pre-impact target from the east into a sequence of six basaltic Deccan flows and created a 1.88 km diameter crater with two layers of ejecta blanket. Here we report preliminary laboratory studies of spectral results on fine-grained rock powers (IR (4000-400 cm-1) Diffuse Reflectance Infrared Fourier Transform (DRIFT) spectroscopy. The basalts were collected from two profiles in the east and south sections of the crater wall and the upper most crater rim, which later subdivided into sector-wise samples to carry out a systematic study of spectral properties of Lonar basalts, together with impact related samples of breccias and impact melts. For the first time, data of the shock metamorphism of Lonar basalt is examined using DRIFT spectroscopy. Infrared spectra of rock powders of relatively unshocked and shocked basalts are obtained to document the mineralogical variations and the distribution of primary (e.g. Plagioclase Feldspar, Pyroxene), and secondary Phyllosilicate minerals (e.g. Illite, Smectite, Montmorillonite, Saponite, Serpentine) with direction of impact. The spectral data between pre-impact unshocked and post-impact shocked basalts are interpreted to reflect the effect of shock pressure and alteration that rock have undergone. On western crater rim sector, typical silicate spectral features in 900-1200 cm-1 which attributed to Si-O stretching, are observed to change slightly in the width and shift in position as a result of

  12. PROPERTIES AND MANAGEMENT IMPLICATIONS OF SOILS FORMED FROM VOLCANIC MATERIALS IN LEMBANG AREA, WEST JAVA

    OpenAIRE

    Edi Yatno; Siti Zauyah

    2016-01-01

    Soils formed from volcanic materials have a high potential for agricultural development, especially for horticultural crops, tea, and pine trees. Data on the characteristics of these soils are important for the management planning. Six representative soil profiles developed on andesitic volcanic ash and tuff in Lembang area, West Java were studied to determine the soil physical, chemical, and mineralogical properties, to study the relationship between the soil properties, and to classify the ...

  13. Properties and Management Implications of Soils Formed From Volcanic Materials in Lembang Area, West Java

    OpenAIRE

    Yatno, Edi; Zauyah, Siti

    2008-01-01

    Soils formed from volcanic materials have a high potential for agricultural development, especially for horticultural crops, tea, and pine trees. Data on the characteristics of these soils are important for the management planning. Six representative soil profiles developed on andesitic volcanic ash and tuff in Lembang area, West Java were studied to determine the soil physical, chemical, and mineralogical properties, to study the relationship between the soil properties, and to classify the ...

  14. Radiation response of industrial materials: Dose-rate and morphology implications

    Science.gov (United States)

    Berejka, Anthony J.

    2007-08-01

    Industrial uses of ionizing radiation mostly rely upon high current, high dose-rate (100 kGy/s) electron beam (EB) accelerators. To a lesser extent, industry uses low dose-rate (2.8 × 10-3 kGy/s) radioactive Cobalt-60 as a gamma source, generally for some rather specific purposes, as medical device sterilization and the treatment of food and foodstuffs. There are nearly nine times as many (∼1400) high current EB units in commercial operation than gamma sources (∼160). However, gamma sources can be easily scaled-down so that much research on materials effects is conducted using gamma radiation. Likewise, laboratories are more likely to have very low beam current and consequently low dose-rate accelerators such as Van de Graaff generators and linear accelerators. With the advent of very high current EB accelerators, X-ray processing has become an industrially viable option. With X-rays from high power sources, dose-rates can be modulated based upon accelerator power and the attenuation of the X-ray by the distance of the material from the X-ray target. Dose and dose-rate dependence has been found to be of consequence in several commercial applications which can employ the use of ionizing radiation. The combination of dose and dose-rate dependence of the polymerization and crosslinking of wood impregnants and of fiber composite matrix materials can yield more economically viable results which have promising commercial potential. Monomer and oligomer structure also play an important role in attaining these desirable results. The influence of morphology is shown on the radiation response of olefin polymers, such as ethylene, propylene and isobutylene polymers and their copolymers. Both controlled morphology and controlled dose-rate have commercial consequences. These are also impacted both by the adroit selection of materials and through the possible use of X-ray processing.

  15. Neutron induced activation in the EVEDA accelerator materials: Implications for the accelerator maintenance

    Energy Technology Data Exchange (ETDEWEB)

    Sanz, J. [Department of Power Engineering, Universidad Nacional de Educacion a Distancia (UNED), C/Juan del Rosal 12, 28040 Madrid (Spain); Institute of Nuclear Fusion, UPM, 28006 Madrid (Spain)], E-mail: jsanz@ind.uned.es; Garcia, M.; Sauvan, P.; Lopez, D. [Department of Power Engineering, Universidad Nacional de Educacion a Distancia (UNED), C/Juan del Rosal 12, 28040 Madrid (Spain); Institute of Nuclear Fusion, UPM, 28006 Madrid (Spain); Moreno, C.; Ibarra, A.; Sedano, L. [CIEMAT, 28040 Madrid (Spain)

    2009-04-30

    The Engineering Validation and Engineering Design Activities (EVEDA) phase of the International Fusion Materials Irradiation Facility project should result in an accelerator prototype for which the analysis of the dose rates evolution during the beam-off phase is a necessary task for radioprotection and maintenance feasibility purposes. Important aspects of the computational methodology to address this problem are discussed, and dose rates for workers inside the accelerator vault are assessed and found to be not negligible.

  16. Neutron induced activation in the EVEDA accelerator materials: Implications for the accelerator maintenance

    International Nuclear Information System (INIS)

    Sanz, J.; Garcia, M.; Sauvan, P.; Lopez, D.; Moreno, C.; Ibarra, A.; Sedano, L.

    2009-01-01

    The Engineering Validation and Engineering Design Activities (EVEDA) phase of the International Fusion Materials Irradiation Facility project should result in an accelerator prototype for which the analysis of the dose rates evolution during the beam-off phase is a necessary task for radioprotection and maintenance feasibility purposes. Important aspects of the computational methodology to address this problem are discussed, and dose rates for workers inside the accelerator vault are assessed and found to be not negligible.

  17. Monte Carlo simulation of electron thermalization in scintillator materials: Implications for scintillator nonproportionality

    Science.gov (United States)

    Prange, Micah P.; Xie, YuLong; Campbell, Luke W.; Gao, Fei; Kerisit, Sebastien

    2017-12-01

    The lack of reliable quantitative estimates of the length and time scales associated with hot electron thermalization after a gamma-ray induced energy cascade obscures the interplay of various microscopic processes controlling scintillator performance and hampers the search for improved detector materials. We apply a detailed microscopic kinetic Monte Carlo model of the creation and subsequent thermalization of hot electrons produced by gamma irradiation of six important scintillating crystals to determine the spatial extent of the cloud of excitations produced by gamma rays and the time required for the cloud to thermalize with the host lattice. The main ingredients of the model are ensembles of microscopic track structures produced upon gamma excitation (including the energy distribution of the excited carriers), numerical estimates of electron-phonon scattering rates, and a calculated particle dispersion to relate the speed and energy of excited carriers. All these ingredients are based on first-principles density functional theory calculations of the electronic and phonon band structures of the materials. The details of the Monte Carlo model are presented along with the results for thermalization time and distance distributions. These results are discussed in light of previous work. It is found that among the studied materials, calculated thermalization distances are positively correlated with measured nonproportionality. In the important class of halide scintillators, the particle dispersion is found to be more influential than the largest phonon energy in determining the thermalization distance.

  18. Monte Carlo simulation of electron thermalization in scintillator materials: Implications for scintillator nonproportionality

    Energy Technology Data Exchange (ETDEWEB)

    Prange, Micah P. [Physical and Computational Sciences Directorate, Pacific Northwest National Laboratory, Richland, Washington 99352, USA; Xie, YuLong [Energy and Environment Directorate, Pacific Northwest National Laboratory, Richland, Washington 99352, USA; Campbell, Luke W. [National Security Directorate, Pacific Northwest National Laboratory, Richland, Washington 99352, USA; Gao, Fei [Department of Nuclear Engineering and Radiological Sciences, University of Michigan, Ann Arbor, Michigan 48109, USA; Kerisit, Sebastien [Physical and Computational Sciences Directorate, Pacific Northwest National Laboratory, Richland, Washington 99352, USA

    2017-12-21

    The lack of reliable quantitative estimates of the length and time scales associated with hot electron thermalization after a gamma-ray induced energy cascade obscures the interplay of various microscopic processes controlling scintillator performance and hampers the search for improved detector materials. We apply a detailed microscopic kinetic Monte Carlo model of the creation and subsequent thermalization of hot electrons produced by gamma irradiation of six important scintillating crystals to determine the spatial extent of the cloud of excitations produced by gamma rays and the time required for the cloud to thermalize with the host lattice. The main ingredients of the model are ensembles of microscopic track structures produced upon gamma excitation (including the energy distribution of the excited carriers), numerical estimates of electron-phonon scattering rates, and a calculated particle dispersion to relate the speed and energy of excited carriers. All these ingredients are based on first-principles density functional theory calculations of the electronic and phonon band structures of the materials. Details of the Monte Carlo model are presented along with results for thermalization time and distance distributions. These results are discussed in light of previous work. It is found that among the studied materials, calculated thermalization distances are positively correlated with measured nonproportionality. In the important class of halide scintillators, the particle dispersion is found to be more influential than the largest phonon energy in determining the thermalization distance.

  19. Cosmogenic nuclides in cometary materials: Implications for rate of mass loss and exposure history

    International Nuclear Information System (INIS)

    Herzog, G.F.; Englert, P.A.J.; Reedy, R.C.

    1989-01-01

    As planned, the Rosetta mission will return to earth with a 10-kg core and a 1-kg surface sample from a comet. The selection of a comet with low current activity will maximize the chance of obtaining material altered as little as possible. Current temperature and level of activity, however, may not reliably indicate previous values. Fortunately, from measurements of the cosmogenic nuclide contents of cometary material, one may estimate a rate of mass loss in the past and perhaps learn something about the exposure history of the comet. Perhaps the simplest way to estimate the rate of mass loss is to compare the total inventories of several long-lived cosmogenic radionuclides with the values expected on the basis of model calculations. Although model calculations have become steadily more reliable, application to bodies with the composition of comets will require some extension beyond the normal range of use. In particular, the influence of light elements on the secondary particle cascade will need study, in part through laboratory irradiations of volatile-rich materials. In the analysis of cometary data, it would be valuable to test calculations against measurements of short-lived isotopes

  20. The Impact of Space Flight on Survival and Interaction of Cupriavidus metallidurans CH34 with Basalt, a Volcanic Moon Analog Rock

    Directory of Open Access Journals (Sweden)

    Natalie Leys

    2017-04-01

    Full Text Available Microbe-mineral interactions have become of interest for space exploration as microorganisms could be used to biomine from extra-terrestrial material and extract elements useful as micronutrients in life support systems. This research aimed to identify the impact of space flight on the long-term survival of Cupriavidus metallidurans CH34 in mineral water and the interaction with basalt, a lunar-type rock in preparation for the ESA spaceflight experiment, BIOROCK. Therefore, C. metallidurans CH34 cells were suspended in mineral water supplemented with or without crushed basalt and send for 3 months on board the Russian FOTON-M4 capsule. Long-term storage had a significant impact on cell physiology and energy status (by flow cytometry analysis, plate count and intracellular ATP measurements as 60% of cells stored on ground lost their cell membrane potential, only 17% were still active, average ATP levels per cell were significantly lower and cultivability dropped to 1%. The cells stored in the presence of basalt and exposed to space flight conditions during storage however showed less dramatic changes in physiology, with only 16% of the cells lost their cell membrane potential and 24% were still active, leading to a higher cultivability (50% and indicating a general positive effect of basalt and space flight on survival. Microbe-mineral interactions and biofilm formation was altered by spaceflight as less biofilm was formed on the basalt during flight conditions. Leaching from basalt also changed (measured with ICP-OES, showing that cells release more copper from basalt and the presence of cells also impacted iron and magnesium concentration irrespective of the presence of basalt. The flight conditions thus could counteract some of the detrimental effects observed after the 3 month storage conditions.

  1. Study of the mechanical properties of hybrid composite basalt / alumina / shells for brake lining pads

    Science.gov (United States)

    Adi Atmika, I. K.; Ary Subagia, IDG.; Surata, I. W.; Sutantra, I. N.

    2017-05-01

    Brake lining pad as one of the active safety components in motor vehicles has been studied thoroughly. Asbestos is the main material forming the brake in addition to other alloy materials that have a negative impact on health and the environment. This paper explain the behavior of hybrid composites phenolic resin with basalt/alumina/clamshell powder reinforced on brake lining pad. This materials has been manufactured use compaction and sintering process through any steps, that an emphasis of 2,000 kg for 30 minutes at a constant temperature of 150° C. The research aims to investigate hardness characteristic of hybrid composite that test using the vickers according to standard ASTM E-384. The reinforced materials and phenolic resin composition is 60%: 40%. The results show for the average hardness VHN to 24.18, 25.11, 26.34, 27.21 and 28.83. The average hardness hybrid composite shows the hardness harder than asbestos materials.

  2. Exploration of H2O-CO2 Solubility in Alkali Basalt at low-H2O

    Science.gov (United States)

    Roggensack, K.; Allison, C. M.; Clarke, A. B.

    2017-12-01

    A number of recent experimental studies have found conflicting evidence for and against the influence of H2O on CO2 solubility in basalt and alkali-rich mafic magma (e.g. Behrens et al., 2009; Shishkina et al., 2010;2014; Iacono-Marziano et al., 2012). Some of the uncertainty is due to the error with spectroscopic determination (FTIR) of carbon and the challenge of controlling H2O abundance in experiments. It's been widely observed that even experimental capsules without added H2O may produce hydrous glasses containing several wt.% H2O. We conducted fluid-saturated, mixed-fluid (H2O-CO2) experiments to determine the solubility in alkali basalt with particular emphasis on conditions at low-H2O. To limit possible H2O contamination, materials were dried prior to loading and experimental capsules were sealed under vacuum. Experiments were run using a piston-cylinder, in Pt (pre-soaked in Fe) or AuPd capsules and operating at pressures from 400 to 600 MPa. Post-run the capsules were punctured under vacuum and fluids were condensed, separated, and measured by mercury manometry. A comparison between two experiments run at the same temperature and pressure conditions but with different fluid compositions illustrates the correlation between carbonate and H2O solubility. Uncertainties associated with using concentrations calculated from FTIR data can be reduced by directly comparing analyses on wafers of similar thickness. We observe that the experiment with greater H2O absorbance also has a higher carbonate absorbance than the experiment with lower H2O absorbance. Since the experiments were run at the same pressure, the experiment with more water-rich fluid, and higher dissolved H2O, has lower CO2 fugacity, but surprisingly has higher dissolved CO2 content. Overall, the results show two distinct trends. Experiments conducted at low-H2O (0.5 to 0.8 wt.%) show lower dissolved CO2 than those conducted at moderate-H2O (2 to 3 wt.%) at similar CO2 fugacity. These data show that

  3. Origin of co-existing basalts, high-Mg andesites, and adakites in the SW Japan hot subduction system

    Science.gov (United States)

    Kimura, J.; Kunikiyo, T.; Osaka, I.; Shimoshioiri, Y.; Katakuse, M.; Kakubuchi, S.; Nagao, T.; Furuyama, K.; Kamei, A.; Nakajima, J.; Stern, R. J.; Gill, J. B.

    2012-12-01

    In response to subduction of the young, hot Shikoku Basin of the Philippine Sea Plate (PSP) slab, arc magmas have been active throughout the late Cenozoic (<13 Ma) in the SW Japan arc. Extremely variable magma types occurred including oceanic island-type basalt (OIB), shoshonitc to mildly alkalic to sub-alkalic basalts with arc signatures, high-Mg andesites (HMAs), and adakitic andesites and dacites. The OIB-type basalts preceded the arc-type magmas. Therefore, the transition from OIB- to arc-types was related to opening of the Japan of Sea back-arc basin and subsequent re-initiation of PSP subduction. However, both the origin and tectonic implications of this magmatism are debated. Consequently, we analyzed the bulk rock geochemistry of 340 lava samples from seven Quaternary volcanoes and investigated their sources and melting conditions using a geochemical mass balance model, Arc Basalt Simulator version 4 (ABS4). Comparison to basement granitoids precludes adakite genesis in the lower crust. Instead, the ABS4 model suggests that the adakites are mostly slab melts plus minor interaction with mantle wedge peridotite (PERID). Increasing involvement of PERID during slab melt-fluxed mantle melting explains fairly well the geochemical variations of the shoshonites, mildly alkalic to sub-alkalic basalts, and HMAs. We propose that the generation of various magma types in the late Cenozoic SW Japan arc originated simply by "slab melt-fluxed mantle melting" with large variations in melting conditions including depth, temperature, degree of melting, and flux fractions. Such volcanism has been continuous from 13 Ma (Setouchi HMA) to the present, so that the hot subduction system, involving subduction of the Shikoku Basin spreading ridge, should be continuous since 13 Ma beneath the SW Japan arc. Our results further suggest that this atypically hot system generated diverse primary arc magmas from various degrees of flux melting even though the slab source components and sub

  4. Development of materials to support parents whose babies cry excessively: findings and health service implications.

    Science.gov (United States)

    Long, Jaqui; Powell, Charlotte; Bamber, Deborah; Garratt, Rosemary; Brown, Jayne; Dyson, Sue; James-Roberts, Ian St

    2018-01-10

    Aim To develop evidence-based materials which provide information and support for parents who are concerned about their baby's excessive crying. As well as meeting these parents' needs, the aim was to develop a package of materials suitable for use by the UK National Health Service (NHS). Parents report that around 20% of infants in Western countries cry excessively without an apparent reason during the first four months of age. Traditionally, research has focused on the crying and its causes. However, evidence is growing that how parents evaluate and respond to the crying needs to receive equal attention. This focus encompasses parental resources, vulnerabilities, well-being and mental health. At present, the UK NHS lacks a set of routine provisions to support parents who are concerned about their baby's excessive crying. The rationales, methods and findings from a study developing materials for this purpose are reported. Following a literature review, 20 parents whose babies previously cried excessively took part in focus groups or interviews. They provided reports on their experiences and the supports they would have liked when their baby was crying excessively. In addition, they identified their preferred delivery methods and devices for accessing information and rated four example support packages identified by the literature review. Findings During the period their baby cried excessively, most parents visited a health service professional and most considered these direct contacts to have provided helpful information and support. Websites were similarly popular. Telephones and tablets were the preferred means of accessing online information. Groups to meet other parents were considered an important additional resource by all the parents. Three package elements - a Surviving Crying website, a printed version of the website and a programme of Cognitive Behaviour Therapy-based support sessions delivered to parents by a qualified practitioner, were developed for

  5. Implications of Steam Generator Fouling on the Degradation of Material and Thermal Performance

    Science.gov (United States)

    Turner, Carl W.

    Fouling of steam generators has a significant negative impact on the material and thermal performance the steam generators of pressurized water reactors. Corrosion products that originate from various components in the steam cycle of a nuclear power plant get pumped forward with the feed water to steam generators where they deposit on the tube bundle, tube support structure and the tube sheet. Heavy accumulation of deposit within the steam generator has led to some serious operational problems, including loss of thermal performance, under deposit corrosion, steam generator level oscillations, flow accelerated corrosion of carbon steel tube support plates and the failure of steam generator tubes due to high cycle fatigue.

  6. The radiological implications of using by-product gypsum as a building material

    International Nuclear Information System (INIS)

    O'Riordan, M.C.; Duggan, M.J.; Rose, W.B.; Bradford, G.F.

    1972-12-01

    By-product gypsum, produced as a waste in the phosphate industry, could be used in bulk as a building material, but it has a higher radium content than other building materials and thus raises the question whether or not the resulting radiation doses to individuals and to the population of the country as a whole are acceptable. The typical radium content is 25 pCi/g, and the corresponding dose rate from γ rays to the gonads and bone-marrow of the occupants of a house would be 30 mrad/y, if by-product gypsum were a substantial constituent. This is comparable with the regional variations in the dose rate due to natural background radiation in Great Britain and less than the local variations. If as many as 10% of all new houses were eventually so constructed, the resulting gonad dose rate averaged over the population would ultimately reach 3 mrad/y, or about 3% of that from the natural background. The report also deals with exposures to β radiation and to radon; these exposures are less than the regional variations in natural exposures. All the annual doses are at least a factor of 10 below the dose limits recommended by the International Commission on Radiological Protection for exposure of members of the public; these dose limits relate to the total exposure from all sources of radiation except natural background and exposures for medical purposes. (author)

  7. Plasma-material interactions in current tokamaks and their implications for next step fusion reactors

    International Nuclear Information System (INIS)

    Federici, G.; Skinner, C.H.; Brooks, J.N.

    2001-01-01

    The major increase in discharge duration and plasma energy in a next step DT fusion reactor will give rise to important plasma-material effects that will critically in influence its operation, safety and performance. Erosion will increase to a scale of several centimetres from being barely measurable at a micron scale in today's tokamaks. Tritium co-deposited with carbon will strongly affect the operation of machines with carbon plasma facing components. Controlling plasma-wall interactions is critical to achieving high performance in present day tokamaks, and this is likely to continue to be the case in the approach to practical fusion reactors. Recognition of the important consequences of these phenomena stimulated an internationally co-ordinated effort in the part of plasma-surface interactions supporting the Engineering Design Activities of the International Thermonuclear Experimental Reactor project (ITER), and significant progress has been made in better understanding these issues. The paper reviews the underlying physical processes and the existing experimental database of plasma-material inter actions both in tokamaks and laboratory simulation facilities for conditions of direct relevance to next step fusion reactors. Two main topical groups of interaction are considered: (i) erosion/redeposition from plasma sputtering and disruptions, including dust and flake generation and (ii) tritium retention and removal. The use of modelling tools to interpret the experimental results and make projections for conditions expected in future devices is explained. Outstanding technical issues and specific recommendations on potential R and D avenues for their resolution are presented. (author)

  8. Plasma-material interactions in current tokamaks and their implications for next-step fusion reactors

    International Nuclear Information System (INIS)

    Federici, G.; Skinner, C.H.; Brooks, J.N.

    2001-01-01

    The major increase in discharge duration and plasma energy in a next-step DT fusion reactor will give rise to important plasma-material effects that will critically influence its operation, safety and performance. Erosion will increase to a scale of several cm from being barely measurable at a micron scale in today's tokamaks. Tritium co-deposited with carbon will strongly affect the operation of machines with carbon plasma-facing components. Controlling plasma wall interactions is critical to achieving high performance in present-day tokamaks and this is likely to continue to be the case in the approach to practical fusion reactors. Recognition of the important consequences of these phenomena has stimulated an internationally co-ordinated effort in the field of plasma-surface interactions supporting the engineering design activities of the international thermonuclear experimental reactor project (ITER) and significant progress has been made in better understanding these issues. This paper reviews the underlying physical processes and the existing experimental database of plasma-material interactions both in tokamaks and laboratory simulation facilities for conditions of direct relevance to next-step fusion reactors. Two main topical groups of interactions are considered: (i) erosion/re-deposition from plasma sputtering and disruptions, including dust and flake generation, (ii) tritium retention and removal. The use of modelling tools to interpret the experimental results and make projections for conditions expected in future devices is explained. Outstanding technical issues and specific recommendations on potential R and D avenues for their resolution are presented. (orig.)

  9. The Fate of Failed Bank Material and Implications for Lateral Retreat: Lake Tahoe Basin

    Science.gov (United States)

    Simon, A.; Thomas, R. E.

    2009-12-01

    The ability to deterministically predict the critical conditions for streambank failure in alluvial materials has improved markedly in recent years. Analytic tools such as the Bank-Stability and Toe-Erosion Model (BSTEM) account for a broad range of controlling processes and factors including hydraulic erosion of the bank toe, positive and negative pore-water pressures, layers of varying geotechnical resistance and root reinforcement. When failure is predicted, the failed mass is assumed to be transported away from the section by the flow, either as a single mass or as dispersed aggregates. Field observations indicate, however, that in cases where cohesive strength is high, either due to the effective cohesion of the soil skeleton or due to dense mats of fine roots, the failed block comes to rest in the vicinity of the bank toe. In this case, the resistance of the bank-toe region to hydraulic scour may be increased markedly and resistance to geotechnical failure may also be increased by buttressing. Conversely, deposition of blocks at bank toes may cause flow acceleration and scour landward of the block, resulting in further undercutting of the bank mass. Failure to account for these processes can lead to errors in predicting of rates of failure frequency, lateral retreat and streambank loadings.Once deposited at the bank toe, failed blocks can be eroded by hydraulic forces either as a mass and/or by erosion of aggregates comprising the block. Field research on the nature of hydraulic resistance and block erosion has been conducted along selected reaches of the Upper Truckee River (UTR) and Trout Creek, Lake Tahoe Basin, California. Block materials are generally characterized by lower apparent cohesive strength than their in situ counterparts due to the lower values of matric suction owing to their proximity to the water surface. Still, submerged jet-test device conducted in root-permeated blocks show critical shear stresses one to two orders of magnitude greater

  10. Clast-fabric development in a shearing granular material: Implications for subglacial till and fault gouge

    Science.gov (United States)

    Hooyer, T.S.; Iverson, N.R.

    2000-01-01

    Elongate clasts in subglacial till and in fault gouge align during shearing, but the relation between clast-fabric strength and cumulative shear strain for such materials is effectively unknown. This relation was explored in experiments with a large ring-shear device in which a till and a viscous putty that contained isolated clasts were sheared to high strains. As expected, rotation of clasts in the putty is closely approximated by the theory of G.B. Jeffrey, who derived the orbits of rigid ellipsoids in a slowly shearing fluid. Clast rotation in the till, however, is strikingly different. Rather than orbiting through the shear plane as predicted by Jeffery, most clasts rotate into the shear plane and remain there, resulting in strong fabrics regardless of the aspect ratios and initial orientations of clasts. This divergent behavior is likely due to slip of the till matrix along the surfaces of clasts, which is a natural expectation in a granular material but violates the no-slip condition of Jeffery's model. These results do not support the widespread belief that subglacial till deformation results in weak clast fabrics. Thus, many tills with weak fabrics thought to have been sheared subglacially to high strains, like many basal tills of the Laurentide Ice Sheet, may have been sheared only slightly with little effect on either ice-sheet dynamics or sediment transport. In addition, these results indicate that in simple shear the rotation of clasts in till and in fault gouge is best analyzed with the model of A. March, who treated inclusions as passive markers.

  11. Plasma-material Interactions in Current Tokamaks and their Implications for Next-step Fusion Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Federici, G.; Skinner, C.H.; Brooks, J.N.; Coad, J.P.; Grisolia, C. [and others

    2001-01-10

    The major increase in discharge duration and plasma energy in a next-step DT [deuterium-tritium] fusion reactor will give rise to important plasma-material effects that will critically influence its operation, safety, and performance. Erosion will increase to a scale of several centimeters from being barely measurable at a micron scale in today's tokamaks. Tritium co-deposited with carbon will strongly affect the operation of machines with carbon plasma-facing components. Controlling plasma wall interactions is critical to achieving high performance in present-day tokamaks and this is likely to continue to be the case in the approach to practical fusion reactors. Recognition of the important consequences of these phenomena has stimulated an internationally coordinated effort in the field of plasma-surface interactions supporting the Engineering Design Activities of the International Thermonuclear Experimental Reactor (ITER) project and significant progress has been made in better under standing these issues. This paper reviews the underlying physical processes and the existing experimental database of plasma-material interactions both in tokamaks and laboratory simulation facilities for conditions of direct relevance to next-step fusion reactors. Two main topical groups of interactions are considered: (i) erosion/redeposition from plasma sputtering and disruptions, including dust and flake generation, (ii) tritium retention and removal. The use of modeling tools to interpret the experimental results and make projections for conditions expected in future devices is explained. Outstanding technical issues and specific recommendations on potential R and D [Research and Development] avenues for their resolution are presented.

  12. Plasma-material Interactions in Current Tokamaks and their Implications for Next-step Fusion Reactors

    International Nuclear Information System (INIS)

    Federici, G.; Skinner, C.H.; Brooks, J.N.; Coad, J.P.; Grisolia, C.

    2001-01-01

    The major increase in discharge duration and plasma energy in a next-step DT (deuterium-tritium) fusion reactor will give rise to important plasma-material effects that will critically influence its operation, safety, and performance. Erosion will increase to a scale of several centimeters from being barely measurable at a micron scale in today's tokamaks. Tritium co-deposited with carbon will strongly affect the operation of machines with carbon plasma-facing components. Controlling plasma wall interactions is critical to achieving high performance in present-day tokamaks and this is likely to continue to be the case in the approach to practical fusion reactors. Recognition of the important consequences of these phenomena has stimulated an internationally coordinated effort in the field of plasma-surface interactions supporting the Engineering Design Activities of the International Thermonuclear Experimental Reactor (ITER) project and significant progress has been made in better under standing these issues. This paper reviews the underlying physical processes and the existing experimental database of plasma-material interactions both in tokamaks and laboratory simulation facilities for conditions of direct relevance to next-step fusion reactors. Two main topical groups of interactions are considered: (i) erosion/redeposition from plasma sputtering and disruptions, including dust and flake generation, (ii) tritium retention and removal. The use of modeling tools to interpret the experimental results and make projections for conditions expected in future devices is explained. Outstanding technical issues and specific recommendations on potential R and D (Research and Development) avenues for their resolution are presented

  13. Preliminary Hydrogeologic Characterization Results from the Wallula Basalt Pilot Study

    Energy Technology Data Exchange (ETDEWEB)

    B.P. McGrail; E. C. Sullivan; F. A. Spane; D. H. Bacon; G. Hund; P. D. Thorne; C. J. Thompson; S. P. Reidel; F. S. Colwell

    2009-12-01

    The DOE's Big Sky Regional Carbon Sequestration Partnership has completed drilling the first continental flood basalt sequestration pilot borehole to a total depth (TD) of 4,110 feet on the Boise White Paper Mill property at Wallula, Washington. Site suitability was assessed prior to drilling by the 2007-2008 acquisition, processing and analysis of a four-mile, five-line three component seismic swath, which was processed as a single data-dense line. Analysis of the seismic survey data indicated a composite basalt formation thickness of {approx}8,000 feet and absence of major geologic structures (i.e., faults) along the line imaged by the seismic swath. Drilling of Wallula pilot borehole was initiated on January 13, 2009 and reached TD on April 6, 2009. Based on characterization results obtained during drilling, three basalt breccia zones were identified between the depth interval of 2,716 and 2,910 feet, as being suitable injection reservoir for a subsequent CO2 injection pilot study. The targeted injection reservoir lies stratigraphically below the massive Umtanum Member of the Grande Ronde Basalt, whose flow-interior section possesses regionally recognized low-permeability characteristics. The identified composite injection zone reservoir provides a unique and attractive opportunity to scientifically study the reservoir behavior of three inter-connected reservoir intervals below primary and secondary caprock confining zones. Drill cuttings, wireline geophysical logs, and 31one-inch diameter rotary sidewall cores provided geologic data for characterization of rock properties. XRF analyses of selected rock samples provided geochemical characterizations of the rocks and stratigraphic control for the basalt flows encountered by the Wallula pilot borehole. Based on the geochemical results, the pilot borehole was terminated in the Wapshilla Ridge 1 flow of the Grande Ronde Basalt Formation. Detailed hydrologic test characterizations of 12 basalt interflow

  14. Mineralization of Bacteria in Terrestrial Basaltic Rocks: Comparison With Possible Biogenic Features in Martian Meteorite Allan Hills 84001

    Science.gov (United States)

    Thomas-Keprta, K. L.; McKay, D. S.; Wentworth, S. J.; Stevens, T. O.; Taunton, A. E.; Allen, C. C.; Gibson, E. K., Jr.; Romanek, C. S.

    1998-01-01

    The identification of biogenic features altered by diagenesis or mineralization is important in determining whether specific features in terrestrial rocks and in meteorites may have a biogenic origin. Unfortunately, few studies have addressed the formation of biogenic features in igneous rocks, which may be important to these phenomena, including the controversy over possible biogenic features in basaltic martian meteorite ALH84001. To explore the presence of biogenic features in igneous rocks, we examined microcosms growing in basaltic small-scale experimental growth chambers or microcosms. Microbial communities were harvested from aquifers of the Columbia River Basalt (CRB) group and grown in a microcosm containing unweathered basalt chips and groundwater (technique described in. These microcosms simulated natural growth conditions in the deep subsurface of the CRB, which should be a good terrestrial analog for any putative martian subsurface ecosystem that may have once included ALH84001. Here we present new size measurements and photomicrographs comparing the putative martian fossils to biogenic material in the CRB microcosms. The range of size and shapes of the biogenic features on the CRB microcosm chips overlaps with and is similar to those on ALH84001 chips. Although this present work does not provide evidence for the biogenicity of ALH84001 features, we believe that, based on criteria of size, shape, and general morphology, a biogenic interpretation for the ALH84001 features remains plausible.

  15. Global Warming Implications of the Use of By-Products and Recycled Materials in Western Australia’s Housing Sector

    Directory of Open Access Journals (Sweden)

    Krishna Lawania

    2015-10-01

    Full Text Available Western Australia’s housing sector is growing rapidly and around half a million houses are expected to be built by 2030, which not only will result in increased energy and resources demand but will have socio-economic impacts. Majority of Western Australians live in detached houses made of energy intensive clay bricks, which have a high potential to generate construction and demolition (C&D waste. Therefore, there is a need to look into the use of alternative materials and construction methods. Due to Western Australia’s temperate climate, concrete could not only offer a comfortable living space but an operational energy saving also can be achieved. This paper has assessed the global warming implications of cast in-situ concrete sandwich wall system as an alternative to clay brick walls (CBW with partial replacement of cement in concrete with by-products such as fly ash (FA and ground granulated blast furnace slag (GGBFS, natural aggregate (NA with recycled crushed aggregate (RCA, natural sand (NS with manufactured sand (MS and, polyethylene terephthalate (PET foam core as a replacement to polystyrene core for construction of a typical 4 × 2 × 2 detached house in Perth. Life cycle management (LCM approach has been used to determine global warming reduction benefits due to the use of available by-products and recycled materials in Western Australian houses.

  16. Global Warming Implications of the Use of By-Products and Recycled Materials in Western Australia’s Housing Sector

    Science.gov (United States)

    Lawania, Krishna; Sarker, Prabir; Biswas, Wahidul

    2015-01-01

    Western Australia’s housing sector is growing rapidly and around half a million houses are expected to be built by 2030, which not only will result in increased energy and resources demand but will have socio-economic impacts. Majority of Western Australians live in detached houses made of energy intensive clay bricks, which have a high potential to generate construction and demolition (C&D) waste. Therefore, there is a need to look into the use of alternative materials and construction methods. Due to Western Australia’s temperate climate, concrete could not only offer a comfortable living space but an operational energy saving also can be achieved. This paper has assessed the global warming implications of cast in-situ concrete sandwich wall system as an alternative to clay brick walls (CBW) with partial replacement of cement in concrete with by-products such as fly ash (FA) and ground granulated blast furnace slag (GGBFS), natural aggregate (NA) with recycled crushed aggregate (RCA), natural sand (NS) with manufactured sand (MS) and, polyethylene terephthalate (PET) foam core as a replacement to polystyrene core for construction of a typical 4 × 2 × 2 detached house in Perth. Life cycle management (LCM) approach has been used to determine global warming reduction benefits due to the use of available by-products and recycled materials in Western Australian houses.

  17. TRU waste form studies with special reference to iron-enriched basalt: 1980. Annual report

    International Nuclear Information System (INIS)

    Flinn, J.E.; Henslee, S.P.; Kelsey, P.V. Jr.

    1981-06-01

    Material studies were performed on iron-enriched basalt (IEB) as a waste form containment medium for transuranic wastes. Specimens from laboratory scale, as well as large scale melts, were used in the evaluation. The studies included melting and casting, slag-refractory interaction, slag fruit assessments, volatility of sodium salts from IEB melts, chemical and structure homogeneity, metallic dissolution tests, physical properties, and devitrification associated with the development of mineral phases. In addition, durability tests, which included leaching and mechanical behavior, were performed

  18. Materialism.

    Science.gov (United States)

    Melnyk, Andrew

    2012-05-01

    Materialism is nearly universally assumed by cognitive scientists. Intuitively, materialism says that a person's mental states are nothing over and above his or her material states, while dualism denies this. Philosophers have introduced concepts (e.g., realization and supervenience) to assist in formulating the theses of materialism and dualism with more precision, and distinguished among importantly different versions of each view (e.g., eliminative materialism, substance dualism, and emergentism). They have also clarified the logic of arguments that use empirical findings to support materialism. Finally, they have devised various objections to materialism, objections that therefore serve also as arguments for dualism. These objections typically center around two features of mental states that materialism has had trouble in accommodating. The first feature is intentionality, the property of representing, or being about, objects, properties, and states of affairs external to the mental states. The second feature is phenomenal consciousness, the property possessed by many mental states of there being something it is like for the subject of the mental state to be in that mental state. WIREs Cogn Sci 2012, 3:281-292. doi: 10.1002/wcs.1174 For further resources related to this article, please visit the WIREs website. Copyright © 2012 John Wiley & Sons, Ltd.

  19. Magnesium isotopic variation of oceanic island basalts generated by partial melting and crustal recycling

    Science.gov (United States)

    Zhong, Yuan; Chen, Li-Hui; Wang, Xiao-Jun; Zhang, Guo-Liang; Xie, Lie-Wen; Zeng, Gang

    2017-04-01

    Ocean island basalts (OIBs) are geochemically diverse in radiogenic isotopes, a feature that is commonly ascribed to record the chemical heterogeneity of their deep-mantle source, where significant compositional variation relates to variable amounts of ancient recycled crustal material. Although Mg is a major constituent of the mantle, it is still unclear whether Mg isotopes of OIBs predominantly correspond to deep-mantle source heterogeneity or processes such as partial melting. Here, we present Mg isotopic and trace-element compositional data for OIBs from the Hawaii islands, the Louisville seamounts, and for altered oceanic crust samples from the South Pacific. The δ26Mg value range of these OIBs is - 0.29 ± 0.07 ‰ (2SD, n = 17), which is a variation approximately twice as large as the known compositional variation of the peridotitic mantle (- 0.23 ± 0.04 ‰, 2SD). Moreover, alkaline basalt (- 0.31 ± 0.04 ‰, 2SD, n = 12) is relatively enriched in light Mg isotopes compared to tholeiitic basalt (- 0.24 ± 0.02 ‰, 2SD, n = 5). In contrast, altered oceanic crust analyzed in this study has heavier Mg isotopic composition (- 0.18 ± 0.08 ‰, 2SD, n = 13) relative to the basalts and to the peridotitic mantle. An evaluation of our and published data shows that the δ26Mg values of most OIBs negatively correlate with melting-sensitive trace-element ratios, but that they are uncorrelated with source-sensitive elemental ratios. This implies that Mg isotopic variation in most OIBs is largely controlled by variable degrees of partial melting and not by source heterogeneity. Negative correlation between Nb/Zr (or La/Sm) versus δ26Mg suggests that altered oceanic crust with heavier Mg isotopic composition is a more suitable source candidate for common OIBs. However, for a given melting degree, Louisville basalts have lower δ26Mg values than other OIBs, suggesting a different source, e.g. a peridotitic mantle. Modeling calculations suggest that melting of both

  20. Radiological safety and environmental implications in beach mineral industry due to naturally occurring radioactive materials

    International Nuclear Information System (INIS)

    Pillai, P.M.B.; Haridasan, P.P.; Maniyan, C.G.; Khan, A.H.

    2002-01-01

    The presence of monazite (primary ore of Thorium) along with ilmenite and other minerals in the beach sand deposits of coastal regions of South India has made some of these coastal areas prominent among Natural High Background Radiation Areas (NHBRA) in the world. The beach mineral industries are situated in populated areas in these NHBRAs. The radiation background prevailing in these areas due to the presence of the Naturally Occurring Radioactive Materials (NORM) Thorium with traces of Uranium and their decay products had been found to result in estimated percaput annual external exposures ranging from 3 to 25 mSv to the population at NHBRA depending on the monazite content of the soil in the area. The internal exposures estimated are of the order of 1 to 2 mSv per year. The mining of minerals and refilling of the mined out areas with mineral free sand and rehabilitation of the area is found to reduce the external radiation fields by a factor of 3. The notional environmental external radiation exposures to the population occupying this modified NHBRA also reduce correspondingly. (author)

  1. UV Induced Degradation of Polycarbonate-Based Lens Materials and Implications for the Heath Care Field

    Science.gov (United States)

    Harkay, J. R.; Henry, Jerry

    2006-10-01

    Experimental research is being carried out at Keene State at the undergraduate level that utilizes facilities in both physics and chemistry to study the effects of mono- and polychromatic UV radiation from various sources, including a Deuterium lamp, a solarization unit (at Polyonics, a local industry), and the Sun, to study the photodegradation of polycarbonate-based lens materials used to produce eyewear. Literature in the field of optometry and ophthalmology indicates a correlation between exposure to the UVB band of natural sunlight and the onset of cataract formation, as well as other eye disorders. The public is usually advised that plastic eyeglass lenses will provide protection from this damaging radiation. It is well known that polycarbonate plastic ``yellows'' when exposed to intense sunlight and, particularly, UV light^1,2, either via photo-Fries rearrangement or by a photooxidative process, forming polyconjugated systems and is an industrial concern primarily for cosmetic reasons. We have preliminary data, however, that indicates that the yellowing'' is an indication of a more sinister problem in the case of eyeglasses in that it is accompanied by an increase in transmissivity in the UVB band where the wearer expects and needs protection. Our group includes a local optometrist who will share results with peers in his field. [1] A. Andrady, J. Polymer Sci., 42, 1991 [2] E. P. Gorelov, Inst. Khim. Fiz., Russian Federation

  2. UV Induced Degradation of Polycarbonate-Based Lens Materials and Implications for the Heath Care Field

    Science.gov (United States)

    Harkay, J. Russell; Henry, Jerry

    2007-04-01

    Experimental undergraduate research at Keene State College has utilized facilities in physics and chemistry and at Polyonics, a local firm to study the effects of mono- and polychromatic UV radiation from various sources, including a Deuterium lamp, a solarization unit, a monochromator, and natural sunlight to study the photodegradation of polycarbonate-based lens materials used to produce eyewear using spectrophotometry and FTIR analysis. Ophthalmologic literature indicates a correlation between exposure to the UVB band of sunlight and the onset of cataract formation and macular degeneration. It is well known that polycarbonate plastic ``yellows'' when exposed to intense sunlight and, particularly, UV light either via photo-Fries rearrangement or by a photo oxidative process, forming polyconjugated systems and is a concern primarily for cosmetic reasons. Our data indicates that the ``yellowing'' is an indication of a more sinister problem in the case of eyeglasses in that spectrophotometric comparison shows it is accompanied by an increase in transmissivity in the UVB band where the wearer expects and needs protection. FTIR results indicate a degradation of molecular stabilizers and the appearance of free radicals that indicate a breakdown of the resin's chemical structure. To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2007.NES07.B1.4

  3. Material flows of mobile phones and accessories in Nigeria: Environmental implications and sound end-of-life management options

    International Nuclear Information System (INIS)

    Osibanjo, Oladele; Nnorom, Innocent Chidi

    2008-01-01

    Presently, Nigeria is one of the fastest growing Telecom markets in the world. The country's teledensity increased from a mere 0.4 in 1999 to 10 in 2005 following the liberalization of the Telecom sector in 2001. More than 25 million new digital mobile lines have been connected by June 2006. Large quantities of mobile phones and accessories including secondhand and remanufactured products are being imported to meet the pent-up demand. This improvement in mobile telecom services resulted in the preference of mobile telecom services to fixed lines. Consequently, the contribution of fixed lines decreased from about 95% in year 2000 to less than 10% in March 2005. This phenomenal progress in information technology has resulted in the generation of large quantities of electronic waste (e-waste) in the country. Abandoned fixed line telephone sets estimated at 120,000 units are either disposed or stockpiled. Increasing quantities of waste mobile phones estimated at 8 million units by 2007, and accessories will be generated. With no material recovery facility for e-waste and/or appropriate solid waste management infrastructure in place, these waste materials end up in open dumps and unlined landfills. These practices create the potential for the release of toxic metals and halocarbons from batteries, printed wiring boards, liquid crystal display and plastic housing units. This paper presents an overview of the developments in the Nigerian Telecom sector, the material in-flow of mobile phones, and the implications of the management practices for wastes from the Telecom sector in the country

  4. Irradiation conditions of ADS beam window and implications for window material

    International Nuclear Information System (INIS)

    Vladimirov, P.; Moeslang, A.

    2006-01-01

    Accelerator driven systems (ADS) are aimed at incineration of long living radioactive isotopes of spent nuclear reactor fuel, thus providing a solution for nuclear waste utilization. The idea is to couple a subcritical nuclear reactor with a high-energy proton accelerator. Protons interacting with the liquid metal target inside the reactor will produce neutrons with energy sufficient to transform long living fuel isotopes to those with shorter decay time. In some design variants a proton beam guide and window separate the vacuum of the accelerator from the liquid metal target. The window appears to be the most critical component of the whole facility as besides liquid metal corrosion it undergoes irradiation damage from incident protons, from protons and neutrons produced by spallation inside the target as well as from fission neutrons generated in the reactor fuel assemblies. In the present work we have evaluated irradiation conditions of the ADS beam window using Monte Carlo neutron, photon and charged particle transport code MCNPX. The code and the detailed geometric model of the experimental ADS (XADS) facility allow a realistic simulation of the spallation process and transport of generated nucleons as well as evaluation of various damage and operational characteristics like displacement damage, heat deposition, gas and spallation element production rates. Present results based on the reduced beam parameters provide a hope that apart from the liquid metal corrosion (not considered in the present paper) the window material could sustain full operation during the period of 3-4 month between replacements. These results may allow reconsideration of pro and contra of the window and the windowless XADS concepts

  5. Aquatic toxicity of airfield-pavement deicer materials and implications for airport runoff

    Science.gov (United States)

    Corsi, S.R.; Geis, S.W.; Bowman, G.; Failey, G.G.; Rutter, T.D.

    2009-01-01

    Concentrations of airfield-pavement deicer materials (PDM) in a study of airport runoff often exceeded levels of concern regarding aquatic toxicity. Toxicity tests on Vibrio fischeri, Pimephales promelas, Ceriodaphnia dubia, and Pseudokirchneriella subcapitata (commonly known as Selenastrum capricornutum) were performed with potassium acetate (K-Ac) PDM, sodium formate (Na-For) PDM, and with freezing- point depressants (K-Ac and Na-For). Results indicate that toxicity in PDM is driven by the freezing-point depressants in all tests except the Vibrio fisheri test for Na-For PDM which is influenced by an additive. Acute toxicity end points for different organisms ranged from 298 to 6560 mg/L (as acetate) for K-Ac PDM and from 1780 to 4130 mg/L (as formate) for Na- For PDM. Chronic toxicity end points ranged from 19.9 to 336 mg/L (as acetate) for K-Ac PDM and from 584 to 1670 mg/L (as formate) for Na-For PDM. Sample results from outfalls at General Mitchell International Airport in Milwaukee, Wl (GMIA) indicated that 40% of samples had concentrations greater than the aquatic-life benchmark for K-Ac PDM. K-Ac has replaced urea during the 1990s as the most widely used PDM at GMIA and in the United States. Results of ammonia samples from airport outfalls during periods when urea-based PDM was used at GMIA indicated that41% of samples had concentrations exceeding the U.S. Environmental Protection Agency (USEPA) 1 -h water-quality criterion. The USEPA 1-h water-quality criterion for chloride was exceeded in 68% of samples collected in the receiving stream, a result of road-salt runoff from urban influence near the airport. Results demonstrate that PDM must be considered to comprehensively evaluate the impact of chemical deicers on aquatic toxicity in water containing airport runoff. ?? 2009 American Chemical Society.

  6. The chemistry and parent material of urban soils in Bristol (UK): implications for contaminated land assessment.

    Science.gov (United States)

    Giusti, L

    2013-02-01

    An earlier survey of topsoil from parks and allotment in the city of Bristol (UK) revealed the presence of relatively high levels of "pseudo-total" Cd, As, Cu, Pb and Zn, with Cd and As exceeding present UK soil guidelines. This follow-up work aimed at (1) estimating geochemical thresholds for these elements based on "near-total" soil, bedrock and sediment heavy metals and (2) determining the genetic relationship between soil and bedrock using rare earth elements (REEs or lanthanides) as tracers. "Near-total" concentration of 34 elements (Al, Ca, Fe, K, Mg, Na, As, Ba, Cd, Cr, Cu, Li, Mn, Ni, P, Pb, Sc, Ti, V, Zn, Y and the rare earth elements Ce, Dy, Er, Eu, Gd, Ho, La, Lu, Nd, Pr, Sm, Tb, Yb) were obtained by ICP-MS and ICP-OES. The results show that the soil composition is largely controlled by the soil parent material, though extreme outliers are indicative of contamination at a few sites of parkland and allotments. Cumulative frequency plots show the presence of different data sets for which separate "background" values should be determined. The REE data provide evidence that weathering of the underlying sandstone was a determinant factor leading to the relatively high heavy metal enrichment found in soil samples and sediments. Reference to UK soil guidelines to decide on possible remediation measures could be very misleading due to the natural high background levels of some elements in the underlying bedrock. Before defining land as "contaminated", a thorough geochemical investigation is required at local scale in order to produce a more realistic and correct environmental assessment.

  7. Argon Isotopic Dating of Neolithic Jade Artifacts and Raw Materials from Eastern China and Its Implications

    Directory of Open Access Journals (Sweden)

    Su-Jung Chou

    2009-01-01

    Full Text Available The origin of Chinese culture during the Neolithic age has long been a focus of academic debate. The controversy is centered on whether the origins of Neolithic culture in China were singular or more di verse. Con se quently, understanding the spatial distribution of archaeological jade artifacts in the context of the sources of raw jade has been one of the most reason ablemeans to infer the routes of cultural migration and trade activities during the Neo lithic period. It was widely advocated that HeTian Jade from XinJiang was the sole source of jade for all of Neo lithic China. However, the discovery of jade mines at MeiLing (JiangSu Prov ince in 1989 raises the question as to whether raw jade could have come from an alternate source other than XinJiang during this period. Using 40Ar/39Ar laser dating technique, this study at tempts to correlate the formation ages of excavated jade artifacts at LingJiaTan (AnHui Prov ince to the nearby MeiLing jade mines and far away HeTian jade mines, in the hope of trac ing the pos si ble cul ture in ter ac tions and trad ing ac tiv i ties among these ar eas. The re sults show that the for ma tion ages of LingJiaTan jade ar ti facts are around 120 Ma, about the same age as jade from the nearby MeiLing jade mines. In addition, both jades are tremolite with similar chemical compositions and mineral characteristics. There fore, the material source of jade artifacts ex cavated at LingJiaTan archeological site most likely originated from these nearby MeiLing jade mines. By contrast, there is a big difference in the formation ages between Meiling jade artifacts and raw HeTian Jade (277.3 Ma. Based on these results, weconclude that in the Neo lithic age, people living in LingJiaTan (AnHui Province probably had interactions with people around MeiLing (JiangSu Province, but not with peoples of XinJiang Province.

  8. PROPERTIES AND MANAGEMENT IMPLICATIONS OF SOILS FORMED FROM VOLCANIC MATERIALS IN LEMBANG AREA, WEST JAVA

    Directory of Open Access Journals (Sweden)

    Edi Yatno

    2016-10-01

    Full Text Available Soils formed from volcanic materials have a high potential for agricultural development, especially for horticultural crops, tea, and pine trees. Data on the characteristics of these soils are important for the management planning. Six representative soil profiles developed on andesitic volcanic ash and tuff in Lembang area, West Java were studied to determine the soil physical, chemical, and mineralogical properties, to study the relationship between the soil properties, and to classify the soils according to the Soil Taxonomy. The results indicated that all the soils had very deep (>150 cm solum. In general, the volcanic ash soils were darker colored, more granular, more friable, less sticky and less plastic than the volcanic tuff soils. Physically, the ash soils had lower bulk density (0.44-0.73 mg m-3 and higher available water content (13-33% than the tuff soils. Bulk density decreased with increasing allophane. Chemically, the ash soils had higher pHNaF (mostly > 10, higher organic carbon (4.3-6.8% in upper horizons, higher CEC (20- 44 cmolc kg-1, and higher P retention (> 85% than the tuff soils. P retention logarithmically increased with increasing oxalate extractable Al and allophane. The sand fractions of the ash soils were dominated by hornblende, while the tuff soils were predominantly composed of opaque minerals. In the clay fractions, the ash soils were dominated by allophane, whereas the tuff soils showed high contents of gibbsite and metahalloysite. Soils developed on volcanic ash were classified as Thaptic Hapludands and Typic Melanudands, while soils formed from volcanic tuff were classified as Andic Dystrudepts. The low bulk density and friable consistency of the soils contributed to favorable soil tilth. However, high P retention and Al saturation in most soils are limiting factors for plant growth. Application of P fertilizers and liming coupled with efficient placement can be recommended to enhance P availability and

  9. Study of Carbonaceous Material in cherts from Barberton Greenstone Belt and the Astrobiological Implications.

    Science.gov (United States)

    Rull, F.; Venegas, G.; Montero, O.; Medina, J.

    2012-04-01

    Carbonaceous matter is present in chert deposits of Barberton Greenstone Belt (BGB), South Africa. This is a famous place in the world for its Archean geology, wich represents around 3.5 billion years of earth's history. Therefore this area provides us the opportunity to study and understand an important part history of our planet, and also allow to compare with the geological history of other planets in our solar system [1]. Raman micro-spectroscopy has proved to be a very important and non-destructive powerful tool for distinguish micro-sized particles of C-polymorphs, as it is very sensitive to the nature of carbon bonding [2]. The connection between the Raman characterization of these carbonaceous phases with ancient biogenic activity it's of special interest. Cherts of BGB have been interpreted as precipitates or diagenetic replacements of preexisting sedimentary and pyroclastic deposits in a silica saturated Archean ocean [3]. Several layered Samples of cherts from BGB utility for the present study were collected during the expedition carried out in August 2010 sponsored by CNES and ESA. A detailed Raman spectral analysis of carbon C-C vibrations has been performed in the first (1200-1800 cm-1) and second (2500-3200 cm-1) order regions [4]. The results show important changes in the G-D bands in the layered structure of chert. Additionally a UPLC-ESI-QTOF-MS was carried out trying to introduce new insight in the Raman interpretation of the bands and in the possible assignments to particular molecular groups which could be related with biotic or abiotic origin of the carbonaceous material. Among the tentative compounds obtained from UPLC-ESI-QTOF-MS study it is worth to mention hydroxy-lycopene and the hydroxyl derivative of β-carotene (i.e. β-cryptoxanthin), which are carotenoids produced by cyanobacteria. These results are consistent with the presence of 22-Hopanol and Tetrahymanol, which are characteristic hopanoids of photosynthetic cyanobacteria and have

  10. Radio-induced alteration in cordierite - Implications for petrology, gemmology and materials science

    Science.gov (United States)

    Krickl, R.; Nasdala, L.; Grambole, D.; Kaindl, R.

    2009-04-01

    Cordierite is a common metamorphic and magmatic mineral, which is used as petrologic tool for reconstructing the history of its host rock. Further applications include cordierite gemstones and the use of synthetic analogs in ceramics. Cordierite is stable over a wide temperature and pressure range and relatively resistant to chemical alteration; however, its properties can be significantly changed upon the impact of external irradiation. In the course of a comprehensive study, natural radiohaloes in cordierite (a widespread feature caused by the impact of alpha-particles originating from radioactive inclusions) as well as artificial analogs produced by implantation of 8.8 MeV He2+ ions were investigated using modern micro-techniques. Additional irradiation experiments were performed using O6+ ions, electrons and gamma-rays. Ion irradiation causes yellow colouration that is strongly pleochroic, and fades at higher doses. The possibility of radiation-treatment for enhancing the quality of gem-cordierite is discussed. While samples remain crystalline up to doses of 1016 He2+/cm2, the same material is fully amorphised when irradiated with the same dose of 30 MeV O6+ ions. These different observations may help to estimate the performance assessment of cordierite-ceramics in radiated environments. A very important result concerning the petrological use of cordierite is the radio-induced transformation of channel constituents: Inside the irradiated areas the vibrational bands of CO2 decrease in intensity, whereas two new bands appear at 2135 cm-1 (both IR- and Raman-active; cf. Nasdala et al., 2006) and 1550 cm-1 (only Raman-activ). They are assigned to stretching vibrations of carbon monoxide and molecular oxygen, respectively, thus indicating a radio-chemical transformation 2CO2 → 2CO + O2 in alpha-irradiated cordierite. This study yields the first spectroscopic evidence for the irradiation-induced formation of molecular oxygen in cordierite. Polarised vibrational

  11. Age of the youngest Palaeogene flood basalts in East Greenland

    DEFF Research Database (Denmark)

    Heilmann-Clausen, C.; Piasecki, Stefan; Abrahamsen, Niels

    2008-01-01

    results, this constrains the termination of the East Greenland Paleogene Igneous Province to the Early-Middle Eocene transition (nannoplankton chronozones NP13-NP14/earliest NP15). This is 6-8 Ma younger than according to previous biostratigraphic age assignments. The new data show that flood basalt......Intra-basaltic sediments 50 m below the top of the Paleogene lava succession at Kap Dalton, East Greenland, contain dinoflagellate cysts of late Ypresian-earliest Lutetian age, while sediments immediately above the lavas contain an assemblage of early Lutetian age. Combined with paleomagnetic...

  12. Quaternary basaltic volcanism in the Payenia volcanic province, Argentina

    DEFF Research Database (Denmark)

    Søager, Nina

    in basalts from all the studied volcanic fields in Payenia is signs of lower crustal contamination indicating assimilation of, in some cases, large amounts of trace element depleted, mafic, plagioclase-bearing rocks. The northern Payenia is dominated by backarc basalts erupted between late Pliocene to late...... are isotopically similar to the Andean Southern Volcanic Zone arc rocks and their mantle source possibly resembled the source of South Atlantic N-MORB prior to addition of fluids and melts from the subduction channel. However, it must have been more enriched than the estimates of depleted upper mantle from...

  13. Flood basalt volcanism on the Moon and Mars

    International Nuclear Information System (INIS)

    Benes, K.

    1979-01-01

    Comparative studies of the surfaces of the terrestrial planets reveal that processes of flood basalt volcanism were common to all of them, irrespective of their stages of evolution either primitive, intermediate or progressive. On the Moon manifestations of flood basalt volcanism have been recognized in basins (maria); on the planet Mars both in basins (planitiae) and in higher topographic (continental) levels. The mare-epoch of the less developed planets led to significant changes in their relief and in the crustal structure. Examples of volcanic flows from the lunar and martian surface are introduced. Some crustal uplifts on Mars can be interpreted in terms of Van Bemmelen's undations. (Auth.)

  14. Investigating lava-substrate interactions through flow experiments with syrup, wax, and molten basalt

    Science.gov (United States)

    Rumpf, M. E.; Lev, E.

    2015-12-01

    Among the many factors influencing the complex process of lava flow emplacement, the interaction with the substrate onto which flow is emplaced plays a central role. Lava flows are rarely emplaced onto smooth or regular surfaces. For example, at Kīlauea Volcano, Hawai'i, lava flows regularly flow over solid rock, vegetation, basaltic or silica sand, and man-made materials, including asphalt and concrete. In situ studies of lava-substrate interactions are inherently difficult, and often dangerous, to carry-out, requiring the design of controllable laboratory experiments. We investigate the effects of substrate grain size, cohesion, and roughness on flow mobility and morphology through a series of flow experiments using analog materials and molten basalt. We have developed a series of experiments that allow for adjustable substrate parameters and analyze their effects on lava flow emplacement. The first set of experiments are performed at the Fluids Mechanics Laboratory at the Lamont-Doherty Earth Observatory and focus on two analog materials: polyethylene glycol (PEG), a commercially available wax, and corn syrup. The fluids were each extruded onto a series of scaled substrate beds to replicate the emplacement of lava in a natural environment. Preliminary experiments demonstrated that irregular topography, particularly topography with a height amplitude similar to that of the flow itself, can affect flow morphology, width, and velocity by acting as local barriers or culverts to the fluid. This is expected from observations of fluid flow in natural environments. A follow-up set of experiments will be conducted in Fall 2015 at the Syracuse University (SU) Lava Project Lab. In this set, we will pour molten basalt directly onto a series of substrates representing natural environments found on the Earth and other rocky bodies in the Solar System. These experiments will allow for analysis of the effects of basaltic composition and high temperatures on lava-substrate heat

  15. Precious metal enrichment at low-redox in terrestrial native Fe-bearing basalts investigated using laser-ablation ICP-MS

    Science.gov (United States)

    Howarth, Geoffrey H.; Day, James M. D.; Pernet-Fisher, John F.; Goodrich, Cyrena A.; Pearson, D. Graham; Luo, Yan; Ryabov, Viktor V.; Taylor, Lawrence A.

    2017-04-01

    Primary native Fe is a rare crystallizing phase from terrestrial basaltic magmas, requiring highly reducing conditions (fO2 abundances. Three localities are known globally where native Fe bearing mafic rocks occur: (1) Paleocene basalts of Disko Island, West Greenland; (2) a Miocene lava of the Bühl basalts, Germany; and (3) mafic intrusions associated with the Late Permian Siberian flood basalts. In this contribution, we report major- and minor-element compositions and HSE concentrations for the main alloy phases (FeNi metal and cohenite) and sulfide, for all three known global occurrences of native Fe bearing basalt. Total HSE abundances in metal grains, obtained by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), are lowest in the Bühl basalt, (∼0.05 ppm), intermediate in the Disko Island basalts (4-8 ppm), and highest the Siberian Khungtukun and Dzhaltul intrusions (10-30 ppm). These differences demonstrate that, while native Fe formation is the result of carbonaceous crustal assimilation, HSE enrichment is not ubiquitous during this process. The Siberian occurrences are characterized by Pt PGE (PPGE: Pt, Pd) enrichment relative to the Ir PGE (IPGE: Rh, Ru, Ir, Os), consistent with models of early stage fractionation of olivine, chromite and metallic IPGE in staging magma reservoirs, prior to the addition of C-rich crustal materials in the shallow crust. Relative to Noril'sk Ni-Cu-PGE sulfide ores, the Siberian native Fe basalts are enriched in the PPGE relative to the IPGE, but exhibit Ru enrichments. In contrast, Disko Island native Fe rocks do not show significant fractionation of the PPGE from the IPGE, but have positive Re and Ru anomalies and high Os/Ir ratios. To reconcile these observations, we present a general model where some parental melts experienced early-stage crustal assimilation in staging magma reservoirs, prior to reduction by carbon-rich materials (e.g., Khungtukun, Dzhaltul), whereas basaltic parental melts to

  16. Orientation-dependent electromagnetic properties of basalt fibre/nickel core–shell heterostructures

    International Nuclear Information System (INIS)

    Yu-Qing, Kang; Mao-Sheng, Cao; Xiao-Yong, Fang; Jie, Yuan

    2010-01-01

    The influence of orientation on electromagnetic properties of basalt fibre/nickel core–shell heterostructures prepared by a simple electroless plating method is investigated. For comparison, the same investigation is also performed on naked basalt fibres. For electromagnetic measurement, the directions of basalt fibre/nickel and naked basalt fibres are parallel, random and perpendicular to the direction of external electric field, termed E || sample, random sample and E p erpendicular sample, respectively. Electromagnetic anisotropy can be clearly observed in the basalt fibre/nickel core–shell heterostructures, while electromagnetic properties of naked basalt fibres are unrelated to the orientation. The E p erpendicular basalt fibre/nickel shows the highest dielectric loss but the lowest magnetic loss, and E || basalt fibre/nickel exhibits the highest magnetic loss but the lowest dielectric loss. The dielectric loss of E p erpendicular basalt fibre/nickel is several times as large as that of E || basalt fibre/nickel, which could be attributed to the increase of polarization relaxation time as a consequence of the nanosize-confinement effect. The magnetic loss of E || basalt fibre/nickel is even one order of magnitude higher than that of E p erpendicular basalt fibre/nickel, which originates mainly from the natural magnetic resonance of basalt fibre/nickel core–shell heterostructures. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

  17. Magmatic evolution of the fresh basalts from the Ridge axis near Egaria Fracture Zone, Central Indian Ridge

    Digital Repository Service at National Institute of Oceanography (India)

    Mudholkar, A.V.

    the basalts under study. These gradual changes in the olivines and plagioclase point to a simple evolution of the basaltic magma by differentiating mineral phases from the parental basalt The resorption features observed in high forsteritic olivines (~ 89...

  18. Basaltic substrate composition affects microbial community development and acts as a source of nutrients in the deep biosphere

    Science.gov (United States)

    Bailey, B.; Sudek, L.; Templeton, A.; Staudigel, H.; Tebo, B.; Moyer, C.; Davis, R.

    2006-12-01

    Studies of the oceanic crust over the past decade have revealed that in spite of the oligotrophic nature of this environment, a diverse biosphere is present in the upper 1 km of basaltic crust. The key energy source in this setting may be the high content of transistion metals (Fe, Mn) found in the basaltic glass, but in order to discover the role of Fe and Mn in the deep biosphere, we must first determine which microbes are present and how they attain the necessary metabolites for proliferation. Our work contributes to both questions through the use of molecular microbiology techniques and the exposure of specifically designed substrates on the ocean floor. Loihi Seamount off the southeast coast of the Big Island of Hawai'i provides a unique laboratory for the study of distribution and population of microbial communities associated with iron rich environments on the ocean floor. Iron oxide flocculent material (floc) dominates the direct and diffuse hydrothermal venting areas on Loihi which makes it a prime target for understanding the role of iron in biological systems in the deep biosphere. We collected iron oxide floc and basaltic glass from pillow basalts around several hydrothermal vents on the crater rim, within the pit crater Pele's Pit, and from deep off of the southern rift zone of Loihi using the HURL PISCES IV/V submersibles. We also deployed basaltic glass sand amended with various nutrients (phosphate, oxidized and reduced iron, manganese) and recovered them in subsequent years to determine how substrate composition affects community structure. We extracted DNA from both rock and iron flocs and used t-RFLP to obtain a genetic fingerprint of the microbial communities associated with each substrate. From olivine and tholeiitic basalt enrichments, it appears that substrate composition strongly influences microbial colonization and subsequent community development even when deployed in the same conditions. Culturing efforts have yielded several iron

  19. Preliminary feasibility study on storage of radioactive wastes in Columbia River basalts. Volume II

    Energy Technology Data Exchange (ETDEWEB)

    ,

    1976-11-01

    Volume II comprises four appendices: analytical data and sample locations for basalt flow type localities; Analytical data and sample locations for measured field sections in Yakima basalts; core hole lithology and analytical data; and geophysical logs. (LK)

  20. Detection of sub-basaltic sediments by a multi-parametric joint ...

    Indian Academy of Sciences (India)

    ; modelling; structure of the earth. Abstract. In many parts of the world sedimentary horizons with potential for hydrocarbon are located below flood basalt provinces.However,the presence of high velocity basaltic overburden makes delineation ...

  1. Combined Li-He isotopes in Iceland and Jan Mayen basalts and constraints on the nature of the North Atlantic mantle

    Science.gov (United States)

    Magna, T.; Wiechert, U.; Stuart, F. M.; Halliday, A. N.; Harrison, D.

    2011-02-01

    Lithium (Li) isotopes are thought to provide a powerful proxy for the recycling of crustal material, affected by low temperature alteration, through the mantle. We present Li isotope compositions for basaltic volcanic rocks from Hengill, Iceland, and Jan Mayen in order to examine possible links between ocean island volcanism and recycled oceanic crust and to address recent suggestions that mantle 3He/ 4He is also related to recycling of ancient slabs. Basaltic glasses spanning a range of chemical enrichment from the Hengill fissure system define an inverse correlation between δ 7Li (3.8-6.9‰) and 3He/ 4He (12-20 RA). The high- 3He/ 4He basalts have low δ 18O as well as excess Eu and high Nb/U, but carry no Li isotope evidence of being the product of recycling of altered slab or wedge material. In fact, there is no clear correlation between Li or He isotopes on the one hand and any of the other fingerprints of recycled slab components. The low- 3He/ 4He samples do have elevated Nb/U, Sr/Nd, positive Eu anomalies and high δ 7Li (˜6.9‰), providing evidence of a cumulate-enriched source that could be part of an ancient altered ocean floor slab. Basalts from Jan Mayen are characterized by large degrees of enrichment in incompatible trace elements typical of EM-like basalts but have homogeneous δ 7Li typical of depleted mantle (3.9-4.7‰) providing evidence for a third mantle source in the North Atlantic. It appears that oceanic basalts can display a wide range in isotope and trace element compositions associated with recycled components whilst exhibiting no sign of modern surface-altered slab or wedge material from the Li isotope composition.

  2. Late Devonian and Triassic basalts from the southern continental ...

    Indian Academy of Sciences (India)

    In Late Devonian and Early-to-Late Triassic times, the southern continental margin of the Eastern. European Platform was the site of a basaltic volcanism in the Donbas and Fore-Caucasus areas respectively. Both volcanic piles rest unconformably upon Paleoproterozoic and Late Paleozoic units respectively, and emplaced ...

  3. Mineral chemistry of Pangidi basalt flows from Andhra Pradesh

    Indian Academy of Sciences (India)

    The equilibration temperatures of clinopyroxene (1110–1190°C) and titaniferous magnetite and ilmenite coexisting mineral phases (1063–1103°C) are almost similar in lower basalt flow and it is higher for clinopyroxene (900–1110°C) when compared to titaniferous magnetite and ilmenite coexisting mineral phases ...

  4. Automated identification of basalt spectra in Clementine lunar data

    Science.gov (United States)

    Antonenko, I.; Osinski, G. R.

    2011-06-01

    The identification of fresh basalt spectra plays an important role in lunar stratigraphic studies; however, the process can be time consuming and labor intensive. Thus motivated, we developed an empirically derived algorithm for the automated identification of fresh basalt spectra from Clememtine UVVIS data. This algorithm has the following four parameters and limits: BC Ratio=3(R950-R900)/(R900-R750)0.003 and 0.1, where R750 represents the unnormalized reflectance of the 750 nm Clementine band, and so on. Algorithm results were found to be accurate to within an error of 4.5% with respect to visual classification, though olivine spectra may be under-represented. Overall, fresh basalts identified by the algorithm are consistent with expectations and previous work in the Mare Humorum area, though accuracy in other areas has not yet been tested. Great potential exists in using this algorithm for identifying craters that have excavated basalts, estimating the thickness of mare and cryptomare deposits, and other applications.

  5. Assesment of Alkali Resistance of Basalt Used as Concrete Aggregates

    Directory of Open Access Journals (Sweden)

    al-Swaidani Aref M.

    2015-11-01

    Full Text Available The objective of this paper is to report a part of an ongoing research on the influence of using crushed basalt as aggregates on one of durability-related properties of concrete (i.e. alkali-silica reaction which is the most common form of Alkali-Aggregate Reaction. Alkali resistance has been assessed through several methods specified in the American Standards. Results of petrographic examination, chemical test (ASTM C289 and accelerated mortar bar test (ASTM C1260 have particularly been reported. In addition, the weight change and compressive strength of 28 days cured concrete containing basaltic aggregates were also reported after 90 days of exposure to 10% NaOH solution. Dolomite aggregate were used in the latter test for comparison. The experimental results revealed that basaltic rocks quarried from As-Swaida’a region were suitable for production of aggregates for concrete. According to the test results, the studied basalt aggregates can be classified as innocuous with regard to alkali-silica reaction. Further, the 10% sodium hydroxide attack did not affect the compressive strength of concrete.

  6. Alteration of basaltic glasses from the Central Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Iyer, S.D.

    chemical changes are the loss of Si, Mg and Ca and a gain of Na and K whilst, Fe and Ti remained immobile. It reflects that the basaltic glasses have undergone initial to intermediate stages of palagonitisation under low temperature oxidative alterations...

  7. Petrography and petrogenesis of some Indian basaltic achondrites ...

    Indian Academy of Sciences (India)

    Notable characteristics observed in Lohawat howardite include crystallization of orthoenstatite first at a high-temperature followed by ferrosilite, pigeonite ... whereas the Johnstown diogenite crystallized from a slow cooling of a Ca-poor basaltic melt derived from cumulates formed from the magma ocean, similar to the origin ...

  8. Petrology of spinel lherzolite xenoliths in alkali basalts from Liri ...

    African Journals Online (AJOL)

    orthopyroxène (En89-91), de clinopyroxène (6,5 % d'Al2O3) et du spinelle riche Al sont présents dans les basaltes alcalins de Liri,. Sud du plateau Kapsiki, extrême nord de la "Ligne chaude du Cameroun". Les données pétrographiques.

  9. Primitive off-rift basalts from Iceland and Jan Mayen

    DEFF Research Database (Denmark)

    Debaille, Vinciane; Trønnes, Reidar G.; Brandon, Alan D.

    2009-01-01

    New measurements of Os, He, Sr and Nd isotopes, along with major and trace elements, are presented for basalts from the three volcanic flank zones in Iceland and from Jan Mayen Island. The 187Os/188Os ratios in lavas with <30 ppt Os (n = 4) are elevated compared to ratios in coexisting olivine an...

  10. Basalt Waste Isolation Project. Annual report, fiscal year 1979

    Energy Technology Data Exchange (ETDEWEB)

    1979-11-01

    This project is aimed at examining the feasibility and providing the technology to design and construct a radwaste repository in basalt formations beneath and within the Hanford Site. The project is divided into seven areas: systems integration, geosciences, hydrologic studies, engineered barriers, near-surface test facility, engineering testing, and repository engineering. This annual report summarizes key investigations in these seven areas. (DLC)

  11. Basalt Waste Isolation Project. Annual report, fiscal year 1979

    International Nuclear Information System (INIS)

    1979-11-01

    This project is aimed at examining the feasibility and providing the technology to design and construct a radwaste repository in basalt formations beneath and within the Hanford Site. The project is divided into seven areas: systems integration, geosciences, hydrologic studies, engineered barriers, near-surface test facility, engineering testing, and repository engineering. This annual report summarizes key investigations in these seven areas

  12. Late Devonian and Triassic basalts from the southern continental ...

    Indian Academy of Sciences (India)

    In Late Devonian and Early-to-Late Triassic times, the southern continental margin of the Eastern European Platform was the site of a basaltic volcanism in the Donbas and Fore-Caucasus areas respectively. Both volcanic piles rest unconformably upon Paleoproterozoic and Late Paleozoic units respectively, and emplaced ...

  13. Geochemistry of ultramafic xenoliths in Cenozoic alkali basalts from ...

    Indian Academy of Sciences (India)

    5Department of Leisure Business Management, DeLin Institute of Technology, Taipei 236, Taiwan. ∗. Corresponding author. e-mail: au4300@mail.au.edu.tw. Twelve ultramafic xenoliths in Cenozoic alkali basalts from Jiangsu province, eastern China have been analyzed for major, trace, Sr–Nd isotopic composition and ...

  14. Petrography and petrogenesis of some Indian basaltic achondrites ...

    Indian Academy of Sciences (India)

    oid 4-Vesta (Drake 2001; Barrat 2004; Barrat et al. 2003, 2010; Mittlefehldt 2005; McSween et al. 2011). This is the most abundant class of achon- drites and represents a collection of both volcanic and plutonic rocks formed from basaltic magmas. Keywords. Indian achondrites; HED clan; petrography; mineral chemistry; ...

  15. Influence of pyrolysis temperature on fracture response in SiOC based composites reinforced by basalt woven fabric

    Czech Academy of Sciences Publication Activity Database

    Chlup, Zdeněk; Černý, Martin; Strachota, Adam; Sucharda, Zbyněk; Halasová, Martina; Dlouhý, Ivo

    2014-01-01

    Roč. 34, č. 14 (2014), s. 3389-3398 ISSN 0955-2219 R&D Projects: GA ČR GAP107/12/2445; GA MŠk(CZ) ED1.1.00/02.0068 Institutional support: RVO:68081723 ; RVO:67985891 ; RVO:61389013 Keywords : Fracture behaviour * CMCs * Pyrolysis * Basalt fibre * Polysiloxane Subject RIV: JL - Materials Fatigue, Friction Mechanics; JI - Composite Materials (USMH-B); JH - Ceramics, Fire-Resistant Materials and Glass (UMCH-V) Impact factor: 2.947, year: 2014

  16. Depleted basaltic lavas from the proto-Iceland plume, Central East Greenland

    DEFF Research Database (Denmark)

    Waight, Tod Earle; Baker, Joel A.

    2012-01-01

    New geochemical and isotopic data are presented for volumetrically minor, depleted low-Ti basalts that occur in the Plateau Basalt succession of central East Greenland (CEG), formed during the initial stages of opening of the North Atlantic at 55 Ma. The basalts have MORB-like geochemistry (e.g. ...

  17. Spectroscopy of olivine basalts using FieldSpec and ASTER data: A ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Earth System Science; Volume 124; Issue 7. Spectroscopy of olivine basalts using FieldSpec and ASTER data: ... Fresh olivine basalt (group A) is characterized by low flat spectral profile with overall low reflectance values (~20%). Spectral profile of altered olivine basalt (group B) shows moderate ...

  18. Behaviour of rare earth elements, as natural analogues of transuranium elements, during weathering of basaltic glasses

    International Nuclear Information System (INIS)

    Daux, V.; Crovisier, J.L.; Petit, J.C.

    1991-01-01

    Subglacial basaltic glasses from Iceland have been studied in order to investigate REE behaviour low-temperature weathering. Just as actinides accumulate in the hydrated superficial corrosion layer of borosilicate glasses, REEs are found to be enriched in the natural corrosion layer of basaltic glasses (palagonite). However, this enrichment is only relative for basaltic glasses [fr

  19. Geochemical study of young basalts in East Azerbaijan (Northwest of Iran

    Directory of Open Access Journals (Sweden)

    Nasir Amel

    2016-12-01

    Full Text Available The young basalts in East Azerbaijan are placed in West Alborz – Azerbaijan zone. Volcanic activities have extended from the Pliocene to the Quaternary by eruption from fracture systems and faults. Rocks under study are olivine-basalt and trachybasalts. The main minerals are olivine, pyroxene, plagioclase set in glassy or microcrystalline matrix and olivine are present as phenocryst. The textures in the studied rocks are mainly hyaloporphyric, hyalomicrolitic and porphyritic. Trace elements and rare earth elements on spider diagrams have high LREE/HREE ratio. Rare earth elements on diagram display negative slope indicating alkaline nature for the basalts under study. As it may be observed, on tectonic diagrams, the Marand basalts are placed on Island Arc basalt (IAB field, whereas the Ahar, Heris, Kalaibar and Miyaneh basalts are classified as Ocean Island Basalts (OIB and finally the basalts of Sohrol area are plotted on continental rift Basalt (CRB field. The Marand and Sohrol basalts were likely originated from lithospheric - astenospheric mantle with 2 to 5 % partial melting whereas, the Ahar, Heris and Kalaibar basalts having same source experienced 1-2% partial melting rate and the Miyaneh basalts possibly produced from lithospheric mantle with 10-20% partial melting rate pointing to shallow depth of mantle and the higher rate of melting. Based on tectonic setting diagrams, all the rocks studied are plotted in post collisional environments.

  20. Architecture and emplacement of flood basalt flow fields: case studies from the Columbia River Basalt Group, NW USA

    Science.gov (United States)

    Vye-Brown, C.; Self, S.; Barry, T. L.

    2013-03-01

    The physical features and morphologies of collections of lava bodies emplaced during single eruptions (known as flow fields) can be used to understand flood basalt emplacement mechanisms. Characteristics and internal features of lava lobes and whole flow field morphologies result from the forward propagation, radial spread, and cooling of individual lobes and are used as a tool to understand the architecture of extensive flood basalt lavas. The features of three flood basalt flow fields from the Columbia River Basalt Group are presented, including the Palouse Falls flow field, a small (8,890 km2, ˜190 km3) unit by common flood basalt proportions, and visualized in three dimensions. The architecture of the Palouse Falls flow field is compared to the complex Ginkgo and more extensive Sand Hollow flow fields to investigate the degree to which simple emplacement models represent the style, as well as the spatial and temporal developments, of flow fields. Evidence from each flow field supports emplacement by inflation as the predominant mechanism producing thick lobes. Inflation enables existing lobes to transmit lava to form new lobes, thus extending the advance and spread of lava flow fields. Minimum emplacement timescales calculated for each flow field are 19.3 years for Palouse Falls, 8.3 years for Ginkgo, and 16.9 years for Sand Hollow. Simple flow fields can be traced from vent to distal areas and an emplacement sequence visualized, but those with multiple-layered lobes present a degree of complexity that make lava pathways and emplacement sequences more difficult to identify.

  1. Determination of basalt physical and thermal properties at varying temperatures, pressures, and moisture contents. First progress report, fiscal year 1979

    International Nuclear Information System (INIS)

    Miller, R.J.; Bishop, R.C.

    1979-01-01

    This report is a summary of the rock mechanics testing done at the Earth Mechanics Institute of the Colorado School of Mines for Rockwell Hanford Operations under Subcontract SA-917. Cores were supplied from drill hole DC-6 on the Hanford Site, characterized geologically, and tested for thermal and physical properties for designing long-term underground storage of radioactive waste materials. This report presents the approved test procedures, results, and data analysis for this test series. Results indicated thermophysical properties similar to those of previously tested basalt cores from the Hanford area, but showed no significant trends; thus, generalizations are risky at this time. However, density was found to be a good guide to thermal and physical properties--higher density basalt cores showed significant improvements in physical and thermal properties

  2. Thorium abundances of basalt ponds in South Pole-Aitken basin: Insights into the composition and evolution of the far side lunar mantle

    Science.gov (United States)

    Hagerty, Justin J.; Lawrence, D.J.; Hawke, B.R.

    2011-01-01

    Imbrian-aged basalt ponds, located on the floor of South Pole-Aitken (SPA) basin, are used to provide constraints on the composition and evolution of the far side lunar mantle. We use forward modeling of the Lunar Prospector Gamma Ray Spectrometer thorium data, to suggest that at least five different and distinct portions of the far side lunar mantle contain little or no thorium as of the Imbrian Period. We also use spatial correlations between local thorium enhancements and nonmare material on top of the basalt ponds to support previous assertions that lower crustal materials exposed in SPA basin have elevated thorium abundances, consistent with noritic to gabbronoritic lithologies. We suggest that the lower crust on the far side of the Moon experienced multiple intrusions of thorium-rich basaltic magmas, prior to the formation of SPA basin. The fact that many of the ponds on the lunar far side have elevated titanium abundances indicates that the far side of the Moon experienced extensive fractional crystallization that likely led to the formation of a KREEP-like component. However, because the Imbrian-aged basalts contain no signs of elevated thorium, we propose that the SPA impact event triggered the transport of a KREEP-like component from the lunar far side and concentrated it on the nearside of the Moon. Because of the correlation between basaltic ponds and basins within SPA, we suggest that Imbrian-aged basaltic volcanism on the far side of the Moon was driven by basin-induced decompressional melting.

  3. PETRO- AND PALEOMAGNETIC STUDIES OF BASALTS OF THE UPPER DEVONIAN APPAINSKAYA SUITE (WESTERN YAKUTIA

    Directory of Open Access Journals (Sweden)

    К. M. Konstantinov

    2016-01-01

    Enerdek loop to the M. Dyukteli river (outcrop 16÷20/14, only plagiophyric basalts of the lower nappe are developed. At this location, the total capacity of the basalts can reach 35–40 m. In view of the fact that the basalts lie subhorizontally at angles up to 5° (outcrop 17/14, Fig. 3, oriented samples were taken in the modern system of coordinates.Formational features of the chemical composition typical of the Middle Paleozoic intrusive basites (higher contents of Ti, Fe and K are less clear in derivatives of the effusive facies. By their chemical composition, the basalts are normal alkalinity rocks (the sum of alkali not higher than 3.05 %; SiO2=48.1–49.7 %; rather moderate content of TiO2=1.9–2.5 % (Fig. 4 A, B. The amount of magnesia (Mg# ranges from 46 to 56. The main carriers of natural remanent magnetization (NRM, In are titanomagnetites that belong to titanomagnetite and hemo-ilmenite series (Fig. 4.Research. Our research was conducted in specialized laboratories using modern equipment and facilities of Geo-Scientific Research Enterprise (NIGP PJSC ALROSA (Mirny, Institute of the Earth's Crust SB RAS (Irkutsk, Kazan Federal University (Kazan and Institute of Geology of Diamond and Precious Metals SB RAS (Yakutsk.Research results. By magnetic (scalar and vector parameters, basalts of the Appainskaya suite are characterized by the bimodal distribution of magnetic susceptibility values, NRM and æ: geometric means are 810·10–5 Si-units and 225·10–3 А/m, respectively, at the Ygyatta river, and 1470·10–5 SI-units and 490·10–3 А/m, respectively, at the Markha river (Table 1, Fig. 5. Factor Q is below 1. Results of the petrophysical observations are consistent with the geological materials and suggest that the basalts at the Ygyatta river occupy the upper stratigraphic horizon.The studied outcrops of basalts of the Appainskaya suite have the following characteristic components of Inch:1. Component А – negative vectors of the characteristic NRM

  4. Surface modification of basalt with silane coupling agent on asphalt mixture moisture damage

    Energy Technology Data Exchange (ETDEWEB)

    Min, Yahong; Fang, Ying; Huang, Xiaojun; Zhu, Yinhui; Li, Wensheng [College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082 (China); Yuan, Jianmin [College of Materials Engineering, Hunan University, Changsha, 410082 (China); Tan, Ligang [College of Mechanical and Vehicle Engineering, Hunan University, Changsha, 410082 (China); Wang, Shuangyin [State Key Laboratory of Chem/Bio-Sensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082 (China); Wu, Zhenjun, E-mail: wooawt@163.com [College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082 (China)

    2015-08-15

    Graphical abstract: - Highlights: • A new silane coupling agent was synthesized based on KH570. • Basalt surface was modified using the new silane coupling agent. • Chemical bond between basalt and the new silane coupling agent was formed. • Asphalt mixture which used modified basalt show superior water stability. - Abstract: A new silane coupling agent was synthesized based on γ-(methacryloyloxy) propyltrimethoxysilane (KH570). The surface of basalt rocks was modified by KH570 and the new silane coupling agent (NSCA), and the interfacial interaction between silane coupling agent and basalt was also studied. Fourier transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS) analysis showed that the silane coupling agent molecule bound strongly with basalt rocks. Scanning electronic microscopy (SEM) observation showed that a thin layer of coupling agent was formed on the surface of modified basalt. The boiling test and immersion Marshall test confirmed that the moisture sensitivity of basalt modified with the new silane coupling agent increased more significantly than that untreated and treated with KH570. The Retained Marshall Strength of basalt modified with the new coupling agent increased from 71.74% to 87.79% compared with untreated basalt. The results indicated that the new silane coupling agent played an important role in improving the interfacial performance between basalt and asphalt.

  5. Evidence for microbial activity at the glass-alteration interface in oceanic basalts

    Science.gov (United States)

    Torsvik, Terje; Furnes, Harald; Muehlenbachs, Karlis; Thorseth, Ingunn H.; Tumyr, Ole

    1998-10-01

    A detailed microbiological and geochemical study related to the alteration of basaltic glass of pillow lavas from the oceanic crust recovered from Hole 896A on the Costa Rica Rift (penetrating 290 m into the volcanic basement) has been carried out. A number of independent observations, pointing to the influence of microbes, may be summarized as follows: (1) Alteration textures are reminiscent of microbes in terms of form and shape. (2) Altered material contains appreciable amounts of C, N and K, and the N/C ratios are comparable to those of nitrogen-starved bacteria. (3) Samples stained with a dye (DAPI) that binds specifically to nucleic acids show the presence of DNA in the altered glass. Further, staining with fluorescent labeled oligonucleotide probes that hybridize specifically to 16S-ribosomal RNA of bacteria and archaea demonstrate their presence in the altered part of the glass. (4) Disseminated carbonate in the glassy margin of the majority of pillows shows δ 13C values, significantly lower than that of fresh basalt, also suggests biological activity. The majority of the samples have δ 18O values indicating temperatures of 20-100°C, which is in the range of mesophilic and thermophilic micro-organisms.

  6. Surface modification and characterization of basalt fibers as potential reinforcement of concretes

    Science.gov (United States)

    Iorio, M.; Santarelli, M. L.; González-Gaitano, G.; González-Benito, J.

    2018-01-01

    Basalt fibers were surface treated with silane coupling agents as a method to enhance the adhesion and durability of fiber-matrix interfaces in concrete based composite materials. In particular, this work has been focused on the study of basalt fibers chemical coatings with aminosilanes and their subsequent characterization. Surface treatments were carried out after removing the original sizing applied by manufacturer and pretreating them with an activation process of surface silanol regeneration. Different samples were considered to make convenient comparisons: as received fibers (commercial), calcinated fibers (without commercial sizing), activated samples (calcinated fibers subjected to an acid process for hydroxyl regeneration), and silanized fibers with γ-aminopropiltriethoxysilane, γ-aminopropilmethyldiethoxysilane and a mixture of 50% by weight of both silanes. A deep characterization was carried out in terms of structure using X-ray diffraction, XRD, and Fourier transform infrared spectroscopy, FTIR, thermal properties by thermogravimetric analysis, TGA, coupled with single differential thermal analysis, SDTA, and morphology by scanning electron microscopy, SEM, and atomic force microscopy, AFM.

  7. Kinetics and physico-chemical properties of alkali activated blast-furnace slag/basalt pastes

    Directory of Open Access Journals (Sweden)

    H. El Didamony

    2012-12-01

    Full Text Available Granulated blast-furnace slag (GBFS is a by-product of the metallurgical industry and consists mainly of lime and calcium–magnesium aluminosilicates that defined as the glassy granular material formed by rapid cooling of molten slag with excess water resulting in an amorphous structure. Alkali-activated slag (AAS binders have taken a great interest from researchers due to its manufacturing process which has important benefits from the point of view of the lower energy requirements and lower emission of greenhouse gases with respect to the manufacturing of Portland cement. In this study, GBFS was replaced by 20, 40 and 60 wt.% of basalt activated by 6 wt.% of alkali mixture composed of 1:1 sodium hydroxide (SH and liquid sodium silicate (LSS mixed with sea water and cured in 100% relative humidity up to 90 days. The physic-chemical parameters were studied by determination of setting time, combined water content, bulk density and compressive strength. As the amount of basalt increases the setting time as well as compressive strength decreases while the bulk density increases. The compressive strength values of dried pastes are greater than those of saturated pastes. The hydrated products are identified by TGA/DTG analysis, IR spectroscopy and scanning electron microscopy (SEM.

  8. Basalt characterization by means of nuclear and electrical well logging techniques. Case study from Southern Syria

    International Nuclear Information System (INIS)

    Asfahani, Jamal

    2011-01-01

    Nuclear well logging, including natural gamma ray, density, and neutron-porosity techniques are used with electrical well logging of long and short normal techniques to characterize the basaltic areas largely extended in Southern Syria. Statistical analysis approach with the threshold concept has been adapted for such characterization, where four kinds of basalt have been identified: very hard basalt, hard basalt, fractured basalt, and basalt alteration products. The spectrometric gamma technique has also been applied on the retrieved rock samples in order to determine the radioactive content (eU, eTh, and K%) of the basaltic section in the study area. No radioactive anomalies have been detected, the radioactive values are normal and in the expected range.

  9. Continental flood basalts derived from the hydrous mantle transition zone.

    Science.gov (United States)

    Wang, Xuan-Ce; Wilde, Simon A; Li, Qiu-Li; Yang, Ya-Nan

    2015-07-14

    It has previously been postulated that the Earth's hydrous mantle transition zone may play a key role in intraplate magmatism, but no confirmatory evidence has been reported. Here we demonstrate that hydrothermally altered subducted oceanic crust was involved in generating the late Cenozoic Chifeng continental flood basalts of East Asia. This study combines oxygen isotopes with conventional geochemistry to provide evidence for an origin in the hydrous mantle transition zone. These observations lead us to propose an alternative thermochemical model, whereby slab-triggered wet upwelling produces large volumes of melt that may rise from the hydrous mantle transition zone. This model explains the lack of pre-magmatic lithospheric extension or a hotspot track and also the arc-like signatures observed in some large-scale intracontinental magmas. Deep-Earth water cycling, linked to cold subduction, slab stagnation, wet mantle upwelling and assembly/breakup of supercontinents, can potentially account for the chemical diversity of many continental flood basalts.

  10. The solubility of olivine in basaltic liquids - An ionic model

    Science.gov (United States)

    Herzberg, C. T.

    1979-01-01

    A model is presented which enables the temperature at which olivine is in equilibrium with any alkali-depleted basaltic compound to be calculated to within + or - 30 C. It is noted that the error increases substantially when applied to terrestrial basalts which contain several weight percent alkalis. In addition the model predicts and quantifies the reduced activity of SiO4(4-) monomers due to increasing SiO2 concentrations in the melt. It is shown that the coordination of alumina in melts which precipitate olivine only appears to be dominantly octahedral, while titanium acts as a polmerizing agent by interconnecting previously isolated SiO4(4-) monomers. It is concluded that the model is sufficiently sensitive to show that there are small repulsive forces between Mg(2+) and calcium ions which are in association with normative diopside in the melt.

  11. Mineralogy and geochemistry of picro-dolerite dykes from the central Deccan Traps flood basaltic province, India, and their geodynamic significance

    Science.gov (United States)

    Dongre, Ashish; Viljoen, K. S.; Rathod, A.

    2018-04-01

    Constituent mineral compositions and whole rock major element geochemistry of picro-dolerite dykes from the central part of the Deccan flood basalt province are presented and discussed. The dykes are characterized by an MgO content of about 13 wt%, coupled with 13-16 modal percents of olivine. A high whole rock molar Mg# value of 71 and the presence of magnesian olivine phenocrysts ( Fo78) are consistent with a primitive (i.e. unevolved) geochemistry. The nature and composition of clinopyroxene (augite and pigeonite), plagioclase feldspar (labradorite) and Fe-Ti oxides (mostly ilmenite and magnetite) are also discussed, with implications drawn with respect to the geodynamics. High MgO magmas and rocks such as picrites are generally considered to be indicative of plume magmatism, formed by high degrees of partial melting in, e.g. the high-temperature region of a plume head. Recent age data is consistent with a model in which the Deccan LIP picritic magmatism is associated with the main phase of Deccan Trap activity at 66 Ma, as a result of a syn- to post rifting phase associated with the impact of the Rèunion mantle plume. It is speculated that the differentiation of primary olivine basaltic magma of picritic composition, may have been the mechanism for the generation of alkalic basalts which occurs in the Deccan Trap basaltic sequence.

  12. Supertoxic Flood Basalts: The CAMP - Siberian Trap Connection

    Science.gov (United States)

    Puffer, J. H.

    2007-12-01

    Several diverse magma types are represented throughout the CAMP and Siberian Trap LIPs, however, the main extrusive phase of each province is highly unusual among continental flood basalts. The most widespread extrusions were intermediate titanium (ITi-type) CAMP basalt and the lower portion of the Upper Sequence of Siberian Trap. New and recently published data indicate that the geochemistry and petrology of these basalt suites closely resemble each other and infer similar origins. The basalts are characterized by strong negative Nb- Ta anomalies and unusual island arc-like depletion in high field strength elements, particularly Ti, plotted on spider diagrams. The geochemical data is consistent with significant contributions from subducted slabs into the magma source regions. If contaminated, volatile enriched mantle wedges were trapped beneath thick continental plates during the assembly of Pangea, fertile magma sources would have remained dormant until decompression melting was triggered during failed rift, then early rift stages of continental plate disassembly. The combination of volatile enriched sources and highly extensional tectonism would create rare perfect storms of toxicity. Calculated low viscosities assuming negligible carbon dioxide are consistent with rapid crustal penetration. Resulting aphyric melts extruded at enormous effusive rates as thick sub-parallel flows across wide subareal terrains through fissures extending several hundred km in length. High fountain heights would afford ample opportunity for efficient degassing, perhaps into the stratosphere. When the supply of volatile flux was exhausted magmatism ceased. The mass extinctions that coincide with CAMP and Siberian volcanism contrast with some large plume and superplume events that correlate with expansions of biodiversity. This may be due in part to contrasting magma access to sources of toxic volatiles, particularly sulfur concentrations in anoxic subducted sediments.

  13. Genetic aspects of basalts from the Carlsberg Ridge

    Digital Repository Service at National Institute of Oceanography (India)

    Banerjee, R.; Iyer, S.D.

    and three decades later, other workers 5 ? 7 reported the pre s ence of ultrabasics, gab - bros, dolerites, spilites and metamorphosed effusiv es besides basalts along different segments of the CR. Isotopes and rare earth element contents of rocks..., although less dominant, usually occurs as anhedral to euhedral, skeletal and la n tern - shaped forms in the groundmass and as micro - pheno - crysts while zoned olivine is rare. The ore minerals are mainly pyrite, chalcopyrite and magnetite 17...

  14. The Age of Rift-Related Basalts in East Antarctica

    Science.gov (United States)

    Leitchenkov, G. L.; Belyatsky, B. V.; Kaminsky, V. D.

    2018-01-01

    The Lambert Rift, which is a large intracontinental rift zone in East Antarctica, developed over a long period of geological time, beginning from the Late Paleozoic, and its evolution was accompanied by magmatic activity. The latest manifestation of magmatism is eruption of alkaline olivine-leucite basalts on the western side of the Lambert Rift; Rb-Sr dating referred its time to the Middle Eocene, although its genesis remained vague. In order to solve this problem, we found geochronometer minerals in basaltic samples and 68 apatite grains appeared to be suitable for analysis. Their ages and ages of host basalts, determined by the U-Pb local method on the SIMS SHRIMP-II, were significantly different (323 ± 31 Ma) from those assumed earlier. This age corresponds to the earliest stage of crustal extension in East Antarctica and to most of Gondwana. The new data crucially change the ideas about the evolution of Lambert Rift and demonstrate the ambiguity of K-Ar dates of the alkali effusive formed under long-term rifting.

  15. Interim reclamation report, Basalt Waste Isolation project: Boreholes, 1989

    Energy Technology Data Exchange (ETDEWEB)

    Brandt, C.A.; Rickard, W.H. Jr.; Hefty, M.G.

    1990-03-01

    In 1968, a program was started to assess the feasibility of storing Hanford Site defense waste in deep caverns constructed in basalt. This program was expanded in 1976 to include investigations of the Hanford Site as a potential location for a mined commercial nuclear waste repository. An extensive site characterization program was begun to determine the feasibility of using the basalts beneath the Hanford Site for the repository. Site research focused primarily on determining the direction and speed of groundwater movement, the uniformity of basalt layers, and tectonic stability. Some 98 boreholes were sited, drilled, deepened, or modified by BWIP between 1977 and 1988 to test the geologic properties of the Site. On December 22, 1987, President Reagan signed into law the Nuclear Waste Policy Amendments Act of 1987, which effectively stopped all repository-related activities except reclamation of disturbed lands at the Hanford Site. This report describes the development of the reclamation program for the BWIP boreholes, its implementation, and preliminary estimates of its success. The goal of the reclamation program is to return sites disturbed by the repository program as nearly as practicable to their original conditions using native plant species. 48 refs., 28 figs., 14 tabs.

  16. Basalt Waste Isolation Project. Annual report, fiscal year 1980

    Energy Technology Data Exchange (ETDEWEB)

    1980-11-01

    During this fiscal year the information available in the fields of geology and hydrology of the Columbia Plateau was consolidated and two reports were issued summarizing this information. In addition, the information on engineered barriers was consolidated and a report summarizing the research to date on waste package development and design of borehole seals was prepared. The waste package studies, when combined with the hydrologic integration, revealed that even under extreme disruptive conditions, a repository in basalt with appropriately designed waste packages can serve as an excellent barrier for containment of radionuclides for the long periods of time required for waste isolation. On July 1, 1980, the first two heater tests at the Near-Surface Test Facility were started and have been successfully operated to this date. The papers on the Near-Surface Test Facility section of this report present the results of the equipment installed and the preliminary results of the testing. In October 1979, the US Department of Energy selected the joint venture of Kaiser Engineers/Parsons Brinckerhoff Quade and Douglas, Inc., to be the architect-engineer to produce a conceptual design of a repository in basalt. During the year, this design has progressed and concept selection has now been completed. This annual report presents a summary of the highlights of the work completed during fiscal year 1980. It is intended to supplement and summarize the nearly 200 papers and reports that have been distributed to date as a part of the Basalt Waste Isolation Project studies.

  17. Temperature profile around a basaltic sill intruded into wet sediments

    Science.gov (United States)

    Baker, Leslie; Bernard, Andrew; Rember, William C.; Milazzo, Moses; Dundas, Colin M.; Abramov, Oleg; Kestay, Laszlo P.

    2015-01-01

    The transfer of heat into wet sediments from magmatic intrusions or lava flows is not well constrained from field data. Such field constraints on numerical models of heat transfer could significantly improve our understanding of water–lava interactions. We use experimentally calibrated pollen darkening to measure the temperature profile around a basaltic sill emplaced into wet lakebed sediments. It is well known that, upon heating, initially transparent palynomorphs darken progressively through golden, brown, and black shades before being destroyed; however, this approach to measuring temperature has not been applied to volcanological questions. We collected sediment samples from established Miocene fossil localities at Clarkia, Idaho. Fossils in the sediments include pollen from numerous tree and shrub species. We experimentally calibrated changes in the color of Clarkia sediment pollen and used this calibration to determine sediment temperatures around a Miocene basaltic sill emplaced in the sediments. Results indicated a flat temperature profile above and below the sill, with T > 325 °C within 1 cm of the basalt-sediment contact, near 300 °C at 1–2 cm from the contact, and ~ 250 °C at 1 m from the sill contact. This profile suggests that heat transport in the sediments was hydrothermally rather than conductively controlled. This information will be used to test numerical models of heat transfer in wet sediments on Earth and Mars.

  18. H2O solubility in basalt at upper mantle conditions

    Science.gov (United States)

    Mitchell, Alexandra L.; Gaetani, Glenn A.; O'Leary, Julie A.; Hauri, Erik H.

    2017-10-01

    This study presents a new experimental approach for determining H2O solubility in basaltic melt at upper mantle conditions. Traditional solubility experiments are limited to pressures of 600 MPa or less because it is difficult to reliably quench silicate melts containing greater than 10 wt% dissolved H2O. To overcome this limitation, our approach relies on the use of secondary ion mass spectrometry to measure the concentration of H dissolved in olivine and on using the measured H in olivine as a proxy for the concentration of H2O in the co-existing basaltic melt. The solubility of H2O in the melt is determined by performing a series of experiments at a single pressure and temperature with increasing amounts of liquid H2O added to each charge. The point at which the concentration of H in the olivine first becomes independent of the amount of initial H2O content of the charge (added + adsorbed H2O) indicates its solubility in the melt. Experiments were conducted by packing basalt powder into a capsule fabricated from San Carlos olivine, which was then pressure-sealed inside a Ni outer capsule. Our experimental results indicate that at 1000 MPa and 1200 °C, the solubility of H2O in basaltic melt is 20.6 ± 0.9 wt% (2 × standard deviation). This concentration is considerably higher than predicted by most solubility models but defines a linear relationship between H2O fugacity and the square of molar H2O solubility when combined with solubility data from lower pressure experiments. Further, our solubility determination agrees with melting point depression determined experimentally by Grove et al. (2006) for the H2O-saturated peridotite solidus at 1000 MPa. Melting point depression calculations were used to estimate H2O solubility in basalt along the experimentally determined H2O-saturated peridotite solidus. The results suggest that a linear relationship between H2O fugacity and the square of molar solubility exists up to 1300 MPa, where there is an inflection point

  19. Assessing Eruption Column Height in Ancient Flood Basalt Eruptions

    Science.gov (United States)

    Glaze, Lori S.; Self, Stephen; Schmidt, Anja; Hunter, Stephen J.

    2015-01-01

    A buoyant plume model is used to explore the ability of flood basalt eruptions to inject climate-relevant gases into the stratosphere. An example from the 1986 Izu-Oshima basaltic fissure eruption validates the model's ability to reproduce the observed maximum plume heights of 12-16 km above sea level, sustained above fire-fountains. The model predicts maximum plume heights of 13-17 km for source widths of between 4-16 m when 32% (by mass) of the erupted magma is fragmented and involved in the buoyant plume (effective volatile content of 6 wt%). Assuming that the Miocene-age Roza eruption (part of the Columbia River Basalt Group) sustained fire-fountains of similar height to Izu-Oshima (1.6 km above the vent), we show that the Roza eruption could have sustained buoyant ash and gas plumes that extended into the stratosphere at approximately 45 deg N. Assuming 5 km long active fissure segments and 9000 Mt of SO2 released during explosive phases over a 10-15 year duration, the approximately 180 km of known Roza fissure length could have supported approximately 36 explosive events/phases, each with a duration of 3-4 days. Each 5 km fissure segment could have emitted 62 Mt of SO2 per day into the stratosphere while actively fountaining, the equivalent of about three 1991 Mount Pinatubo eruptions per day. Each fissure segment could have had one to several vents, which subsequently produced lava without significant fountaining for a longer period within the decades-long eruption. Sensitivity of plume rise height to ancient atmospheric conditions is explored. Although eruptions in the Deccan Traps (approximately 66 Ma) may have generated buoyant plumes that rose to altitudes in excess of 18 km, they may not have reached the stratosphere because the tropopause was substantially higher in the late Cretaceous. Our results indicate that some flood basalt eruptions, such as Roza, were capable of repeatedly injecting large masses of SO2 into the stratosphere. Thus sustained

  20. A combined analysis of basaltic melting and shear wave velocity anomalies to constrain dynamic support of western North America

    Science.gov (United States)

    Klöcking, Marthe; White, Nicky; Maclennan, John; Fitton, Godfrey

    2017-04-01

    The region of western North America that encompasses the Basin and Range Province, the Snake River Plain and the Colorado Plateau is about 2 km higher than cratonic North America. This topographic difference broadly coincides with variations in lithospheric thickness (i.e. Mexico, and inverse modeling of regional drainage networks together suggest that this regional uplift occurred during Cenozoic time in at least two discrete phases. Earthquake tomographic models have imaged low velocity material beneath the bulk of western North America, including a ring-shaped anomaly encompassing the Colorado Plateau itself. Basaltic magmatism coincides with these low velocity zones and indicates an overall increase in melt volume at 40 Ma, as well as an abrupt change from lithospheric to asthenospheric signatures at 5 Ma. To investigate the quantitative relationship between seismic velocity anomalies and basaltic magmatism, we have analyzed >260 samples from volcanic centers throughout western North America for major, trace and rare earth elements using ICP-MS and XRF techniques. For asthenospheric samples, we observe a correlation between slow shear wave velocity anomalies and basaltic geochemistry. Using a combination of petrologic observations, forward and inverse modeling of major and rare earth elements, and shear wave velocity anomalies from tomographic models, we determine depth of melting and melt fraction. We explore the possibility that volatiles, anomalous source composition and/or temperature can give rise to basaltic magmatism and regional uplift. We then calculate mantle temperatures from shear wave velocity profiles beneath each volcanic field. In this way, we exploit a variety of approaches to constrain lithospheric thickness and mantle potential temperature. Our combined geochemical and geophysical results yield excess temperatures of 50-80 °C beneath a 60 km thin lithospheric plate. A dynamic topographic model of progressive lithospheric erosion over

  1. Genomic evidence for the Wood-Ljungdahl pathway for carbon fixation in warm basaltic ocean crust

    Science.gov (United States)

    Smith, A. R.; Fisk, M. R.; Mueller, R.; Colwell, F. S.; Mason, O. U.; Popa, R.

    2016-12-01

    Microbial life in the deep suboceanic aquifer can harness geochemical energy resulting from water-rock reactions and contribute to carbon cycling in the ocean via primary production, or chemosynthesis. Iron-bearing minerals such as olivine in oceanic crust can produce molecular hydrogen, small molecular weight hydrocarbons, and hydrogen sulfide as they react with seawater. Although this generally occurs in serpentinizing systems at very high temperatures deep in the subsurface, it has also been hypothesized to drive the subseafloor microbial ecosystems present in shallower basaltic aquifers. We present genome-based evidence for chemolithoautotrophic microbes present on the surface of olivine incubated in Juan de Fuca Ridge basaltic ocean crust for a 4-year period. These metagenome-derived genomes show dominant taxa capable of using both branches of the Wood-Ljungdahl pathway for carbon fixation and energy generation. This pathway uses molecular hydrogen potentially derived from the olivine surface as it reacts with seawater and CO2 which is inherent to seawater. These taxa were not reported from aquifer fluid samples, but have been found only in association with mineral surfaces in this study location. Most taxa in this simple community are distant relatives of cultured taxa; therefore this genome information is crucial to understanding how the subseafloor aquifer community is structured, how it obtains energy, how it cycles carbon, and gives us keys to help cultivate these organisms in the laboratory. Our findings also support the Subsurface Lithoautotrophic Microbial Ecosystem (SLiME) hypothesis and have implications for understanding life on early Earth and the potential for life in the Martian subsurface.

  2. Transient processes in Stromboli's shallow basaltic system inferred from dolerite and magmatic breccia blocks erupted during the 5 April 2003 paroxysm

    Science.gov (United States)

    Renzulli, Alberto; Del Moro, Stefano; Menna, Michele; Landi, Patrizia; Piermattei, Marco

    2009-09-01

    We describe the mineralogy, geochemistry, and mesomicrostructure of fresh subvolcanic blocks erupted during the 5 April 2003 paroxysm of Stromboli (Aeolian Islands, Italy). These blocks represent ˜50 vol.% of the total erupted ejecta and consist of fine- to medium-grained basaltic lithotypes ranging from relatively homogeneous dolerites to strongly or poorly welded magmatic breccias. The breccia components are represented by angular fragments of dolerites entrapped in a matrix of vesiculated (lava-like to scoriae) crystal-rich (CR) basalt. All of the studied blocks are cognates with the CR basalt of the normal Strombolian activity or lavas and they are often coated by a few-centimeter thick layer of crystal-poor (CP) basaltic pumice erupted during the paroxysm. We suggest that they result from the rapid increase of pressure and related subvolcanic rock failure that occurred shortly before the 5 April 2003 explosion, when the uppermost portion of the edifice inflated and suffered brecciation as the result of the sudden rise of the gas-rich CP basalt that triggered the eruption. Dolerites and magmatic matrix of the breccias show major and trace element compositions that match those of the CR basalts erupted during normal Strombolian activity and effusive events at Stromboli volcano. Dolerites consist of (a) phenocrysts normally found in the CR basalts and (b) late-stage magmatic minerals such as sanidine, An60-28 plagioclase, Fe-Mn-rich olivines (Fo68-48), phlogopite, apatite, and opaque mineral pairs (magnetite and ilmenite), most of which are never found both in lava flows and scoriae erupted during the persistent explosive activity that characterizes typical Strombolian behavior. Subvolcanic crystallization of the Stromboli CR magma, leading to slowly cooled equivalents of basalts, could result from transient drainage of the magma from the summit craters to lower levels. Fingering and engulfing of the material that collapsed from the summit crater floor into the

  3. Practical implications of the relation between the clay mineral content and the plasticity index of dolerite road construction material

    CSIR Research Space (South Africa)

    Kleyn, E

    2009-04-01

    Full Text Available Naturally occurring road building materials, suitable for the higher-quality upper strata of road pavements (base and subbase layers), are systematically being depleted, resulting in the haulage of alternative material over increasing distances...

  4. Proceedings of a specialists' meeting on application of the concepts of exclusion, exemption and clearance: Implications for the management of radioactive materials. Working material

    International Nuclear Information System (INIS)

    1997-01-01

    The international principles developed to help in the regulation and deregulation of low-activity materials require elaboration, and there is a need for guidance regarding their practical application. The objectives of the meeting, organized by the Agency were: To provide a forum in which concerns and issues concerned with the regulatory management of materials containing very low levels of radioactivity can be discussed; to develop strategies for resolving the issues through international action; to develop advice for Agency work in drafting guidance material for safety standards

  5. Breaking of macroscopic centric symmetry in paraelectric phases of ferroelectric materials and implications for flexoelectricity

    OpenAIRE

    Biancoli, Alberto; Fancher, Chris M.; Jones, Jacob L.; Damjanovic, Dragan

    2015-01-01

    A centrosymmetric stress cannot induce a polar response in centric materials, piezoelectricity is, for example, possible only in non-centrosymmetric structures. An exception is meta-materials with shape asymmetry, which may be polarized by stress even when the material is centric. In this case the mechanism is flexoelectricity, which relates polarization to a strain gradient. The flexoelectric response scales inversely with size, thus a large effect is expected in nanoscale materials. Recent ...

  6. Thermal Emission Spectra of Silica-coated Basalt and Considerations for Martian Surface Mineralogy

    Science.gov (United States)

    Kraft, M. D.; Sharp, T. G.; Michalski, J. R.

    2003-01-01

    Among the most important discoveries made during the Mars Global Surveyor (MGS) mission was that the rocky materials of Mars are broadly divisible into two distinct rock types. The geological significance of this finding is dependent on the mineralogy of these rock types as well as their geographic and stratigraphic positions. Much work has yet to be done to understand these relationships and the small-scale variability of these units. For now, it is worth considering various scenarios that could have resulted in Mars global-scale mineralogical dichotomy. Such work will make clearer what must be looked for in Thermal Emission Spectrometer (TES) and Thermal Imaging Spectrometer (THEMIS) data, what to test with other data sets, and what geological processes can be considered or ruled out as we advance with interpreting Martian geologic history. Here, we suggest that exogenic coatings of secondary silica on basaltic rocks may provide a plausible explanation for the newly discovered distribution of rock types.

  7. EVALUATION OF EFFECTIVE PROPERTIES OF BASALT TEXTILE REINFORCED CERAMIC MATRIX COMPOSITES

    Directory of Open Access Journals (Sweden)

    Soňa Valentová

    2017-11-01

    Full Text Available The present paper is concerned with the analysis of a ceramic matrix composite, more specifically the plain weave textile fabric composite made of basalt fibers embedded into the pyrolyzed polysiloxane matrix. Attention is paid to the determination of effective elastic properties of the yarn via homogenization based on the Mori-Tanaka averaging scheme and the 1st order numerical homogenization method adopting a suitable representative computational model. The latter approach is then employed to simulate the response of the yarn when loaded beyond the elastic limits. The required mechanical properties of individual material phases are directly measured using nanoindentation with in-build scanning probe microscopy. Applicability of the proposed computational methodology is supported by the analysis of a unidirectional fibrous composite, representing the yarn, subjected to a macroscopically uniform strain.

  8. Dynamics of melting beneath a small-scale basaltic system: a U-Th-Ra study from Rangitoto volcano, Auckland volcanic field, New Zealand

    Science.gov (United States)

    McGee, Lucy E.; Beier, Christoph; Smith, Ian E. M.; Turner, Simon P.

    2011-09-01

    The Auckland volcanic field is a Quaternary monogenetic basaltic field of 50 volcanoes. Rangitoto is the most recent of these at ~500 year BP and may mark a change in the behaviour of the field as it is the largest by an order of magnitude and is unusual in that it erupted magmas of alkalic then subalkalic basaltic composition in discrete events separated by ≤50 years. Major and trace element geochemistry together with Sr-Nd and U-Th-Ra isotopes provides the basis for modelling the melting conditions that brought about the eruption of two chemically different lavas with very little spatial or temporal change. Sr-Nd isotopes suggest that the source for both eruptions is similar with a slight degree of heterogeneity. The basalts show high 230Th-excess compared with comparable continental volcanic fields. We show that the alkalic basalts give evidence for lower degrees of partial melting, higher amounts of residual garnet, a longer melting column and lower melting and upwelling rates compared with the subalkalic basalts. The low upwelling rates (0.1-1.5 cm/year) modelled for both magmas do not suggest a plume or major upwelling in the mantle region beneath Auckland; therefore, we suggest localised convection due to relict movement from the active subduction system situated 400 km to the southeast. A higher porosity for the initial alkalic basalt is based on 226Ra-excesses, suggesting movement of melt by two different porosities: the initial melt travelling in fast high porosity channels from greater depths preserving a high 230Th-excess and the subsequent subalkalic magma travelling from a shallower depth through lower porosity diffuse channels preserving a high 226Ra-excess; this creates a negative array in (226Ra/230Th) versus (230Th/238U) space previously only seen in mid ocean ridge Basalt data. This mechanism suggests the Auckland volcanic field may operate by the presence of discrete melt batches that are able to move at different depths and speeds giving the

  9. Methods of simulating low redox potential (Eh) for a basalt repository

    International Nuclear Information System (INIS)

    Jantzen, C.M.

    1983-01-01

    Basalt groundwaters have inherently low redox potentials, approximately -0.4V, which can be measured with platinum electrodes, but are difficult to reproduce during leaching experiments. In the presence of deionized water, crushed basalt reaches the measured Eh-pH values of a basalt repository. Other waste package components, such as iron, will interact with groundwater in different ways under oxic or anoxic conditions since the presence of any redox active solid will affect the groundwater Eh. 26 references, 4 figures

  10. Petrology of basalt and single-mineral fragments in the soil of the Sea of Fertility

    Science.gov (United States)

    Bence, A. E.; Holzwarth, W.; Papike, J. J.

    1974-01-01

    Basalt and single-mineral particles, ranging from 150 to 425 microns, from the Luna-16 sample are studied by electron microanalysis, X-ray fluorescence analysis, and petrographic techniques. Three basalt species of different structure are identified. The structure and composition of the individual minerals (in particular of pyroxenes) indicate that the basalts have crystallized under conditions similar to those established for Apollo-11 samples.

  11. Engineered barrier development for a nuclear waste repository in basalt: an integration of current knowledge

    International Nuclear Information System (INIS)

    Smith, M.J.

    1980-05-01

    This document represents a compilation of data and interpretive studies conducted as part of the engineered barriers program of the Basalt Waste Isolation Project. The overall objective of these studies is to provide information on barrier system designs, emplacement and isolation techniques, and chemical reactions expected in a nuclear waste repository located in the basalts underlying the Hanford Site within the state of Washington. Backfills, waste-basalt interactions, sorption, borehole plugging, etc., are among the topics discussed

  12. Engineered barrier development for a nuclear waste repository in basalt: an integration of current knowledge

    Energy Technology Data Exchange (ETDEWEB)

    Smith, M.J.

    1980-05-01

    This document represents a compilation of data and interpretive studies conducted as part of the engineered barriers program of the Basalt Waste Isolation Project. The overall objective of these studies is to provide information on barrier system designs, emplacement and isolation techniques, and chemical reactions expected in a nuclear waste repository located in the basalts underlying the Hanford Site within the state of Washington. Backfills, waste-basalt interactions, sorption, borehole plugging, etc., are among the topics discussed.

  13. Nuclear waste repository in basalt: preconceptual design guidelines

    Energy Technology Data Exchange (ETDEWEB)

    1979-06-01

    The development of the basalt waste isolation program parallels the growing need for permanent, environmentally safe, and secure means to store nuclear wastes. The repository will be located within the Columbia Plateau basalt formations where these ends can be met and radiological waste can be stored. These wastes will be stored such that the wastes may be retrieved from storage for a period after placement. After the retrieval period, the storage locations will be prepared for terminal storage. The terminal storage requirements will include decommissioning provisions. The facility boundaries will encompass no more than several square miles of land which will be above a subsurface area where the geologic makeup is primarily deep basaltic rock. The repository will receive, from an encapsulation site(s), nuclear waste in the form of canisters (not more than 18.5 feet x 16 inches in diameter) and containers (55-gallon drums). Canisters will contain spent fuel (after an interim 5-year storage period), solidified high-level wastes (HLW), or intermediate-level wastes (ILW). The containers (drums) will package the low-level transuranic wastes (LL-TRU). The storage capacity of the repository will be expanded in a time-phased program which will require that subsurface development (repository expansion) be conducted concurrently with waste storage operations. The repository will be designed to store the nuclear waste generated within the predictable future and to allow for reasonable expansion. The development and assurance of safe waste isolation is of paramount importance. All activities will be dedicated to the protection of public health and the environment. The repository will be licensed by the US Nuclear Regulatory Commission (NRC). Extensive efforts will be made to assure selection of a suitable site which will provide adequate isolation.

  14. Nuclear waste repository in basalt: preconceptual design guidelines

    International Nuclear Information System (INIS)

    1979-06-01

    The development of the basalt waste isolation program parallels the growing need for permanent, environmentally safe, and secure means to store nuclear wastes. The repository will be located within the Columbia Plateau basalt formations where these ends can be met and radiological waste can be stored. These wastes will be stored such that the wastes may be retrieved from storage for a period after placement. After the retrieval period, the storage locations will be prepared for terminal storage. The terminal storage requirements will include decommissioning provisions. The facility boundaries will encompass no more than several square miles of land which will be above a subsurface area where the geologic makeup is primarily deep basaltic rock. The repository will receive, from an encapsulation site(s), nuclear waste in the form of canisters (not more than 18.5 feet x 16 inches in diameter) and containers (55-gallon drums). Canisters will contain spent fuel (after an interim 5-year storage period), solidified high-level wastes (HLW), or intermediate-level wastes (ILW). The containers (drums) will package the low-level transuranic wastes (LL-TRU). The storage capacity of the repository will be expanded in a time-phased program which will require that subsurface development (repository expansion) be conducted concurrently with waste storage operations. The repository will be designed to store the nuclear waste generated within the predictable future and to allow for reasonable expansion. The development and assurance of safe waste isolation is of paramount importance. All activities will be dedicated to the protection of public health and the environment. The repository will be licensed by the US Nuclear Regulatory Commission (NRC). Extensive efforts will be made to assure selection of a suitable site which will provide adequate isolation

  15. Central sorting and recovery of MSW recyclable materials: A review of technological state-of-the-art, cases, practice and implications for materials recycling

    DEFF Research Database (Denmark)

    Cimpan, Ciprian; Maul, Anja; Jansen, Michael

    2015-01-01

    Today's waste regulation in the EU comprises stringent material recovery targets and calls for comprehensive programs in order to achieve them. A similar movement is seen in the US where more and more states and communities commit to high diversion rates from landfills. The present paper reviews...... scientific literature, case studies and results from pilot projects, on the topic of central sorting of recyclable materials commonly found in waste from households. The study contributes, inter alia, with background understanding on the development of materials recovery, both in a historical...... and process control, which are targeted at curtailing process inefficiencies shown by operational practice. Technology developed for the sorting of commingled recyclables from separate collection is also being successfully used to upgrade residual MSW processing plants. The strongest motivation for central...

  16. Implications of high renewable electricity penetration in the U.S. for water use, greenhouse gas emissions, land-use, and materials supply

    International Nuclear Information System (INIS)

    Arent, Doug; Pless, Jacquelyn; Mai, Trieu; Wiser, Ryan; Hand, Maureen; Baldwin, Sam; Heath, Garvin; Macknick, Jordan; Bazilian, Morgan; Schlosser, Adam; Denholm, Paul

    2014-01-01

    Highlights: • Renewable electricity generation could supply 80% of U.S. generation in 2050. • GHGs are reduced proportionally and water use is reduced by 50%. • Gross land-use impacts total less than 3% of land area of the contiguous U.S. • Some clean energy technologies rely on materials that face short-term risks. • No insurmountable long-term constraints to materials supply were identified. - Abstract: Recent work found that renewable energy could supply 80% of electricity demand in the contiguous United States in 2050 at the hourly level. This paper explores some of the implications of achieving such high levels of renewable electricity for supply chains and the environment in scenarios with renewable supply up to such levels. Expanding the renewable electricity supply at this scale by 2050 implies annual capacity additions of roughly 20 gigawatts per year (GW/year) over the next decade, rising to roughly 40 GW/year from 2040 to 2050. Given total 2012 renewable electricity capacity additions of slightly more than 16 GW, this suggests moderate growth of the related supply chains, averaging overall roughly 4% annual growth to 2040. Transitioning to high renewable electricity supply would lead to significant reductions in greenhouse gas emissions and water use, with only modest land-use implications. While renewable energy expansion implies moderate growth of the renewable electricity supply chains, no insurmountable long-term constraints to renewable electricity technology manufacturing capacity or materials supply are identified

  17. Breaking of macroscopic centric symmetry in paraelectric phases of ferroelectric materials and implications for flexoelectricity.

    Science.gov (United States)

    Biancoli, Alberto; Fancher, Chris M; Jones, Jacob L; Damjanovic, Dragan

    2015-02-01

    A centrosymmetric stress cannot induce a polar response in centric materials; piezoelectricity is, for example, possible only in non-centrosymmetric structures. An exception is metamaterials with shape asymmetry, which may be polarized by stress even when the material is centric. In this case the mechanism is flexoelectricity, which relates polarization to a strain gradient. The flexoelectric response scales inversely with size, thus a large effect is expected in nanoscale materials. Recent experiments in polycrystalline, centrosymmetric perovskites (for example, (Ba, Sr)TiO3) have indicated values of flexoelectric coefficients that are orders of magnitude higher than theoretically predicted, promising practical applications based on bulk materials. We show that materials with unexpectedly large flexoelectric response exhibit breaking of the macroscopic centric symmetry through inhomogeneity induced by the high-temperature processing. The emerging electro-mechanical coupling is significant and may help to resolve the controversy surrounding the large apparent flexoelectric coefficients in this class of materials.

  18. Reclamation report, Basalt Waste Isolation Project, boreholes 1990

    Energy Technology Data Exchange (ETDEWEB)

    Brandt, C.A.; Rickard, W.H. Jr.; Cadoret, N.A.

    1991-01-01

    The restoration of areas disturbed activities of the Basalt Waste Isolation Project (BWIP) has been undertaken by the US Department of Energy (DOE) in fulfillment of obligations and commitments made under the National Environmental Policy Act and the Nuclear Waste Policy Act. This restoration program comprises three separate projects: borehole reclamation, Near Surface Test Facility reclamation, and Exploratory Shaft Facility reclamation. Detailed descriptions of these reclamation projects may be found in a number of previous reports. This report describes the second phase of the reclamation program for the BWIP boreholes and analyzes its success relative to the reclamation objective. 6 refs., 14 figs., 13 tabs.

  19. Friction Joint Between Basalt-Reinforced Composite and Aluminum

    DEFF Research Database (Denmark)

    Costache, Andrei; Glejbøl, Kristian; Sivebæk, Ion Marius

    2015-01-01

    The purpose of this study was to anchor basalt-reinforced polymers in an aluminum grip using dry friction. Dry friction clamping is considered the optimal solution for post-mounting of load-bearing terminations on composite structures. A new test method is presented for characterizing...... the frictional load transfer behavior of the grip. To carry out the study, a custom-built test rig was used to examine the relation between pullout force and clamping force. The anchoring method was found to be successful. The paper presents details on the custom-built test rig, along with the use of digital...

  20. Final Reclamation Report: Basalt Waste Isolation Project exploratory shaft site

    Energy Technology Data Exchange (ETDEWEB)

    Brandt, C.A.; Rickard, W.H. Jr.

    1990-06-01

    The restoration of areas disturbed by activities of the Basalt Waste Isolation Project (BWIP) constitutes a unique operation at the US Department of Energy's (DOE) Hanford Site, both from the standpoint of restoration objectives and the time frame for accomplishing these objectives. The BWIP reclamation program comprises three separate projects: borehole reclamation, Near Surface Test Facility (NSTF) reclamation, and Exploratory Shaft Facility (ESF) reclamation. The main focus of this report is on determining the success of the revegetation effort 1 year after work was completed. This report also provides a brief overview of the ESF reclamation program. 21 refs., 7 figs., 14 tabs.

  1. Sentinel Gap basalt reacted in a temperature gradient

    International Nuclear Information System (INIS)

    Charles, R.W.; Bayhurst, G.K.

    1982-01-01

    Six basalt prisms were reacted in a controlled temperature gradient hydrothermal circulation system for two months. The prisms are centered at 72, 119, 161, 209, 270, and 310 0 C. Total pressure is 1/3 kbar. All prisms show large weight loss: 5.5% to 14.9%. The matrix micropegmatite and natural nontronitic alteration readily reacts to clays at all temperatures. The first four prisms are coated with a Ca-smectite while the last two prisms are covered with discrete patches of K rich phengite and alkali feldspar. The clays may act as adsorbers of various ions

  2. Hydrologic bibliography of the Columbia River basalts in Washington

    International Nuclear Information System (INIS)

    Tanaka, H.H.; Wildrick, L.

    1978-07-01

    This bibliography is part of the hydrologic data compilation effort of the Columbia Plateau Hydrology Study, Rockwell Hanford Operations' Waste Isolation Program. It includes references on both surface and subsurface hydrology directly or indirectly related to the Washington State portion of the Columbia River basalts. A comprehensive, annotated bibliography of the Pasco Basin (including the Hanford site) hydrology has been prepared for Rockwell Hanford Operations under the Pasco Basin Hydrology Study. In order to avoid unnecessary duplication, no effort was made to include a complete list of bibliographic references on Hanford in this volume

  3. Geochemical characterization of oceanic basalts using artificial neural network

    Digital Repository Service at National Institute of Oceanography (India)

    Das, P.; Iyer, S.D.

    discrete geochemical traits of the OFB by using certain characteristic elemental concentration of these basalts. In order to classify the OFB we considered one major oxide (K 2 O),seventrace(Sc,Rb,Sr,Y,Zr,Nband Ba,),sixrareearthelements(REE)(La...,Ce,Nd,Sm,Eu, and Yb) and seven elemental ratios (Zr/Nb, Y/Nb, Ba/ Nb, Zr/Y, Sm/Nd, La/Yb and Ce/Y). A reason for utilizing the above mentioned elements and their ratios is because these carry the geochemical signatures of the individual OFB type i.e., N-MORB, E...

  4. Basalt fiber manufacturing technology and the possibility of its use in dentistry

    Science.gov (United States)

    Karavaeva, E.; Rogozhnikov, A.; Nikitin, V.; Cherepennikov, Yu; Lysakov, A.

    2015-11-01

    The article touches upon the technology of basalt fiber manufacturing and prospects of its use in dental practice. Two kinds of construction using basalt fiber have been proposed. The first one is a splinting construction for mobile teeth and the second one is the reinforced base for removable plate-denture. The work presents the results of the investigation of physical and mechanical properties of the constructions based on basalt fiber. It also describes the aspects of biomechanical modeling of such constructions in the ANSYS software package. The results of the investigation have proved that applying constructions using basalt fiber is highly promising for prosthetic dentistry practice.

  5. Sub-basalt imaging problems and the application of Artificial Neural Networks

    Science.gov (United States)

    Fitzgerald, Elaine M.; Bean, Christopher J.

    2001-12-01

    In many areas of the world, the presence of shallow high velocity, highly heterogeneous layers complicate seismic imaging of deeper reflectors. Of particular economic interest are areas where potentially hydrocarbon-bearing strata are obscured by layers of basalt. Basalt layers are highly reflective and heterogeneous. Using reflection seismic, top basalt is typified by a high-amplitude, coherent reflector with poor resolution of reflectors below the basalt, and even bottom basalt. Here, we present a new approach to the imaging problem using the pattern recognition abilities of a back-propagation Artificial Neural Network (ANN). ANNs are computational systems that attempt to mimic natural biological neural networks. They have the ability to recognize patterns and develop their own generalizations about a given data set. Back-propagation neural networks are trained on data sets for which the solution is known and tested on the data that are not previously presented to the ANN in order to validate the network result. We show that Artificial Neural Networks, due to their pattern recognition capabilities, can invert the medium statistics based on the seismic character. We produce statistically defined models involving a basalt analogous layer, and calculate full wavefield finite difference synthetic seismograms. We vary basalt layer thickness and source frequency to generate a synthetic model that produces seismic that is similar to real sub-basalt seismic, i.e. high amplitude top basalt reflector and the absence of base basalt and sub-basalt events. Using synthetic shot gathers, generated in a synthetic representation of the sub-basalt case, we can invert the velocity medium standard deviation by using an ANN. By inverting the velocity medium standard deviation, we successfully identified the transition from basalt to sub-basalt on the synthetic shot gathers. We also show that ANNs are capable of identifying the basalt to sub-basalt transition in the presence of

  6. Basalt Fiber for Volcanic Slag Lightweight Aggregate Concrete Research on the Impact of Performance

    Science.gov (United States)

    Xiao, Li-guang; Li, Gen-zhuang

    2018-03-01

    In order to study the effect of basalt fiber on the mechanical properties and durability of volcanic slag lightweight aggregate concrete, the experimental study on the flexural strength, compressive strength and freeze-thaw resistance of volcanic slag concrete with different basalt fiber content were carried out, the basalt fiber was surface treated with NaOH and water glass, the results show that the surface treatment of basalt fiber can significantly improve the mechanical properties, durability and other properties of volcanic slag lightweight aggregate concrete.

  7. Rb-Sr and Sm-Nd chronology and genealogy of mare basalts from the Sea of Tranquility

    Science.gov (United States)

    Papanastassiou, D. A.; Depaolo, D. J.; Wasserburg, G. J.

    1977-01-01

    Rb-Sr and Sm-Nd ages of two Apollo 11 mare basalts, high-K basalt 10072 and low-K basalt 10062, are reported. Rb-Sr, Sm-Nd, and Ar-40-Ar-39 ages are in good agreement and indicate an extensive time interval for filling of the Sea of Tranquility, presumably by thin lava flows, in agreement with similar observations for the Ocean of Storms. Initial Sr and Nd isotopic compositions on Apollo 11 basalts reveal at least two parent sources producing basalts. The Sm-Nd isotopic data demonstrate that low-K and high-Ti basalts from Apollo 11 and 17 derived from distinct reservoirs, while low-Ti Apollo 15 mare basalt sources have Sm/Nd similar to the sources of Apollo 11 basalts. Groupings of mare basalt based on Ti content and on isotopic data do not coincide.

  8. Basalt features observed in outcrops, cores, borehole video imagery and geophysical logs, and basalt hydrogeologic study at the Idaho National Engineering Laboratory, Eastern Idaho

    Energy Technology Data Exchange (ETDEWEB)

    Bennecke, William M. [Boise State Univ., ID (United States)

    1996-10-01

    A study was undertaken to examine permeable zones identified in boreholes open to the underlying basalt and to describe the vertical cross flows present in the boreholes. To understand the permeable zones in the boreholes detailed descriptions and measurements of three outcrops in the Snake River Plain, three cores at the Idaho Chemical Processing Plant (ICPP) at the INEL, and over fifty borehole TV logs from the INEL were carried out. Based on the observations made on the three outcrops an idealized basalt lava flow model was generated that used a set of nomenclature that would be standard for the basalt lava flows studied. An upper vesicular zone, a sometimes absent columnar zone, central zone, and lower vesicular zone make up the basalt lava flow model. The overall distinction between the different zones are based on the vesicle shape size, vesicularity, and fractures present. The results of the studies also indicated that the basalt lava flows at the INEL are distal to medial facies pahoehoe lava flows with close fitting contacts. The most permeable zones identified in these basalts are fractured vesiculated portions of the top of the lava flow, the columnar areas, and basalt-flow contacts in order of importance. This was determined from impeller flowmeter logging at the INEL. Having this information a detailed stratigraphy of individual basalt lava flows and the corresponding permeable units were generated. From this it was concluded that groundwater flow at the ICPP prefers to travel along thin basalt lava flows or flow-units. Flow direction and velocity of intrawell flows detected by flowmeter is controlled by a nearby pumping well.

  9. Basalt features observed in outcrops, cores, borehole video imagery and geophysical logs, and basalt hydrogeologic study at the Idaho National Engineering Laboratory, Eastern Idaho

    International Nuclear Information System (INIS)

    Bennecke, W.M.

    1996-10-01

    A study was undertaken to examine permeable zones identified in boreholes open to the underlying basalt and to describe the vertical cross flows present in the boreholes. To understand the permeable zones in the boreholes detailed descriptions and measurements of three outcrops in the Snake River Plain, three cores at the Idaho Chemical Processing Plant (ICPP) at the INEL, and over fifty borehole TV logs from the INEL were carried out. Based on the observations made on the three outcrops an idealized basalt lava flow model was generated that used a set of nomenclature that would be standard for the basalt lava flows studied. An upper vesicular zone, a sometimes absent columnar zone, central zone, and lower vesicular zone make up the basalt lava flow model. The overall distinction between the different zones are based on the vesicle shape size, vesicularity, and fractures present. The results of the studies also indicated that the basalt lava flows at the INEL are distal to medial facies pahoehoe lava flows with close fitting contacts. The most permeable zones identified in these basalts are fractured vesiculated portions of the top of the lava flow, the columnar areas, and basalt-flow contacts in order of importance. This was determined from impeller flowmeter logging at the INEL. Having this information a detailed stratigraphy of individual basalt lava flows and the corresponding permeable units were generated. From this it was concluded that groundwater flow at the ICPP prefers to travel along thin basalt lava flows or flow-units. Flow direction and velocity of intrawell flows detected by flowmeter is controlled by a nearby pumping well

  10. Specific features of basalts from the western part of Andrew Bain Fault, Southwest Indian Ridge

    Science.gov (United States)

    Peyve, A. A.; Skolotnev, S. G.

    2017-12-01

    This paper reports original data on the composition of volcanic rocks in the western part of the Andrew Bain Fault of the South-West Indian Ridge obtained in the 23rd voyage of R/V Akademik Nikolai Strakhov. In accordance with high La/Th and low Nb/U ratios, the basalt compositions of stations S2317, S2318, and S2330 could result from melting of the DM-type source with HIMU traces. Meanwhile, the enriched samples of station S2326 correspond to a mantle source with a considerable contribution of recycled sediments (EM). Sample S2326/35, which is composed of a melt almost completely depleted in EM material, corresponds to the volcanic rocks of the Marion and Prince Edward islands. The obtained and available data on the SWIR segment from Bouvet Island to Andrew Bain Fault are indicative of small mantle heterogeneities in this region. Two possible variants of their origin are considered: either preservation of the enriched material fragments in the depleted mantle during the split of Gondwana or "contamination" of the mantle with plume material with the formation of vein irregularities before opening of the ocean in this region. In the latter case, the plume material could cover a huge area not constrained by the young plume magmatism regions on Bouvet, Marion, and Prince Edward islands.

  11. Uranium isotope composition of a laterite profile during extreme weathering of basalt in Guangdong, South China

    Science.gov (United States)

    Huang, J.; Zhou, Z.; Gong, Y.; Lundstrom, C.; Huang, F.

    2015-12-01

    Rock weathering and soil formation in the critical zone are important for material cycle from the solid Earth to superficial system. Laterite is a major type of soil in South China forming at hot-humid climate, which has strong effect on the global uranium cycle. Uranium is closely related to the environmental redox condition because U is stable at U(Ⅳ) in anoxic condition and U(Ⅵ) as soluble uranyl ion (UO22+) under oxic circumstance. In order to understand the behavior of U isotopes during crust weathering, here we report uranium isotopic compositions of soil and base rock samples from a laterite profile originated from extreme weathering of basalt in Guangdong, South China. The uranium isotopic data were measured on a Nu Plasma MC-ICP-MS at the University of Illinois at Urbana-Champaign using the double spike method. The δ238U of BCR-1 is -0.29±0.03‰ (relative to the international standard CRM-112A), corresponding to a 238U/235U ratio of 137.911±0.004. Our result of BCR-1 agrees with previous analyses (e.g., -0.28‰ in Weyer et al. 2008) [1]. U contents of the laterite profile decrease from 1.9 ppm to 0.9 ppm with depth, and peak at 160 - 170 cm (2.3 ppm), much higher than the U content of base rocks (~0.5 ppm). In contrary, U/Th of laterites is lower than that of base rock (0.27) except the peak at the depth of 160-170 cm (0.38), indicating significant U loss during weathering. Notably, U isotope compositions of soils show a small variation from -0.38 to -0.28‰, consistent with the base rock within analytical error (0.05‰ to 0.08‰, 2sd). Such small variation can be explained by a "rind effect" (Wang et al., 2015) [2], by which U(Ⅳ) can be completely oxidized to U(VI) layer by layer during basalt weathering by dissolved oxygen. Therefore, our study indicates that U loss during basalt weathering at the hot-humid climate does not change U isotope composition of superficial water system. [1] Weyer S. et al. (2008) Natural fractionation of 238U/235

  12. Compositional mapping of Saturn's satellite Dione with Cassini VIMS and implications of dark material in the Saturn system

    Science.gov (United States)

    Clark, R.N.; Curchin, J.M.; Jaumann, R.; Cruikshank, D.P.; Brown, R.H.; Hoefen, T.M.; Stephan, K.; Moore, Johnnie N.; Buratti, B.J.; Baines, K.H.; Nicholson, P.D.; Nelson, R.M.

    2008-01-01

    Cassini VIMS has obtained spatially resolved imaging spectroscopy data on numerous satellites of Saturn. A very close fly-by of Dione provided key information for solving the riddle of the origin of the dark material in the Saturn system. The Dione VIMS data show a pattern of bombardment of fine, sub-0.5-??m diameter particles impacting the satellite from the trailing side direction. Multiple lines of evidence point to an external origin for the dark material on Dione, including the global spatial pattern of dark material, local patterns including crater and cliff walls shielding implantation on slopes facing away from the trailing side, exposing clean ice, and slopes facing the trailing direction which show higher abundances of dark material. Multiple spectral features of the dark material match those seen on Phoebe, Iapetus, Hyperion, Epimetheus and the F-ring, implying the material has a common composition throughout the Saturn system. However, the exact composition of the dark material remains a mystery, except that bound water and, tentatively, ammonia are detected, and there is evidence both for and against cyanide compounds. Exact identification of composition requires additional laboratory work. A blue scattering peak with a strong UV-visible absorption is observed in spectra of all satellites which contain dark material, and the cause is Rayleigh scattering, again pointing to a common origin. The Rayleigh scattering effect is confirmed with laboratory experiments using ice and 0.2-??m diameter carbon grains when the carbon abundance is less than about 2% by weight. Rayleigh scattering in solids is also confirmed in naturally occurring terrestrial rocks, and in previously published reflectance studies. The spatial pattern, Rayleigh scattering effect, and spectral properties argue that the dark material is only a thin coating on Dione's surface, and by extension is only a thin coating on Phoebe, Hyperion, and Iapetus, although the dark material abundance

  13. Characterization and recognition of intraflow structures, Grande Ronde Basalt

    International Nuclear Information System (INIS)

    Long, P.E.

    1978-09-01

    This investigation was carried out as part of a feasibility study for long-term storage of nuclear waste at depth in the Pasco Basin. Three general types of intraflow structures were found at Sentinel Gap: flows with stubby, irregular columns that lack a well-developed entablature; flows consisting of multiple tiers of largely entablature-type columns; and flows with a well-developed colonnade and entablature showing a sharp break between the two. Certain features occur locally in all three types of intraflow structures: variations in fracture morphology, primary platey fracture zones, pillow-palagonite zones, and tectonically induced zones of closely spaced fractures. Fractures in each of the three types of flows were logged both at the surface and in core from Core Hole DH-5, and petrographic textures of basalt sampled from surface exposures were examined. The textures of the basalt correlate with the intraflow structures and provide a technique for identifying flows as to their general type of intraflow structure, locating internal contacts between intraflow structures and possibly estimating fracture density within flows. Fracture logging, on the other hand, does not accurately delimit intraflow structures

  14. Fungal colonies in open fractures of subseafloor basalt

    Science.gov (United States)

    Ivarsson, Magnus; Bengtson, Stefan; Skogby, Henrik; Belivanova, Veneta; Marone, Federica

    2013-08-01

    The deep subseafloor crust is one of the few great frontiers of unknown biology on Earth and, still today, the notion of the deep biosphere is commonly based on the fossil record. Interpretation of palaeobiological information is thus central in the exploration of this hidden biosphere and, for each new discovery, criteria used to establish biogenicity are challenged and need careful consideration. In this paper networks of fossilized filamentous structures are for the first time described in open fractures of subseafloor basalts collected at the Emperor Seamounts, Pacific Ocean. These structures have been investigated with optical microscopy, environmental scanning electron microscope, energy dispersive spectrometer, X-ray powder diffraction as well as synchrotron-radiation X-ray tomographic microscopy, and interpreted as fossilized fungal mycelia. Morphological features such as hyphae, yeast-like growth and sclerotia were observed. The fossilized fungi are mineralized by montmorillonite, a process that probably began while the fungi were alive. It seems plausible that the fungi produced mucilaginous polysaccharides and/or extracellular polymeric substances that attracted minerals or clay particles, resulting in complete fossilization by montmorillonite. The findings are in agreement with previous observations of fossilized fungi in subseafloor basalts and establish fungi as regular inhabitants of such settings. They further show that fossilized microorganisms are not restricted to pore spaces filled by secondary mineralizations but can be found in open pore spaces as well. This challenges standard protocols for establishing biogenicity and calls for extra care in data interpretation.

  15. Temporal redox variation in basaltic tephra from Surtsey volcano (Iceland)

    Science.gov (United States)

    Schipper, C. Ian; Moussallam, Yves

    2017-10-01

    The oxidation state of magma controls and/or tracks myriad petrologic phenomena, and new insights into oxidation are now made possible by high-resolution measurements of Fe3+/∑Fe in volcanic glasses. We present new μ-XANES measurements of Fe3+/∑Fe in a time series of basaltic tephra from the 1963-1967 eruption of Surtsey (Iceland), to examine if the magma mixing between alkalic and tholeiitic basalts that is apparent in the major and trace elements of these glasses is also represented in their oxidation states. Raw Fe3+/∑Fe data show a temporal trend from oxidized to reduced glasses, and this is accompanied by decreasing indices of mantle enrichment (e.g., La/Yb, Zr/Y). When expressed as composition- and temperature-corrected fO2, the trend has a similar magnitude ( 0.3 log units) to the variation in fO2 due to ridge-plume interaction along the Reykjanes Ridge. These data indicate that the oxidation state of mixed magmas can be retained through fractionation and degassing processes, and that matrix glass Fe3+/∑Fe in tephras can be used to make inferences about the relative oxidation states of parental magmas during nuanced magma mixing.

  16. The Disruption of Tephra Fall Deposits by Basaltic Lava Flows

    Science.gov (United States)

    Brown, R. J.; Thordarson, T.; Self, S.; Blake, S.

    2010-12-01

    Complex physical and stratigraphic relationships between lava and proximal tephra fall deposits around vents of the Roza Member in the Columbia River Basalt Province, (CRBP), USA, illustrate how basaltic lavas can disrupt, dissect (spatially and temporally) and alter tephra fall deposits. Thin pahoehoe lobes and sheet lobes occur intercalated with tephra deposits and provide evidence for synchronous effusive and explosive activity. Tephra that accumulated on the tops of inflating pahoehoe flows became disrupted by tumuli, which dissected the overlying sheet into a series of mounds. During inflation of subjacent tumuli tephra percolated down into the clefts and rubble at the top of the lava, and in some cases came into contact with lava hot enough to thermally alter it. Lava breakouts from the tumuli intruded up through the overlying tephra deposit and fed pahoehoe flows that spread across the surface of the aggrading tephra fall deposit. Non-welded scoria fall deposits were compacted and welded to a depth of ~50 cm underneath thick sheet lobes. These processes, deduced from the field relationships, have resulted in considerable stratigraphic complexity in proximal regions. We also demonstrate that, when the advance of lava and the fallout of tephra are synchronous, the contacts of some tephra sheets can be diachronous across their extent. The net effect is to reduce the usefulness of pyroclastic deposits in reconstructing eruption dynamics.

  17. Development of near-zero water consumption cement materials via the geopolymerization of tektites and its implication for lunar construction

    Science.gov (United States)

    Wang, Kai-Tuo; Tang, Qing; Cui, Xue-Min; He, Yan; Liu, Le-Ping

    2016-07-01

    The environment on the lunar surface poses some difficult challenges to building long-term lunar bases; therefore, scientists and engineers have proposed the creation of habitats using lunar building materials. These materials must meet the following conditions: be resistant to severe lunar temperature cycles, be stable in a vacuum environment, have minimal water requirements, and be sourced from local Moon materials. Therefore, the preparation of lunar building materials that use lunar resources is preferred. Here, we present a potential lunar cement material that was fabricated using tektite powder and a sodium hydroxide activator and is based on geopolymer technology. Geopolymer materials have the following properties: approximately zero water consumption, resistance to high- and low-temperature cycling, vacuum stability and good mechanical properties. Although the tektite powder is not equivalent to lunar soil, we speculate that the alkali activated activity of lunar soil will be higher than that of tektite because of its low Si/Al composition ratio. This assumption is based on the tektite geopolymerization research and associated references. In summary, this study provides a feasible approach for developing lunar cement materials using a possible water recycling system based on geopolymer technology.

  18. Development of near-zero water consumption cement materials via the geopolymerization of tektites and its implication for lunar construction.

    Science.gov (United States)

    Wang, Kai-Tuo; Tang, Qing; Cui, Xue-Min; He, Yan; Liu, Le-Ping

    2016-07-13

    The environment on the lunar surface poses some difficult challenges to building long-term lunar bases; therefore, scientists and engineers have proposed the creation of habitats using lunar building materials. These materials must meet the following conditions: be resistant to severe lunar temperature cycles, be stable in a vacuum environment, have minimal water requirements, and be sourced from local Moon materials. Therefore, the preparation of lunar building materials that use lunar resources is preferred. Here, we present a potential lunar cement material that was fabricated using tektite powder and a sodium hydroxide activator and is based on geopolymer technology. Geopolymer materials have the following properties: approximately zero water consumption, resistance to high- and low-temperature cycling, vacuum stability and good mechanical properties. Although the tektite powder is not equivalent to lunar soil, we speculate that the alkali activated activity of lunar soil will be higher than that of tektite because of its low Si/Al composition ratio. This assumption is based on the tektite geopolymerization research and associated references. In summary, this study provides a feasible approach for developing lunar cement materials using a possible water recycling system based on geopolymer technology.

  19. Summary of a Gas Transport Tracer Test in the Deep Cerros Del Rio Basalts, Mesita del Buey, Los Alamos NM.

    Energy Technology Data Exchange (ETDEWEB)

    Stauffer, Philip H. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Rahn, Thomas A. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Ortiz, John Philip [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Salazar, Larry Joseph [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Boukhalfa, Hakim [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Snyder, Emily Elisabeth [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2018-01-16

    Here we describe results from a tracer test in the Cerros del Rio basalt beneath Mesita del Buey, Technical Area 54 (TA-54) at Los Alamos National Laboratory (LANL or the Laboratory). This report follows from plans outlined in our previous Tracer Test Work Plan (LANL 2016). These activities were conducted by LANL to further characterize subsurface properties of the Cerros del Rio basalts at Material Disposal Area (MDA) L (Figure 1.1-1). The work presented follows from the “Interim Measures Work Plan for Soil-Vapor Extraction of Volatile Organic Compounds from Material Disposal Area L, Technical Area 54, Revision 1,” submitted to the New Mexico Environment Department (NMED) in September 2014 (LANL 2014). Remediation of the MDA L vapor plume by soil-vapor extraction (SVE) is recommended as part of the final remedy in the “Corrective Measures Evaluation Report for Material Disposal Area L, Solid Waste Management Unit 54-006, at Technical Area 54, Revision 2” to meet a remedial action objective of preventing groundwater from being impacted above a regulatory standard by the transport of volatile organic compounds (VOCs) to groundwater through soil vapor (LANL 2011).

  20. Evaluation of thermobarometry for spinel lherzolite fragments in alkali basalts

    Science.gov (United States)

    Ozawa, Kazuhito; Youbi, Nasrrddine; Boumehdi, Moulay Ahmed; McKenzie, Dan; Nagahara, Hiroko

    2017-04-01

    Geothermobarometry of solid fragments in kimberlite and alkali basalts, generally called "xenoliths", provides information on thermal and chemical structure of lithospheric and asthenospheric mantle, based on which various chemical, thermal, and rheological models of lithosphere have been constructed (e.g., Griffin et al., 2003; McKenzie et al., 2005; Ave Lallemant et al., 1980). Geothermobarometry for spinel-bearing peridotite fragments, which are frequently sampled from Phanerozoic provinces in various tectonic environments (Nixon and Davies, 1987), has essential difficulties, and it is usually believed that appropriated barometers do not exist for them (O'Reilly et al., 1997; Medaris et al., 1999). Ozawa et al. (2016; EGU) proposed a method of geothermobarometry for spinel lherzolite fragments. They applied the method to mantle fragments in alkali basalts from Bou Ibalhatene maars in the Middle Atlas in Morocco (Raffone et al. 2009; El Azzouzi et al., 2010; Witting et al., 2010; El Messbahi et al., 2015). Ozawa et al. (2016) obtained 0.5GPa pressure difference (1.5-2.0GPa) for 100°C variation in temperatures (950-1050°C). However, it is imperative to verify the results on the basis of completely independent data. There are three types of independent information: (1) time scale of solid fragment extraction, which may be provided by kinetics of reactions induced by heating and/or decompression during their entrapment in the host magma and transportation to the Earth's surface (Smith, 1999), (2) depth of the host basalt formation, which may be provided by the petrological and geochemical studies of the host basalts, and (3) lithosphere-asthenosphere boundary depths, which may be estimated by geophysical observations. Among which, (3) is shown to be consistent with the result in Ozawa et al. (2016). We here present that the estimated thermal structure just before the fragment extraction is fully supported by the information of (1) and (2). Spera (1984) reviewed

  1. Corrosion of copper and copper alloys in a basaltic repository environment

    International Nuclear Information System (INIS)

    Brehm, W.F.

    1990-01-01

    Corrosion testing done on copper and copper alloys in support of the basalt repository program is discussed. Tests were performed under anoxic conditions at 50C, 100C, 150C and 200C in the presence of a saturated basalt-bentonite packing. Tests were also performed in an air/steam mixture at temperatures between 150C and 200C. Some tests, particularly those in air/steam mixtures, were done in the presence of radiation fields of 10 2 , 10 3 or 10 4 rad/h. Exposure periods were up to 28 months. A synthetic groundwater, Grande Ronde ≠4, was used. The materials studied were ASTM B402μm·a for copper and 17 μm·a for cupronickel, but the average rates were muμm·a was obtained. The rates at longer times were less than a third of this value. Corrosion increased monotonically with time and temperature. Chalcocite (Cu 2 S) was the corrosion product at 200C. There was no detectable radiation effect, and no pitting was observed. In air/steam corrosion was uniform with no pitting. Linear corrosion was observed for pure copper. The maximum corrosion penetration after 25 months was 0.13 mm at 300C; cupronickel corroded more slowly, with a maximum penetration of 0.045mm after 25 months. Cuprite (Cu 2 O) and tenorite (CuO) were identified on cupronickel, but only Cu 2 O on copper. A pronounced radiation effect was seen at 250C, but not at 150C; the surface film morphology was different under irradiation. In the short term the presence of packing increased the corrosion rate. 5 refs

  2. Characterization of fibers as rockwool for insulation obtained from canary islands basalts

    Directory of Open Access Journals (Sweden)

    Cáceres, J. M.

    1996-06-01

    Full Text Available Glass fibers in the shape of wool were obtained at laboratory scale from three samples of basaltic rocks from the Tenerife Island. The rockwool is widely used as thermal and acoustical insulation. The ability of these rocks to be fiberized was studied by means of the viscosity curves and can be quite improved by adding calcium and magnesium. The experimental fibers obtained from the rocks directly or mixed with either CaCO3 or CaMg(CO32 ye characterized in terms of chemical composition, microstructure and thermal and mechanical properties. These properties were compared with the ones determined for four commercial samples of rockcwool, founding that they are very close. This gives good prospects to these fibers from Canarian basalts as insulation material.

    Se ha obtenido fibra de vidrio en forma de lana, a escala de laboratorio, a partir de tres muestras de rocas basálticas de la Isla de Tenerife. La lana de roca se emplea extensamente como aislamiento térmico y acústico. La aptitud de estas rocas para su fibrado, estudiada mediante las curvas de viscosidad, mejora considerablemente con la adición de calcio y magnesio. Las fibras experimentales, obtenidas tanto a partir de las rocas directamente, como mezcladas en diferentes proporciones con CaCO3 o CaMg(CO32, se han caracterizado en lo referente a la composición química, la microestructura y propiedades térmicas y mecánicas. Así mismo, se han comparado estas propiedades con las determinadas para cuatro muestras comerciales de lana de roca, permitiendo comprobar que son bastante semejantes, lo que hace prever unas buenas cualidades para estas fibras de basaltos canarios en aplicaciones de aislamiento térmico y acústico.

  3. Structural control on basaltic dike and sill emplacement, Paiute Ridge mafic intrusion complex, southern Nevada

    International Nuclear Information System (INIS)

    Carter Krogh, K.E.; Valentine, G.A.

    1996-08-01

    Late Miocene basaltic sills and dikes in the Paiute Ridge area of southern nevada show evidence that their emplacement was structurally controlled. Basaltic dikes in this area formed by dilating pre-existing vertical to steeply E-dipping normal faults. Magma propagation along these faults must have required less energy than the creation of a self-propagated fracture at dike tips and the magma pressure must have been greater than the compressive stress perpendicular to the fault surface. N- to NE-trending en echelon dikes formed locally and are not obviously attached to the three main dikes in the area. The en echelon segments are probably pieces of deeper dikes, which are segmented perhaps as a result of a documented rotation of the regional stresses. Alternatively, changes in orientation of principal stresses in the vicinity of each en echelon dike could have resulted from local loads associated with paleotopographic highs or nearby structures. Sills locally branched off some dikes within 300 m of the paleosurface. These subhorizontal bodies occur consistently in the hanging wall block of the dike-injected faults, and intrude Tertiary tuffs near the Paleozoic-Tertiary contact. The authors suggest that the change in stresses near the earth's surface, the material strength of the tuff and paleozoic rocks, and the Paleozoic bedding dip direction probably controlled the location of sill formation and direction of sill propagation. The two largest sills deflected the overlying tuffs to form lopoliths, indicating that the magma pressure exceeded vertical stresses at that location and that the shallow level and large size of the sills allowed interaction with the free (earth's) surface. 32 refs., 4 figs., 1 tab

  4. Conduit margin heating and deformation during the AD 1886 basaltic Plinian eruption at Tarawera volcano, New Zealand.

    Science.gov (United States)

    Schauroth, Jenny; Wadsworth, Fabian B; Kennedy, Ben; von Aulock, Felix W; Lavallée, Yan; Damby, David E; Vasseur, Jérémie; Scheu, Bettina; Dingwell, Donald B

    During explosive eruptions, a suspension of gas and pyroclasts rises rapidly within a conduit. Here, we have analysed textures preserved in the walls of a pyroclastic feeder dyke of the AD 1886 Tarawera basaltic Plinian fissure eruption. The samples examined consist of basaltic ash and scoria plastered onto a conduit wall of a coherent rhyolite dome and a welded rhyolitic dome breccia. We examine the textural evidence for the response of the wall material, built of ∼75 vol.% glass and ∼25 vol.% crystals (pore-free equivalent), to mass movement in the adjacent conduit. In the rhyolitic wall material, we quantify the orientation and aspect ratio of biotite crystals as strain markers of simple shear deformation, and interpret juxtaposed regions of vesiculation and vesicle collapse as evidence of conduit wall heating. Systematic changes occur close to the margin: (1) porosity is highly variable, with areas locally vesiculated or densified, (2) biotite crystals are oriented with their long axis parallel to the margin, (3) the biotites have greater aspect ratios close to the margin and (4) the biotite crystals are fractured. We interpret the biotite phenocryst deformation to result from crystal fracture, rotation and cleavage-parallel bookcase translation. These textural observations are inferred to indicate mechanical coupling between the hot gas-ash jet and the conduit wall and reheating of wall rock rhyolite. We couple these observations with a simple 1D conductive heating model to show what minimum temperature the conduit wall needs to reach in order to achieve a temperature above the glass transition throughout the texturally-defined deformed zone. We propose that conduit wall heating and resulting deformation influences conduit margin outgassing and may enhance the intensity of such large basaltic eruptions.

  5. Post-Columbia River Basalt Group stratigraphy and map compilation of the Columbia Plateau, Oregon

    International Nuclear Information System (INIS)

    Farooqui, S.M.; Bunker, R.C.; Thoms, R.E.; Clayton, D.C.; Bela, J.L.

    1981-01-01

    This report presents the results of reconnaissance mapping of sedimentary deposits and volcanic rocks overlying the Columbia River Basalt. The project area covers parts of the Dalles, Pendleton, Grangeville, Baker, Canyon City, and Bend. The mapping was done to provide stratigraphic data on the sedimentary deposits and volcanic rocks overlying the Columbia River Basalt Group. 160 refs., 16 figs., 1 tab

  6. Importance of plagioclase morphology and composition in magmagenesis of the Carlsberg Ridge basalts

    Digital Repository Service at National Institute of Oceanography (India)

    Iyer, S.D.; Banerjee, R.

    The morphology and chemical composition of more than 200 plagioclase crystals in the Carlsberg Ridge basalts (3~'35' and 3~'41'N) in relation to the magmagenesis of the basalts is examined. The results indicate that the different morphotypes...

  7. From mantle roots to surface eruptions: Cenozoic and Mesozoic continental basaltic magmatism

    Czech Academy of Sciences Publication Activity Database

    Kämpf, H.; Németh, K.; Puziewicz, J.; Mrlina, Jan; Geissler, W.H.

    2015-01-01

    Roč. 104, č. 8 (2015), s. 1909-1912 ISSN 1437-3254 Institutional support: RVO:67985530 Keywords : continental basaltic volcanism * BASALT 2013 conference * Cenozoic * Mesozoic Subject RIV: DC - Siesmology, Volcanology, Earth Structure Impact factor: 2.133, year: 2015

  8. Prokaryotic diversity, distribution, and insights into their role in biogeochemical cycling in marine basalts

    Energy Technology Data Exchange (ETDEWEB)

    Mason, Olivia U.; Di Meo-Savoie, Carol A.; Van Nostrand, Joy D.; Zhou, Jizhong; Fisk, Martin R.; Giovannoni, Stephen J.

    2008-09-30

    We used molecular techniques to analyze basalts of varying ages that were collected from the East Pacific Rise, 9 oN, from the rift axis of the Juan de Fuca Ridge, and from neighboring seamounts. Cluster analysis of 16S rDNA Terminal Restriction Fragment Polymorphism data revealed that basalt endoliths are distinct from seawater and that communities clustered, to some degree, based on the age of the host rock. This age-based clustering suggests that alteration processes may affect community structure. Cloning and sequencing of bacterial and archaeal 16S rRNA genes revealed twelve different phyla and sub-phyla associated with basalts. These include the Gemmatimonadetes, Nitrospirae, the candidate phylum SBR1093 in the c, andin the Archaea Marine Benthic Group B, none of which have been previously reported in basalts. We delineated novel ocean crust clades in the gamma-Proteobacteria, Planctomycetes, and Actinobacteria that are composed entirely of basalt associated microflora, and may represent basalt ecotypes. Finally, microarray analysis of functional genes in basalt revealed that genes coding for previously unreported processes such as carbon fixation, methane-oxidation, methanogenesis, and nitrogen fixation are present, suggesting that basalts harbor previously unrecognized metabolic diversity. These novel processes could exert a profound influence on ocean chemistry.

  9. Petrological Characteristics and Genesis of the Central Indian Ocean Basin Basalts

    Digital Repository Service at National Institute of Oceanography (India)

    Das, P.; Iyer, S.D.; Hazra, S.

    ferrobasaltic composition. The basalts have high incompatible elements (Zr 63-228 ppm; Nb approx. 1-5 ppm; Ba approx. 15-78 ppm; La approx. 3-16 ppm), a similar U/Pb (0.02-0.4) ratio as the normal mid-oceanic basalt (0.16 plus or minus 0.07) but the Ba/Nb (12...

  10. Petrological constraints on the high-Mg basalts from Capo Marargiu (Sardinia, Italy): Evidence of cryptic amphibole fractionation in polybaric environments

    Science.gov (United States)

    Tecchiato, Vanni; Gaeta, Mario; Mollo, Silvio; Scarlato, Piergiorgio; Bachmann, Olivier; Perinelli, Cristina

    2018-01-01

    This study deals with the textural and compositional characteristics of the calc-alkaline stratigraphic sequence from Capo Marargiu Volcanic District (CMVD; Sardinia island, Italy). The area is dominated by basaltic to intermediate hypabyssal (dikes and sills) and volcanic rocks (lava flows and pyroclastic deposits) emplaced during the Oligo-Miocene orogenic magmatism of Sardinia. Interestingly, a basaltic andesitic dome hosts dark-grey, crystal-rich enclaves containing up 50% of millimetre- to centimetre-sized clinopyroxene and amphibole crystals. This mineral assemblage is in equilibrium with a high-Mg basalt recognised as the parental magma of the entire stratigraphic succession at CMVD. Analogously, centimetre-sized clots of medium- and coarse-grained amphibole + plagioclase crystals are entrapped in andesitic dikes that ultimately intrude the stratigraphic sequence. Amphibole-plagioclase cosaturation occurs at equilibrium with a differentiated basaltic andesite. Major and trace element modelling indicates that the evolutionary path of magma is controlled by a two-step process driven by early olivine + clinopyroxene and late amphibole + plagioclase fractionation. In this context, enclaves represent parts of a cumulate horizon segregated at the early stage of differentiation of the precursory high-Mg basalt. This is denoted by i) resorption effects and sharp transitions between Mg-rich and Mg-poor clinopyroxenes, indicative of pervasive dissolution phenomena followed by crystal re-equilibration and overgrowth, and ii) reaction minerals found in amphibole coronas formed at the interface with more differentiated melts infiltrating within the cumulate horizon, and carrying the crystal-rich material with them upon eruption. Coherently, the mineral chemistry and phase relations of enclaves indicate crystallisation in a high-temperature, high-pressure environment under water-rich conditions. On the other hand, the upward migration and subsequent fractionation of the

  11. Indigenous lunar construction materials

    Science.gov (United States)

    Rogers, Wayne P.; Sture, Stein

    1991-01-01

    The utilization of local resources for the construction and operation of a lunar base can significantly reduce the cost of transporting materials and supplies from Earth. The feasibility of processing lunar regolith to form construction materials and structural components is investigated. A preliminary review of potential processing methods such as sintering, hot-pressing, liquification, and cast basalt techniques, was completed. The processing method proposed is a variation on the cast basalt technique. It involves liquification of the regolith at 1200-1300 C, casting the liquid into a form, and controlled cooling. While the process temperature is higher than that for sintering or hot-pressing (1000-1100 C), this method is expected to yield a true engineering material with low variability in properties, high strength, and the potential to form large structural components. A scenario for this processing method was integrated with a design for a representative lunar base structure and potential construction techniques. The lunar shelter design is for a modular, segmented, pressurized, hemispherical dome which could serve as habitation and laboratory space. Based on this design, estimates of requirements for power, processing equipment, and construction equipment were made. This proposed combination of material processing method, structural design, and support requirements will help to establish the feasibility of lunar base construction using indigenous materials. Future work will refine the steps of the processing method. Specific areas where more information is needed are: furnace characteristics in vacuum; heat transfer during liquification; viscosity, pouring and forming behavior of molten regolith; design of high temperature forms; heat transfer during cooling; recrystallization of basalt; and refinement of estimates of elastic moduli, compressive and tensile strength, thermal expansion coefficient, thermal conductivity, and heat capacity. The preliminary

  12. Experimental investigation of the reaction between corundum xenocrysts and alkaline basaltic host magma: Constraints on magma residence times of basalt-hosted sapphires

    Science.gov (United States)

    Baldwin, L. C.; Ballhaus, C.

    2018-03-01

    Megacrystic sapphires (Fe-Ti-rich corundum) of up to 5 cm in size are well known from alkaline mafic rocks from intra-continental rift-related magmatic fields. There is no doubt that these sapphires represent xenocrysts that were trapped from their original lithology by ascending basaltic magmas carrying them to the Earth's surface. Most studies about basalt-hosted sapphires address the question about the origin of the sapphires, but there is hardly any information available about the time the sapphires resided inside the carrier melt. Sapphires are in reaction relationship with basalt and produce spinel coronas at the sapphire-basalt interface, spatially separating the mutually incompatible phases from one another. Assuming isothermal and isobaric conditions of spinel rim formation, the rim-thickness should be a function of the reaction time with the basaltic melt. In this paper, we report time-series experiments aimed at investigating the kinetics of spinel rim formation due to igneous corrosion of corundum. Therefore, we reacted corundum fragments with alkaline basalt powder at 1250 °C and 1GPa, using a Piston Cylinder Apparatus. The width of the spinel rim was used to estimate a residence time. Extrapolating the experimentally derived reaction rates to the thickness of natural spinel rims as described from the Siebengebirge Volcanic Field, Germany, and from Changle, China, we estimated residence times in the order of a few weeks to months.

  13. Optimization of Life Cycle Extension of Asphalt Concrete Mixtures in regard to Material Properties, Structural Design, and Economic Implications

    Directory of Open Access Journals (Sweden)

    Jan Mikolaj

    2016-01-01

    Full Text Available Design of ACM life cycle is defined with respect to traffic load acting on the pavement and road class for a period of about 20 years. In practice, reconstruction is usually pending until the end of the life cycle after which the reconstruction takes place and the original materials are replaced by new materials. Life cycle of the pavement construction in road structure is significantly longer than that of the ACM; it is therefore necessary to consider ACM from a long term viewpoint, that is, exceeding their life expectancy. This paper describes a methodology which consists of analytical calculations, experimental measurements, and optimization of the ACM life cycle with the use of a rehabilitation action to provide new physical properties of pavement surfacing in different periods of the original life cycle. The aim is to attain maximal economic effectiveness, by minimizing financial costs for rehabilitation and maintenance and economic costs of road user. Presented method allows deriving optimal life cycle from various rehabilitation alternatives for particular ACM with the fact that all the necessary parameters are derived from specific experimental measurements and calculations. The method is applicable to all types of ACM materials; however, for each material, it is necessary to carry out the necessary measurements and tests. The article describes the methodology and case study results for a particular type of ACM material.

  14. Reference waste form, basalts, and ground water systems for waste interaction studies

    Energy Technology Data Exchange (ETDEWEB)

    Deju, R.A.; Ledgerwood, R.K.; Long, P.E.

    1978-09-01

    This report summarizes the type of waste form, basalt, and ground water compositions to be used in theoretical and experimental models of the geochemical environment to be simulated in studying a typical basalt repository. Waste forms to be used in the experiments include, and are limited to, glass, supercalcine, and spent unreprocessed fuel. Reference basalts selected for study include the Pomona member and the Umtanum Unit, Shwana Member, of the Columbia River Basalt Group. In addition, a sample of the Basalt International Geochemical Standard (BCR-1) will be used for cross-comparison purposes. The representative water to be used is of a sodium bicarbonate composition as determined from results of analyses of deep ground waters underlying the Hanford Site. 12 figures, 13 tables.

  15. Corrosion of uncoated and oxide-coated basalt fibre in different alkaline media

    International Nuclear Information System (INIS)

    Rybin, V.A.; Utkin, A.V.; Baklanova, N.I.

    2016-01-01

    Highlights: • Alkaline corrosion of uncoated and coated basalt fibre in alkali media was studied. • Degradation of the fibre involves the dissolution of alumosilicate network in alkali media. • Insoluble shell from iron and calcium hydroxides and carbonates is formed. • Zirconia and titania coatings slow down the corrosion of basalt fibre significantly. - Abstract: The corrosion behaviour of the zirconium dioxide and titanium dioxide coated basalt fibre in sodium and calcium hydroxide solutions was studied. The morphology, elemental, phase composition of fibre before and after exposure to alkaline media was examined by different analytical techniques. It was shown that the oxide coatings slow down corrosion, and zirconium dioxide slows down corrosion of basalt fibre to a higher extent than titanium dioxide. The morphology and composition of solid corrosion products depend on a type of alkaline medium. The schemes of corrosion for the uncoated and coated basalt fibres in alkaline media were proposed.

  16. Reference waste form, basalts, and ground water systems for waste interaction studies

    International Nuclear Information System (INIS)

    Deju, R.A.; Ledgerwood, R.K.; Long, P.E.

    1978-09-01

    This report summarizes the type of waste form, basalt, and ground water compositions to be used in theoretical and experimental models of the geochemical environment to be simulated in studying a typical basalt repository. Waste forms to be used in the experiments include, and are limited to, glass, supercalcine, and spent unreprocessed fuel. Reference basalts selected for study include the Pomona member and the Umtanum Unit, Shwana Member, of the Columbia River Basalt Group. In addition, a sample of the Basalt International Geochemical Standard (BCR-1) will be used for cross-comparison purposes. The representative water to be used is of a sodium bicarbonate composition as determined from results of analyses of deep ground waters underlying the Hanford Site. 12 figures, 13 tables

  17. Late Pleistocene and Early Holocene Rock Art from the Mongolian Altai: The Material and its Cultural Implications

    Directory of Open Access Journals (Sweden)

    Esther Jacobson-Tepfer

    2013-09-01

    Full Text Available Rock-pecked images from the northern Mongolian Altai attest to the presence of human communities within the high valleys of that region during the Late Pleistocene and Early Holocene. The material provides evidence that is hitherto largely missing from the archaeological record of that region. This paper reviews the rock art, its find sites and larger physical contexts and uses evidence from paleoenvironmental studies to propose dating and cultural significance. The material is compared with other sites said to have Paleolithic imagery from Mongolia and the adjoining Russian Altai. The body of presented material offers a major resource for the study of early hunter-gatherer communities at the interface of Central and North Asia.

  18. Suspension of bed material over sand bars in the Lower Mississippi River and its implications for Mississippi delta environmental restoration

    Science.gov (United States)

    Ramirez, Michael T.; Allison, Mead A.

    2013-06-01

    specific pathways for sand transport in the lower reaches of large rivers, including the Mississippi, is a key for addressing multiple significant geologic problems, such as delta building and discharge to the oceans, and for environmental restoration efforts in deltaic environments threatened by rising sea levels. Field studies were performed in the Mississippi River 75-100 km upstream of the Gulf of Mexico outlet in 2010-2011 to examine sand transport phenomena in the tidally affected river channel over a range of discharges. Methods included mapping bottom morphology (multibeam sonar), cross-sectional and longitudinal measurements of water column velocity and acoustic backscatter, suspended sediment sampling, and channel-bed sampling. Substantial interaction was observed between the flow conditions in the river (boundary shear stress), channel-bed morphology (size and extent of sandy bedforms), and bed material sand transport (quantity, transport mode, and spatial distribution). A lateral shift was observed in the region of maximum bed material transport from deep to shallow areas of subaqueous sand bars with increasing water discharge. Bed material was transported both in traction and in suspension at these water discharges, and we posit that the downriver flux of sand grains is composed of both locally- and drainage basin-sourced material, with distinct transport pathways and relations to flow conditions. We provide suggestions for the optimal design and operation of planned river diversion projects.

  19. Crystallization of tholeiitic basalt in Alae Lava Lake, Hawaii

    Science.gov (United States)

    Peck, D.L.; Wright, T.L.; Moore, J.G.

    1966-01-01

    The eruption of Kilauea Volcano August 21-23, 1963, left 600,000 cubic meters of basaltic lava in a lava lake as much as 15 meters deep in Alae pit crater. Field studies of the lake began August 27 and include repeated core drilling, measurements of temperature in the crust and melt, and precise level surveys of the lake surface. The last interstitial melt in the lake solidified late in September 1964; by mid August 1965 the maximum temperature was 690??C at a depth of 11.5 meters. Pumice air-quenched from about 1140??C contains only 5 percent crystals - clinopyroxene, cuhedral olivine (Fo 80), and a trace of plagioclase, (An 70). Drill cores taken from the zone of crystallization in the lake show that olivine continued crystallizing to about 1070??C; below that it reacts with the melt, becoming corroded and mantled by pyroxene and plagioclase. Below 1070??C, pyroxene and plagioclase crystallized at a constant ratio. Ilmenite first appeared at about 1070??C and was joined by magnetite at about 1050??C; both increased rapidly in abundance to 1000??C. Apatite first appeared as minute needles in interstitial glass at 1000??C. Both the abundance and index of refraction of glass quenched from melt decreased nearly linearly with falling temperature. At 1070??C the quenched lava contains about 65 percent dark-brown glass with an index of 1.61; at 980??C it contains about 8 percent colorless glass with an index of 1.49. Below 980??C, the percentage of glass remained constant. Progressive crystallization forced exsolution of gases from the melt fraction; these formed vesicles and angular pores, causing expansion of the crystallizing lava and lifting the surface of the central part of the lake an average of 19.5 cm. The solidified basalt underwent pneumatolitic alteration, including deposition of cristobalite at 800??C, reddish alteration of olivine at 700??C, tarnishing of ilmenite at 550??C, deposition of anhydrite at 250??C, and deposition of native sulfur at 100??C

  20. Geoscience parameter data base handbook: granites and basalts

    Energy Technology Data Exchange (ETDEWEB)

    1979-12-01

    The Department of Energy has the responsibility for selecting and constructing Federal repositories for radioactive waste. The Nuclear Regulatory Commission must license such repositories prior to construction. The basic requirement in the geologic disposal of radioactive waste is stated as: placement in a geologic host whereby the radioactive waste is not in mechanical, thermal or chemical equilibrium with the object of preventing physical or chemical migration of radionuclides into the biosphere or hydrosphere in hazardous concentration (USGS, 1977). The object of this report is to document the known geologic parameters of large granite and basalt occurrences in the coterminous United States, for future evaluation in the selection and licensing of radioactive waste repositories. The description of the characteristics of certain potential igneous hosts has been limited to existing data pertaining to the general geologic character, geomechanics, and hydrology of identified occurrences. A description of the geochemistry is the subject of a separate report.

  1. Applications of dynamic crystallization studies - Lunar olivine-normative basalts

    Science.gov (United States)

    Bianco, A. S.; Taylor, L. A.

    1977-01-01

    Dynamic crystallization studies were performed on two synthetic glasses similar in composition to the mare olivine-normative basalt samples 12009 and 15555. The effects of viscosity (primarily a function of FeO) and the initial temperature of cooling on mineral chemistry, texture, and temperature of appearance of phases were investigated. Olivine compositions seem to indicate that, for the two types of melt cooled at the same rate, there are no significant differences in the degree of undercooling at which olivine nucleates, but it is found that olivine-nucleated densities differ. The cooling rate of 15555 is estimated. Since the temperature at which cooling is initiated affects texture, mineral chemistry, and temperature of appearance of phases so greatly, caution is recommended in the application of experimental data to natural rock systems.

  2. Fire performance of basalt FRP mesh reinforced HPC thin plates

    DEFF Research Database (Denmark)

    Hulin, Thomas; Hodicky, Kamil; Schmidt, Jacob Wittrup

    2013-01-01

    An experimental program was carried out to investigate the influence of basalt FRP (BFRP) reinforcing mesh on the fire behaviour of thin high performance concrete (HPC) plates applied to sandwich elements. Samples with BFRP mesh were compared to samples with no mesh, samples with steel mesh...... and samples displaying a full sandwich structure. Final results confirmed the bond loss between concrete and BFRP mesh with temperature. The available void where the epoxy burnt away allowed the concrete matrix to release pressure and limit pore stresses, delaying spalling. It also reduced the mechanical...... on a linear increase of the volume of melted epoxy and the outflow of moisture from the concrete matrix. It was concluded that the use of a BFRP mesh to reinforce HPC exposed to fire reduces the mechanical strength despite a beneficial effect related to spalling....

  3. Geomechanical testing development for the Basalt Waste Isolation Project

    International Nuclear Information System (INIS)

    Cramer, M.L.; Dischler, S.A.; Erb, D.B.; Berlin, G.T.; Wittreich, C.D.; Bauer, R.E.

    1987-04-01

    One component of this project is the development of a geomechanical testing program to support repository design, site characterization, and performance assessment requirements. Geomechanics information includes characteristics of the in situ stress field and the mechanical properties of the rock mass. The nature of the basalts at the proposed repository depth of approximately 970 m imposes some relatively unusual requirements on testing methods typically used to assess the stress state and rock mass deformability. The rock mass is closely jointed, with the spacing estimated from vertical boreholes to be in the range of 5 to 10 cm for both vertical and horizontal joint sets. The ambient temperature at depth is about 50 0 C. The rock mass is considered fully saturated. This presentation summarizes the development effort currently under way to support site characterization testing to be conducted at the candidate repository horizon in the Exploratory Shaft Facility. Development activities include hydraulic fracturing, overcoring, flat jack testing, and borehole dilatometer testing

  4. Tungsten-182 heterogeneity in modern ocean island basalts

    Science.gov (United States)

    Mundl, Andrea; Touboul, Mathieu; Jackson, Matthew G.; Day, James M. D.; Kurz, Mark D.; Lekic, Vedran; Helz, Rosalind T.; Walker, Richard J.

    2017-04-01

    New tungsten isotope data for modern ocean island basalts (OIB) from Hawaii, Samoa, and Iceland reveal variable 182W/184W, ranging from that of the ambient upper mantle to ratios as much as 18 parts per million lower. The tungsten isotopic data negatively correlate with 3He/4He. These data indicate that each OIB system accesses domains within Earth that formed within the first 60 million years of solar system history. Combined isotopic and chemical characteristics projected for these ancient domains indicate that they contain metal and are repositories of noble gases. We suggest that the most likely source candidates are mega-ultralow-velocity zones, which lie beneath Hawaii, Samoa, and Iceland but not beneath hot spots whose OIB yield normal 182W and homogeneously low 3He/4He.

  5. Geoscience parameter data base handbook: granites and basalts

    International Nuclear Information System (INIS)

    1979-12-01

    The Department of Energy has the responsibility for selecting and constructing Federal repositories for radioactive waste. The Nuclear Regulatory Commission must license such repositories prior to construction. The basic requirement in the geologic disposal of radioactive waste is stated as: placement in a geologic host whereby the radioactive waste is not in mechanical, thermal or chemical equilibrium with the object of preventing physical or chemical migration of radionuclides into the biosphere or hydrosphere in hazardous concentration (USGS, 1977). The object of this report is to document the known geologic parameters of large granite and basalt occurrences in the coterminous United States, for future evaluation in the selection and licensing of radioactive waste repositories. The description of the characteristics of certain potential igneous hosts has been limited to existing data pertaining to the general geologic character, geomechanics, and hydrology of identified occurrences. A description of the geochemistry is the subject of a separate report

  6. Interim reclamation report: Basalt Waste Isolation Project exploration shaft site

    International Nuclear Information System (INIS)

    Brandt, C.A.; Rickard, W.H. Jr.; Hefty, M.G.

    1990-02-01

    In 1968, a program was started to assess the feasibility of storing Hanford Site defense waste in deep caverns constructed in basalt. This program was expanded in 1976 to include investigations of the Hanford Site as a potential location for a mined commercial nuclear waste repository. Extensive studies of the geotechnical aspects of the site were undertaken, including preparations for drilling a large diameter Exploratory Shaft. This report describes the development of the reclamation program for the Exploratory Shaft Facility, its implementation, and preliminary estimates of its success. The goal of the reclamation program is to return sites disturbed by the repository program as nearly as practicable to their original conditions using native plant species. 43 refs., 19 figs., 9 tabs

  7. Interim reclamation report: Basalt Waste Isolation Project exploration shaft site

    Energy Technology Data Exchange (ETDEWEB)

    Brandt, C.A.; Rickard, W.H. Jr.; Hefty, M.G.

    1990-02-01

    In 1968, a program was started to assess the feasibility of storing Hanford Site defense waste in deep caverns constructed in basalt. This program was expanded in 1976 to include investigations of the Hanford Site as a potential location for a mined commercial nuclear waste repository. Extensive studies of the geotechnical aspects of the site were undertaken, including preparations for drilling a large diameter Exploratory Shaft. This report describes the development of the reclamation program for the Exploratory Shaft Facility, its implementation, and preliminary estimates of its success. The goal of the reclamation program is to return sites disturbed by the repository program as nearly as practicable to their original conditions using native plant species. 43 refs., 19 figs., 9 tabs.

  8. Characteristics Of Basaltic Sand: Size, Shape, And Composition As A Function Of Transport Process And Distance

    Science.gov (United States)

    Craddock, R. A.; Needell, Z. A.; Rose, T. R.

    2012-04-01

    Overview: The chemical and physical characteristics of sedimentary material can provide valuable clues about transport processes, distance traveled, and provenance, all of which are aspects of Martian geography that we would like to better understand. For a typical sedimentary deposit on Earth, for example, it has been shown that the ratio of feldspar to quartz can be used to assess the maturity (or transport distance) of a terrestrial deposit, because feldspar is more vulnerable to weathering than quartz. Further, chemical analysis can also be used to determine potential sediment sources, and grain-size sorting can be used to distinguish aeolian sediments (typically well-sorted) from fluvial sediments (poorly sorted in high energy environments). It is also common to use the shapes of individual quartz particles to determine transport process and distance, all of which can help us better understand the history of a sample of sedimentary material and the geological processes that created and emplaced it. These traditional sedimentological concepts are now being applied to our interpretation of Martian surface materials. Sullivan et al. [2008], for example, used grain-size and shape to assess eolian processes and to qualify transport distances of deposits found at the Spirit landing site in Gusev Crater. Stockstill-Cahill et al. [62008 used variations in mineral abundances observed in multispectral data to determine the provenance of dark dunes found in Amazonis Planitia craters. While applying our understanding of terrestrial sedimentary materials to Martian surface materials is intuitively sound and logical, the problem is that most of our current understanding is based on sediments derived from felsic materials (e.g., granite) primarily because that is the composition of most of the landmass on the Earth. However, the Martian surface is composed primarily of mafic material, or basalt, which generates much different sedimentary particles as it weathers. Instead of

  9. Repository site definition in basalt: Pasco Basin, Washington

    Energy Technology Data Exchange (ETDEWEB)

    Guzowski, R.V.; Nimick, F.B.; Muller, A.B.

    1982-03-01

    Discussion of the regional setting, geology, hydrology, and geochemistry of the Pasco Basin are included in this report. Pasco basin is a structural and topographic basin of approximately 2000 mi/sup 2/ (5180 km/sup 2/) located within the Yakima Fold Belt Subprovince of the Columbia Plateau. The stratigraphic sequence within the basin consists of an undetermined thickness of lower Miocene and younger flood basalts with interbedded and overlying sedimentary units. This sequence rests upon a basement of probably diverse rock types that may range in age from precambrian through early Tertiary. Although a large amount of information is available on the hydrology of the unconfined aquifer system, ground-water flow within the basin is, in general, poorly understood. Recharge areas for the Mabton interbed and the Saddle Mountains Formation are the highlands surrounding the basin with the flow for these units toward Gable Butte - Gable Mountain and Lake Wallula. Gable Butte - Gable Mountain probably is a ground-water sink, although the vertical flow direction in this zone is uncertain. The amount of upward vertical leakage from the Saddle Mountains Formation into the overlying sediments or to the Columbia River is unknown. Units underlying the Mabton interbed may have a flow scheme similar to those higher units or a flow scheme dominated by interbasin flow. Upward vertical leakage either throughout the basin, dominantly to the Columbia River, or dominantly to Lake Wallula has been proposed for the discharge of the lower units. None of these proposals is verified. The lateral and vertical distribution of major and minor ions in solution, Eh and pH, and ion exchange between basalt and ground-water are not well defined for the basin. Changes in the redox potential from the level of the subsurface facility to the higher stratigraphic levels along with the numerous other factors influencing K/sub d/, result in a poor understanding of the retardation process.

  10. Repository site definition in basalt: Pasco Basin, Washington

    International Nuclear Information System (INIS)

    Guzowski, R.V.; Nimick, F.B.; Muller, A.B.

    1982-03-01

    Discussion of the regional setting, geology, hydrology, and geochemistry of the Pasco Basin are included in this report. Pasco basin is a structural and topographic basin of approximately 2000 mi 2 (5180 km 2 ) located within the Yakima Fold Belt Subprovince of the Columbia Plateau. The stratigraphic sequence within the basin consists of an undetermined thickness of lower Miocene and younger flood basalts with interbedded and overlying sedimentary units. This sequence rests upon a basement of probably diverse rock types that may range in age from precambrian through early Tertiary. Although a large amount of information is available on the hydrology of the unconfined aquifer system, ground-water flow within the basin is, in general, poorly understood. Recharge areas for the Mabton interbed and the Saddle Mountains Formation are the highlands surrounding the basin with the flow for these units toward Gable Butte - Gable Mountain and Lake Wallula. Gable Butte - Gable Mountain probably is a ground-water sink, although the vertical flow direction in this zone is uncertain. The amount of upward vertical leakage from the Saddle Mountains Formation into the overlying sediments or to the Columbia River is unknown. Units underlying the Mabton interbed may have a flow scheme similar to those higher units or a flow scheme dominated by interbasin flow. Upward vertical leakage either throughout the basin, dominantly to the Columbia River, or dominantly to Lake Wallula has been proposed for the discharge of the lower units. None of these proposals is verified. The lateral and vertical distribution of major and minor ions in solution, Eh and pH, and ion exchange between basalt and ground-water are not well defined for the basin. Changes in the redox potential from the level of the subsurface facility to the higher stratigraphic levels along with the numerous other factors influencing K/sub d/, result in a poor understanding of the retardation process

  11. Tracking Hadean processes in modern basalts with 142-Neodymium

    Science.gov (United States)

    Horan, M. F.; Carlson, R. W.; Walker, R. J.; Jackson, M.; Garçon, M.; Norman, M.

    2018-02-01

    The short-lived 146Sm→142 Nd isotope system (t1/2 = 103 Ma) provides constraints on the timing and processes of terrestrial silicate fractionation during the early Hadean. Although some Archean terranes preserve variability in 142Nd/144Nd, no anomalies have been resolved previously in young rocks. This study provides high precision 142Nd/144Nd data on a suite of ocean island basalts from Samoa and Hawaii previously shown to have variable depletions in 182W/184W that are inversely correlated with 3He/4He ratios. Improved analytical techniques and multiple replicate analyses of Nd show a variation in μ142 Nd values between -1.3 and +2.7 in the suite, relative to the JNdi standard. Given the reproducibility of the standard (±2.9 ppm, 2 SD), two Samoan samples exhibit resolved variability in their 142Nd/144Nd ratios outside of their 95% confidence intervals, suggesting minor variability in the Samoan hotspot. One sample from Samoa has a higher μ142 Nd of +2.7, outside the 95% confidence interval (±1.0 ppm) of the average of the JNdi standard. Limited, but resolved, variation in 142Nd/144Nd within the suite suggests the preservation of early Hadean silicate differentiation in the sources of at least some basalts from Samoa. Larger variations of 182W/184W and 3He/4He ratios in the same samples suggest that metal-silicate separation and mantle outgassing left a more persistent imprint on the accessible mantle compared to 142Nd/144Nd ratios which are impacted by early silicate differentiation.

  12. The Influence of Topographic Obstacles on Basaltic Lava Flow Morphologies

    Science.gov (United States)

    von Meerscheidt, H. C.; Brand, B. D.; deWet, A. P.; Bleacher, J. E.; Hamilton, C. W.; Samuels, R.

    2014-12-01

    Smooth pāhoehoe and jagged ´áā represent two end-members of a textural spectrum that reflects the emplacement characteristics of basaltic lava flows. However, many additional textures (e.g., rubbly and slabby pāhoehoe) reflect a range of different process due to lava flow dynamics or interaction with topography. Unfortunately the influence of topography on the distribution of textures in basaltic lava flows is not well-understood. The 18 ± 1.0 ka Twin Craters lava flow in the Zuni-Bandera field (New Mexico, USA) provides an excellent site to study the morphological changes of a lava flow that encountered topographic obstacles. The flow field is 0.2-3.8 km wide with a prominent central tube system that intersects and wraps around a 1000 m long ridge, oriented perpendicular to flow. Upstream of the ridge, the flow has low-relief inflation features extending out and around the ridge. This area includes mildly to heavily disrupted pāhoehoe with interdispersed agglutinated masses, irregularly shaped rubble and lava balls. Breakouts of ´áā and collapse features are also common. These observations suggest crustal disruption due to flow-thickening upstream from the ridge and the movement of lava out and around the obstacle. While the ridge influenced the path of the tube, which wraps around the southern end of the ridge, the series of collapse features and breakouts of ´áā along the tube system are more likely a result of changes in flux throughout the tube system because these features are found both upstream and downstream of the obstacle. This work demonstrates that topography can significantly influence the formation history and surface disruption of a flow field, and in some cases the influence of topography can be separated from the influences of changes in flux along a tube system.

  13. The mode of emplacement of Neogene flood basalts in eastern Iceland: Facies architecture and structure of simple aphyric basalt groups

    Science.gov (United States)

    Óskarsson, Birgir V.; Riishuus, Morten S.

    2014-12-01

    Simple flows (tabular) in the Neogene flood basalt sections of Iceland are described and their mode of emplacement assessed. The flows belong to three aphyric basalt groups: the Kumlafell group, the Hólmatindur group and the Hjálmadalur group. The groups can be traced over 50 km and originate in the Breiðdalur-Thingmuli volcanic zone. The groups have flow fields that display mixed volcanic facies architecture and can be classified after dominating type morphology. The Kumlafell and the Hólmatindur groups have predominantly simple flows of pāhoehoe and rubbly pāhoehoe morphologies with minor compound or lobate pāhoehoe flows. The Hjálmadalur group has simple flows of rubbly pāhoehoe, but also includes minor compound or lobate flows of rubble and 'a'ā. Simple flows are most common in the distal and medial areas from the vents, while more lobate flows in proximal areas. The simple flows are formed by extensive sheet lobes that are several kilometers long with plane-parallel contacts, some reaching thicknesses of ~ 40 m (aspect ratios structures. Their internal structure consists generally of a simple upper vesicular crust, a dense core and a thin basal vesicular zone. The brecciated flow-top is formed by clinker and crustal rubble, the clinker often welded or agglutinated. The simple flows erupted from seemingly short-lived fissures and have the characteristics of cooling-limited flows. We estimate the effusion rates to be ~ 105 m3/s for the simple flows of the Kumlafell and Hólmatindur groups and ~ 104 m3/s for the Hjálmadalur group. The longest flows advanced 15-20 km from the fissures, with lava streams of fast propagating flows inducing tearing and brecciation of the chilled crust. Compound or lobate areas appear to reflect areas of low effusion rates or the interaction of the lava with topographic barriers or wetlands, resulting in chaotic flowage. Slowing lobes with brecciated flow-tops developed into 'a'ā flows. The groups interdigitated with lava

  14. Implications of the use of low-pH cementitious materials in high activity radioactive waste repositories

    International Nuclear Information System (INIS)

    Garcia Calvo, J.L.; Alonso, M.C.; Fernandez Luco, L.; Hidalgo, A.; Sanchez, M.

    2008-01-01

    One of the most accepted engineering construction concepts for high radioactive nuclear waste of underground repositories considers the use of low pH cementitious materials, in order to avoid the formation of an alkaline plume fluid which perturbs one of the engineered barriers of the repository, the bentonite. The accepted solution to maintain the bentonite stability, which is function of the pH, is to develop cementitious materials that generate pore waters with pH ≤ 11, because the corrosion velocity of the clay is significantly reduced below this value. The IETcc-CSIC has focused the research activity on low-pH cementitious materials using two cements: Ordinary Portland Cements (OPC) and Calcium Aluminates Cements (CAC). In both cases, the achievement of a low-pH environment implies the use of high content of mineral admixtures to prepare the binder. Obviously, the inclusion of high contents of mineral admixtures in the cement formulation modifies most of the concrete 'standard' properties and the microstructure of the obtained cement products. When designing a concrete based on low-pH binders, not only the functional requirements have to be reached but also the modifications of the basic properties of the concrete must be taken into account. Besides, due to the location and the long service life of this type of products, their durability properties must be also guaranteed. This paper deals with the procedure followed in the design of a specific application of low pH cements; for instance, the shotcrete plug fabrication. The challenge of this type of use (shotcreting) is more complex taking into account that requires the employment of additives that must be compatible with the concrete mixture. Furthermore, their effectiveness must be assured without increase the pH above the admissible levels. Therefore, their compatibility with admixtures is tested in the present work. The compliance of the requirements for a shotcrete plug was evaluated at laboratory scale

  15. Petrological and Geochemical characterization of central Chihuahua basalts: a possible local sign of rifting activity

    Science.gov (United States)

    Espejel-Garcia, V. V.; Garcia-Rascon, M.; Villalobos-Aragon, A.; Morton-Bermea, O.

    2012-12-01

    The central part of the mexican state, Chihuahua, is the oriental border of the Sierra Madre Occidental (silicic large igneous province), which consist of series of ignimbrites divided into two volcanic groups of andesites and rhyolites. In the central region of Chihuahua, the volcanic rocks are now part of the Basin and Range, allowing the presence of mafic rocks in the lower areas. The study area is located approximately 200 km to the NW of Chihuahua city near to La Guajolota town, in the Namiquipa County. There are at least 5 outcrops of basalts to the west of the road, named Puerto de Lopez, Malpaises, El Tascate, Quebrada Honda, and Carrizalio, respectively. These outcrops have only been previously described by the Mexican Geologic Survey (SGM) as thin basaltic flows, with vesicles filled with quartz, and phenocrystals of labradorite, andesine, oligoclase and olivine. Petrologically, the basalts present different textures, from small phenocrysts of plagioclase in a very fine matrix to large, zoned and sometimes broken phenocrysts of plagioclase in a coarser matrix. All samples have olivine in an advanced state of alteration, iddingsite. The geochemical analyses report that these basaltic flows contain characteristics of rift basalts. The rocks have a normative olivine values from 5.78 to 27.26 and nepheline values from 0 to 2.34. In the TAS diagram the samples straddle the join between basalt and trachy-basalt, reflecting a high K2O content. The Mg# average is 0.297, a value that suggests that the basalts do not come from a primitive magma. The basalts have high values of Ba (945-1334 ppm), Cu (54-147 ppm), and Zn (123-615 ppm). The contents of Rb (23-57 ppm), Sr (659-810 ppm), Y (26-33 ppm), Zr (148-217 ppm) and Cr (79-98 ppm) are characteristics of rift basalts. Using discrimination diagrams, the basalts plot in the field of within plate, supporting the rifting origin. Outcrops of other basalts, at about 80 to 100 km to the east of the study area, Lomas El

  16. Availability and Quantity of Human and Material Resources of Nigerian Universities' HIV Youth Friendly Centres: Implication for Policy Implementation

    Directory of Open Access Journals (Sweden)

    A.G. Akintomide

    2017-12-01

    Full Text Available The study assessed the availability and quality of human and material resources at the Campus-based Youth Friendly Centres in Southwestern Nigeria. The survey research design was adopted and the study was carried out among ten counsellors and centre coordinators of Youth Friendly Centres in four higher institutions of learning in Southwest Nigeria using interview guide and observation checklist to collect data. The result revealed that there were no enough counsellors at the YFCs and some of the counsellors available at the centres did not have enough qualification to render HIV counselling. It was also revealed that material resources were moderately available at most of the centres but not up to the require standard stipulated by the World Health Organization.

  17. Noncovalent Intermolecular Interactions in Organic Electronic Materials: Implications for the Molecular Packing vs Electronic Properties of Acenes

    KAUST Repository

    Sutton, Christopher

    2015-10-30

    Noncovalent intermolecular interactions, which can be tuned through the toolbox of synthetic chemistry, determine not only the molecular packing but also the resulting electronic, optical, and mechanical properties of materials derived from π-conjugated molecules, oligomers, and polymers. Here, we provide an overview of the theoretical underpinnings of noncovalent intermolecular interactions and briefly discuss the computational chemistry approaches used to understand the magnitude of these interactions. These methodologies are then exploited to illustrate how noncovalent intermolecular interactions impact important electronic properties-such as the electronic coupling between adjacent molecules, a key parameter for charge-carrier transport-through a comparison between the prototype organic semiconductor pentacene with a series of N-substituted heteropentacenes. Incorporating an understanding of these interactions into the design of organic semiconductors can assist in developing novel materials systems from this fascinating molecular class. © 2015 American Chemical Society.

  18. Description of Arundel Clay ornithomimosaur material and a reinterpretation of Nedcolbertia justinhofmanni as an “Ostrich Dinosaur”: biogeographic implications

    Directory of Open Access Journals (Sweden)

    Chase Doran Brownstein

    2017-03-01

    Full Text Available The fossil record of dinosaurs from the Early Cretaceous of Eastern North America is scant, especially since a few stratigraphic units from the east are fossiliferous. Among these stratigraphic units, the Arundel Clay of the eastern seaboard has produced the best-characterized dinosaur faunas known from the Early Cretaceous of Eastern North America. The diverse dinosaur fauna of the Arundel Clay has been thoroughly discussed previously, but a few of the dinosaur species originally described from the Arundel Clay are still regarded as valid genera. Much of the Arundel material is in need of review and redescription. Among the fossils of dinosaurs from this stratigraphic unit are those referred to ornithomimosaurs. Here, the researcher describes ornithomimosaur remains from the Arundel Clay of Prince George’s County, Maryland which may be from two distinct ornithomimosaur taxa. These remains provide key information on the theropods of the Early Cretaceous of Eastern North America. Recent discoveries of small theropod material from the Arundel Clay possibly belonging to ornithomimosaurs are also reviewed and described for the first time. The description of the Arundel material herein along with recent discoveries of basal ornithomimosaurs in the past 15 years has allowed for comparisons with the coelurosaur Nedcolbertia justinhofmanni, suggesting the latter animal was a basal ornithomimosaur rather than a “generalized” coelurosaur as it was originally described. Comparisons between the Arundel ornithomimosaur material and similar Asian and European specimens suggest that both extremely basal ornithomimosaurs and more intermediate or derived forms may have coexisted throughout the northern hemisphere during the Early Cretaceous.

  19. Failure of heterogeneous materials: Scaling properties of fracture surfaces and implications on models of cracks in disordered media.

    Science.gov (United States)

    Bonamy, Daniel

    2007-03-01

    While there exists a unified theoretical framework - Linear Elastic Fracture Mechanics (LEFM) - to describe the failure of homogeneous materials, understanding and modelling the mechanical properties of heterogeneous media continue to raise significant fundamental challenges. These mechanical properties, observed at the macroscopic scale, result from microscopic processes occurring at the scale of the material. To include these local processes into a statistical description constitutes then a crucial step toward the setup of predictive macroscopic models. Crack surface roughness is a consequence of these local processes. Consequently, many fractography experiments have focussed on their analysis. In this context, it was recently evidenced that, in many materials, fracture surfaces exhibit anisotropic scaling properties reminiscent to interface growth problems, fully characterized by two couples of parameters: The roughness exponents and the characteristic length-scales measured along and perpendicular to the direction of crack growth respectively. While the characteristic length-scales do depend on the considered material, the exponents are surprisingly universal: Two distinct sets of critical exponents are observed whether the surfaces are examined at scales below or above the size of the damaged zone at the crack front. Models of crack growth in disordered media are discussed at the light of these experimental observations. In particular, one can derive a model from LEFM which describe the development of crack roughness as an ``elastic'' manifold creeping in a random media. This approach captures quantitatively the experimental observations performed at length-scales above the size of the process zone. In this approach, the onset of crack propagation can be interpreted as a dynamic phase transition while sub-critical crack growth can be assimilated to thermally-assisted depinning.

  20. Probability encoding of hydrologic parameters for basalt. Elicitation of expert opinions from a panel of three basalt waste isolation project staff hydrologists

    International Nuclear Information System (INIS)

    Runchal, A.K.; Merkhofer, M.W.; Olmsted, E.; Davis, J.D.

    1984-11-01

    The present study implemented a probability encoding method to estimate the probability distributions of selected hydrologic variables for the Cohassett basalt flow top and flow interior, and the anisotropy ratio of the interior of the Cohassett basalt flow beneath the Hanford Site. Site-speciic data for these hydrologic parameters are currently inadequate for the purpose of preliminary assessment of candidate repository performance. However, this information is required to complete preliminary performance assessment studies. Rockwell chose a probability encoding method developed by SRI International to generate credible and auditable estimates of the probability distributions of effective porosity and hydraulic conductivity anisotropy. The results indicate significant differences of opinion among the experts. This was especially true of the values of the effective porosity of the Cohassett basalt flow interior for which estimates differ by more than five orders of magnitude. The experts are in greater agreement about the values of effective porosity of the Cohassett basalt flow top; their estimates for this variable are generally within one to two orders of magnitiude of each other. For anisotropy ratio, the expert estimates are generally within two or three orders of magnitude of each other. Based on this study, the Rockwell hydrologists estimate the effective porosity of the Cohassett basalt flow top to be generally higher than do the independent experts. For the effective porosity of the Cohassett basalt flow top, the estimates of the Rockwell hydrologists indicate a smaller uncertainty than do the estimates of the independent experts. On the other hand, for the effective porosity and anisotropy ratio of the Cohassett basalt flow interior, the estimates of the Rockwell hydrologists indicate a larger uncertainty than do the estimates of the independent experts

  1. Application of the iron-enriched basalt waste form for immobilizing commercial transuranic waste

    International Nuclear Information System (INIS)

    Owen, D.E.

    1981-08-01

    The principal sources of commercial transuranic (TRU) waste in the United States are identified. The physical and chemical nature of the wastes from these sources are discussed. The fabrication technique and properties of iron-enriched basalt, a rock-like waste form developed for immobilizing defense TRU wastes, are discussed. The application of iron-enriched basalt to commercial TRU wastes is discussed. Review of commercial TRU wastes from mixed-oxide fuel fabrication, light water reactor fuel reprocessing, and miscellaneous medical, research, and industrial sources, indicates that iron-enriched basalt is suitable for most types of commercial TRU wastes. Noncombustible TRU wastes are dissolved in the high temperature, oxidizing iron-enriched basalt melt. Combustible TRU wastes are immobilized in iron-enriched basalt by incinerating the wastes and adding the TRU-bearing ash to the melt. Casting and controlled cooling of the melt produces a devitrified, rock-like iron-enriched basalt monolith. Recommendations are given for testing the applicability of iron-enriched basalt to commercial TRU wastes

  2. Edentulation alters material properties of cortical bone in the human craniofacial skeleton: functional implications for craniofacial structure in primate evolution

    Science.gov (United States)

    Dechow, Paul C.; Wang, Qian; Peterson, Jill

    2011-01-01

    Skeletal adaptations to reduced function are an important source of skeletal variation and may be indicative of environmental pressures that lead to evolutionary changes. Humans serve as a model animal to investigate the effects of loss of craniofacial function through edentulation. In the human maxilla, it is known that edentulation leads to significant changes in skeletal structure such as residual ridge resorption and loss of cortical thickness. However, little is known about changes in bone tissue structure and material properties, which are also important for understanding skeletal mechanics but are often ignored. The aims of this study were to determine cortical material properties in edentulous crania and to evaluate differences with dentate crania and thus examine the effects of loss of function on craniofacial structure. Cortical bone samples from fifteen edentulous human skulls were measured for thickness and density. Elastic properties and directions of maximum stiffness were determined by using ultrasonic techniques. These data were compared to those from dentate crania reported in a previous investigation. Cortical bone from all regions of the facial skeleton of edentulous individuals is thinner than in dentate skulls. Elastic and shear moduli, and density are similar or greater in the zygoma and cranial vault of edentulous individuals, while these properties are less in the maxilla. Most cortical bone, especially in edentulous maxillae, has reduced directional orientation. The loss of significant occlusal loads following edentulation may contribute to the change in material properties and the loss of orientation over time during the normal process of bone remodeling. These results suggest that area-specific cortical microstructural changes accompany bone resorption following edentulation. They also suggest that functional forces are important for maintaining bone mass throughout the craniofacial skeleton, even in areas such as the browridges, which

  3. Global Warming Implications of the Use of By-Products and Recycled Materials in Western Australia?s Housing Sector

    OpenAIRE

    Lawania, Krishna; Sarker, Prabir; Biswas, Wahidul

    2015-01-01

    Western Australia’s housing sector is growing rapidly and around half a million houses are expected to be built by 2030, which not only will result in increased energy and resources demand but will have socio-economic impacts. Majority of Western Australians live in detached houses made of energy intensive clay bricks, which have a high potential to generate construction and demolition (C&D) waste. Therefore, there is a need to look into the use of alternative materials and construction m...

  4. Redox Variations in Early Solar System Materials and Implications for Late Stage Planetary Accretion and Planet Formation

    Science.gov (United States)

    Righter, K.

    2017-01-01

    Oxygen fugacity plays an important role in determining the detailed physical and chemical aspects of planets and their building blocks. Basic chemical properties such as the amount of oxidized Fe in a mantle (as FeO), the nature of alloying elements in the core (S, C, H, O, Si), and the solubility of various volatile elements in the silicate and metallic portions of embryos and planets can influence physical properties such as the size of the core, the liquidus and solidus of the mantle and core, and the speciation of volatile compounds contributing to atmospheres. This paper will provide an overview of the range of fO2 variation observed in primitive and differentiated materials that may have participated in accretion (cosmic dust, Star-dust and meteorites), a comparison to observations of planetary fO2 (Mercury, Mars and Earth), and a discus-sion of timing of variation of fO2 within both early and later accreted materials. This overview is meant to promote discussion and interaction between students of these two stages of planet formation to identify areas where more work is needed.

  5. Basalt models for the Mars penetrator mission: Geology of the Amboy Lava Field, California

    Science.gov (United States)

    Greeley, R.; Bunch, T. E.

    1976-01-01

    Amboy lava field (San Bernardino County, California) is a Holocene basalt flow selected as a test site for potential Mars Penetrators. A discussion is presented of (1) the general relations of basalt flow features and textures to styles of eruptions on earth, (2) the types of basalt flows likely to be encountered on Mars and the rationale for selection of the Amboy lava field as a test site, (3) the general geology of the Amboy lava field, and (4) detailed descriptions of the target sites at Amboy lava field.

  6. Deformation of poorly consolidated sediment during shallow emplacement of a basalt sill, Coso Range, California

    Science.gov (United States)

    Duffield, W.A.; Bacon, C.R.; Delaney, P.T.

    1986-01-01

    A 150-m-long, wedge-shaped unit of folded and faulted marly siltstone crops out between undeformed sedimentary rocks on the north flank of the Coso Range, California. The several-meter-thick blunt end of this wedge abuts the north margin of a basaltic sill of comparable thickness. Chaotically deformed siltstone crops out locally at the margin of this sill, and at one locality breccia pipes about one meter in diameter crosscut the sill. The sill extends about 1 km south up the paleoslope, where it merges through continuous outcrop with a lava flow that in turn extends 1.4 km to a vent area marked by more than 100 m of agglutinate and scoria. Apparently, lava extruded at this vent flowed onto unconsolidated sediments, burrowed into them, and fed a sill at about 40 m depth within the sedimentary sequence. The sill initially propagated by wedging between sedimentary beds, but eventually began to push some beds ahead of itself, forming a remarkable train of folds in the process. The sediments apparently were wet at the time of sill emplacement, because hydrothermal alteration is common near the contact between the two rock types and because the breccia pipes that crosscut the sill apparently resulted from phreatic explosions of pore water heated at the base of the cooling sill. Comparison of deformation of the host material at the Coso locality with that reportedly caused by emplacement of sills elsewhere indicates that the character of deformation differs greatly among the various localities. The specific response of host material depends upon such parameters as initial properties of magma and host material, rate of sill growth and attendant rate of strain of host material, and depth of sill emplacement. Some properties may change considerably during an intrusive-deformational episode, thus complicating accurate reconstruction of such an event. ?? 1986 Springer-Verlag.

  7. Spiral-type heteropolyhedral coordination network based on single-crystal LiSrPO4: implications for luminescent materials.

    Science.gov (United States)

    Lin, Chun Che; Shen, Chin-Chang; Liu, Ru-Shi

    2013-11-04

    Novel structures of luminescent materials, which are used as light sources for next-generation illumination, are continuously being improved for use in white-light-emitting diodes. Activator-doped known structures are reported as habitual down-conversion phosphors in solid-state lightings and displays. Consequently, the intrinsic qualities of the existent compounds produce deficiencies that limit their applications. Herein we report a spiral-network single-crystal orthophosphate (LiSrPO4) prepared in a platinum crucible with LiCl flux through crystal-growth reactions of SrCl2 and Li3PO4 in air. It crystallizes in a hexagonal system with a=5.0040(2) and c=24.6320(16) Å, V=534.15(5) Å(3), and Z=6 in the space group P6(5). The unit cell is comprised of LiO4 and PO4 tetrahedrons that form a three-dimensional LiPO4(2-) anionic framework with a helical channel structure along the c axis in which the Sr(2+) cation is accommodated. The optical band gap of this composition is about 3.65 eV, as determined by using UV/Vis absorption and diffuse reflection spectra. We used the crystal-growth method to synthesize blue- and red-emitting crystals that exhibited pure color, low reabsorption, a large Stokes shift, and efficient conversion of ultraviolet excitation light into visible light. Emphasis was placed on the development of gratifying structure-related properties of rare-earth luminescent materials and their applications. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. The Auckland Volcanic Field - a basaltic field showing random behavior?

    Science.gov (United States)

    Le Corvec, N.; Rowland, J. V.; Lindsay, J. M.

    2012-04-01

    Basaltic monogenetic volcanism is a worldwide phenomenon typically producing fields of volcanic centers that increase in number with time. The process of field growth is not constant but punctuated by single eruptions, flare-ups and hiatuses. The development of a volcanic field involves physical processes that occur in the mantle, where batches of basaltic magma originate, and within the intervening lithosphere through which magma is transferred to the surface. The spatial and temporal distribution of volcanic centers within such volcanic fields results from, and thus may provide insights to, these physical processes (e.g., magma production, tectonic controls), thereby aiding in our understanding of a volcanic field's future development. The Auckland Volcanic Field (AVF), which lies in the most populated area of New Zealand, comprises 50 volcanic centers and produced its last eruption ~600 years ago. A recent study has provided a relative chronology of the entire sequence of eruptions, which is here used together with the spatial distribution of volcanic centers to investigate the evolution of the field in time and space. Two methods were used: 1) the Poisson Nearest Neighbor (PNN) analysis which evaluates the spatial distribution of a natural population over the spatial distribution of a statistical random model, the Poisson model; and 2) the Voronoi analysis which evaluates the spatial characteristics of each volcanic center by dividing a region (i.e., the volcanic field) into a set of polygons. The results of the PNN analysis show that the temporal evolution of the spatial distribution of the volcanic centers within the AVF follows the Poisson model, therefore they cannot be used to extrapolate the future evolution of the volcanic field. The preliminary results of the Voronoi analysis show in combination with the geochemical signatures from some volcanic centers a possible zonation within the source region, and/or the magmas may be variably affected on their way

  9. Submarine basaltic fountain eruptions in a back-arc basin during the opening of the Japan Sea

    Science.gov (United States)

    Hosoi, Jun; Amano, Kazuo

    2017-11-01

    Basaltic rock generated during the middle Miocene opening of the Japan Sea, is widely distributed on the back-arc side of the Japanese archipelago. Few studies have investigated on submarine volcanism related to opening of the Japan Sea. The present study aimed to reconstruct details of the subaqueous volcanism that formed the back-arc basin basalts (BABB) during this event, and to discuss the relationship between volcanism and the tectonics of back-arc opening, using facies analyses based on field investigation. The study area of the southern Dewa Hills contains well-exposed basalt related to the opening of the Japan Sea. Five types of basaltic rock facies are recognized: (1) coherent basalt, (2) massive platy basalt, (3) jigsaw-fit monomictic basaltic breccia, (4) massive or stratified coarse monomictic basaltic breccia with fluidal clasts, and (5) massive or stratified fine monomictic basaltic breccia. The basaltic rocks are mainly hyaloclastite. Based on facies distributions, we infer that volcanism occurred along fissures developed mainly at the center of the study area. Given that the rocks contain many fluidal clasts, submarine lava fountaining is inferred to have been the dominant eruption style. The basaltic rocks are interpreted as the products of back-arc volcanism that occurred by tensional stress related to opening of the Japan Sea, which drove strong tectonic subsidence and active lava fountain volcanism.

  10. Thermally Bonded PET–Basalt Sandwich Composites for Heat Pipeline Protection: Preparation, Stab Resisting, and Thermal-Insulating Properties

    Directory of Open Access Journals (Sweden)

    Ting-Ting Li

    2018-03-01

    Full Text Available In order to solve the cost and bulky problems of buried thermal pipeline insulating materials, this study adopts basalt fabric and low-melting PET nonwoven to construct low-cost and light-weight pipeline thermal-insulating composites after needle punching and thermal bonding processes. Research result shows that thermal-bonded temperature affected the stab resistance and burst energy more significantly. As thermal-bonded temperature increased, knife resistance and spike resistance presented the upward and then downward trends, but the burst energy gradually decreased. Yarn pull-out result shows that the enhancement of stab resistance of intra-/inter-thermal-bonded structure resulted from the increment in the coefficient of friction between yarns. When PET–basalt sandwich composites were thermal-bonded at 140 °C for 5 min, the maximum knife and spike resistance were 147.00 N (1.99 J and 196.30 N (1.11 J, respectively, and burst energy was 4.79 J, thermal conductivity reduced to 0.0073 W/(m∙K. The resultant thermally bonded sandwich composites can be used as thermal-insulating protection for buried thermal pipeline.

  11. Sourcing the megalithic stones of Nan Madol : an XRF study of architectural basalt stone from Pohnpei, Federated States of Micronesia

    International Nuclear Information System (INIS)

    McCoy, M.D.; Athens, J.S.

    2012-01-01

    Nan Madol is a massive 81 hectare prehistoric administrative and ceremonial complex made up of 93 constructed islets on the high volcanic island of Pohnpei. Built between Ad 900 and 1650 over earlier settlement remains along the southern coast of Temwen Island within the fringing reef, the site is noted for its distinctive use of columnar basalt and large boulders. XRF analysis presented here suggests the site's builders favoured columnar basalt from the island's main shield building stage (7-8 mya) over post-shield material. Boulders incorporated in the architecture are primarily from post-shield stage Temwen Island but supplemented by some main shield boulders from mainland Pohnpei. Preliminary findings further suggest that there were shifts in the relative frequency of quarries used to construct different structures. These shifts could relate to exhaustion of accessible stone from specific sources or perhaps changing preferences for stone from different sources due to social or political imperatives. (author). 23 refs., 6 figs., 4 tabs.

  12. Petrological, magnetic and chemical properties of basalt dredged from an abyssal hill in the North-east pacific

    Science.gov (United States)

    Luyendyk, B.P.; Engel, C.G.

    1969-01-01

    OVER the years, samples of basalt from the oceanic crust have been taken mainly from seamounts, fracture zones and ridge and rise crests1-6, and rarely from the vast fields of abyssal hills which cover a large part of the deep-sea floor. The basalt sampled from the deeper regions of the oceanic crust (for example, on fault scarps) is a distinct variety of tholeiitic basalt, while alkali basalt is restricted to the volcanic edifices4. Oceanic tholeiitic basalt differs from alkali basalt and continental tholeiite chiefly in having a relatively low percentage of K2O (0.2 weight per cent)4. Some authors have speculated that this type of tholeiitic basalt is the major extrusion from the upper mantle and constitutes the predominant rock type in the upper oceanic crust. ?? 1969 Nature Publishing Group.

  13. Material and energy balances of an integrated biological hydrogen production and purification system and their implications for its potential to reduce greenhouse gas emissions.

    Science.gov (United States)

    Fukushima, Yasuhiro; Huang, Yu-Jung; Chen, Jhen-Wei; Lin, Hung-Chun; Whang, Liang-Ming; Chu, Hsin; Lo, Young-Chong; Chang, Jo-Shu

    2011-09-01

    The materials and energy in an integrated biological hydrogen production and purification system involving hydrolysis, dark fermentation, photo fermentation, CO2 fixation and anaerobic digestion are balanced by integrating the results from multiple experiments, simulations and the literature. The findings are two fold. First, using 1000 kg rice straw as a substrate, 19.8 kg H2 and 138.0 kg CH4 are obtained. The net energy balance (NEB) and net energy ratio (NER) are -738.4 kWh and 77.8%, respectively, both of which imply an unfavorable energy production system. Opportunities to improve the performance particularly lie in the photo fermentation process. Second, greenhouse gas emissions are evaluated for various options. The results were comparable with the emission inventory of electricity generated from fossil fuels. NEB and NER under a zero-carbon-emission constraint were discussed in detail to clarify completely the implications of the energy and material balances on greenhouse gas emissions. Copyright © 2011 Elsevier Ltd. All rights reserved.

  14. Mineralogy, Petrology and Oxygen Fugacity of the LaPaz Icefield Lunar Basaltic Meteorites and the Origin of Evolved Lunar Basalts

    Science.gov (United States)

    Collins, S. J.; Righter, K.; Brandon, A. D.

    2005-01-01

    LAP 02205 is a 1.2 kg lunar mare basalt meteorite found in the Lap Paz ice field of Antarctica in 2002 [1]. Four similar meteorites were also found within the same region [1] and all five have a combined mass of 1.9 kg (LAP 02224, LAP 02226, LAP 02436 and LAP 03632, hereafter called the LAP meteorites). The LAP meteorites all contain a similar texture, mineral assemblage, and composition. A lunar origin for these samples comes from O isotopic data for LAP 02205 [1], Fe/Mn ratios of pyroxenes [1-5], and the presence of distinct lunar mineralogy such as Fe metal and baddeleyite. The LAP meteorites may represent an area of the Moon, which has never been sampled by Apollo missions, or by other lunar meteorites. The data from this study will be used to compare the LAP meteorites to Apollo mare basalts and lunar basaltic meteorites, and will ultimately help to constrain their origin.

  15. The Supercourse of fisheries: importance of sharing educational materials and implications for cancer and chronic disease research.

    Science.gov (United States)

    Linkov, Faina; Hussein, Izzeldin S; Taioli, Emanuela; Laporte, Ronald; Al-Oufi, Hamed Said

    2009-01-01

    Epidemiologic research has demonstrated that fish is an important component of human nutrition. Existing information for the public about the benefits vs dangers of fish consumption is often contradictory and unclear. Education in the field of human nutrition, especially in the area of fish consumption could be markedly enhanced if there were better mechanisms for the development of customized high quality, low cost educational lectures Researchers from the Department of Epidemiology, University of Pittsburgh, in collaboration with the members of the Global Health Network Supercourse project are developing a library of lectures on nutrition, environmental health, and fisheries, for the use and share among the scientists of the world. With the growing demand for environmental health/nutrition awareness, there is an escalating demand for easily accessible and inexpensive teaching materials on nutritional information, including fish and fisheries. The Supercourse has a network of 45,000 faculty members from 171 countries who have contributed more than 3400 public health lectures, providing forum for sharing the latest research developments in the areas of nutrition. This article outlines the importance of creating easily accessible educational modules on the issues of nutrition, environmental health challenges, and fisheries.

  16. A Breccia of Ureilitic and C2 Carbonaceous Chondrite Materials from Almahata Sitta: Implications for the Regolith of Urelitic Asteroids

    Science.gov (United States)

    Goodrich, C. A.; Fioretti, A. M.; Zolensky, M.; Fries, M.; Shaddad, M.; Kohl, I.; Young, E.; Jenniskens, P.

    2017-01-01

    The Almahata Sitta (AhS) polymict ureilite is the first meteorite to originate from a spectrally classified asteroid (2008 TC3) [1-3], and provides an unprecedented opportunity to correlate properties of meteorites with those of their parent asteroid. AhS is also unique because its fragments comprise a wide variety of meteorite types. Of approximately140 stones studied to-date, 70% are ureilites (carbon-rich ultramafic achondrites) and 30% are various types of chondrites [4,5]. None of these show contacts between ureilitic and chondritic lithologies. It has been inferred that 2008 TC3 was loosely aggregated, so that it disintegrated in the atmosphere and only its most coherent clasts fell as individual stones [1,3,5]. Understanding the structure and composition of this asteroid is critical for missions to sample asteroid surfaces. We are studying [6] the University of Khartoum collection of AhS [3] to test hypotheses for the nature of 2008 TC3. We describe a sample that consists of both ureilitic and chondritic materials.

  17. Underground engineering at the Basalt Waste Isolation Project

    International Nuclear Information System (INIS)

    1987-01-01

    A special task group was organized by the US National Committee for Rock Mechanics and the Board on Radioactive Waste Management of the National Research Council to address issues relating to the geotechnical site characterization program for an underground facility to house high-level radioactive waste of the Basalt Waste Isolation Project (BWIP). Intended to provide an overview of the geotechnical program, the study was carried out by a task group consisting of ten members with expertise in the many disciplines required to successfully complete such a project. The task group recognized from the outset that the short time frame of this study would limit its ability to address all geotechnical issues in detail. Geotechnical issues were considered to range from specific technical aspects such as in-situ testing for rock mass permeability; rock hardness testing in the laboratory; or geologic characterizations and quantification of joints, to broader aspects of design philosophy, data collection, and treatment of uncertainty. The task group chose to focus on the broader aspects of underground design and construction, recognizing that the BWIP program utilizes a peer review group on a regular basis which reviews the specific technical questions related to geotechnical engineering. In this way, it was hoped that the review provided by the task group would complement those prepared by the BWIP peer review group

  18. Petrology of basaltic and monomineralic soil fragments from the Sea of Fertility.

    Science.gov (United States)

    Bence, A. E.; Holzwarth, W.; Papike, J. J.

    1972-01-01

    Basaltic and monomineralic fragments from the 150-425 micron size fractions of the Luna 16 core obtained from the Sea of Fertility were studied by optical petrographic, electron microprobe, and single-crystal X-ray diffraction techniques. Three textural varieties were identified in the basalts (intersertal, subophitic, and recrystallized). These textures, the assemblages, and individual mineral compositions (especially pyroxenes) indicate that these basalts crystallized under conditions very similar to those from Apollo 11. The pyroxenes have slightly lower Ti/Al (atomic) ratios than the Apollo 11 pyroxenes. We interpret the presence of octahedral Al as being due to the low TiO2/Al2O3 (weight %) ratio in the bulk rock. All observations made on the fine-grained basalt fragments are consistent with a rapid, near-surface, one-stage crystallization history.

  19. Basalt Related to Lunar Mg-Suite Plutonic Rocks: A Fragment in Lunar Meteorite ALH 81005

    Science.gov (United States)

    Treiman, A. H.; Gross, J.

    2013-09-01

    We report on a basalt clast, in meteorite ALH 81005, which appears to be from a volcanic equivalent of an Mg-suite plutonic rock. Its mineral compositions, mineral proportions, and trace minerals are like those of Mg-norites.

  20. Basalt microlapilli in deep sea sediments of Indian Ocean in the vicinity of Vityaz fracture zone

    Digital Repository Service at National Institute of Oceanography (India)

    Nath, B.N.; Iyer, S.D

    Two cores recovered from the flanks of Mid-India oceanic ridge in the vicinity of Vityaz fracture zone consist of discrete pyroclastic layers at various depths. These layers are composed of coarse-grained, angular basaltic microlapilli in which...

  1. Coupled geomechanical/hydrological modeling: an overview of basalt waste isolation project studies

    International Nuclear Information System (INIS)

    Baca, R.G.; Case, J.B.; Patricio, J.G.

    1980-07-01

    Basalt Waste Isolation Project investigations of the Columbia River basalts are multi-disciplinary in nature with a broad scope spanning such areas as geology, seismology, geochemistry, hydrology, rock mechanics, and many other disciplines as well. In this paper, an overview is presented which surveys recent work on numerical modeling of geomechanical and hydrological processes in a basalt rock environment. A major objective of the ongoing numerical modeling work is to establish a predictive technology base with which to: interpret the interrelationships between geomechanical behavior of rock media, the natural hydrologic phenomena, and repository conditions; evaluate the effectiveness of preconceptual repository designs and assist in the design of in situ field testing; and assess the waste isolation capability of candidate host rocks within the Columbia River basalts. To accomplish this objective, a systems approach has been adopted which is based on the use of digital simulation models

  2. Oxygen fugacity of basaltic magmas and the role of gas-forming elements

    Science.gov (United States)

    Sato, M.

    1978-01-01

    It is suggested that major variations in the relative oxygen fugacity of a basaltic magma are caused primarily by gas-forming elements, especially carbon and hydrogen. According to this theory, carbon, present in the source region of a basaltic magma, reduces the host magma during ascent, as isothermally carbon becomes more reducing with decreasing pressure. For an anhydrous magma such as lunar basalts, this reduction continues through the extrusive phase and the relative oxygen fugacity decreases rapidly until buffered by the precipitation of a metallic phase. For hydrous magmas such as terrestrial basalts, reduction by carbon is eventually superceded by oxidation due to loss of H2 generated by the reaction of C with H2O and by thermal dissociation of H2O. The relative oxygen fugacity of a hydrous magma initially decreases as a magma ascends from the source region and then increases until magnetite crystallization curbs the rising trend of the relative oxygen fugacity.

  3. A note on sulphide-oxide mineralisation in Carlsberg Ridge basalts

    Digital Repository Service at National Institute of Oceanography (India)

    Banerjee, R.; Iyer, S.D.

    Pillow basalts from the Carlsberg Ridge at 3 degrees 35'N contain disseminated chalcopyrite, pyrite, and magnetite. The euhedral shape of the pyrite grains indicate them to be early formed and grown unobstructed while magnetite occurs as skeletal...

  4. Mineral chemistry of Carlsberg Ridge basalts at 3 degrees 35'- 3 degrees 41' N

    Digital Repository Service at National Institute of Oceanography (India)

    Iyer, S.D.; Banerjee, R.

    (approximately 91 mole %) are few and rarely zoned. The composition of plagioclase and olivine indicate low pressure equilibrium crystallization. The basalts were probably derived through fractional crystallization at shallow depths under low partial melting...

  5. Ambient noise tomography reveals basalt and sub-basalt velocity structure beneath the Faroe Islands, North Atlantic

    Science.gov (United States)

    Sammarco, Carmelo; Cornwell, David G.; Rawlinson, Nicholas

    2017-11-01

    Ambient noise tomography is applied to seismic data recorded by a portable array of seismographs deployed throughout the Faroe Islands in an effort to illuminate basalt sequences of the North Atlantic Igneous Province, as well as underlying sedimentary layers and Precambrian basement. Rayleigh wave empirical Green's functions between all station pairs are extracted from the data via cross-correlation of long-term recordings, with phase weighted stacking implemented to boost signal-to-noise ratio. Dispersion analysis is applied to extract inter-station group travel-times in the period range 0.5-15 s, followed by inversion for period-dependent group velocity maps. Subsequent inversion for 3-D shear wave velocity reveals the presence of significant lateral heterogeneity (up to 25%) in the crust. Main features of the final model include: (i) a near-surface low velocity layer, interpreted to be the Malinstindur Formation, which comprises subaerial compound lava flows with a weathered upper surface; (ii) a sharp velocity increase at the base of the Malinstindur Formation, which may mark a transition to the underlying Beinisvørð Formation, a thick laterally extensive layer of subaerial basalt sheet lobes; (iii) a low velocity layer at 2.5-7.0 km depth beneath the Beinisvørð Formation, which is consistent with hyaloclastites of the Lopra Formation; (iv) an upper basement layer between depths of 5-9 km and characterized by S wave velocities of approximately 3.2 km/s, consistent with low-grade metamorphosed sedimentary rocks; (v) a high velocity basement, with S wave velocities in excess of 3.6 km/s. This likely reflects the presence of a crystalline mid-lower crust of Archaean continental origin. Compared to previous interpretations of the geological structure beneath the Faroe Islands, our new results point to a more structurally complex and laterally heterogeneous crust, and provide constraints which may help to understand how continental fragments are rifted from the

  6. Terrigenous material supply to the Peruvian central continental shelf (Pisco, 14° S) during the last 1000 years: paleoclimatic implications

    Science.gov (United States)

    Briceño-Zuluaga, Francisco Javier; Sifeddine, Abdelfettah; Caquineau, Sandrine; Cardich, Jorge; Salvatteci, Renato; Gutierrez, Dimitri; Ortlieb, Luc; Velazco, Federico; Boucher, Hugues; Machado, Carine

    2016-03-01

    In the eastern Pacific, lithogenic input to the ocean responds to variations in the atmospheric and oceanic system and their teleconnections over different timescales. Atmospheric (e.g., wind fields), hydrological (e.g., fresh water plumes) and oceanic (e.g., currents) conditions determine the transport mode and the amount of lithogenic material transported from the continent to the continental shelf. Here, we present the grain size distribution of a composite record of two laminated sediment cores retrieved from the Peruvian continental shelf that record the last ˜ 1000 years at a sub-decadal to centennial time-series resolution. We propose novel grain size indicators of wind intensity and fluvial input that allow reconstructing the oceanic-atmospheric variability modulated by sub-decadal to centennial changes in climatic conditions. Four grain size modes were identified. Two are linked to aeolian inputs (M3: ˜ 54; M4: ˜ 91 µm on average), the third is interpreted as a marker of sediment discharge (M2: ˜ 10 µm on average), and the last is without an associated origin (M1: ˜ 3 µm). The coarsest components (M3 and M4) dominated during the Medieval Climate Anomaly (MCA) and the Current Warm Period (CWP) periods, suggesting that aeolian transport increased as a consequence of surface wind stress intensification. In contrast, M2 displays an opposite behavior, exhibiting an increase in fluvial terrigenous input during the Little Ice Age (LIA) in response to more humid conditions associated with El Niño-like conditions. Comparison with other South American paleoclimate records indicates that the observed changes are driven by interactions between meridional displacement of the Intertropical Convergence Zone (ITCZ), the South Pacific Subtropical High (SPSH) and Walker circulation at decadal and centennial timescales.

  7. Terrigeneous material supply to the Peruvian central continental shelf (Pisco 14° S) during the last 1100 yr: paleoclimatic implications

    Science.gov (United States)

    Briceño Zuluaga, F.; Sifeddine, A.; Caquineau, S.; Cardich, J.; Salvatteci, R.; Gutierrez, D.; Ortlieb, L.; Velazco, F.; Boucher, H.; Machado, C.

    2015-07-01

    In the Eastern Pacific, lithogenic input to the ocean is a response of the atmospheric and ocean system variability and their teleconnections over different timescales. Atmospheric (e.g., wind fields, precipitation), hydrological (e.g., fresh water plumes) and oceanic (e.g., currents) conditions determine the transport mode and the amount of lithogenic material transported from the continent to the continental shelf. Here, we present the grain size distribution of a composite record of two laminated sediment cores retrieved in the Peruvian continental shelf, covering the last ~1100 yr at sub-decadal to centennial time-series resolution. We then discuss the paleo-environmental significance and the climatic mechanisms involved. Four grain size modes were identified. Two are linked to aeolian inputs (M3: 53.0 μm and M4: 90.8 μm on average), the third is interpreted as a marker of sediment discharge (M2: 9.4 μm on average), and the last is without an associated origin (M1: ~3 μm). The coarsest components (M3 and M4) dominated during the Medieval Climate Anomaly (MCA) and Current Warm Period (CWP) periods, suggesting that aeolian transport increased as consequence of wind stress intensification. In contrast, M2 displays an opposite behavior, exhibiting an increase in fluvial terrigenous input during the Little Ice Age (LIA), in response to more humid conditions. Comparison with other South American paleoclimate records indicates that the observed changes are driven by interactions between meridional displacement of the Intertropical convergence zone (ITCZ) and of the South Pacific Sub-tropical High (SPSH) at decadal and centennial time scales.

  8. Physical abrasion of mafic minerals and basalt grains: application to Martian aeolian deposits

    Science.gov (United States)

    Cornwall, Carin; Bandfield, Joshua L.; Titus, Timothy N.; Schreiber, B. C.; Montgomery, D.R.

    2015-01-01

    Sediment maturity, or the mineralogical and physical characterization of sediment deposits, has been used to locate sediment source, transport medium and distance, weathering processes, and paleoenvironments on Earth. Mature terrestrial sands are dominated by quartz, which is abundant in source lithologies on Earth and is physically and chemically stable under a wide range of conditions. Immature sands, such as those rich in feldspars or mafic minerals, are composed of grains that are easily physically weathered and highly susceptible to chemical weathering. On Mars, which is predominately mafic in composition, terrestrial standards of sediment maturity are not applicable. In addition, the martian climate today is cold, dry and sediments are likely to be heavily influenced by physical weathering rather than chemical weathering. Due to these large differences in weathering processes and composition, martian sediments require an alternate maturity index. Abrason tests have been conducted on a variety of mafic materials and results suggest that mature martian sediments may be composed of well sorted, well rounded, spherical basalt grains. In addition, any volcanic glass present is likely to persist in a mechanical weathering environment while chemically altered products are likely to be winnowed away. A modified sediment maturity index is proposed that can be used in future studies to constrain sediment source, paleoclimate, mechanisms for sediment production, and surface evolution. This maturity index may also provide details about erosional and sediment transport systems and preservation processes of layered deposits.

  9. Geomechanics characterization of a proposed nuclear waste repository site in basalt

    International Nuclear Information System (INIS)

    Kim, K.; McCabe, W.M.

    1984-01-01

    A thorough evaluation of the geologic material being considered must be conducted to determine the feasibility of constructing a large-scale underground facility in a deep geologic formation. The design and construction of a nuclear waste repository in basalt, due to the unprecedented nature of the project, adds significantly to the need for thoroughness of this evaluation and mandates that geoengineering data and analysis be of the highest quality. The investigations required to collect the data encompass in situ measurements and observations, as well as laboratory and field tests. Mathematical (numerical) models, which are required to predict the long-term performance of the repository structure, must be developed to evaluate rock mass behavior at canister, room, and repository scale and eventually must be validated through in situ tests and monitoring. The information generated from these geomechanics investigations is essential for assessing site suitability and will be utilized in the development of the repository design, the engineered barrier design, and the evaluation of repository performance

  10. Permeameter studies of water flow through cement and clay borehole seals in granite, basalt and tuff

    Energy Technology Data Exchange (ETDEWEB)

    South, D.L.; Daemen, J.J.K.

    1986-10-01

    Boreholes near a repository must be sealed to prevent rapid migration of radionuclide-contaminated water to the accessible environment. The objective of this research is to assess the performance of borehole seals under laboratory conditions, particularly with regard to varying stress fields. Flow through a sealed borehole is compared with flow through intact rock. Cement or bentonite seals have been tested in granite, basalt, and welded tuff. The main conclusion is that under laboratory conditions, existing commercial materials can form high quality seals. Triaxial stress changes about a borehole do not significantly affect seal performance if the rock is stiffer than the seal. Temperature but especially moisture variations (drying) significantly degrade the quality of cement seals. Performance partially recovers upon resaturation. A skillfully sealed borehole may be as impermeable as the host rock. Analysis of the influence of relative seal-rock permeabilities shows that a plug with permeability one order of magnitude greater than that of the rock results in a flow increase through the hole and surrounding rock of only 1-1/2 times compared to the undisturbed rock. Since a borehole is only a small part of the total rock mass, the total effect is even less pronounced. The simplest and most effective way to decrease flow through a rock-seal system is to increase the seal length, assuming it can be guaranteed that no dominant by-pass flowpath through the rock exists.

  11. Perspectives on Ocean Ridge Basalts from the Segment to the Global Scale

    OpenAIRE

    Gale, Allison

    2012-01-01

    This study addresses the influences on ridge basalt chemistry, through analysis of their major and trace element and isotopic composition at scales ranging from individual ridge segments to the entire length of the ridge system. Local-scale studies of basalts along the Mid-Atlantic Ridge shed light on crustal accretion at slow-spreading ridges, and on the nature of plume-ridge interaction in this region. We show that segments must have multiple supplies of magma delivered along their length, ...

  12. Paleomagnetism of late Archaean flood basalt terrains : implications for early Earth geodynamics and geomagnetism

    NARCIS (Netherlands)

    Strik, G.H.M.A.

    2004-01-01

    Palaeomagnetic studies are e.g. important for demonstrating and quantifying horizontal movement and rotation of pieces of the Earth's crust. The constant movement and recycling of plates, in other words plate tectonics, is an important mechanism for the Earth to lose its heat. It is generally

  13. Palaeomagnetism of late Archaean flood basalt terrains : implications for early Earth geodynamics and geomagnetism

    NARCIS (Netherlands)

    Strik, Gerardus Henricus Martina Anna

    2004-01-01

    Palaeomagnetic studies are e.g. important for demonstrating and quantifying horizontal movement and rotation of pieces of the Earth's crust. The constant movement and recycling of plates, in other words plate tectonics, is an important mechanism for the Earth to lose its heat. It is generally

  14. Experimental study on the impact-induced seismic wave propagating through granular materials: Implications for a future asteroid mission

    Science.gov (United States)

    Yasui, M.; Matsumoto, E.; Arakawa, M.; Matsue, K.; Kobayashi, N.

    2014-07-01

    almost consistent with that of McGarr et al. (1969), 0.39-1.62. We can conclude that I/I_p is independent of the impact velocity. Implications for planetary exploration: According to the previous results, we can discuss the sensitivity of the seismometer to detect the seismic wave induced by an artificial impactor on asteroids. We calculated the maximum acceleration on asteroids with two different sizes, such as the sizes of Eros and 1999JU3, by assuming that the projectile made of copper with a mass of 2 kg impacted at 2 km/s. In this calculation, we used the crater scaling law and the attenuation equation of g_max obtained in our study. As a result, the seismometer could detect the seismic wave only around the crater cavity on an Eros-sized asteroid while it could detect the wave globally on a 1999JU3-sized asteroid.

  15. Mineralogy, geochemistry and expansion testing of an alkali-reactive basalt from western Anatolia, Turkey

    International Nuclear Information System (INIS)

    Copuroglu, Oguzhan; Andic-Cakir, Ozge; Broekmans, Maarten A.T.M.; Kuehnel, Radko

    2009-01-01

    In this paper, the alkali-silica reaction performance of a basalt rock from western Anatolia, Turkey is reported. It is observed that the rock causes severe gel formation in the concrete microbar test. It appears that the main source of expansion is the reactive glassy phase of the basalt matrix having approximately 70% of SiO 2 . The study presents the microstructural characteristics of unreacted and reacted basalt aggregate by optical and electron microscopy and discusses the possible reaction mechanism. Microstructural analysis revealed that the dissolution of silica is overwhelming in the matrix of the basalt and it eventually generates four consequences: (1) Formation of alkali-silica reaction gel at the aggregate perimeter, (2) increased porosity and permeability of the basalt matrix, (3) reduction of mechanical properties of the aggregate and (4) additional gel formation within the aggregate. It is concluded that the basalt rock is highly prone to alkali-silica reaction. As an aggregate, this rock is not suitable for concrete production.

  16. Sulfur and iron speciation in gas-rich impact-melt glasses from basaltic shergottites determined by microXANES

    Energy Technology Data Exchange (ETDEWEB)

    Sutton, S.R.; Rao, M.N.; Nyquist, L.E. (UofC); (Johnson Space Center)

    2008-04-28

    determine sulfur speciation (sulfide, sulfate or elemental sulfur) in these glasses, Gooding et al. and Burgess et al. carried out vacuum pyrolysis experiments on these GRIM glasses (also called Lith C) using quadrupole mass-spectrometric methods. They found that the evolved S-bearing gases from these samples consisted of both SO{sub 2} (from sulfate) and H{sub 2}S (from sulfide) in varying proportions. However, as mass-spectrometric studies do not provide details about spatial association of these S-species in these samples, we have studied the spatial distribution of sulfides and sulfates in GRIM glasses using sulfur K micro-XANES techniques in the present study. The microscale speciation of S may have important implications for the Rb-Sr isotope systematics of EET79001 Lith C glasses. In reference to oxidative weathering of surface basalts on Mars yielding secondary iron sulfates, Solberg and Burns examined a GRIM glass in EET79001 by Moessbauer spectroscopic techniques and showed that the percentage of Fe{sup 3+} in Lith C is <2%. They suggested that the Lith C contains very little Fe{sup 3+} despite the occurrence of oxidized sulfate in them, indicating that the conditions leading to the formation of these glasses were insufficiently oxidizing to produce Fe{sup 3+} from Fe{sup 2+} in these glasses. To understand the implications of these observations for the formation of the GRIM glasses, we determined the oxidation state of Fe in the GRIM glasses using Fe K micro-XANES techniques. The S and Fe K micro-XANES measurements were performed on thin sections from EET79001: 506 from Lith A and 507 from Lith B.

  17. Relict olivine grains, chondrule recycling, and implications for the chemical, thermal, and mechanical processing of nebular materials

    Science.gov (United States)

    Ruzicka, Alex; Floss, Christine; Hutson, Melinda

    2008-11-01

    similar, refractory melts under reducing conditions; relict Mg-olivine and isolated forsterite grains were thus derived from type I chondrules. Olivine in type II chondrules, including normal grains and ferroan overgrowths on relict Mg-olivine, crystallized from more volatile-rich, oxidized, and relatively unfractionated melts. Relict dusty olivine grains in type I chondrules were derived from type II chondrules during incomplete melting episodes involving reduction and some vaporization, with clear (non-dusty) grains in dusty olivine-bearing chondrules crystallizing from the reduced and partly vaporized melts. Melt compositions parental to normal olivine grains in type I and II chondrules are systematically enriched in refractory elements compared to bulk chondrule compositions, implying that chondrules often experienced open-system exchange with more volatile-rich surroundings after some olivine had crystallized, possibly while the chondrules were still partly molten. Type II chondrules could have been derived from type I chondrules by the addition of relatively volatile-rich material, followed by re-melting and little evaporation under oxidizing conditions. In contrast, type I chondrules could have been derived from type II chondrules by re-melting involving more-or-less evaporation under reducing conditions. Chemical, oxygen isotope, and petrographic data are best accommodated by a model in which there were several (>2-3, sometimes ⩾4-5) melting episodes for most chondrules in ordinary chondrites.

  18. High-pressure phase relation of KREEP basalts: A clue for finding the lost Hadean crust?

    Science.gov (United States)

    Gréaux, Steeve; Nishi, Masayuki; Tateno, Shigehiko; Kuwayama, Yasuhiro; Hirao, Naohisa; Kawai, Kenji; Maruyama, Shigenori; Irifune, Tetsuo

    2018-01-01

    The phase relations, mineral chemistry and density of KREEP basalt were investigated at pressures of 12-125 GPa and temperatures up to 2810 K by a combination of large volume multi-anvil press experiments and in situ synchrotron X-ray diffraction measurements in a laser-heated diamond anvil cell. Our results showed that grossular-rich majorite garnet, liebermannite and Al-bearing stishovite are dominant in the upper-to-middle part of the upper mantle while in the lowermost transition zone a dense Ti-rich CaSiO3 perovskite exsoluted from the garnet, which becomes more pyropic with increasing pressure. At lower mantle conditions, these minerals transform into an assemblage of bridgmanite, Ca-perovskite, Al-stishovite, the new aluminium-rich (NAL) phase and the calcium-ferrite type (CF) phase. At pressures higher than 50 GPa, NAL phase completely dissolved into the CF phase, which becomes the main deposit of alkali metals in the lower mantle. The density of KREEP estimated from phase compositions obtained by energy dispersive X-ray spectroscopy (EDS) in scanning (SEM) and transmission (TEM) electron microscopes, was found substantially denser than pyrolite suggesting that the Earth primordial crust likely subducted deep into the Earth's mantle after or slightly before the final solidification of magma ocean at 4.53 Ga. Radiogenic elements U, Th and 40K which were abundant in the final residue of magma ocean were brought down along the subduction of the primordial crust and generate heat by decay after the settlement of the primordial crust on top of the CMB, suggesting the non-homogeneous distribution of radiogenic elements in the Hadean mantle with implications for the thermal history of the Earth.

  19. Evidence for intense hydrothermal alteration associated with flood basalt volcanism during the birth of the Azores Plateau

    Science.gov (United States)

    Bach, W.; Busch, A.; Genske, F. S.; Beier, C.; Krumm, S.

    2017-12-01

    A stratigraphic section comprising >1000 m of upper crust in the Princess Alice Bank (PAB) of the western Azores Plateau was sampled during RV Meteor cruise M128 in July of 2016, using the ROV MARUM Quest 4000m. Twenty-two samples were recovered between 2484 and 1439 m water depth from the southfacing footwall of the Master fault bounding a prominent NW-SE striking rift zone within the PAB. Our geochemical and petrographic results show that virtually all samples are pervasively altered. The deeper part of the section (up to 1750 m water depth) was altered under greenschist-facies conditions to assemblages that include epidote, chlorite, albite, titanite, and actinolite. These rocks show 87Sr/86Sr values between 0.7036 and 0.7050. The topmost section was altered under lower metamorphic grades to chlorite/smectite-quartz-anatase. These rocks show severe losses of Ca and Sr, and gains in Mg, Li, and B, with 87Sr/86Sr ratios as high as 0.708. These geochemical signatures indicate an intensity of hydrothermal exchange between seawater and crust that is unmatched by any in situ section of upper ocean crust sampled by ocean drilling to date. Oxygen isotope data for epidote-calcite veins indicate temperatures of 250-300°C. Later quartz gives about 200°C. The implications of the intense hydrothermal alteration for crust-seawater exchange budgets can be evaluated in the light of the geological evolution of the PAB. Based on immobile element ratios of whole rocks and REE characteristics of relict clinopyroxene in the only incompletely altered sample, an E-type MORB primary composition of the basalts can be reconstructed. Our data suggest that the degrees of mantle melting were much higher than during extrusion of the <4 Ma old alkali-basalts recovered from the top of PAB (Beier et al., 2015, doi:10.1130/2015.2511(02)), and even higher than modern MORB at the adjacent mid-Atlantic Ridge. These results lead us to suggest that the deeper sections of the PAB formed during the

  20. Can Plant-Based Natural Flax Replace Basalt and E-Glass for Fiber-Reinforced Polymer Tubular Energy Absorbers? A Comparative Study on Quasi-Static Axial Crushing

    Directory of Open Access Journals (Sweden)

    Libo Yan

    2017-12-01

    Full Text Available Using plant-based natural fibers to substitute glass fibers as reinforcement of composite materials is of particular interest due to their economic, technical, and environmental significance. One potential application of plant-based natural fiber reinforced polymer (FRP composites is in automotive engineering as crushable energy absorbers. Current study experimentally investigated and compared the energy absorption efficiency of plant-based natural flax, mineral-based basalt, and glass FRP (GFRP composite tubular energy absorbers subjected to quasi-static axial crushing. The effects of number of flax fabric layer, the use of foam filler and the type of fiber materials on the crashworthiness characteristics, and energy absorption capacities were discussed. In addition, the failure mechanisms of the hollow and foam-filled flax, basalt, and GFRP tubes in quasi-static axial crushing were analyzed and compared. The test results showed that the energy absorption capabilities of both hollow and foam-filled energy absorbers made of flax were superior to the corresponding energy absorbers made of basalt and were close to energy absorbers made of glass. This study, therefore, indicated that flax fiber has the great potential to be suitable replacement of basalt and glass fibers for crushable energy absorber application.

  1. Safety Implications of the Kentucky Schoolbus Crash. Hearing before the Subcommittee on Transportation, Tourism, and Hazardous Materials of the Committee on Energy and Commerce. House of Representatives, One Hundredth Congress, Second Session.

    Science.gov (United States)

    Congress of the U.S., Washington, DC. House Committee on Energy and Commerce.

    This publication is a collection of the statements made in a hearing before the Subcommittee on Transportation, Tourism, and Hazardous Materials of the Committee on Energy and Commerce of the House of Representatives. In particular, the topic was the safety implications of a Kentucky school bus crash on May 14, 1984. Discussed are the issues of…

  2. Tracking the Depleted Mantle Signature in Melt Inclusions and Residual Glass of Basaltic Martian Shergottites using Secondary Ionization Mass Spectrometry

    Science.gov (United States)

    Peters, Timothy J.; Simon, Justin I.; Jones, John H.; Usui, Tomohiro; Economos, Rita C.; Schmitt, Axel K.; McKeegan, Kevin D.

    2013-01-01

    Trace element abundances of depleted shergottite magmas recorded by olivine-hosted melt inclusions (MI) and interstitial mesostasis glass were measured using the Cameca ims-1270 ion microprobe. Two meteorites: Tissint, an olivine-­phyric basaltic shergottite which fell over Morocco July 18th 2001; and the Antarctic meteorite Yamato 980459 (Y98), an olivine-phyric basaltic shergottite with abundant glassy mesostasis have been studied. Chondrite-­normalized REE patterns for MI in Tissint and Y98 are characteristically LREE depleted and, within analytical uncertainty, parallel those of their respective whole rock composition; supporting each meteorite to represent a melt composition that has experienced closed-­system crystallization. REE profiles for mesostasis glass in Y98 lie about an order of magnitude higher than those from the MI; with REE profiles for Tissint MI falling in between. Y98 MI have the highest average Sm/Nd and Y/Ce ratios, reflecting their LREE depletion and further supporting Y98 as one of our best samples to probe the depleted shergotitte mantle. In general, Zr/Nb ratios overlap between Y98 and Tissint MI, Ce/Nb ratios overlap between Y98 MI and mesostasis glass, and Sm/Nd ratios overlap between Y98 mesostasis glass and Tissint MI. These features support similar sources for both, but with subtle geochemical differences that may reflect different melting conditions or fractionation paths during ascent from the mantle. Interestingly, the REE patterns for both Y98 bulk and MI analyses display a flattening of the LREE that suggests a crustal contribution to the Y98 parent melt. This observation has important implications for the origins of depleted and enriched shergottites.

  3. Calcites from Ocean Crust Basalts: Reliable Proxy Archives?

    Science.gov (United States)

    Böhm, Florian; Eisenhauer, Anton

    2017-04-01

    Calcite cements in ocean crust basalts of the deep sea form from mixtures of cold seawater and warm hydrothermal fluids (about 0-70°C). These low temperature alteration (LTA) calcites have recently gained new interest as proxy recorders of seawater composition (Refs. 1-5). Recent LTA calcite reconstructions of the Sr/Ca and Mg/Ca evolution in ocean waters point to considerably lower Sr/Ca and Mg/Ca ratios during the Cretaceous and Paleogene than in the modern ocean. However, diagenetic alteration in contact with the basalt host rock may change the composition of the LTA calcites. For testing the reliability of LTA calcite records of seawater composition multi-proxy approaches are applied: oxygen isotopes indicate precipitation temperatures, strontium isotopes (87Sr/86Sr) and trace elements indicate influences from hydrothermal fluids. Additional information about the influence of basement rocks on LTA calcite composition can be derived from analyses of stable calcium and strontium isotopes (44/40Ca, 88/86Sr). We find low 44/40Ca values for DSDP and ODP sites where the 87Sr/86Sr ratios of LTA calcites indicate basement influence. On the other hand, for some sites the 87Sr/86Sr values inidicate precipitation from pristine seawater, while low 44/40Ca values indicate basement influence. All of these sites are either older than 50 Myr or show calcite precipitation temperatures >50°C. Sites that are younger than 25 Myr and had formation temperatures 50°C significantly higher 88/86Sr values were observed. The calcium isotope results indicate basement influence on LTA calcite composition at temperatures >10°C. Radiogenic strontium isotopes, in contrast, can be used as unequivocal basement influence indicators only at temperatures above 30°C. Below about 20°C 87Sr/86Sr ratios are no reliable indicators of basement influence. All LTA calcites of sites older than 50 Myr formed (or recrystallized) at temperatures >15°C. Low 44/40Ca values indicate that

  4. Hematite Spherules in Basaltic Tephra Altered Under Aqueous, Acid-Sulfate Conditions on Mauna Kea Volcano, Hawaii: Possible Clues for the Occurrence of Hematite-Rich Spherules in the Burns Formation at Meridiani Planum, Mars

    Science.gov (United States)

    Morris, R. V.; Ming, D. W.; Graff, T. G.; Arvidson, R. E.; Bell, J. F., III; Squyres, S. W.; Mertzman, S. A.; Gruener, J. E.; Golden, D. C.; Robinson, G. A.

    2005-01-01

    Iron-rich spherules (>90% Fe2O3 from electron microprobe analyses) approx.10-100 microns in diameter are found within sulfate-rich rocks formed by aqueous, acid-sulfate alteration of basaltic tephra on Mauna Kea volcano, Hawaii. Although some spherules are nearly pure Fe, most have two concentric compositional zones, with the core having a higher Fe/Al ratio than the rim. Oxide totals less than 100% (93-99%) suggest structural H2O and/or /OH. The transmission Moessbauer spectrum of a spherule-rich separate is dominated by a hematite (alpha-Fe2O3) sextet whose peaks are skewed toward zero velocity. Skewing is consistent with Al(3+) for Fe(3+) substitution and structural H2O and/or /OH. The grey color of the spherules implies specular hematite. Whole-rock powder X-ray diffraction spectra are dominated by peaks from smectite and the hydroxy sulfate mineral natroalunite as alteration products and plagioclase feldspar that was present in the precursor basaltic tephra. Whether spherule formation proceeded directly from basaltic material in one event (dissolution of basaltic material and precipitation of hematite spherules) or whether spherule formation required more than one event (formation of Fe-bearing sulfate rock and subsequent hydrolysis to hematite) is not currently constrained. By analogy, a formation pathway for the hematite spherules in sulfate-rich outcrops at Meridiani Planum on Mars (the Burns formation) is aqueous alteration of basaltic precursor material under acid-sulfate conditions. Although hydrothermal conditions are present on Mauna Kea, such conditions may not be required for spherule formation on Mars if the time interval for hydrolysis at lower temperatures is sufficiently long.

  5. Structural Behavior of Concrete Beams Reinforced with Basalt Fiber Reinforced Polymer (BFRP) Bars

    Science.gov (United States)

    Ovitigala, Thilan

    The main challenge for civil engineers is to provide sustainable, environmentally friendly and financially feasible structures to the society. Finding new materials such as fiber reinforced polymer (FRP) material that can fulfill the above requirements is a must. FRP material was expensive and it was limited to niche markets such as space shuttles and air industry in the 1960s. Over the time, it became cheaper and spread to other industries such as sporting goods in the 1980-1990, and then towards the infrastructure industry. Design and construction guidelines are available for carbon fiber reinforced polymer (CFRP), aramid fiber reinforced polymer (AFRP) and glass fiber reinforced polymer (GFRP) and they are currently used in structural applications. Since FRP is linear elastic brittle material, design guidelines for the steel reinforcement are not valid for FRP materials. Corrosion of steel reinforcement affects the durability of the concrete structures. FRP reinforcement is identified as an alternative to steel reinforcement in corrosive environments. Although basalt fiber reinforced polymer (BFRP) has many advantages over other FRP materials, but limited studies have been done. These studies didn't include larger BFRP bar diameters that are mostly used in practice. Therefore, larger beam sizes with larger BFRP reinforcement bar diameters are needed to investigate the flexural and shear behavior of BFRP reinforced concrete beams. Also, shear behavior of BFRP reinforced concrete beams was not yet studied. Experimental testing of mechanical properties and bond strength of BFRP bars and flexural and shear behavior of BFRP reinforced concrete beams are needed to include BFRP reinforcement bars in the design codes. This study mainly focuses on the use of BFRP bars as internal reinforcement. The test results of the mechanical properties of BFRP reinforcement bars, the bond strength of BFRP reinforcement bars, and the flexural and shear behavior of concrete beams

  6. Like a cannonball: origin of dense spherical basaltic ejecta

    Science.gov (United States)

    Di Piazza, Andrea; Del Bello, Elisabetta; Mollo, Silvio; Vona, Alessandro; Alvarado, Guillermo E.; Masotta, Matteo

    2017-05-01

    Cannonballs are rare spherical to sub-spherical eruptive products associated with basaltic explosive activity. The origin of cannonballs is still debated and subjected to a wide spectrum of different interpretations. In order to better understand the physicochemical mechanisms controlling the formation of these explosive products, we investigated the textural and chemical features of cannonballs from the Cerro Chopo monogenetic volcano (Costa Rica). These explosive products ubiquitously show a core domain with coalesced bubbles (30-36% porosity) wrapped in a dense rim domain with small, isolated bubbles (20-27% porosity). Both domains are identical in terms of bulk rock composition and mineral chemistry and are portions of the same magma batch. Results from combined petrological and thermodynamic modeling indicate that a low-viscosity ( 20 Pa s) melt containing early-formed olivine phenocrysts ( 9 vol.%) ascended from storage at a decompression rate of 0.5 MPa s-1 until it reached a depth of 4.5 km (equivalent to a pressure of 150 MPa). While rising from depth to 4.5 km, the melt underwent rapid decompression (0.5-2.6 MPa s-1) and H2O exsolution, driving late-stage crystallization of the groundmass. The fast ascent velocity (21-110 m s-1) while rising between 4.5 km and the surface induced turbulent (Re >103), annular flow development in the uppermost region of the conduit. We propose that cannonballs represent blebs of fluid magmas that underwent shear-driven detachment from the annulus of magma lining the conduit walls at depths lower than 4.5 km. The formation of such cannonballs is dictated by magma transport dynamics of low-viscosity, phenocryst-poor, and volatile-rich melts that rapidly accelerate within the shallow conduit.

  7. Kinetics of iron redox reaction in silicate melts: A high temperature Xanes study on an alkali basalt

    Energy Technology Data Exchange (ETDEWEB)

    Cochain, B; Neuville, D R; Roux, J; Strukelj, E; Richet, P [Physique des Mineraux et Magmas, Geochimie-Cosmochimie, CNRS-IPGP, 4 place Jussieu, 75005 Paris (France); Ligny, D de [Universite Claude Bernard Lyon 1, LPCML, F-69622 Villeurbanne (France); Baudelet, F, E-mail: cochain@ipgp.jussieu.f [Synchrotron SOLEIL, L' Orme des Merisiers, Saint Aubin (France)

    2009-11-15

    In Earth and Materials sciences, iron is the most important transition element. Glass and melt properties are strongly affected by iron content and redox state with the consequence that some properties (i.e. viscosity, heat capacity, crystallization...) depend not only on the amounts of Fe{sup 2+} and Fe{sup 3+}, but also on the coordination state of these ions. In this work we investigate iron redox reactions through XANES experiments at the K-edge of iron. Using a high-temperature heating device, pre-edge of XANES spectra exhibits definite advantages to make in-situ measurements and to determine the evolution of redox state with time, temperature and composition of synthetic silicate melts. In this study, new kinetics measurements are presented for a basalt melt from the 31,000-BC eruption of the Puy de Lemptegy Volcano in France. These measurements have been made between 773 K and at superliquidus temperatures up to 1923 K.

  8. Summary of INEL research on the iron-enriched basalt waste form

    International Nuclear Information System (INIS)

    Reimann, G.A.; Grandy, J.D.; Eddy, T.L.; Anderson, G.L.

    1992-01-01

    This report summarizes the knowledge base on the iron-enriched basalt (IEB) waste form developed at the Idaho National Engineering Laboratory (INEL) during 1979--1982. The results presented discuss the applicability of IEB in converting retrieved transuranic (TRU) waste from INEL's Radioactive Waste Management Complex (RWMC) into a vitreous/ceramic (glassy/rock) stable waste form suitable for permanent disposal in an appropriate repository, such as the Waste Isolation Pilot Plant (WIPP) in New Mexico. Borosilicate glass (BSG), the approved high-level waste form, appears unsuited for this application. Melting the average waste-soil mix from the RWMC produces the IEB composition and attempting to convert IEB to the BSG composition would require additions of substantial B 2 0 3 , Na, and SiO 2 (glass frit). IEB requires processing temperatures of 1400 to 1600 degrees C, depending upon the waste composition. Production of the IEB waste form, using Joule heated melters, has proved difficult in the past because of electrode and refractory corrosion problems associated with the high temperature melts. Higher temperature electric melters (arc and plasma) are available to produce this final waste form. Past research focused on extensive slag property measurements, waste form leachability tests, mechanical, composition, and microstructure evaluations, as well as a host of experiments to improve production of the waste form. Past INEL studies indicated that the IEB glass-ceramic is a material that will accommodate and stabilize a wide range of heterogeneous waste materials, including long lived radionuclides and scrap metals, while maintaining a superior level of chemical and physical performance characteristics. Controlled cooling of the molten IEB and subsequent heat treatment will produce a glass-ceramic waste form with superior leach resistance

  9. Mass-dependent Mo isotope variations in oceanic basalts - a new tracer for mantle recycling processes

    Science.gov (United States)

    Willbold, M.; Freymuth, H.; Hibbert, K.; Lai, Y. J.; Elliott, T.

    2016-12-01

    How and to what extent crustal material is recycled into the deeper mantle as a result of plate tectonic processes is a long-standing but still not fully understood question in Earth Sciences. Indirect evidence from chemical as well as radiogenic isotope data in oceanic basalts suggest that such a process may indeed have operated over much of Earth's history. Yet, uncertainties in characterising the age of the presumed recycled crustal components as well as the wide range in their chemical composition do not allow us to verify the mantle recycling hypothesis. Technological advances now enable us to explore new isotopic tracers that could shed light on this question. One of these new tools are mass-dependent isotope variation of molybdenum (Mo). Mass-dependent Mo isotope data in clastic and chemical sediments are a well-established geochemical tool to study redox conditions in the Earth's water masses over the geological past [1, 2, 3]. Being an intrinsic property of rocks exposed to the hydrosphere (see Anbar [4] for an overview), mass-dependent Mo isotope variation in mantle-derived rocks from oceanic settings could therefore be used a tracer of recycled crustal material in the Earth's mantle. In this contribution we provide a current overview over how different geological and magmatic processes - such as seawater alteration of oceanic crust, slab dehydration during plate subduction as well as magmatic emplacement - could affect the Mo isotopic composition of crustal components being transferred into the deeper mantle, as well as that of mantle melts that may contain such a recycled component. With this in mind, we explore the use of mass-dependent Mo isotope variations in mantle-derived rocks as a tracer of recycled crust in the mantle. [1] Archer & Vance (2008) Nature Geoscience 1, 597-600. [2] Barling et al. (2001) EPSL 193, 447-457. [3] Siebert et al. (2003) EPSL 211, 159-171. [4] Anbar (2004) Rev. Min. Geochem. 55, 429-454.

  10. Role for syn-eruptive plagioclase disequilibrium crystallisation in basaltic magma ascent dynamics

    Science.gov (United States)

    La Spina, Giuseppe; Burton, Mike; de'Michieli Vitturi, Mattia; Arzilli, Fabio

    2017-04-01

    Magma ascent dynamics in volcanic conduits play a key role in determining the eruptive style of a volcano. The lack of direct observations inside the conduit means that numerical conduit models, constrained with observational data, provide invaluable tools for quantitative insights into complex magma ascent dynamics. The highly nonlinear, interdependent processes involved in magma ascent dynamics require several simplifications when modelling their ascent. For example, timescales of magma ascent in conduit models are typically assumed to be much longer than crystallisation and gas exsolution for basaltic eruptions. However, it is now recognized that basaltic magmas may rise fast enough for disequilibrium processes to play a key role on the ascent dynamics. The quantification of the characteristic times for crystallisation and exsolution processes are fundamental to our understanding of such disequilibria and ascent dynamics. Using observations from Mount Etna's 2001 eruption and a magma ascent model we are able to constrain timescales for crystallisation and exsolution processes. Our results show that plagioclase reaches equilibrium in 1-2 h, whereas ascent times were 1 h. Furthermore, we have related the amount of plagioclase in erupted products with the ascent dynamics of basaltic eruptions. We find that relatively high plagioclase content requires crystallisation in a shallow reservoir, whilst a low plagioclase content reflects a disequilibrium crystallisation occurring during a fast ascent from depth to the surface. Using these new constraints on disequilibrium plagioclase crystallisation we also reproduce observed crystal abundances for different basaltic eruptions: Etna 2002/2003, Stromboli 2007 (effusive eruption) and 1930 (paroxysm) and different Pu'u' O'o eruptions at Kilauea (episodes 49-53). Therefore, our results show that disequilibrium processes play a key role on the ascent dynamics of basaltic magmas and cannot be neglected when describing basaltic

  11. The boron and lithium isotopic composition of mid-ocean ridge basalts and the mantle

    Science.gov (United States)

    Marschall, Horst R.; Wanless, V. Dorsey; Shimizu, Nobumichi; Pogge von Strandmann, Philip A. E.; Elliott, Tim; Monteleone, Brian D.

    2017-06-01

    A global selection of 56 mid-ocean ridge basalt (MORB) glasses were analysed for Li and B abundances and isotopic compositions. Analytical accuracy and precision of analyses constitute an improvement over previously published MORB data and allow a more detailed discussion of the Li and B systematics of the crust-mantle system. Refined estimates for primitive mantle abundances ([ Li ] = 1.39 ± 0.10 μg/g and [ B ] = 0.19 ± 0.02 μg/g) and depleted mantle abundances ([ Li ] = 1.20 ± 0.10 μg/g and [ B ] = 0.077 ± 0.010 μg/g) are presented based on mass balance and on partial melting models that utilise observed element ratios in MORB. Assimilation of seawater (or brine) or seawater-altered material beneath the ridge, identified by high Cl / K , causes significant elevation of MORB δ11 B and variable elevation in δ7 Li . The B isotope ratio is, hence, identified as a reliable indicator of assimilation in MORB and values higher than -6‰ are strongly indicative of shallow contamination of the magma. The global set of samples investigated here were produced at various degrees of partial melting and include depleted and enriched MORB from slow and fast-spreading ridge segments with a range of radiogenic isotope signatures and trace element compositions. Uncontaminated (low- Cl / K) MORB show no significant boron isotope variation at the current level of analytical precision, and hence a homogenous B isotopic composition of δ11 B = - 7.1 ± 0.9 ‰ (mean of six ridge segments; 2SD). Boron isotope fractionation during mantle melting and basalt fractionation likely is small, and this δ11 B value reflects the B isotopic composition of the depleted mantle and the bulk silicate Earth, probably within ±0.4‰. Our sample set shows a mean δ7 Li = + 3.5 ± 1.0 ‰ (mean of five ridge segments; 2SD), excluding high- Cl / K samples. A significant variation of 1.0-1.5‰ exists among various ridge segments and among samples within individual ridge segments, but this

  12. Assessing the efficacy of dredged materials from Lake Panasoffkee, Florida: implication to environment and agriculture. Part 1: Soil and environmental quality aspect.

    Science.gov (United States)

    Sigua, Gilbert C; Holtkamp, Mike L; Coleman, Samuel W

    2004-01-01

    Dredged materials because of its variable but unique physical and chemical properties are often viewed by society and regulators as pollutants, but many have used these materials in coastal nourishment, land or wetland creation, construction materials, and for soil improvement as a soil amendment. Environmental impact assessment is an important pre-requisite to many dredging initiatives. The ability to reuse lake-dredge materials (LDM) for agricultural purposes is important because it reduces the need for off-shore disposal and provides an alternative to disposal of the materials in landfills. Additional research on disposal options of dredged materials are much needed to supply information on criteria testing and evaluation of the physical and chemical impacts of dredged materials at a disposal site, as well as information on many other aspects of dredging and dredged material disposal. While preliminary efforts are underway to provide information to establish criteria for land disposal, testing procedures for possible land disposal of contaminated sediments are still in their developing stage. The objective of this study (Part 1) was to quantify the effect of applied LDM from Lake Panasoffkee (LP), Florida on soil physico-chemical properties (soil quality) at the disposal site. This series of two papers aims at providing assessment of the efficacy of lake-dredged materials from LP especially its implication to environment (soil quality, Part 1) and agriculture (forage quality and pasture establishment, Part 2). The experimental treatments that were evaluated consisted of different ratios of natural soil (NS) to LDM: LDM0 (100% NS:0% LDM); LDM25 (75% NS:25% LDM); LDM50 (50% NS:50% LDM); LDM75 (25% NS:75% LDM); and LDM100 (0% NS:100% LDM). Field layout was based on the principle of a completely randomized block design with four replications. The Mehlich 1 method (0.05 N HCl in 0.025 N H2SO4) was used for chemical extraction of soil. Soil P and other exchangeable

  13. Assessing the efficacy of dredged materials from Lake Panasoffkee, Florida: implication to environment and agriculture. Part 2: pasture establishment and forage productivity.

    Science.gov (United States)

    Sigua, Gilbert C; Holtkamp, Mike L; Coleman, Samuel W

    2004-01-01

    Current dredged material disposal alternatives have several limitations. Options for dealing with dredged materials include leaving them alone, capping them with clean sediments, placing them in confined facilities, disposing of them at upland sites, treating them chemically, or using them for wetlands creation or other beneficial uses The ability to reuse lake-dredge materials (LDM) for agricultural purposes is important because it reduces the need for offshore disposal and provides an alternative to disposal of the materials in landfills. Often these materials can be obtained at little or no cost to the farmers or landowners. Thus, forage production offers an alternative to waste management since nutrients in the LDM are recycled into crops that are not directly consumed by humans. The objective of this study (Part 2) were to: (1) assess dredge materials from Lake Panasoffkee, Florida as a soil amendment to establish bahiagrass (BG) in a subtropical beef cattle pasture in Sumter County, Florida; and (2) determine the effect of LDM application on the crude protein (CP) and nutrient uptake of BG. This series of two papers aims at providing assessment of the efficacy of lake-dredged materials especially its implication to environment (soil quality, Part 1) and agriculture (forage quality and pasture establishment, Part 2). The experimental treatments that were evaluated consisted of different ratios of natural soil (NS) to LDM: LDM0 (100% NS:0% LDM); LDM25 (75% NS:25% LDM); LDM50 (50% NS:50% LDM); LDM75 (25% NS:75% LDM); and LDM100 (0% NS:100% LDM). Bahiagrass plots at its early establishment were cut to a 5-cm stubble height on Julian days 112 and harvested to the same stubble height on Julian days 238 and on Julian days 546 following the double-ring method. Field layout was based on the principle of a completely randomized block design with four replications. Plant samples harvested at 546 Julian days were ground to pass through a 1-mm mesh screen in a Wiley mill

  14. Geochemical insights into the lithology of mantle sources for Cenozoic alkali basalts in West Qinling, China

    Science.gov (United States)

    Dai, Li-Qun; Zheng, Fei; Zhao, Zi-Fu; Zheng, Yong-Fei

    2018-03-01

    Although alkali basalts are common in oceanic islands and continental rifts, the lithology of their mantle sources is still controversial. While the peridotite is usually viewed as a common source lithology, there are increasing studies suggesting significant contributions from ultramafic metasomatites such as carbonated peridotite, pyroxenite and hornblendite to the origin of alkali basalts. The present study indicates that carbonated peridotite plus hornblendite would have served as the mantle sources of Cenozoic alkali basalts from the West Qinling orogen in China. The target basalts show low SiO2 contents of 36.9 to 40.8 wt% and highly variable Na2O + K2O contents from 0.86 to 4.77 wt%, but high CaO contents of 12.5 to 16.3 wt% and CaO/Al2O3 ratios of 1.42 to 2.19. They are highly enriched in the majority of incompatible trace elements, but depleted in Rb, K, Pb, Zr, Hf, and Ti. Furthermore, they exhibit high (La/Yb)N, Zr/Hf, Ce/Pb and Nb/Ta ratios, but low Ti/Eu and Hf/Sm ratios. Generally, with increasing (La/Yb)N and CaO/Al2O3 ratios, their Ti/Eu and Hf/Sm ratios decrease whereas their Zr/Hf, Ce/Pb and Nb/Ta ratios increase. These major and trace element features are similar to those of carbonatites and hornblendite-derived melts to some extent, but significantly different from those of mid-ocean ridge basalts (MORB). This suggests that the alkali basalts would be originated from metasomatic mantle sources. A comparison of the major-trace elements in the alkali basalts with those of some representative mantle-derived melts indicates that the source lithology of alkali basalts is a kind of ultramafic metasomatites that are composed of carbonated peridotite and hornblendite. Such metasomatites would be generated by reaction of the depleted MORB mantle peridotite with hydrous, carbonate-bearing felsic melts derived from partial melting of the subducted Paleotethyan oceanic crust. Therefore, the melt-peridotite reaction at the slab-mantle interface in the

  15. Technical support for GEIS: radioactive waste isolation in geologic formations. Volume 7. Baseline rock properties-basalt

    Energy Technology Data Exchange (ETDEWEB)

    1978-04-01

    This volume, Y/OWI/TM-36/7 Baseline Rock Properties--Basalt, is one of a 23-volume series, ''Technical Support for GEIS: Radioactive Waste Isolation in Geologic Formations, Y/OWI/TM-36'' which supplements a ''Contribution to Draft Generic Environmental Impact Statement on Commercial Waste Management: Radioactive Waste Isolation in Geologic Formations, Y/OWI/TM-44.'' The series provides a more complete technical basis for the preconceptual designs, resource requirements, and environmental source terms associated with isolating commercial LWR wastes in underground repositories in salt, granite, shale and basalt. Wastes are considered from three fuel cycles: uranium and plutonium recycling, no recycling of spent fuel and uranium-only recycling. This report contains an evaluation of the results of a literature survey to define the rock mass properties of a generic basalt, which could be considered as a geological medium for storing radioactive waste. The general formation and structure of basaltic rocks is described. This is followed by specific descriptions and rock property data for the Dresser Basalt, the Amchitka Island Basalt, the Nevada Test Site Basalt and the Columbia River Group Basalt. Engineering judgment has been used to derive the rock mass properties of a typical basalt from the relevant intact rock property data and the geological information pertaining to structural defects, such as joints and faults.

  16. A chemical model for generating the sources of mare basalts - Combined equilibrium and fractional crystallization of the lunar magmasphere

    Science.gov (United States)

    Snyder, Gregory A.; Taylor, Lawrence A.; Neal, Clive R.

    1992-01-01

    A chemical model for simulating the sources of the lunar mare basalts was developed by considering a modified mafic cumulate source formed during the combined equilibrium and fractional crystallization of a lunar magma ocean (LMO). The parameters which influence the initial LMO and its subsequent crystallization are examined, and both trace and major elements are modeled. It is shown that major elements tightly constrain the composition of mare basalt sources and the pathways to their creation. The ability of this LMO model to generate viable mare basalt source regions was tested through a case study involving the high-Ti basalts.

  17. Hydrogeological and quantitative groundwater assessment of the Basaltic Aquifer, Northern Harrat Rahat, Saudi Arabia

    International Nuclear Information System (INIS)

    Al-Shaibani, A.; Abokhodair, Abdulwahab A.; Lloyd, J.W.; Al-Ahmari, A.

    2007-01-01

    The Northern Harrat Rahat consists of 300m basalt lavas covering some 2000 km2 to the south-east of Al-Madinah in western Saudi Arabia. Like many basalt sequences, the Rahat basalts form an important aquifer and groundwater resource. The aquifer has a saturated thickness of up to 60m and made up of the weathered upper part of underlying basement, pre-basalt sands and gravels and the fractured basalts. Since 1992, groundwater has been abstracted from the aquifer as part of the Al-Madinah water supply. To assess the potential of the aquifer an assessment has been made based on pumping tests of 70 wells. The hydraulic parameters have been shown to be highly variable typical of the fractured domain. The aquifer contains good-quality water in storage, but receives limited recharge. Groundwater temperature anomalies indicate remnant volcanic activity locally. A numerical groundwater model has been constructed, which has been calibrated using limited groundwater head measurements, but with good abstraction records. Prediction of groundwater heads and the examination of several abstraction scenarios indicate that the aquifer can continue to support part of the Al-Madinah demand for the next several years, if certain well distributions are adopted. The predictions also show that the aquifer can only support the total demand of the city for a few days as a contingency resource. (author)

  18. Generation of Northern Parana High Ti/Y Basalts By Progressive Lithospheric Thinning Above a "Gough"-like Mantle Source.

    Science.gov (United States)

    Peate, D. W.

    2015-12-01

    Stratigraphic and geochronologic data show that the high Ti/Y magma types (Pitanga & Paranapanema) of NW Paraná are the youngest magmatic phase in the Paraná-Etendeka flood basalt province and comprise ~50% of the total erupted volume. They are more homogeneous than low Ti/Y basalts in SE Paraná and the Etendeka, with a restricted range in Sr-Nd-Pb isotope composition (87Sr/86Sr 0.7055-0.7063; ɛNd -5 to -3; 206Pb/204Pb 17.7-18.2). Subtle differences between Pitanga and Paranapanema (Th/Ta, 206Pb/204Pb) are consistent with minor crustal assimilation. Pitanga show greater incompatible element enrichment compared to Paranapanema (Ti/Y 440-590 vs. 325-510; La/Yb 9.3-12.2 vs. 5.9-9.0), and have greater MREE/HREE enrichment (Dy/Yb 2.1-2.5 vs. 1.8-2.1). Boreholes and surface profiles reveal a consistent temporal transition from Pitanga to Paranapanema lavas, and the decrease in Dy/Yb requires a shallowing of the mean depth of melting, consistent with lithospheric thinning. Pitanga and Paranapanema lavas show Dupal characteristics (elevated Δ7/4Pb 8-13), distinct from Tristan hot-spot and S Atlantic MORB compositions, but similar to the EM-I endmember composition from Walvis Ridge DSDP Site 525A. Previous workers suggested a common origin for Parana high Ti/Y magmas and DSDP Site 525A in continental lithospheric mantle. However, recent comprehensive sampling of the Tristan - Gough - Walvis Ridge - Rio Grande Rise hotspot track has revealed spatial geochemical zonation with a northern "Tristan"-track and a southern "Gough"-track, and the "Tristan" component (Δ7/4Pb 3-6) is only found in samples < 70 Ma (Hoernle et al. 2015). The early hotspot track history is dominated by the "Gough" component (Δ7/4Pb 6-13), inferred to be derived from the African LLSVP, and this material has the compositional features (Sr-Nd-Pb-Hf isotopes, elevated La/Nb and Th/Nb) required for the mantle source for the Pitanga and Paranapanema magma types of the 135 Ma Paraná flood basalt

  19. Seed dormancy mechanisms in basalt milkvetch and western prairie clover

    Science.gov (United States)

    A greater diversity of native legumes and forbs is desirable for rangeland restoration practice in the Intermountain Region of the western U.S. However, for such diversity to materialize in the seed marketplace and to be effective in restoration practice, plant materials are needed that can be germ...

  20. Episodic soil succession on basaltic lava fields in a cool, dry environment

    Science.gov (United States)

    Vaughan, K.L.; McDaniel, P.A.; Phillips, W.M.

    2011-01-01

    Holocene- to late Pleistocene-aged lava flows at Craters of the Moon National Monument and Preserve provide an ideal setting to examine the early stages of soil formation under cool, dry conditions. Transects were used to characterize the amount and nature of soil cover on across basaltic lava flows ranging in age from 2.1 to 18.4 ka. Results indicate that on flows soils (Folists in Soil Taxonomy) are the dominant soil type, providing an areal coverage of up to ∼25%. On flows ≥13.9 ka, deeper mineral soils including Entisols, Aridisols, and Mollisols become dominant and the areal extent increases to ≥95% on flows older than 18.4 ka. These data suggest there are two distinct pedogenic pathways associated with lava flows of the region. The first pathway is illustrated by the younger flows, where Folists dominate. In the absence of a major source of loess, relatively little mineral material accumulates and soils provide only minor coverage of the lava flows. Our results indicate that this pathway of soil development has not changed appreciably over the past ∼10 ka. The second pedogenic pathway is illustrated by the flows older than 13.9 ka. These flows have been subject to deposition of large quantities of loess during and after the last regional glaciation, resulting in almost complete coverage. Subsequent pedogenesis has given rise to Aridisols and Mollisols with calcic and cambic horizons and mollic epipedons. This research highlights the importance of regional climate change on the evolution of Craters of the Moon soilscapes.

  1. Studies of Basalt Through Laser Induced Breakdown Spectroscopy (LIBS for the Manufacturing of Lapilli Blocks

    Directory of Open Access Journals (Sweden)

    Ismael De la Viuda-Pérez

    2016-10-01

    Full Text Available Basaltic samples selected from different areas of Tenerife were analyzed by applying laser induced breakdown spectroscopy (LIBS, Raman spectroscopy and X Ray Diffraction (XRD in order to identify the basic chemical composition and mineralogy. The basic composition obtained from the analysis was: O, F, Na, K, Mg, Al Si, Ca, Ti and Fe. Raman spectroscopic and XRD analyses indicated a basaltic mineralogy which is consistent with the basic composition results obtained from LIBS. The results of the analyses carried out using portable instrumentation proved the suitability of the LIBS, specially combined with the Raman spectroscopy for their application in the mineralogical-chemical identification in the areas where basalts and lapilli are extracted for construction works in Tenerife.

  2. Bibliography of geologic studies: Columbia Plateau (Columbia River Basalt) and adjacent areas in Idaho

    International Nuclear Information System (INIS)

    Strowd, W.

    1978-11-01

    The objective of this compilation is to present a comprehensive listing of published, unpublished, and open-file references pertaining to the geology of the Columbia Plateau and adjacent areas in the State of Idaho. The bibliography was compiled in support of Rockwell's Basalt Waste Isolation Program that is evaluating the feasibility of nuclear waste storage in the Columbia River Basalt Group. The emphasis is on stratigraphy, structural geology, seismicity, and tectonics, although the nature of Columbia River Basalt distribution in Idaho has necessitated the inclusion of a sizeable collection of references on geology marginal to the Columbia Plateau and associated mineral resources. The bibliography is divided into two major sections, the alphabetical listing of all references and the subject index. The subject index is divided into 19 categories to facilitate locating a specific reference in the user's field of interest

  3. Modeling of the Sedimentary Interbedded Basalt Stratigraphy for the Idaho National Laboratory Probabilistic Seismic Hazard Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Suzette Payne

    2006-04-01

    This report summarizes how the effects of the sedimentary interbedded basalt stratigraphy were modeled in the probabilistic seismic hazard analysis (PSHA) of the Idaho National Laboratory (INL). Drill holes indicate the bedrock beneath INL facilities is composed of about 1.1 km of alternating layers of basalt rock and loosely consolidated sediments. Alternating layers of hard rock and “soft” loose sediments tend to attenuate seismic energy greater than uniform rock due to scattering and damping. The INL PSHA incorporated the effects of the sedimentary interbedded basalt stratigraphy by developing site-specific shear (S) wave velocity profiles. The profiles were used in the PSHA to model the near-surface site response by developing site-specific stochastic attenuation relationships.

  4. Modeling of the Sedimentary Interbedded Basalt Stratigraphy for the Idaho National Laboratory Probabilistic Seismic Hazard Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Suzette Payne

    2007-08-01

    This report summarizes how the effects of the sedimentary interbedded basalt stratigraphy were modeled in the probabilistic seismic hazard analysis (PSHA) of the Idaho National Laboratory (INL). Drill holes indicate the bedrock beneath INL facilities is composed of about 1.1 km of alternating layers of basalt rock and loosely consolidated sediments. Alternating layers of hard rock and “soft” loose sediments tend to attenuate seismic energy greater than uniform rock due to scattering and damping. The INL PSHA incorporated the effects of the sedimentary interbedded basalt stratigraphy by developing site-specific shear (S) wave velocity profiles. The profiles were used in the PSHA to model the near-surface site response by developing site-specific stochastic attenuation relationships.

  5. Hydrochemistry and hydrogeologic conditions within the Hanford Site upper basalt confined aquifer system

    Energy Technology Data Exchange (ETDEWEB)

    Spane, F.A. Jr.; Webber, W.D.

    1995-09-01

    As part of the Hanford Site Ground-Water Surveillance Project, Flow System Characterization Task. Pacific Northwest Laboratory examines the potential for offsite migration of contamination within the upper basalt confined aquifer system for the US Department of Energy (DOE). As part of this activity, groundwater samples were collected over the past 2 years from selected wells completed in the upper Saddle Mountains Basalt. The hydrochemical and isotopic information obtained from these groundwater samples provides hydrologic information concerning the aquifer-flow system. Ideally, when combined with other hydrologic property information, hydrochemical and isotopic data can be used to evaluate the origin and source of groundwater, areal groundwater-flow patterns, residence and groundwater travel time, rock/groundwater reactions, and aquifer intercommunication for the upper basalt confined aquifer system. This report presents the first comprehensive Hanford Site-wide summary of hydrochemical properties for the upper basalt confined aquifer system. This report provides the hydrogeologic characteristics (Section 2.0) and hydrochemical properties (Section 3.0) for groundwater within this system. A detailed description of the range of the identified hydrochemical parameter subgroups for groundwater in the upper basalt confined aquifer system is also presented in Section 3.0. Evidence that is indicative of aquifer contamination/aquifer intercommunication and an assessment of the potential for offsite migration of contaminants in groundwater within the upper basalt aquifer is provided in Section 4.0. The references cited throughout the report are given in Section 5.0. Tables that summarize groundwater sample analysis results for individual test interval/well sites are included in the Appendix.

  6. Geochemical Characterization Of Cherts From The 3.46Ga Apex Basalt To Assess The Origins Of Possible Biosignatures

    Science.gov (United States)

    Bower, D. M.; Steele, A.; Ackerson, M. R.; Bullock, E. S.; Green, O. R.; Fries, M.; Conrad, P. G.

    2017-12-01

    Many terrestrial cherts contain compelling microtextures and mineral phases that are indicative of ancient life in hydrothermal systems on early Earth. In volcanically-derived hydrothermal deposits, cherts have undergone multiple alteration events often resulting in separate generations of quartz veins that are much younger than the host rocks. In some cases, multiple episodes of hydrothermal alteration obscure otherwise syngenetic biosignatures and likewise create false signatures in the form of secondary carbon emplacement or diagenetic phase changes. To better identify possible biosignatures in hydrothermal deposits and understand their origins, we used confocal micro Raman spectroscopy, electron probe microanalysis, and cathodoluminescence (CL) imaging to characterize the quartz fabrics, mineral phases, trace elements, and macromolecular carbon (MMC) in quartz veins from the 3.46 Ga Apex Basalt chert samples. MMC, anatase (TiO2), pyrite (Fe2S), jarosite-alunite (KFe3(SO4)2(OH)6 - Kal3(SO4)2(OH)6), chamosite-phyllosilicates, and Fe-oxides all occur in close association in multiple generations of quartz veins throughout the sample suite. Mineral phases xenotime (YPO4), scorodite (FeAsO4 . H2O), apatite (CaPO4), pentlandite ((Fe,Ni)9S8), barite (BaSO4), sphalerite ((Zn,Fe)S), dolomite ((CaMg(CO3)2) and halides occur in specific generations of quartz. Trace elements (Cr, Mn, Mo, Cu, Sc, Va, Sb, and Co) are heterogeneously distributed within individual samples and likely occur due to fluid scavenging of the host basalts. CL imaging of quartz demonstrates that the majority of silicate material in the Apex cherts underwent recrystallization. This could result in the alteration of MMC and associated mineral assemblages. The biogencity and true origins of morphological features and chemical signatures in the Apex cherts are hotly debated, yet discovering the causes and nature of these puzzling attributes will be key for determining the usefulness of interrogating

  7. Thermobarometry for spinel lherzolite xenoliths in alkali basalts

    Science.gov (United States)

    Ozawa, Kazuhito; Youbi, Nasrrddine; Boumehdi, Moulay Ahmed; Nagahara, Hiroko

    2016-04-01

    geothermobarometry based on reactions with large and distinct volume changes, is necessary. Specification of mineral domains and their components representing the thermal state of the mantle just before xenolith extraction is one of the major tasks for the establishment of reliable geothermobarometry for spinel lherzolite xenoliths. Systematic variations of such mineralogical information among xenoliths transported by a single volcanic eruption guarantees proper estimation of a mantle geotherm. For the development of such geobarometry, it is important to choose appropriate xenolith locality, where previous studies provide enough information and where many xenolith samples are available for extending a range of derivation depth. Spinel lherzolite xenoliths in alkali basalts from Bou Ibalhatene maars in the Middle Atlas in Morocco are suitable study target. Geochemical, geochronological, petrological, and rheological aspects of the spinel lherzolite xenoliths have been studied (Raffone et al. 2009; El Messbahi et al., 2015; Witting et al., 2010; El Azzouzi et al., 2010), which show that they represent fragments of the lithospheric mantle formed and modified since 1.7Ga before their extraction from Miocene to recent. We have pinpointed portions of minerals in the xenolith samples and their components representing condition just before their entrapment in magmas, on which appropriate geothermobarometers are applied and detected ~0.5GPa pressure difference (1.5-2.0GPa) for ~100°C variation in temperatures (950-1050°C).

  8. Technological characterization of basaltic rocks of Canoas I Hydroelectric Power Plant, Paranapanema river, Sao Paulo - Parana states, Brazil; Caracterizacao tecnologica das rochas basalticas da Usina Hidroeletrica Canoas I, Rio Paranapanema, SP/PR

    Energy Technology Data Exchange (ETDEWEB)

    Marrano, Antonio

    1997-07-01

    Basaltic litotypes from the rock mass foundation of Canoas I Hydroelectric Power Plant were submitted to technological characterization tests, in order to verify their suitability as construction material. Physical and mechanical properties (density, porosity, water absorption, ultrasonic velocity, compressive and splitting tensile strength, among others) were determined, besides petrographic analyses. Weather ability tests were also performed, not only through wetting-drying cycles and by immersion in ethylene glycol but by outdoor exposure as well, using crushed and core drilled specimens. Detailed procedures for the weather ability test using core specimens from rotary drilling are given. It is analyzed the influence of a geological feature (fault zone, about 10 meters thick and 20 degrees dip), that occurs in the rock mass foundation, on the technological properties of these rocks. Basaltic litotypes selected as construction material are then pointed out. (author)

  9. Hydrologic bibliography of the Columbia River basalts in Washington with selected annotations

    International Nuclear Information System (INIS)

    Tanaka, H.; Wildrick, L.; Pearson, B.

    1979-08-01

    The objective of this compilation is to present a comprehensive listing of the published, unpublished, and open file references pertaining to the surface and subsurface hydrology of the Columbia River basalts within the State of Washington and is presented in support of Rockwell's hydrologic data compilation effort for the Basalt Waste Isolation Program. A comprehensive, annotated bibliography of the Pasco Basin (including the Hanford Site) hydrology has been prepared for Rockwell as part of the Pasco Basin hydrology studies. In order to avoid unnecessary duplication, no effort was made to include a complete list of bibliographic references on Hanford in this volume

  10. Influences of chemical aging on the surface morphology and crystallization behavior of basaltic glass fibers

    DEFF Research Database (Denmark)

    Lund, Majbritt Deichgræber; Yue, Yuanzheng

    2008-01-01

    The impact of aging in high humidity and water on the surface morphology and crystallization behavior of basaltic glass fibers has been studied using scanning electron microscopy, transmission electron microscopy, calorimetry and X-ray diffraction. The results show that interaction between...... the fibers and the surrounding media (high humidity or water at 70 C) leads to chemical changes strongly affecting the surface morphology. The crystallization peak temperature of the basaltic glass fibers are increased without changing the onset temperature, this may be caused by a chemical depletion...

  11. Determination of Geochemical Bio-Signatures in Mars-Like Basaltic Environments

    Directory of Open Access Journals (Sweden)

    Karen Olsson-Francis

    2017-09-01

    Full Text Available Bio-signatures play a central role in determining whether life existed on early Mars. Using a terrestrial basalt as a compositional analog for the martian surface, we applied a combination of experimental microbiology and thermochemical modeling techniques to identify potential geochemical bio-signatures for life on early Mars. Laboratory experiments were used to determine the short-term effects of biota on the dissolution of terrestrial basalt, and the formation of secondary alteration minerals. The chemoorganoheterotrophic bacterium, Burkholderia sp. strain B_33, was grown in a minimal growth medium with and without terrestrial basalt as the sole nutrient source. No growth was detected in the absence of the basalt. In the presence of basalt, during exponential growth, the pH decreased rapidly from pH 7.0 to 3.6 and then gradually increased to a steady-state of equilibrium of between 6.8 and 7.1. Microbial growth coincided with an increase in key elements in the growth medium (Si, K, Ca, Mg, and Fe. Experimental results were compared with theoretical thermochemical modeling to predict growth of secondary alteration minerals, which can be used as bio-signatures, over a geological timescale. We thermochemically modeled the dissolution of the basalt (in the absence of biota in very dilute brine at 25°C, 1 bar; the pH was buffered by the mineral dissolution and precipitation reactions. Preliminary results suggested that at the water to rock ratio of 1 × 107, zeolite, hematite, chlorite, kaolinite, and apatite formed abiotically. The biotic weathering processes were modeled by varying the pH conditions within the model to adjust for biologic influence. The results suggested that, for a basaltic system, the microbially-mediated dissolution of basalt would result in “simpler” secondary alteration, consisting of Fe-hydroxide and kaolinite, under conditions where the abiotic system would also form chlorite. The results from this study demonstrate

  12. Strengthening of reinforced concrete beams with basalt-based FRP sheets: An analytical assessment

    International Nuclear Information System (INIS)

    Nerilli, Francesca; Vairo, Giuseppe

    2016-01-01

    In this paper the effectiveness of the flexural strengthening of RC beams through basalt fiber-reinforced sheets is investigated. The non-linear flexural response of RC beams strengthened with FRP composites applied at the traction side is described via an analytical formulation. Validation results and some comparative analyses confirm soundness and consistency of the proposed approach, and highlight the good mechanical performances (in terms of strength and ductility enhancement of the beam) produced by basalt-based reinforcements in comparison with traditional glass or carbon FRPs.

  13. Strengthening of reinforced concrete beams with basalt-based FRP sheets: An analytical assessment

    Energy Technology Data Exchange (ETDEWEB)

    Nerilli, Francesca [Unicusano - Università degli Studi Niccolò Cusano Telematica Roma, 00166 Rome (Italy); Vairo, Giuseppe [Università degli Studi di Roma “Tor Vergata”- (DICII), 00133 Rome (Italy)

    2016-06-08

    In this paper the effectiveness of the flexural strengthening of RC beams through basalt fiber-reinforced sheets is investigated. The non-linear flexural response of RC beams strengthened with FRP composites applied at the traction side is described via an analytical formulation. Validation results and some comparative analyses confirm soundness and consistency of the proposed approach, and highlight the good mechanical performances (in terms of strength and ductility enhancement of the beam) produced by basalt-based reinforcements in comparison with traditional glass or carbon FRPs.

  14. Hydrologic bibliography of the Columbia River basalts in Washington with selected annotations

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, H.; Wildrick, L.; Pearson, B.

    1979-08-01

    The objective of this compilation is to present a comprehensive listing of the published, unpublished, and open file references pertaining to the surface and subsurface hydrology of the Columbia River basalts within the State of Washington and is presented in support of Rockwell's hydrologic data compilation effort for the Basalt Waste Isolation Program. A comprehensive, annotated bibliography of the Pasco Basin (including the Hanford Site) hydrology has been prepared for Rockwell as part of the Pasco Basin hydrology studies. In order to avoid unnecessary duplication, no effort was made to include a complete list of bibliographic references on Hanford in this volume.

  15. Solubility and partitioning of Ne, Ar, Kr, and Xe in minerals and synthetic basaltic melts

    Science.gov (United States)

    Broadhurst, C. L.; Drake, M. J.; Hagee, B. E.; Bernatowicz, T. J.

    1992-01-01

    The solubilities of Ne, Ar, Kr, and Xe gases were measured in natural samples of anorthite, diopside, forsterite, spinel, and synthetic basaltic melts, the samples which represent equilibrium pairs in the Fo-An-Di-SiO2 system. Results show that, in natural minerals, the solubilities of these gases increase with increasing atomic number. In contrast, the solubilities of noble gases in the synthetic basaltic melts decreased with increasing atomic number. The partition coefficients increased with increasing atomic number for all mineral/melt pairs.

  16. Early Cretaceous MORB-type basalt and A-type rhyolite in northern Tibet: Evidence for ridge subduction in the Bangong-Nujiang Tethyan Ocean

    Science.gov (United States)

    Fan, Jian-Jun; Li, Cai; Sun, Zhen-Ming; Xu, Wei; Wang, Ming; Xie, Chao-Ming

    2018-04-01

    New zircon U-Pb ages, major- and trace-element data, and Hf isotopic compositions are presented for bimodal volcanic rocks of the Zhaga Formation (ZF) in the western-middle segment of the Bangong-Nujiang suture zone (BNSZ), northern Tibet. The genesis of these rocks is described, and implications for late-stage evolution of the Bangong-Nujiang Tethyan Ocean (BNTO) are considered. Detailed studies show that the ZF bimodal rocks, which occur as layers within a typical bathyal to abyssal flysch deposit, comprise MORB-type basalt that formed at a mid-ocean ridge, and low-K calc-alkaline A-type rhyolite derived from juvenile crust. The combination of MORB-type basalt, calc-alkaline A-type rhyolite, and bathyal to abyssal flysch deposits in the ZF leads us to propose that they formed as a result of ridge subduction. The A-type ZF rhyolites yield LA-ICP-MS zircon U-Pb ages of 118-112 Ma, indicating formation during the Early Cretaceous. Data from the present study, combined with regional geological data, indicate that the BNTO underwent conversion from ocean opening to ocean closure during the Late Jurassic-Early Cretaceous. The eastern segment of the BNTO closed during this period, while the western and western-middle segments were still at least partially open and active during the Early Cretaceous, accompanied by ridge subduction within the Bangong-Nujiang Tethyan Ocean.

  17. Lithium isotope evidence for subduction-enriched mantle in the source of mid-ocean-ridge basalts.

    Science.gov (United States)

    Elliott, Tim; Thomas, Alex; Jeffcoate, Alistair; Niu, Yaoling

    2006-10-05

    'Recycled' crustal materials, returned from the Earth's surface to the mantle by subduction, have long been invoked to explain compositional heterogeneity in the upper mantle. Yet increasingly, problems have been noted with this model. The debate can be definitively addressed using stable isotope ratios, which should only significantly vary in primitive, mantle-derived materials as a consequence of recycling. Here we present data showing a notable range in lithium isotope ratios in basalts from the East Pacific Rise, which correlate with traditional indices of mantle heterogeneity (for example, 143Nd/144Nd ratios). Such co-variations of stable and radiogenic isotopes in melts from a normal ridge segment provide critical evidence for the importance of recycled material in generating chemical heterogeneity in the upper mantle. Contrary to many models, however, the elevated lithium isotope ratios of the 'enriched' East Pacific Rise lavas imply that subducted ocean crust is not the agent of enrichment. Instead, we suggest that fluid-modified mantle, which is enriched during residency in a subduction zone, is mixed back into the upper mantle to cause compositional variability.

  18. Does the presence of bacteria effect basaltic glass dissolution rates? 1: Dead Pseudomonas reactants

    Science.gov (United States)

    Stockmann, Gabrielle J.; Shirokova, Liudmila S.; Pokrovsky, Oleg S.; Oelkers, Eric H.; Benezeth, Pascale

    2010-05-01

    Basaltic glass and crystalline basalt formations in Iceland have been suggested for industrial CO2 storage due to their porous and permeable properties and high reactivity. Acid CO2-saturated waters in contact with basaltic glass will lead to rapid dissolution of the glass and release of divalent cations, (Ca2+, Mg2+, Fe2+) that can react to form stable carbonates and thereby trap the CO2. However, the basalt formations in Iceland not only contains glass and mineral assemblages, but also host microbiological communities that either by their presence or by active involvement in chemical reactions could affect the amount of basaltic glass being dissolved and CO2 being trapped. Samples of natural bacteria communities from the CO2 storage grounds in Iceland were collected, separated, and purified using agar plate technique and cultured under laboratory conditions in nutrient broth-rich media. Heterotrophic aerobic Gram-negative strain of Pseudomonas reactants was selected for a series of flow-through experiments aimed at evaluation of basaltic glass dissolution rate in the presense of increasing amounts of dead bacteria and their lysis products. The experiments were carried out using mixed-flow reactors at pH 4, 6, 8 and 10 at 25 °C. Each of the four reactors contained 1 gram of basaltic glass of the size fraction 45-125 μm. This glass was dissolved in ~ 0.01 M buffer solutions (acetate, MES, bicarbonate and carbonate+bicarbonate mixture) of the desired pH. All experiments ran 2 months, keeping the flowrate and temperature stable and only changing the concentration of dead bacteria in the inlet solutions (from 0 to 430 mg/L). Experiments were performed in sterile conditions, and bacterial growth was prevented by adding NaN3 to the inlet solutions. Routine culturing of bacteria on the agar plates confirmed the sterility of experiments. Samples of outlet solutions were analyzed for major cations and trace elements by ICP-MS. Results demonstrate a slight decrease in the

  19. Geology and geochemistry of paleosols developed on the Hekpoort Basalt, Pretoria Group, South Africa

    Science.gov (United States)

    Rye, R.; Holland, H. D.

    2000-01-01

    The Hekpoort paleosols comprise a regional paleoweathering horizon developed on 2.224 +/- 0.021 Ga basaltic andesite lavas at the top of the Hekpoort Formation of the Pretoria Group, Transvaal Supergroup, South Africa. In five separate profiles, from outcrops along road cuts near Waterval Onder and the Daspoort Tunnel and in three drill cores from the Bank Break Area (BB3, BB8, and BB14), the top of the paleosol is a sericite-rich zone. The sericite zone grades downward into a chlorite-rich zone. In core BB8 and in the road cut at the Daspoort Tunnel, we sampled the underlying or parent basaltic andesite into which the chlorite zone grades. We did not obtain samples of the parent material at Waterval Onder and in cores BB3 and BB14, but chemical analyses indicate that the chlorite and sericite zones in these profiles derive from underlying lavas similar to the ones we sampled in core BB8 and at the Daspoort Tunnel. The presence of apparent rip-up clasts of the paleosol in the overlying ironstones of the Strubenkop Formation in the cores from Bank Break makes it very unlikely that most of the alteration was a result of interactions with hydrothermal fluids. Desiccation cracks at the top of the paleosol that were filled with sand during the deposition of the overlying sediments at Waterval Onder point to a subaerial weathering origin. Very little, if any, Al, Ti, Zr, V, or Cr moved a discernible distance during weathering of any of the five profiles. The vertical distribution of Fe, Mg, Mn, Ni, and Co indicates that these elements were largely removed from the top of the soil during weathering. The overall abundance of these elements in each of the profiles indicates that a significant fraction of the complement lost from the top subsequently reprecipitated in the lower portion of the soil as constituents of an Fe2(+) -rich smectite. The loss of Fe from the top of the soil during weathering of the Hekpoort paleosols indicates that atmospheric PO2 was less than 8 x 10

  20. Industrial implications of hydrogen

    International Nuclear Information System (INIS)

    Pressouyre, G.M.

    1982-01-01

    Two major industrial implications of hydrogen are examined: problems related to the effect of hydrogen on materials properties (hydrogen embrittlement), and problems related to the use and production of hydrogen as a future energy vector [fr

  1. Derivation of intermediate to silicic magma from the basalt analyzed at the Vega 2 landing site, Venus.

    Science.gov (United States)

    Shellnutt, J Gregory

    2018-01-01

    Geochemical modeling using the basalt composition analyzed at the Vega 2 landing site indicates that intermediate to silicic liquids can be generated