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Sample records for accompanying mineral crystal

  1. 30 CFR 250.246 - What mineral resource conservation information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What mineral resource conservation information must accompany the DPP or DOCD? 250.246 Section 250.246 Mineral Resources MINERALS MANAGEMENT SERVICE... Coordination Documents (docd) § 250.246 What mineral resource conservation information must accompany the...

  2. 30 CFR 550.246 - What mineral resource conservation information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 2 2012-07-01 2012-07-01 false What mineral resource conservation information must accompany the DPP or DOCD? 550.246 Section 550.246 Mineral Resources BUREAU OF OCEAN ENERGY... Operations Coordination Documents (docd) § 550.246 What mineral resource conservation information...

  3. 30 CFR 550.246 - What mineral resource conservation information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 2 2013-07-01 2013-07-01 false What mineral resource conservation information must accompany the DPP or DOCD? 550.246 Section 550.246 Mineral Resources BUREAU OF OCEAN ENERGY... Operations Coordination Documents (docd) § 550.246 What mineral resource conservation information...

  4. 30 CFR 550.246 - What mineral resource conservation information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 2 2014-07-01 2014-07-01 false What mineral resource conservation information must accompany the DPP or DOCD? 550.246 Section 550.246 Mineral Resources BUREAU OF OCEAN ENERGY... Operations Coordination Documents (docd) § 550.246 What mineral resource conservation information...

  5. CRYSTAL CHEMISTRY OF HYDROUS MINERALS

    SciTech Connect

    Y. ZHAO; ET AL

    2001-02-01

    Hydrogen has long been appreciated for its role in geological processes of the Earth's crust. However, its role in Earth's deep interior has been neglected in most geophysical thinking. Yet it is now believed that most of our planet's hydrogen may be locked up in high pressure phases of hydrous silicate minerals within the Earth's mantle. This rocky interior (approximately 7/8 of Earth's volume) is conjectured to contain 1-2 orders of magnitude more water than the more obvious oceans (the ''hydrosphere'') and atmosphere. This project is aimed at using the capability of neutron scattering from hydrogen to study the crystal chemistry and stability of hydrogen-bearing minerals at high pressures and temperatures. At the most basic level this is a study of the atomic position and hydrogen bond itself. We have conducted experimental runs on hydrous minerals under high pressure and high temperature conditions. The crystallographic structure of hydrous minerals at extreme conditions and its structural stability, and hydrogen bond at high P-T conditions are the fundamental questions to be addressed. The behavior of the hydrous minerals in the deep interior of the Earth has been discussed.

  6. Thermal expansion accompanying the glass-liquid transition and crystallization

    NASA Astrophysics Data System (ADS)

    Jiang, M. Q.; Naderi, M.; Wang, Y. J.; Peterlechner, M.; Liu, X. F.; Zeng, F.; Jiang, F.; Dai, L. H.; Wilde, G.

    2015-12-01

    We report the linear thermal expansion behaviors of a Zr-based (Vitreloy 1) bulk metallic glass in its as-cast, annealed and crystallized states. Accompanying the glass-liquid transition, the as-cast Vitreloy 1 shows a continuous decrease in the thermal expansivity, whereas the annealed glass shows a sudden increase. The crystallized Vitreloy 1 exhibits an almost unchanged thermal expansivity prior to its melting. Furthermore, it is demonstrated that the nucleation of crystalline phases can induce a significant thermal shrinkage of the supercooled liquid, but with the growth of these nuclei, the thermal expansion again dominates. These results are explained in the framework of the potential energy landscape, advocating that the configurational and vibrational contributions to the thermal expansion of the glass depend on both, structure and temperature.

  7. 30 CFR 250.246 - What mineral resource conservation information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... must accompany the DPP or DOCD? 250.246 Section 250.246 Mineral Resources BUREAU OF OCEAN ENERGY... information, as applicable, must accompany your DPP or DOCD: (a) Technology and reservoir engineering practices and procedures. A description of the technology and reservoir engineering practices and...

  8. Crystals: animal, vegetable or mineral?

    PubMed Central

    Hyde, Stephen T.

    2015-01-01

    The morphologies of biological materials, from body shapes to membranes within cells, are typically curvaceous and flexible, in contrast to the angular, facetted shapes of inorganic matter. An alternative dichotomy has it that biomolecules typically assemble into aperiodic structures in vivo, in contrast to inorganic crystals. This paper explores the evolution of our understanding of structures across the spectrum of materials, from living to inanimate, driven by those naive beliefs, with particular focus on the development of crystallography in materials science and biology. The idea that there is a clear distinction between these two classes of matter has waxed and waned in popularity through past centuries. Our current understanding, driven largely by detailed exploration of biomolecular structures at the sub-cellular level initiated by Bernal and Astbury in the 1930s, and more recent explorations of sterile soft matter, makes it clear that this is a false dichotomy. For example, liquid crystals and other soft materials are common to both living and inanimate materials. The older picture of disjoint universes of forms is better understood as a continuum of forms, with significant overlap and common features unifying biological and inorganic matter. In addition to the philosophical relevance of this perspective, there are important ramifications for science. For example, the debates surrounding extra-terrestrial life, the oldest terrestrial fossils and consequent dating of the emergence of life on the Earth rests to some degree on prejudices inferred from the supposed dichotomy between life-forms and the rest. PMID:26464788

  9. Experimental dynamic metamorphism of mineral single crystals

    USGS Publications Warehouse

    Kirby, S.H.; Stern, L.A.

    1993-01-01

    This paper is a review of some of the rich and varied interactions between non-hydrostatic stress and phase transformations or mineral reactions, drawn mainly from results of experiments done on mineral single crystals in our laboratory or our co-authors. The state of stress and inelastic deformation can enter explicitly into the equilibrium phase relations and kinetics of mineral reactions. Alternatively, phase transformations can have prominent effects on theology and on the nature of inelastic deformation. Our examples represent five types of structural phase changes, each of which is distinguished by particular mechanical effects. In increasing structural complexity, these include: (1) displacive phase transformations involving no bond-breaking, which may produce anomalous brittle behavior. A primary example is the a-?? quartz transition which shows anomalously low fracture strength and tertiary creep behavior near the transition temperature; (2) martensitic-like transformations involving transformation strains dominated by shear deformation. Examples include the orthoenstatite ??? clinoenstatite and w u ??rtzite ??? sphalerite transformations; (3) coherent exsolution or precipitation of a mineral solute from a supersaturated solid-solution, with anisotropy of precipitation and creep rates produced under nonhydrostatic stress. Examples include exsolution of corundum from MgO ?? nAl2O3 spinels and Ca-clinopyroxene from orthopyroxene; (4) order-disorder transformations that are believed to cause anomalous plastic yield strengthening, such as MgO - nAl2O3 spinels; and (5) near-surface devolatilization of hydrous silicate single-crystals that produces a fundamental brittleness thought to be connected with dehydration at microcracks at temperatures well below nominal macroscopic dehydration temperatures. As none of these interactions between single-crystal phase transformations and non-hydrostatic stress is understood in detail, this paper serves as a challenge to

  10. Inverse Slip Accompanying Twinning and Detwinning during Cyclic Loading of Magnesium Single Crystal

    DOE PAGESBeta

    Yu, Qin; Wang, Jian; Jiang, Yanyao

    2013-01-01

    In situ , observation of twinning and detwinning in magnesium single crystals during tension-compression cyclic loading was made using optical microscopy. A quantitative analysis of plastic strain indicates that twinning and detwinning experience two stages, low and high work hardening de-twinning, and pure re-twinning and fresh twinning combined with retwinning. Slip is always activated. For the first time, inverse slip accompanying with pure retwinning and high work hardening detwinning was experimentally identified, which provides insights in better understanding of the activity of twining, detwinning, and slips.

  11. The emission of atoms and molecules accompanying fracture of single-crystal MgO

    NASA Technical Reports Server (NTRS)

    Dickinson, J. T.; Jensen, L. C.; Mckay, M. R.; Freund, F.

    1986-01-01

    The emission of particles due to deformation and fracture of materials has been investigated. The emission of electrons (exoelectron emission), ions, neutral species, photons (triboluminescence), as well as long wavelength electromagnetic radiation was observed; collectively these emissions are referred to as fractoemission. This paper describes measurements of the neutral emission accompanying the fracture of single-crystal MgO. Masses detected are tentatively assigned to the emission of H2, CH4, H2O, CO, O2, CO2, and atomic Mg. Other hydrocarbons are also observed. The time dependencies of some of these emissions relative to fracture are presented for two different loading conditions.

  12. The Alaskan Mineral Resource Assessment Program; background information to accompany folio of geologic and mineral resource maps of the Talkeetna Quadrangle, Alaska

    USGS Publications Warehouse

    Reed, Bruce L.; Curtin, G.C.; Griscom, Andrew; Nelson, S.W.; Singer, D.A.; Steele, W.C.

    1979-01-01

    The Talkeetna 1? by 3? quadrangle, which consists of about 17,155 km 2 in south-central Alaska, was investigated by integrated field and laboratory studies in the disciplines of geology, geochemistry, geophysics, and Landsat data interpretation for the purpose of assessing its mineral resource potential. Past mineral production has been limited to gold from the Yentna district, but the quadrangle contains potentially significant resources of tin and silver and possibly a few other commodities including chromite and copper. The results of the mineral resource assessment are given in a folio of maps which are accompanied by descriptive texts, diagrams, tables, and pertinent references. This Circular provides background information on these investigations and integrates the component maps. A bibliography cites both specific and general references to the geology and mineral deposits of the quadrangle.

  13. Automated mineral identification algorithm using optical properties of crystals

    NASA Astrophysics Data System (ADS)

    Aligholi, Saeed; Khajavi, Reza; Razmara, Morteza

    2015-12-01

    A method has been developed to automatically characterize the type of mineral phases by means of digital image analysis using optical properties of crystals. The method relies on microscope automation, digital image acquisition, image processing and analysis. Two hundred series of digital images were taken from 45 standard thin sections using a digital camera mounted on a conventional microscope and then transmitted to a computer. CIELab color space is selected for the processing, in order to effectively employ its well-defined color difference metric for introducing appropriate color-based feature. Seven basic optical properties of minerals (A. color; B. pleochroism; C. interference color; D. birefringence; E. opacity; F. isotropy; G. extinction angle) are redefined. The Local Binary Pattern (LBP) operator and modeling texture is integrated in the Mineral Identification (MI) scheme to identify homogeneous regions in microscopic images of minerals. The accuracy of mineral identification using the method was %99, %98, %96 and %95 for biotite, hornblende, quartz and calcite minerals, respectively. The method is applicable to other minerals and phases for which individual optical properties of crystals do not provide enough discrimination between the relevant phases. On the basis of this research, it can be concluded that if the CIELab color space and the local binary pattern (LBP) are applied, it is possible to recognize the mineral samples with the accuracy of more than 98%.

  14. The Alaskan mineral resource assessment program; background information to accompany folio of geologic and mineral resource maps of the Nabesna Quadrangle, Alaska

    USGS Publications Warehouse

    Richter, Donald H.; Albert, N.R.D.; Barnes, D.F.; Griscom, Andrew; Marsh, S.P.; Singer, D.A.

    1975-01-01

    The Nabesna quadrangle in south-central Alaska is the first of the l:250,000-scale Alaskan quadrangles to be investigated by an interdisciplinary research team in order to furnish a mineral resource assessment of the State. The assessment of the 17,600-km 2 16,800-mi21 quadrangle is based on field and laboratory investigations of the geology, geochemistry, geophysics, and satellite imagery. The results of the investigations are published as a folio of maps, diagrams, and accompanying discussions. This report provides background information on the investigations and integrates the published components of the resource assessment. A comprehensive bibliography cites both specific and general references to the geology and mineral deposits of the Nabesna quadrangle.

  15. Mineral resource of the month: cultured quartz crystal

    USGS Publications Warehouse

    U.S. Geological Survey

    2008-01-01

    The article presents information on cultured quartz crystals, a mineral used in mobile phones, computers, clocks and other devices controlled by digital circuits. Cultured quartz, which is synthetically produced in large pressurized vessels known as autoclaves, is useful in electronic circuits for precise filtration, frequency control and timing for consumer and military use. Several ingredients are used in producing cultured quartz, including seed crystals, lascas, a solution of sodium hydroxide or sodium carbonate, lithium salts and deionized water.

  16. Phylogenetic significance of composition and crystal morphology of magnetosome minerals

    PubMed Central

    Pósfai, Mihály; Lefèvre, Christopher T.; Trubitsyn, Denis; Bazylinski, Dennis A.; Frankel, Richard B.

    2013-01-01

    Magnetotactic bacteria (MTB) biomineralize magnetosomes, nano-scale crystals of magnetite or greigite in membrane enclosures that comprise a permanent magnetic dipole in each cell. MTB control the mineral composition, habit, size, and crystallographic orientation of the magnetosomes, as well as their arrangement within the cell. Studies involving magnetosomes that contain mineral and biological phases require multidisciplinary efforts. Here we use crystallographic, genomic and phylogenetic perspectives to review the correlations between magnetosome mineral habits and the phylogenetic affiliations of MTB, and show that these correlations have important implications for the evolution of magnetosome synthesis, and thus magnetotaxis. PMID:24324461

  17. Phylogenetic significance of composition and crystal morphology of magnetosome minerals.

    PubMed

    Pósfai, Mihály; Lefèvre, Christopher T; Trubitsyn, Denis; Bazylinski, Dennis A; Frankel, Richard B

    2013-01-01

    Magnetotactic bacteria (MTB) biomineralize magnetosomes, nano-scale crystals of magnetite or greigite in membrane enclosures that comprise a permanent magnetic dipole in each cell. MTB control the mineral composition, habit, size, and crystallographic orientation of the magnetosomes, as well as their arrangement within the cell. Studies involving magnetosomes that contain mineral and biological phases require multidisciplinary efforts. Here we use crystallographic, genomic and phylogenetic perspectives to review the correlations between magnetosome mineral habits and the phylogenetic affiliations of MTB, and show that these correlations have important implications for the evolution of magnetosome synthesis, and thus magnetotaxis. PMID:24324461

  18. Lateral Packing of Mineral Crystals in Bone Collagen

    SciTech Connect

    Burger, C.; Zhou, H; Wang, H; Sics, I; Hsiao, B; Chu, B; Graham, L; Glimcher, M

    2008-01-01

    Combined small-angle x-ray scattering and transmission electron microscopy studies of intramuscular fish bone (shad and herring) indicate that the lateral packing of nanoscale calcium-phosphate crystals in collagen fibrils can be represented by irregular stacks of platelet-shaped crystals, intercalated with organic layers of collagen molecules. The scattering intensity distribution in this system can be described by a modified Zernike-Prins model, taking preferred orientation effects into account. Using the model, the diffuse fan-shaped small-angle x-ray scattering intensity profile, dominating the equatorial region of the scattering pattern, could be quantitatively analyzed as a function of the degree of mineralization. The mineral platelets were found to be very thin (1.5nm{approx}2.0nm), having a narrow thickness distribution. The thickness of the organic layers between adjacent mineral platelets within a stack is more broadly distributed with the average value varying from 6nm to 10nm, depending on the extent of mineralization. The two-dimensional analytical scheme also leads to quantitative information about the preferred orientation of mineral stacks and the average height of crystals along the crystallographic c axis.

  19. Manganese oxide minerals: Crystal structures and economic and environmental significance

    PubMed Central

    Post, Jeffrey E.

    1999-01-01

    Manganese oxide minerals have been used for thousands of years—by the ancients for pigments and to clarify glass, and today as ores of Mn metal, catalysts, and battery material. More than 30 Mn oxide minerals occur in a wide variety of geological settings. They are major components of Mn nodules that pave huge areas of the ocean floor and bottoms of many fresh-water lakes. Mn oxide minerals are ubiquitous in soils and sediments and participate in a variety of chemical reactions that affect groundwater and bulk soil composition. Their typical occurrence as fine-grained mixtures makes it difficult to study their atomic structures and crystal chemistries. In recent years, however, investigations using transmission electron microscopy and powder x-ray and neutron diffraction methods have provided important new insights into the structures and properties of these materials. The crystal structures for todorokite and birnessite, two of the more common Mn oxide minerals in terrestrial deposits and ocean nodules, were determined by using powder x-ray diffraction data and the Rietveld refinement method. Because of the large tunnels in todorokite and related structures there is considerable interest in the use of these materials and synthetic analogues as catalysts and cation exchange agents. Birnessite-group minerals have layer structures and readily undergo oxidation reduction and cation-exchange reactions and play a major role in controlling groundwater chemistry. PMID:10097056

  20. Hydrocarbon crystallization of life (conception of mineral organismobiosis)

    NASA Astrophysics Data System (ADS)

    Yushkin, N.

    Mineral world coexists in nature with the structurally ordered hydrocarbons. In spite of the fact that study of supermolecular ordering in solid hydrocarbons is at its dawn, nonbiogenic hydrocarbon organism-like forms have been found in many earthly and space objects. One prominent example is fibrous kerite crystals from crystallisation voids in pegmatites. Kerite crystals show fibrous and cylindrical habits, often with spheres at the ends and an internal axial channel. Spiral-like individuals twisted in one direction (left or right; chiral selection is carried out according to the epitaxial mechanism). The elemental composition of fibrous kerite crystals is almost identical to that of protein. They contain all chemical elements and all elements-catalysts. Heating the crystals in the range from twenty to six hundred Celsius resulted in release of a variety of hydrocarbon gases to the inner channels and environment. The crystals are distinguished by anomalously high contents of all "protein" amino acids, which are synthesized from abiogenic components during crystallisation. Protein self-assembly and evolution of some organismic functions described as biological ones are possible. We relied on fibrous kerite crystals to develop a model of a protobiological organism, genetic predecessor of biological life forms and to propose a concept of hydrocarbon crystallisation of life. That is structural-functional development of ordered molecular systems as protoorganisms that possess structural and functional elements of a protocell, a protogen, contain structural components of a protoprotein in the biological organisms. Life originated and evolved as a single whole, an integral sequence of crystallisation processes occurring in complex hydrocarbon systems, not as a result of random events and combination of genetically different components. Both minerals and organisms evolve governed by common ontogenetic laws.

  1. The Alaska Mineral Resource Assessment Program; background information to accompany geologic and mineral-resource maps of the Cordova and Middleton Island quadrangles, southern Alaska

    USGS Publications Warehouse

    Winkler, Gary R.; Plafker, George; Goldfarb, R.J.; Case, J.E.

    1992-01-01

    report summarizes recent results of integrated geological, geochemical, and geophysical field and laboratory studies conducted by the U.S. Geological Survey in the Cordova and Middleton Island 1?x3 ? quadrangles of coastal southern Alaska. Published open-file reports and maps accompanied by descriptive and interpretative texts, tables, diagrams, and pertinent references provide background information for a mineral-resource assessment of the two quadrangles. Mines in the Cordova and Middleton Island quadrangles produced copper and byproduct gold and silver in the first three decades of the 20th century. The quadrangles may contain potentially significant undiscovered resources of precious and base metals (gold, silver, copper, zinc, and lead) in veins and massive sulfide deposits hosted by Cretaceous and Paleogene sedimentary and volcanic rocks. Resources of manganese also may be present in the Paleogene rocks; uranium resources may be present in Eocene granitic rocks; and placer gold may be present in beach sands near the mouth of the Copper River, in alluvial sands within the canyons of the Copper River, and in smaller alluvial deposits underlain by rocks of the Valdez Group. Significant coal resources are present in the Bering River area, but difficult access and structural complexities have discouraged development. Investigation of numerous oil and gas seeps near Katalla in the eastern part of the area led to the discovery of a small, shallow field from which oil was produced between 1902 and 1933. The field has been inactive since, and subsequent exploration and drilling onshore near Katalla in the 1960's and offshore near Middleton Island on the outer continental shelf in the 1970's and 1980's was not successful.

  2. The effects of Raman scattering accompanied by the soliton excitation occurring in molecular crystals

    NASA Astrophysics Data System (ADS)

    Pang, X. F.

    2001-06-01

    A theoretical research is made for the effects of Raman scattering caused by the soliton excitation occurring in the organic molecular crystals, e.g., acetanilide, on the basis of vibration model of amide-I. The energy gap between the soliton state and the vibron state have been found by partial diagonalized method in second quantized representation, which is 18.1-33 cm -1. This result is approximately consistent with the red shift value obtained from the experiments, 16 cm -1. The differential cross-section of the Raman scattering, arising from the soliton excitation, has also been obtained. Finally, we derive some properties of the Raman scattering in such a case. This result establishes spectral signatures of the soliton in the molecular crystals, which may be observed in the experiment.

  3. Mineral licks: motivational factors for visitation and accompanying disease risk at communal use sites of elk and deer.

    PubMed

    Lavelle, Michael J; Phillips, Gregory E; Fischer, Justin W; Burke, Patrick W; Seward, Nathan W; Stahl, Randal S; Nichols, Tracy A; Wunder, Bruce A; VerCauteren, Kurt C

    2014-12-01

    Free-ranging cervids acquire most of their essential minerals through forage consumption, though occasionally seek other sources to account for seasonal mineral deficiencies. Mineral sources occur as natural geological deposits (i.e., licks) or as anthropogenic mineral supplements. In both scenarios, these sources commonly serve as focal sites for visitation. We monitored 11 licks in Rocky Mountain National Park, north-central Colorado, using trail cameras to quantify daily visitation indices (DVI) and soil consumption indices (SCI) for Rocky Mountain elk (Cervus elaphus) and mule deer (Odocoileus hemionus) during summer 2006 and documented elk, mule deer, and moose (Alces alces) visiting licks. Additionally, soil samples were collected, and mineral concentrations were compared to discern levels that explain rates of visitation. Relationships between response variables; DVI and SCI, and explanatory variables; elevation class, moisture class, period of study, and concentrations of minerals were examined. We found that DVI and SCI were greatest at two wet, low-elevation licks exhibiting relatively high concentrations of manganese and sodium. Because cervids are known to seek Na from soils, we suggest our observed association of Mn with DVI and SCI was a likely consequence of deer and elk seeking supplemental dietary Na. Additionally, highly utilized licks such as these provide an area of concentrated cervid occupation and interaction, thus increasing risk for environmental transmission of infectious pathogens such as chronic wasting disease, which has been shown to be shed in the saliva, urine, and feces of infected cervids. PMID:24711146

  4. Nanoscale Imaging of Mineral Crystals inside Biological Composite Materials Using X-Ray Diffraction Microscopy

    NASA Astrophysics Data System (ADS)

    Jiang, Huaidong; Ramunno-Johnson, Damien; Song, Changyong; Amirbekian, Bagrat; Kohmura, Yoshiki; Nishino, Yoshinori; Takahashi, Yukio; Ishikawa, Tetsuya; Miao, Jianwei

    2008-01-01

    We for the first time applied x-ray diffraction microscopy to the imaging of mineral crystals inside biological composite materials—intramuscular fish bone—at the nanometer scale resolution. We identified mineral crystals in collagen fibrils at different stages of mineralization. Based on the experimental results and biomineralization analyses, we suggested a dynamic model to account for the nucleation and growth of mineral crystals in the collagen matrix. The results obtained from this study not only further our understanding of the complex structure of bone, but also demonstrate that x-ray diffraction microscopy will become an important tool to study biological materials.

  5. The Conterminous United States Mineral Assessment Program; background information to accompany folio of geologic, geochemical, geophysical, and mineral resource maps of the Ajo and Lukeville 1 degree x 2 degrees quadrangles, Arizona

    USGS Publications Warehouse

    Gray, Floyd; Tosdal, R.M.; Peterson, J.A.; Cox, D.P.; Miller, R.J.; Klein, D.P.; Theobald, P.K.; Haxel, G.B.; Grubensky, M.J.; Raines, G.L.; Barton, H.N.; Singer, D.A.; Eppinger, R.G.

    1992-01-01

    Encompassing about 21,000 km 2 in southwestern Arizona, the Ajo and Lukeville 1 ? by 2 ? quadrangles have been the subject of mineral resource investigations utilizing field and laboratory studies in the disciplines of geology, geochemistry, geophysics, and Landsat imagery. The results of these studies are published as a folio of maps, figures, and tables, with accompanying discussions. Past mineral production has been limited to copper from the Ajo Mining District. In addition to copper, the quadrangles contain potentially significant resources of gold and silver; a few other commodities, including molybdenum and evaporites, may also exist in the area as appreciable resources. This circular provides background information on the mineral deposits and on the investigations and integrates the information presented in the folio. The bibliography cites references to the geology, geochemistry, geophysics, and mineral deposits of the two quadrangles.

  6. The Conterminous United States Mineral Appraisal Program; background information to accompany folio of geologic, geochemical, geophysical, and mineral resources maps of the Tonopah 1 by 2 degree Quadrangle, Nevada

    USGS Publications Warehouse

    John, David A.; Nash, J.T.; Plouff, Donald; Whitebread, D.H.

    1991-01-01

    The Tonopah 1 ? by 2 ? quadrangle in south-central Nevada was studied by an interdisciplinary research team to appraise its mineral resources. The appraisal is based on geological, geochemical, and geophysical field and laboratory investigations, the results of which are published as a folio of maps, figures, and tables, with accompanying discussions. This circular provides background information on the investigations and integrates the information presented in the folio. The selected bibliography lists references to the geology, geochemistry, geophysics, and mineral deposits of the Tonopah 1 ? by 2 ? quadrangle.

  7. The Conterminous United States Mineral Assessment Project; background information to accompany folio of geologic, geochemical, geophysical, and mineral resources maps of the Reno 1 by 2 degree Quadrangle, Nevada and California

    USGS Publications Warehouse

    John, David A.; Stewart, John H.; Hendricks, J.D.; Rowan, L.C.; Plouff, Donald

    1992-01-01

    The Reno 1 ? by 2 ? quadrangle in west-central Nevada was studied by an interdisciplinary research team to appraise its mineral resources. The assessment is based on geological, geochemical, and geophysical field and laboratory investigations, the results of which are published as a folio of maps, reports, figures, and tables, with accompanying discussions. This circular provides background information on the investigations and integrates the information presented in the folio. The selected bibliography lists references to the geology, geochemistry, geophysics, and mineral deposits of the Reno 1 ? by 2 ? quadrangle.

  8. The Conterminous United States Mineral Appraisal Program; background information to accompany folio of geologic, geochemical, geophysical, and mineral resources maps of the Walker Lake 1 degree x 2 degrees Quadrangle, California and Nevada

    USGS Publications Warehouse

    Stewart, John Harris; Chaffee, M.A.; Dohrenwend, J.C.; John, D.A.; Kistler, R.W.; Kleinhampl, F.J.; Menzie, W.D.; Plouff, Donald; Rowan, L.C.; Silberling, Norman J.

    1984-01-01

    The Walker Lake 1? by 2? quadrangle in eastern California and western Nevada was studied by an interdisciplinary research team to appraise its mineral resources. The appraisal is based on geological, geochemical, and geophysical field and laboratory investigations, the results of which are published as a folio of maps, figures, and tables, with accompanying discussions. This circular provides background information on the investigations and integrates the information presented in the folio. The selected bibliography lists selected references to the geology, geochemistry, geophysics, and mineral deposits of the Walker Lake 1? by 2? quadrangle.

  9. The Conterminous United States Mineral Appraisal Program; background information to accompany folio of geologic, geochemical, geophysical, and mineral resources maps of the Medford 1 degree x 2 degrees Quadrangle, Oregon and California

    USGS Publications Warehouse

    Smith, James G.; Blakely, R.J.; Johnson, M.G.; Page, N.J.; Peterson, J.A.; Singer, D.A.; Whittington, C.L.

    1986-01-01

    The Medford 1 ? by 2 ? quadrangle in southern Oregon and northern California was studied by an interdisciplinary research team to appraise its mineral resources. The appraisal is based on geological, geochemical, and geophysical field and laboratory investigations, the results of which are published as a folio of maps, figures, and tables, with accompanying discussions. This circular provides background information on the investigations and integrates the information presented in the folio. The bibliography lists selected references to the geology, geochemistry, geophysics, and mineral deposits of the Medford 1 ? by 2 ? quadrangle.

  10. The Conterminous United States Mineral Appraisal Program; background information to accompany folio of geologic, geochemical, geophysical, and mineral resource maps of the Choteau 1 degree x 2 degrees Quadrangle, Montana

    USGS Publications Warehouse

    Earhart, Robert L.; Grimes, David J.; Leinz, Reinhard W.; Kleinkopf, M. Dean

    1981-01-01

    The Choteau l? x 2? quadrangle in northwest Montana was studied by an interdisciplinary research team in order to appraise its mineral resource and hydrocarbon potential The appraisal is based on field and laboratory investigations of the geology, geochemistry, and geophysics. The results of the investigations are published as a folio of maps, figures, tables, and accompanying discussions. This circular provides background information on the investigations and integrates the published components of the resource appraisal. A comprehensive bibliography cites both specific and general references to the geology, geochemistry, geophysics, and mineral deposits of the Choteau l? x 2? quadrangle.

  11. Crystal-Chemical Analysis Martian Minerals in Gale Crater

    NASA Technical Reports Server (NTRS)

    Morrison, S. M.; Downs, R. T.; Blake, D. F.; Bish, D. L.; Ming, D. W.; Morris, R. V.; Yen, A. S.; Chipera, S. J.; Treiman, A. H.; Vaniman, D. T.; Gellert, R.; Achilles, C. N..; Rampe, E. B.; Bristow, T. F.; Crisp, J. A.; Sarrazin, P. C.; Farmer, J. D.; DesMarais, D. J.; Grotzinger, J. P.; Stolper, E. M.; Morookian, J. M.; Wilson, M. A.; Spanovich, N.; Anderson, R. C.

    2015-01-01

    The CheMin instrument on the Mars Science Laboratory rover Curiosity performed X-ray diffraction analyses on scooped soil at Rocknest and on drilled rock fines at Yellowknife Bay (John Klein and Cumberland samples), The Kimberley (Windjana sample), and Pahrump (Confidence Hills sample) in Gale crater, Mars. Samples were analyzed with the Rietveld method to determine the unit-cell parameters and abundance of each observed crystalline phase. Unit-cell parameters were used to estimate compositions of the major crystalline phases using crystal-chemical techniques. These phases include olivine, plagioclase and clinopyroxene minerals. Comparison of the CheMin sample unit-cell parameters with those in the literature provides an estimate of the chemical compositions of the major crystalline phases. Preliminary unit-cell parameters, abundances and compositions of crystalline phases found in Rocknest and Yellowknife Bay samples were reported in. Further instrument calibration, development of 2D-to- 1D pattern conversion corrections, and refinement of corrected data allows presentation of improved compositions for the above samples.

  12. Crystal Structure and Crystal Chemistry of Some Common REE Minerals and Nanpingite

    NASA Astrophysics Data System (ADS)

    Ni, Yunxiang

    1995-01-01

    Part I. Crystal structure and crystal chemistry of fluorocarbonate minerals. The crystal structure of bastnasite-(Ce) have been solved in P-62c and refined to R = 0.018. The structure is composed of (001) (CeF) layers interspersed with (CO_3) layers in a 1:1 ratio. The Ce atom is coordinated in rm CeO_6F_3 polyhedra. The atomic arrangement of synchysite-(Ce) has been solved and refined to R = 0.036 with a monoclinic space group C2/c. It possesses a (001) layer structure, with layers of (Ca) and (CeF) separated by layers of carbonate groups. The layers stack in a manner analogous to C2/c muscovite. Polytypism similar to the micas may exist in synchysite. The crystal structures of cordylite-(Ce) have been solved in P6 _3/mmc and refined to R = 0.023. The structure and chemical formula are different from those deduced by Oftedal. The formula is rm MBaCe_2(CO _3)_4F, where M is rm Na^+, Ca^{2+}_{1/2 }+ O_{1/2}, or any solution. The presence of (NaF) layer in the structure is the key difference from the Oftedal's structure. This redefinition of the chemical formula and crystal structure of cordylite will be proposed to IMA-CNMMN. Part II. Crystal structure and crystal chemistry of monazite-xenotime series. Monazite is monoclinic, P2 _1/n, and xenotime is isostructural with zircon (I4_1/amd). Both atomic arrangements are based on (001) chains of intervening phosphate tetrahedra and RE polyhedra, with a REO_8 polyhedron in xenotime that accommodates HRE (Tb - Lu) and a REO_9 polyhedron in monazite that preferentially incorporates LRE (La - Gd). As the structure "transforms" from xenotime to monazite, the crystallographic properties are comparable along the (001) chains, with structural adjustments of 2.2 A along (010) to accommodate the different size RE atoms. Part III. Crystal structure of nanpingite-2M _2, the Cs end-member of muscovite. The crystal structure of nanpingite has been refined to R = 0.058. Compared to K^+ in muscovite, the largest interlayer Cs^+ in

  13. Mineral crystal alignment in mineralized fracture callus determined by 3D small-angle X-ray scattering

    NASA Astrophysics Data System (ADS)

    Liu, Yifei; Manjubala, Inderchand; Roschger, Paul; Schell, Hanna; Duda, Georg N.; Fratzl, Peter

    2010-10-01

    Callus tissue formed during bone fracture healing is a mixture of different tissue types as revealed by histological analysis. But the structural characteristics of mineral crystals within the healing callus are not well known. Since two-dimensional (2D) scanning small-angle X-ray scattering (sSAXS) patterns showed that the size and orientation of callus crystals vary both spatially and temporally [1] and 2D electron microscopic analysis implies an anisotropic property of the callus morphology, the mineral crystals within the callus are also expected to vary in size and orientation in 3D. Three-dimensional small-angle X-ray scattering (3D SAXS), which combines 2D SAXS patterns collected at different angles of sample tilting, has been previously applied to investigate bone minerals in horse radius [2] and oim/oim mouse femur/tibia [3]. We implement a similar 3D SAXS method but with a different way of data analysis to gather information on the mineral alignment in fracture callus. With the proposed accurate yet fast assessment of 3D SAXS information, it was shown that the plate shaped mineral particles in the healing callus were aligned in groups with their predominant orientations occurring as a fiber texture.

  14. The Conterminous United States Mineral Assessment Program; background information to accompany folio of geologic, geochemical, remote sensing, and mineral resources maps of the Butte 1 degree x 2 degrees Quadrangle, Montana

    USGS Publications Warehouse

    Elliott, James E.; Trautwein, C.M.; Wallace, C.A.; Lee, G.K.; Rowan, L.C.; Hanna, W.F.

    1993-01-01

    The Butte 1?x2 ? quadrangle in west-central Montana was investigated as part of the U.S. Geological Survey's Conterminous United States Mineral Assessment Program (CUSMAP). These investigations included geologic mapping, geochemical surveys, gravity and aeromagnetic surveys, examinations of mineral deposits, and specialized geochronologic and remote-sensing studies. The data collected during these studies were compiled, combined with available published and unpublished data, analyzed, and used in a mineral-resource assessment of the quadrangle. The results, including data, interpretations, and mineral-resource assessments for nine types of mineral deposits, are published separately as a folio of maps. These maps are accompanied by figures, tables, and explanatory text. This circular provides background information on the Butte quadrangle, summarizes the studies and published maps, and lists a selected bibliography of references pertinent to the geology, geochemistry, geophysics, and mineral resources of the quadrangle. The Butte quadrangle, which includes the world-famous Butte mining district, has a long history of mineral production. Many mining districts within the quadrangle have produced large quantities of many commodities; the most important in dollar value of production were copper, gold, silver, lead, zinc, manganese, molybdenum, and phosphate. At present, mines at several locations produce copper, molybdenum, gold, silver, lead, zinc, and phosphate. Exploration, mainly for gold, has indicated the presence of other mineral deposits that may be exploited in the future. The results of the investigations by the U.S. Geological Survey indicate that many areas of the quadrangle are highly favorable for the occurrence of additional undiscovered resources of gold, silver, copper, molybdenum, tungsten, and other metals in several deposit types.

  15. The Alaskan Mineral Resource Assessment Program; background information to accompany folio of geologic and mineral resource maps of the Big Delta Quadrangle, Alaska

    USGS Publications Warehouse

    Foster, Helen Laura; Albert, N.R.D.; Griscom, Andrew; Hessin, T.D.; Menzie, W.D.; Turner, D.L.; Wilson, F.H.

    1979-01-01

    The geology, geochemistry, geophysics, and Landsat imagery of the Big Delta quadrangle, 16,335 km 2 in the Yukon-Tanana Upland of east-central Alaska, were investigated, and maps and reports were prepared by an interdisciplinary research team for the purpose of assessing the mineral potential. The quadrangle is dominantly a complex terrane of greenschist- to amphibolitefacies metamorphic rocks that have been intruded by Mesozoic and Tertiary dioritic to granitic rocks and are overlain by Tertiary sedimentary and volcanic rocks. Serpentinized peridotite and associated greenstone, graywacke, and chert crop out in some places. The quadrangle is bisected by the northeastward-trending Shaw Creek fault, which, on the basis of aeromagnetic interpretation and geologic data, is postulated to have left-lateral offset of as much as 48 km. On the northwest side of the Shaw Creek fault, metamorphic rock units have a northwesterly regional trend, and the oldest rocks could be Precambrian in age. Gneiss and schist in the southwestern part of the quadrangle are derived from both igneous and sedimentary protoliths, some of which may be as old as Precambrian. Other rock units, which include calcareous schist and thin-layered marble, black quartzite, semischist, and cataclastic rocks, are considered to be of probable Paleozoic age, although no fossils have yet been found in these rocks. Radiolarians and conodonts in chert associated with greenstone and ultramafic rocks indicate that the chert is of Permian age. Potassium-argon ages on igneous rocks of the Big Delta quadrangle fall into two groups: those with biotite, muscovite, hornblende, and sanidine ages between 50 to 69 m.y.; and those with biotite, hornblende, and sanidine ages between 88 to 105 m.y. The younger of these two groups appears to indicate the time of a plutonic event marked by intrusion of mostly small, isolated plutons, including hypabyssal stocks, and the eruption of silicic volcanic rocks. Most of the plutons are

  16. Minerals

    MedlinePlus

    Minerals are important for your body to stay healthy. Your body uses minerals for many different jobs, including building bones, making ... regulating your heartbeat. There are two kinds of minerals: macrominerals and trace minerals. Macrominerals are minerals your ...

  17. Bone mineral crystal size and organization vary across mature rat bone cortex.

    PubMed

    Turunen, Mikael J; Kaspersen, Jørn D; Olsson, Ulf; Guizar-Sicairos, Manuel; Bech, Martin; Schaff, Florian; Tägil, Magnus; Jurvelin, Jukka S; Isaksson, Hanna

    2016-09-01

    The macro- and micro-features of bone can be assessed by using imaging methods. However, nano- and molecular features require more detailed characterization, such as use of e.g., vibrational spectroscopy and X-ray scattering. Nano- and molecular features also affect the mechanical competence of bone tissue. The aim of the present study was to reveal the effects of mineralization and its alterations on the mineral crystal scale, by investigating the spatial variation of molecular composition and mineral crystal structure across the cross-section of femur diaphyses in young rats, and healthy and osteoporotic mature rats (N=5). Fourier transform infrared spectroscopy and scanning small- and wide-angle X-ray scattering (SAXS/WAXS) techniques with high spatial resolution were used at identical locations over the whole cross-section. This allowed quantification of point-by-point information about the spatial distribution of mineral crystal volume. All measured parameters (crystal dimensions, degree of orientation and predominant orientation) varied across the cortex. Specifically, the crystal dimensions were lower in the central cortex than in the endosteal and periosteal regions. Mineral crystal orientation followed the cortical circumference in the periosteal and endosteal regions, but was less well-oriented in the central regions. Central cortex is formed rapidly during development through endochondral ossification. Since rats possess no osteonal remodeling, this bone remains (until old age). Significant linear correlations were observed between the dimensional and organizational parameters, e.g., between crystal length and degree of orientation (R(2)=0.83, p<0.001). Application of SAXS/WAXS provides valuable information on bone nanostructure and its constituents, effects of diseases and, prospectively, mechanical competence. PMID:27417019

  18. The use of mineral crystals as bio-markers in the search for life on Mars

    NASA Technical Reports Server (NTRS)

    Schwartz, D. E.; Mancinelli, R. L.; Kaneshiro, E. S.

    1992-01-01

    It is proposed that minerals resulting from biologically controlled mineralization processes be utilized as biomarkers because of their favorable qualities. Universal signatures of life (biomarkers) are discussed in terms of their terrestrial forms and hypothetical Martian counterparts including organics, suites of specific inorganic and organic compounds, and isotopic ratios. It is emphasized that minerals produced under biologic control have morphological and isotopic compositions that are not found in their abiotic counterparts. Other biomarkers are not necessarily indicative of biological origin and are therefore unreliable resources for scientific study. Mineral crystals are also stable over long geological periods, and the minerals from Martian fluvial features can therefore be employed to search for fossils and biomarkers of early biological activity.

  19. Application of Membrane Crystallization for Minerals' Recovery from Produced Water.

    PubMed

    Ali, Aamer; Quist-Jensen, Cejna Anna; Macedonio, Francesca; Drioli, Enrico

    2015-01-01

    Produced water represents the largest wastewater stream from oil and gas production. Generally, its high salinity level restricts the treatment options. Membrane crystallization (MCr) is an emerging membrane process with the capability to extract simultaneously fresh water and valuable components from various streams. In the current study, the potential of MCr for produced water treatment and salt recovery was demonstrated. The experiments were carried out in lab scale and semi-pilot scale. The effect of thermal and hydrodynamic conditions on process performance and crystal characteristics were explored. Energy dispersive X-ray (EDX) and X-ray diffraction (XRD) analyses confirmed that the recovered crystals are sodium chloride with very high purity (>99.9%), also indicated by the cubic structure observed by microscopy and SEM (scanning electron microscopy) analysis. It was demonstrated experimentally that at recovery factor of 37%, 16.4 kg NaCl per cubic meter of produced water can be recovered. Anti-scaling surface morphological features of membranes were also identified. In general, the study provides a new perspective of isolation of valuable constituents from produced water that, otherwise, is considered as a nuisance. PMID:26610581

  20. A case of Fanconi syndrome accompanied by crystal depositions in tubular cells in a patient with multiple myeloma

    PubMed Central

    Kim, Do Hee; Lim, A Young; Gwag, Hye Bin; Lee, Ji Hyeon; Jung, Ki Sun; Lee, Keol; Huh, Wooseong; Kim, Dae Joong; Kim, Yoon-Goo; Oh, Ha Young; Kim, Kihyun; Kwon, Gee-Young; Lee, Jung Eun

    2014-01-01

    Fanconi syndrome (FS) is a rare condition that is characterized by defects in the proximal tubular function. A 48-year-old woman was admitted for evaluation of proteinuria. The patient showed normal anion gap acidosis, normoglycemic glycosuria, hypophosphatemia, and hypouricemia. Thus, her condition was compatible with FS. The M peak was found behind the beta globulin region in urine protein electrophoresis. Upon bone marrow examination, we found that 24% of cells were CD138+ plasma cells with kappa restriction. From a kidney biopsy, we found crystalline inclusions within proximal tubular epithelial cells. Thereafter, she was diagnosed with FS accompanied by multiple myeloma. The patient received chemotherapy and autologous stem cell transplantation, and obtained very good partial hematologic response. However, proximal tubular dysfunction was persistent until 1 year after autologous stem cell transplantation. In short, we report a case of FS accompanied by multiple myeloma, demonstrating crystalline inclusion in proximal tubular cells on kidney biopsy. PMID:26877961

  1. Identification of secondary minerals crystallized by low and high temperature alteration in the Northern Kyushu-Palau Ridge volcanic rocks

    NASA Astrophysics Data System (ADS)

    Haraguchi, S.

    2008-12-01

    characteristics of bulk composition of the Nichinan Seamount rocks are assumed similarity to primary signature. On the other hand, the Komahashi-Daini Seamount samples show completely re-crystallization, and igneous textures are observed to pseudomorph. These are identified by XRD to be quartz, clinochlore (one of chlorite), and albite. Secondary mineral assemblage is homogeneous in these rocks. The temperature of replacement by chlorite accompanied by enrichment in MgO is estimated to be more than 150°C on the basis of experimental studies (e.g. Mottle 1983). And interpreted two types of albitization, low temperature (< 50°C) and high temperature (> 100°C), are identified on the basis of study of ODP Leg 123 Site 765 igneous rocks (Gillis et al. 1992). Therefore, it is considered that volcanic rocks from the Komahashi-Daini Seamount were under effect of hydrothermal alteration more than 150°C. Many elements show significant movement under high temperature hydrothermal alteration (e.g. Laverne et al. 1996). That is, re-crystallization of chlorite under high temperature hydrothermal alteration accompanied addition of magnesium from seawater and remarkable bulk MgO enrichment (e.g. Nakamura, 2001). Therefore, it is considered that the Komahashi-Daini Seamount rocks show significant MgO-enrichment because of secondary mineralization of chlorite, and assumed to significant movement of other elements. These observations suggest that geochemical investigation of highly altered rocks must be made with caution.

  2. Orientational bonding of phases accompanying directed crystallization of the eutectic of the system Si-TiSi2

    NASA Astrophysics Data System (ADS)

    Derevyagina, L. S.; Butkevich, L. M.

    1987-09-01

    The characteristic features of structure formation in cast and direct crystallized alloys of the system Si-TiSi2 were studied. It is shown that the predominant orientation of the bonding of the phases in directionally crystallized eutectics (DE) of the system Si-TiSi2, observed at the stage of steady-state growth, already appears on the surface of nucleation, which apparently indicates that the nucleation of the phases in the alloys of this system is of an epitaxial character.

  3. Crystallization and textural porosity of synthetic clay minerals.

    SciTech Connect

    Carrado, K. A.; Csencsits, R.; Thiyagarajan, P.; Seifert, S.; Macha, S. M.; Harwood, J.; Univ. of Illinois at Chicago; IIT

    2002-12-01

    The crystallization of synthetic layered magnesium silicate hectorite clays from both silica sol and organosilane sources is compared. For the silica sol-derived clays, a templating method is employed wherein organic or polymeric molecules are included during clay crystallization that are then removed from the composites via calcination. The mechanism of silane-derived hectorite formation is followed by XRD, TGA, 29Si MAS NMR, and small angle X-ray scattering (SAXS), and results are compared to those obtained for the sol-derived hectorite. The mechanism appears to be similar but the rate is approximately doubled when the silane is used rather than silica sol. Analytical transmission electron microscopy (TEM) is exploited to glean structural morphology information towards resolving the nature of the resulting pore network structures. Results are compared with nitrogen adsorption-desorption isotherm behavior; dominant hysteresis loops are present in the type IV isotherms. Pore size distributions based on both the adsorption and desorption isotherms are compared. Small angle neutron scattering (SANS) experiments reveal that the average particle size increases as synthetic laponite < sol-derived hectorite < silane-derived hectorite < natural hectorite. Contrast matching SANS studies in aqueous and organic solvents are carried out to extract information about pore accessibility.

  4. Linked reactivity at mineral-water interfaces through bulk crystal conduction.

    PubMed

    Yanina, Svetlana V; Rosso, Kevin M

    2008-04-11

    The semiconducting properties of a wide range of minerals are often ignored in the study of their interfacial geochemical behavior. We show that surface-specific charge density accumulation reactions combined with bulk charge carrier diffusivity create conditions under which interfacial electron transfer reactions at one surface couple with those at another via current flow through the crystal bulk. Specifically, we observed that a chemically induced surface potential gradient across hematite (alpha-Fe2O3) crystals is sufficiently high and the bulk electrical resistivity sufficiently low that dissolution of edge surfaces is linked to simultaneous growth of the crystallographically distinct (001) basal plane. The apparent importance of bulk crystal conduction is likely to be generalizable to a host of naturally abundant semiconducting minerals playing varied key roles in soils, sediments, and the atmosphere. PMID:18323417

  5. Cell adhesion of Shewanella oneidensis to iron oxide minerals: Effect of different single crystal faces

    PubMed Central

    Neal, Andrew L; Bank, Tracy L; Hochella, Michael F; Rosso, Kevin M

    2005-01-01

    The results of experiments designed to test the hypothesis that near-surface molecular structure of iron oxide minerals influences adhesion of dissimilatory iron reducing bacteria are presented. These experiments involved the measurement, using atomic force microscopy, of interaction forces generated between Shewanella oneidensis MR-1 cells and single crystal growth faces of iron oxide minerals. Significantly different adhesive force was measured between cells and the (001) face of hematite, and the (100) and (111) faces of magnetite. A role for electrostatic interactions is apparent. The trend in relative forces of adhesion generated at the mineral surfaces is in agreement with predicted ferric site densities published previously. These results suggest that near-surface structure does indeed influence initial cell attachment to iron oxide surfaces; whether this is mediated via specific cell surface-mineral surface interactions or by more general interfacial phenomena remains untested.

  6. Crystal chemistry of hydroxyl and water in silicate minerals. Final technical report

    SciTech Connect

    Smyth, J.R.

    1998-06-01

    This was a project to investigate the crystal chemistry of OH and H{sub 2}O substitution in silicate minerals by use of X-ray and neutron diffraction methods combined with IR spectroscopy and to interpret and generalize the results using an electrostatic model for these mineral structures. Using these data together with published H position data electrostatic parameters for H sites were calculated from a simple electrostatic model. The data were then used to refine the model for incorporation of H into the wadsleyite structure. This has led to recent work on the synthesis and characterization of hydrous wadsleyites.

  7. Distinctive Accessory Minerals, Textures and Crystal Habits in Biofilm Associated Gypsum Deposits

    NASA Astrophysics Data System (ADS)

    Vogel, M.; Des Marais, D.; Jahnke, L.; Parenteau, M.

    2008-12-01

    Gypsum-depositing environments near Guerrero Negro, Baja California Sur, Mexico were investigated in order to differentiate the influence of microbial activity versus nonbiological processes upon sedimentary fabrics and minerals. Field sites were located in sabkhas (mudflats and anchialine pools) and in seawater concentration ponds in the salt production facility operated by Exportadora de Sal, S. A. Gypsum (CaSO4.2H2O) was classified according to sedimentary environment (e.g., mudflats, anchialine pools, saltern ponds, surface and subsurface sediments), sedimentary texture, mineral composition, crystal habit, brine composition and other geochemical and biological factors. Gypsum types that develop in the absence of biofilms include water column precipitates (pelagic grains) and subsedimentary crystalline discs that form from phreatic brine ripening. Subsedimentary gypsum forming in sabkha environments had a sinuous axial microtexture and poikilitically enclosed detrital particles whereas water column precipitates exhibited euhedral prismatic habits and extensive penetrative twinning. Gypsum that was influenced by biofilms included cumulate crusts and gypsooids / gypsolite developing in anchialine pools and in saltern concentration ponds. Gypsum precipitating within subaqueous benthic microbial mats, or biofilm/sediment surfaces offered compelling evidence of biofilm influence on crystal textures and habits. Biofilm effects include irregular high relief surface textures, accessory minerals (elemental sulfur, Ca-carbonate, Sr/Ca-sulfate, Mg-oxide and Mg- sulfate) and distinctive crystal habits. Elemental sulfur, Ca-carbonate, and Sr/Ca-sulfate are known byproducts of bacterially mediated sulfate reduction (BSR). Populations of gypsum crystals within biofilms exhibited euhedral to lensoidal morphologies with unique equant and distorted prismatic forms. These forms had been shown to arise from form- and face-specific inhibition by bioorganic functional groups (Cody

  8. Evolution of major mineral compositions and trace element abundances during fractional crystallization of a model lunar composition

    NASA Technical Reports Server (NTRS)

    Drake, M. J.

    1976-01-01

    The evolution of major mineral compositions and trace element abundances during perfect fractional crystallization of a model lunar magma ocean was calculated. The minerals in the model lunar composition were olivine, orthopyroxene, clinopyroxene, and plagioclase. Lunar bulk composition data, major mineral/melt equilibria data, and trace element partition data were taken from published sources. The results show olivine beginning to crystallize at 1380 C. Approximately 50% of the system crystallizes as olivine. From 50 to 60% solidification, orthopyroxene crystallizes alone. During the final 40% solidification, Ca-rich clinopyroxene and plagioclase crystallize together. Various changes in composition of all these minerals are also noted during the process. Concomitant evolution of major element abundances in the melt is followed along with that of trace element abundances. Consequences of the results for constraints on some aspects of the composition of the lunar magma ocean and of the primitive moon are discussed.

  9. Morphological Analysis of White Cement Clinker Minerals: Discussion on the Crystallization-Related Defects

    PubMed Central

    Benmohamed, Mohamed; Alouani, Rabah; Jmayai, Amel; Ben Haj Amara, Abdesslem; Ben Rhaiem, Hafsia

    2016-01-01

    The paper deals with a formation of artificial rock (clinker). Temperature plays the capital role in the manufacturing process. So, it is useful to analyze a poor clinker to identify the different phases and defects associated with their crystallization. X-ray fluorescence spectroscopy was used to determine the clinker's chemical composition. The amounts of the mineralogical phases are measured by quantitative XRD analysis (Rietveld). Scanning electron microscopy (SEM) was used to characterize the main phases of white Portland cement clinker and the defects associated with the formation of clinker mineral elements. The results of a study which focused on the identification of white clinker minerals and defects detected in these noncomplying clinkers such as fluctuation of the amount of the main phases (alite (C3S) and belite (C2S)), excess of the free lime, occurrence of C3S polymorphs, and occurrence of moderately-crystallized structures are presented in this paper. PMID:27313617

  10. Morphological Analysis of White Cement Clinker Minerals: Discussion on the Crystallization-Related Defects.

    PubMed

    Benmohamed, Mohamed; Alouani, Rabah; Jmayai, Amel; Ben Haj Amara, Abdesslem; Ben Rhaiem, Hafsia

    2016-01-01

    The paper deals with a formation of artificial rock (clinker). Temperature plays the capital role in the manufacturing process. So, it is useful to analyze a poor clinker to identify the different phases and defects associated with their crystallization. X-ray fluorescence spectroscopy was used to determine the clinker's chemical composition. The amounts of the mineralogical phases are measured by quantitative XRD analysis (Rietveld). Scanning electron microscopy (SEM) was used to characterize the main phases of white Portland cement clinker and the defects associated with the formation of clinker mineral elements. The results of a study which focused on the identification of white clinker minerals and defects detected in these noncomplying clinkers such as fluctuation of the amount of the main phases (alite (C3S) and belite (C2S)), excess of the free lime, occurrence of C3S polymorphs, and occurrence of moderately-crystallized structures are presented in this paper. PMID:27313617

  11. Minerals

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fish require the same minerals or inorganic elements as terrestrial animals for tissue formation, osmoregulation and various metabolic functions. Those required in large quantities are termed macro- or major minerals and those required in small quantities are called micro- or trace minerals. Fish ca...

  12. From crystal to glass-like thermal conductivity in crystalline minerals.

    PubMed

    Bouyrie, Y; Candolfi, C; Pailhès, S; Koza, M M; Malaman, B; Dauscher, A; Tobola, J; Boisron, O; Saviot, L; Lenoir, B

    2015-08-14

    The ability of some materials with a perfectly ordered crystal structure to mimic the heat conduction of amorphous solids is a remarkable physical property that finds applications in numerous areas of materials science, for example, in the search for more efficient thermoelectric materials that enable to directly convert heat into electricity. Here, we unveil the mechanism in which glass-like thermal conductivity emerges in tetrahedrites, a family of natural minerals extensively studied in geology and, more recently, in thermoelectricity. By investigating the lattice dynamics of two tetrahedrites of very close compositions (Cu12Sb2Te2S13 and Cu10Te4S13) but with opposite glasslike and crystal thermal transport by means of powder and single-crystal inelastic neutron scattering, we demonstrate that the former originates from the peculiar chemical environment of the copper atoms giving rise to a strongly anharmonic excess of vibrational states. PMID:26109211

  13. Dynamics of mineral crystallization from precipitated slab-derived fluid phase: first in situ synchrotron X-ray measurements

    NASA Astrophysics Data System (ADS)

    Malaspina, Nadia; Alvaro, Matteo; Campione, Marcello; Wilhelm, Heribert; Nestola, Fabrizio

    2015-03-01

    Remnants of the fluid phase at ultrahigh pressure (UHP) in subduction environments may be preserved as primary multiphase inclusions in UHP minerals. The mode of crystallization of daughter minerals during precipitation within the inclusion and/or the mechanism of interaction between the fluid at supercritical conditions and the host mineral are still poorly understood from a crystallographic point of view. A case study is represented by garnet-orthopyroxenites from the Maowu Ultramafic Complex (China) deriving from harzburgite precursors metasomatized at ~4 GPa, 750 °C by a silica- and incompatible trace element-rich fluid phase. This metasomatism produced poikilitic orthopyroxene and inclusion-rich garnet porphyroblasts. Solid multiphase primary inclusions in garnet display a size within a few tens of micrometres and negative crystal shapes. Infilling minerals (spinel: 10-20 vol%; amphibole, chlorite, talc, mica: 80-90 vol%) occur with constant volume proportions and derive from trapped solute-rich aqueous fluids. To constrain the possible mode of precipitation of daughter minerals, we performed for the first time a single-crystal X-ray diffraction experiment by synchrotron radiation at Diamond Light Source. In combination with electron probe microanalyses, this measurement allowed the unique identification of each mineral phase and reciprocal orientations. We demonstrated the epitaxial relationship between spinel and garnet and between some hydrous minerals. Such information is discussed in relation to the physico-chemical aspects of nucleation and growth, shedding light on the mode of mineral crystallization from a fluid phase trapped at supercritical conditions.

  14. Crystallization of urine mineral components may depend on the chemical nature of Proteus endotoxin polysaccharides.

    PubMed

    Torzewska, Agnieszka; Staczek, Paweł; Rózalski, Antoni

    2003-06-01

    Formation of infectious urinary calculi is the most common complication accompanying urinary tract infections by members of the genus Proteus. The major factor involved in stone formation is the urease produced by these bacteria, which causes local supersaturation and crystallization of magnesium and calcium phosphates as carbonate apatite [Ca(10)(PO(4))(6).CO(3)] and struvite (MgNH(4)PO(4).6H(2)O), respectively. This effect may also be enhanced by bacterial polysaccharides. Macromolecules of such kind contain negatively charged residues that are able to bind Ca(2+) and Mg(2+), leading to the accumulation of these ions around bacterial cells and acceleration of the crystallization process. The levels of Ca(2+) and Mg(2+) ions bound by whole Proteus cells were measured, as well as the chemical nature of isolated LPS polysaccharides, and the intensity of the in vitro crystallization process was compared in a synthetic urine. The results suggest that the sugar composition of Proteus LPS may either enhance or inhibit the crystallization of struvite and apatite, depending on its chemical structure and ability to bind cations. This points to the increased importance of endotoxin in urinary tract infections. PMID:12748265

  15. Minerals

    MedlinePlus

    ... your body needs in larger amounts. They include calcium, phosphorus, magnesium, sodium, potassium, chloride and sulfur. Your body needs just small amounts of trace minerals. These include iron, manganese, copper, iodine, zinc, cobalt, fluoride and selenium. The best way to ...

  16. Oscillation Laue Analysis (OLA) - A new crystal structure determination method for mineral physics

    NASA Astrophysics Data System (ADS)

    Dera, P.; Downs, R. T.; Liermann, H.; Yang, W.

    2006-12-01

    We present a new approach for collection and interpretation of polychromatic radiation diffraction images, called Oscillation Laue Analysis, which combines capabilities of single crystal X-ray diffraction and X-ray absorption spectroscopy. The method is based on smearing Laue reflections into variable-energy curves by slight oscillation of the crystal during the exposure. The OLA method allows for simple and precise peak energy determination and harmonic overlap deconvolution through measurement of X-ray attenuation coefficient of metal foils inserted into incident beam. The method provides an easy reliable way of determining unit cells of unknown single-crystal phases, yields multiple monochromatic structure factor sets covering wide range of energies, which can be used for Multiple Anomalous Dispersion (MAD) based structure solution or enhancement of contrast between neighboring elements in the periodic table, and allows the routine ab initio solution of unknown structures. The results of our first experiments, performed at sector 16 of the Advanced Photon Source Laboratory, and aimed at determination of the compression mechanism of escolite (Cr2O3) will be presented and discussed in the context of application of the new approach in micromineralogy, characterization of meteoritic samples, and high-pressure mineral physics.

  17. Rare earth elements in minerals of the ALHA77005 shergottite and implications for its parent magma and crystallization history

    NASA Technical Reports Server (NTRS)

    Lundberg, Laura L.; Crozaz, Ghislaine; Mcsween, Harry Y., Jr.

    1990-01-01

    Analyses of mineral REE and selected minor and trace elements were carried out on individual grains of pyroxenes, whitlockite, maskelynite, and olivine of the Antarctic shergottite ALHA77005, and the results are used to interpret its parent magma and crystallization history. The results of mineral compositions and textural observations suggest that ALHA77005 is a cumulate with about half cumulus material (olivine + chromite) and half postcumulus phases. Most of the REEs in ALHA77005 reside in whitlockite whose modal concentration is about 1 percent. Mineral REE data support previous suggestions that plagioclase and whitlockite crystallized late, and that low-Ca pyroxene initiated crystallization before high-Ca pyroxene. The REE patterns for the intercumulus liquid, calculated from distribution coefficients for ALHA77005 pyroxene, plagioclase, and whitlockite, are in very good agreement and are similar to that of Shergotty.

  18. Incorporation of Np(V) and U(VI) in Carbonate and Sulfate Minerals Crystallized from Aqueous Solution

    SciTech Connect

    Balboni, Enrica; Morrison, Jessica M.; Wang, Zheming; Engelhard, Mark H.; Burns, Peter C.

    2015-02-15

    The neptunyl Np(V)O2 + and uranyl U(VI)O2 2+ ions are soluble in groundwater, although their interaction with minerals in the subsurface may impact their mobility. One mechanism for the immobilization of actinyl ions in the subsurface is coprecipitation in low-temperature minerals that form naturally, or that are induced to form as part of a remediation strategy. Important differences in the crystal-chemical behavior of the Np(V) neptunyl and U(VI) uranyl ions suggest their behavior towards incorporation into growing crystals may differ significantly. Using a selection of low temperature minerals synthesized in aqueous systems under ambient conditions, this study examines the factors that impact the structural incorporation of the Np(V) neptunyl and U(VI) uranyl ions in carbonate and sulfate minerals.

  19. Isotopic Zonation Within Sulfate Evaporite Mineral Crystals Reveal Quantitative Paleoenvironment Details

    NASA Astrophysics Data System (ADS)

    Coleman, M.; Rhorssen, M.; Mielke, R. E.

    2008-12-01

    Isotopic variations measured within a single crystal of hydrated magnesium sulfate are greater than 30 permil for delta 2-H, almost 10 permil for δ18O in water of hydration; and greater than 3 permil in sulfate oxygen. These results are interpreted to indicate the relative humidity of the system during evaporation (15 to 20 percent in this test case) and constrain the volume of water involved. The theoretical basis of this system is the isotopic fractionation between the species in solution and those precipitated as evaporite salts. Precipitation preferentially accumulates more of the heavy isotopes of sulfur and oxygen in mineral sulfate, relative to sulfate in solution. During the course of mineral growth this leads to successive depletion of the respective heavier isotopes in the residual brine reflected in a parallel trend in successive precipitates or even in successive zones within a single crystal. The change in isotopic composition at any one time during the process, relative to the initial value, can be described by an isotopic version of the Rayleigh Fractionation equation, depending only on the extent of the completion of the process and the relevant fractionation factor. Evaporation preferentially removes isotopically lighter hydrogen and oxygen leading to successive extents of enrichment in the respective heavier isotopes in the residual water. However, the relative effects on hydrogen and oxygen isotopes differs as function of relative humidity [1]. ALL OF THESE CHANGES ARE PRESERVED IN THE MINERAL ISOTOPE COMPOSITIONS. We precipitated barium sulfate from epsomite or gypsum samples, which was reduced at 1450°C in the presence of graphite and glassy carbon in a Finnigan TC/EA to produce CO for O isotopic analysis in a Finnigan 253 mass spectrometer, while a separate subsample was oxidized to SO2 in a Costech Elemental Analyzer. However, to make progress with this approach we needed to make a large number of measurements of hydration water and so we

  20. Orientation and optical properties of methylene blue crystal for better understanding of interactions with clay mineral surface

    NASA Astrophysics Data System (ADS)

    Milošević, Maja; Logar, Mihovil

    2013-04-01

    The properties of cationic dye Methylene blue (MB) adsorbed on diferent surfaces have been investigated intensively over the years and various models for the orientation of its cations have been proposed (Hang and Brindley, 1970; Bujdak et al., 2003; Li and Zare, 2004; Marr III et al., 1973; Bujdak, 2006).The main objective of this work is to investigate and determine orientation and optical properties of metylene blue crystal upon its crystallization on a glass slate and to use those findings in better understanding of interactions with clay minerals. Cationic dyes have very high affinity for clay surfaces and those interactions are easily detected, therefore these dyes are used to determine several properties of clay surfaces (morphology, layer charge, CEC). For this study, we have selected a group of MB crystal and carried out XRD analysis, polarized absorption spectra measurement (400 - 900 nm) and determination of optical properties (pleochroism, determination of twining and extinction angle) using polarizing microscope. Methylene blue crystals are exhibiting mostly needle like habitus with huge difference in width - length ratio. According to X-ray diffraction it is quite obvious that the y (b) axis is perpendicular to the crystal surface. The x (a) and z (c) axis lie in the crystal plane (010). Crystals exhibit prominent dichroism: from blue (E || elong.) to colorless. In accordance with current interpretation of MB spectra peaks at 647 and 570 nm can be assigned as dimer aggregation and peaks at 475 and 406 nm as higher level of aggregation. All of them exhibit pronounced polarization dependence. The group of peaks at lower energy (700 to 900 nm) do not show significant polarization dependence and they correspond to the J - aggregates. Peak at around 800 nm have been noticed as fluorescence active. In dependence with thickness of the crystals and vibration direction we have observed presence of polysynthetic twinning which can be compared with polysynthetic

  1. Various intensity of Proteus mirabilis-induced crystallization resulting from the changes in the mineral composition of urine.

    PubMed

    Torzewska, Agnieszka; Różalski, Antoni

    2015-01-01

    Infectious urolithiasis is a result of recurrent and chronic urinary tract infections caused by urease-positive bacteria, especially Proteus mirabilis. The main role in the development of this kind of stones is played by bacterial factors such as urease and extracellular polysaccharides, but urinary tract environment also contributes to this process. We used an in vitro model to establish how the changes in the basic minerals concentrations affect the intensity of crystallization which occurs in urine. In each experiment crystallization was induced by an addition of P. mirabilis to artificial urine with a precisely defined chemical composition. Crystallization intensity was determined using the spectrophotometric microdilution method and the chemical composition of formed crystals was established by atomic absorption spectroscopy and colorimetric methods. Increasing the concentration of all crystals forming ions such as Mg(2+), Ca(2+) and phosphate strongly intensified the process of crystallization, whereas reducing the amount of these components below the proper physiological concentration did not affect its intensity. The inhibitory influence of citrate on calcium and magnesium phosphate crystallization and competitive actions of calcium and oxalate ions on struvite crystals formation were not confirmed. In the case of infectious stones the chemical composition of urine plays an important role, which creates a necessity to support the treatment by developing a model of proper diet. PMID:25654361

  2. Effects of fractional crystallization and cumulus processes on mineral composition trends of some lunar and terrestrial rock series

    NASA Technical Reports Server (NTRS)

    Longhi, J.

    1982-01-01

    A plot of Mg of mafic minerals versus An of plagioclase in cumulate rocks from various lunar and terrestrial rock series shows each series to have a distinct curvilinear trend. The slopes of these trends vary from nearly vertical in the case of lunar anorthosites and Mg-norites to nearly horizontal in the case of gabbros from the mid-Atlantic ridge. Calculations based upon known major element partitioning between mafic minerals, plagioclase and subalkaline basaltic liquids indicate that fractional crystallization coupled with cotectic accumulation of mafic minerals and plagioclase will produce mineral composition trends on the Mg versus An diagram with slopes greater than 1 for cases where An is approximately greater than Mg. Furthermore, fractional crystallization of basaltic magmas with alkali concentrations approaching zero will produce near vertical Mg versus An trends. Therefore, the steep slopes of the lunar rock series are consistent with relatively simple fractionation processes. The relatively flat slope of mineral compositions from gabbros collected from the mid-Atlantic ridge at 26 deg N is inconsistent with simple fractionation processes, and calculations show that periodic refilling of a fractionating magma chamber with picritic magma cannot simply explain this flat slope either.

  3. Development of a Single-Crystal Mineral Elasticity Database and Applications to Crustal and Upper Mantle Mineralogy

    NASA Astrophysics Data System (ADS)

    Duffy, T. S.

    2013-12-01

    The single-crystal elastic stiffness tensor fully characterizes the anisotropic elastic response of minerals. An understanding of how such elastic properties vary with pressure, temperature, structure, and composition are needed to interpret seismic data for the Earth. Additionally, elastic moduli are important for understanding many solid-state phenomena including mechanical stability, interatomic interactions, material strength, compressibility, and phase transition mechanisms. A database of single-crystal elastic properties of minerals and related phases is being assembled. This dataset currently incorporates over 400 sets of elastic constant measurements on more than 270 separate phases. In addition to compiling the individual elastic stiffnesses, the database also allows calculation of a variety of additional properties including anisotropy factors, bulk and linear compressibilities, and stability criteria, as well as evaluation of aggregate properties including bounds and averages of bulk, shear, Young's modulus, Poisson's ratio and elastic wave speeds. Extensions of the database to include high pressure and high temperature data as well as theoretical calculations are being planned. Examples of application of this database to geophysical problems will be highlighted. Specific applications to be discussed include: 1) variation of elastic anisotropy with pressure for mantle and crustal minerals; 2) evaluation of elasticity data for pyroxenes revealing major structural and chemical controls on elasticity as well as remaining ambiguities and uncertainties.

  4. Ultrastructure of lamellae, mineral and matrix components of fish otolith twinned aragonite crystals: implications for estimating age in fish.

    PubMed

    Gauldie, R W

    1999-05-01

    Atomic force microscopy (AFM) of the crystalline ultrastructure of otoliths fromPagrus major(Sparidae),Macruronus novaezelandiae(Merlucciidae),Oncorhynchus tshawytscha(Salmonidae),Sebastes alutus(Scorpaenidae), andHoplostethus atlanticus(Trachichthyidae) showed regular deposition of lamellae in the size range 13-490 nm. The orientation of lamellae in the {010} plane was the same as lamellae in crystals of mineral aragonite. Lamellae in mineral aragonite were in the size range 15-45 nm. Lamellae observed in the otolith ofM. novaezelandiaeby transmission electron microscopy showed a range of widths (25-225 nm) similar to lamellae observed by AFM. The observed lamella widths were in the size range that has been described for sub-daily and daily microincrements in otoliths. Observed lamellae widths were also in the size range of alpha-recoil trajectories of(222)Rn and provide a potential diffusion sink correction for the(222)Rn losses in radionuclide method of ageing otoliths. Comparison of the orientations of lamellae to templates based on the Bragg unit cell structure of twinned aragonite indicated that the lamellae resulted from polysynthetic twinning on the {010} aragonite crystal face. Additional cyclic twinning occurred on the {110} face of the aragonite crystal and sometimes led to pseudohexagonal crystals, whose sizes were orders of magnitude larger than lamellae. The organic matrix of the otolith was visible by atomic force and transmission electron microscopy at the nanometer level of resolution, but the organic matrix was confined to the {110} twinning plane of symmetry of the otolith crystal. PMID:18627853

  5. Incorporation of Np(V) and U(VI) in carbonate and sulfate minerals crystallized from aqueous solution

    NASA Astrophysics Data System (ADS)

    Balboni, Enrica; Morrison, Jessica M.; Wang, Zheming; Engelhard, Mark H.; Burns, Peter C.

    2015-02-01

    The neptunyl Np(V)O2+ and uranyl U(VI)O22+ ions are soluble in groundwater, although their interaction with minerals in the subsurface may impact their mobility. One mechanism for the immobilization of actinyl ions in the subsurface is co-precipitation in low-temperature minerals that form naturally, or that are induced to form as part of a remediation strategy. Important differences in the crystal-chemical behavior of the Np(V) neptunyl and U(VI) uranyl ions suggest their behavior towards incorporation into growing crystals may differ significantly. Using a selection of low-temperature minerals synthesized in aqueous systems under ambient conditions, this study examines the factors that impact the structural incorporation of the Np(V) neptunyl and U(VI) uranyl ions in carbonate and sulfate minerals. Calcite (CaCO3), aragonite (CaCO3), gypsum (CaSO4·2H2O), strontianite (SrCO3), cerussite (PbCO3), celestine (SrSO4), and anglesite (PbSO4) were synthesized from aqueous solutions containing either 400-1000 ppm of U(VI) or Np(V) relative to the divalent cation present in the system. The synthetic products were investigated by inductively coupled plasma mass spectrometry, luminescence and time resolved luminescence spectroscopy, X-ray photoelectron spectroscopy, and transmission electron microscopy. Amongst the carbonate minerals, calcite significantly favors Np(V) incorporation over U(VI). U(VI) and Np(V) are incorporated in aragonite and strontianite in similar amounts, whereas cerussite did not incorporate either U(VI) or Np(V) under the synthesis conditions. The sulfate minerals weakly interact with the actinyl ions, relative to the carbonate minerals. Incorporation of U(VI) and Np(V) in celestine was observed at the level of a few tens of ppm; anglesite and gypsum did not incorporate detectable U(VI) or Np(V). Luminescence spectra of the uranyl incorporated in aragonite and strontianite are consistent with a uranyl unit coordinated by three bidentate CO32- groups

  6. The Intrinsically Disordered C-RING Biomineralization Protein, AP7, Creates Protein Phases That Introduce Nanopatterning and Nanoporosities into Mineral Crystals

    PubMed Central

    2015-01-01

    We report an interesting process whereby the formation of nanoparticle assemblies on and nanoporosities within calcite crystals is directed by an intrinsically disordered C-RING mollusk shell nacre protein, AP7. Under mineralization conditions, AP7 forms protein phases that direct the nucleation of ordered calcite nanoparticles via a repetitive protein phase deposition process onto calcite crystals. These organized nanoparticles are separated by gaps or spaces that become incorporated into the forming bulk crystal as nanoporosities. This is an unusual example of organized nanoparticle biosynthesis and mineral modification directed by a C-RING protein phase. PMID:24977921

  7. Single crystal diffraction studies of phase transition of minerals across Fe high-low spin transition at high pressure

    NASA Astrophysics Data System (ADS)

    Merlini, M.; Hanfland, M.

    2011-12-01

    The spin state of Fe in structure of minerals relevant for the lower mantle mineralogy, is known to undergo a high to low spin state change. This phenomena is often coupled to a remarkable volume contraction and from a structural point of view, often is associated to isosymmetrical phase transition. Recent improvements at X-Ray beamlines for diffraction at extreme conditions at synchrotron facilities allow the possibility to perform single crystal diffraction and determine crystal structure of minerals at extreme conditions, including also structural studies across first or second order phase transition. The accurate knowledge of crystal structure and of phase behaviour at high pressure is a very important step in order to: 1-understand the physical properties; 2- have an accurate experimental constraint on numerical simulation. We report here three examples of structure determination by single crystal X-Ray diffraction at extreme conditions concerning phase transition related to Fe spin state change, measured at ID09A beamline (ESRF, France). CaFe2O4 undergoes a spin transition at 50 GPa. XRD before and after indicate the symmetry and crystal structure is the same. The transition is marked by 10 % volume contraction. The use of He as pressure transmitting media strongly reduced strain induced by pressure and let the crystal survive this transition, allowing for the first time direct determination of Fe-O bond length changes related to variation of spin state. The main structural difference between high and low spin structure is simply a collapse of FeO6 polyhedra. FeCO3 has been also investigated, and the results are also compared with already present in literature. FeCO3 undergoes a transition around 45 GPa, with a remarked hysteresis. In the pressure range 20-45 however an anomalous behaviour is noticed, probably related to a different spin interaction due to reduced Fe-Fe distances. Fe1-xS pyrrhotite has been investigated in two different structure (a

  8. The strength of a calcified tissue depends in part on the molecular structure and organization of its constituent mineral crystals in their organic matrix

    NASA Technical Reports Server (NTRS)

    Landis, W. J.

    1995-01-01

    High-voltage electron-microscopic tomographic (3D) studies of the ultrastructural interaction between mineral and organic matrix in a variety of calcified tissues reveal different crystal structural and organizational features in association with their respective organic matrices. In brittle or weak pathologic or ectopic calcifications, including examples of osteogenesis imperfecta, calciphylaxis, calcergy, and dermatomyositis, hydroxyapatite crystals occur in various sizes and shapes and are oriented and aligned with respect to collagen in a manner which is distinct from that found in normal calcified tissues. A model of collagen-mineral interaction is proposed which may account for the observed crystal structures and organization. The results indicate that the ultimate strength, support, and other mechanical properties provided by a calcified tissue are dependent in part upon the molecular structure and arrangement of its constituent mineral crystals within their organic matrix.

  9. The Conterminous United States Mineral Assessment Program; background information to accompany folio of geologic, geophysical, geochemical, mineral-occurrence, mineral-resource potential, and mineral-production maps of the Charlotte 1 degree x 2 degrees Quadrangle, North Carolina and South Carolina

    USGS Publications Warehouse

    Gair, Jacob Eugene; Goldsmith, Richard; Daniels, D.L.; Griffitts, W.R.; DeYoung, J.H.; Lee, M.P.

    1986-01-01

    This Circular and the folio of separately published maps described herein are part of a series of reports compiled under the Conterminous United States Mineral Assessment Program ICUSMAP). The folio on the Charlotte 1 degree ? 2 degree quadrangle, North Carolina and South Carolina, includes (1) a geologic map; (2) four geophysical maps; (3) geochemical maps for metamorphic heavy minerals, copper, lead and artifacts, zinc, gold, tin, beryllium, niobium, tungsten, molybdenum, titanium, cobalt, lithium, barium, antimony-arsenic-bismuth-cadmium, thorium-cerium-monazite, and limonite; (4) mineral-occurrence maps for kyanite-sillimanite-lithium-mica-feldspar-copper-lead-zinc, gold-quartz-barite-fluorite, iron-thorium-tin-niobium, and construction materials-gemstones; (5) mineral-resource potential maps for copper-lead-zinc-combined base metals, gold, tin-tungsten, beryllium-molybdenum-niobium, lithium-kyanite- sillimanitebarite, thorium (monazite)-uranium, and construction materials; and (6) mineral-production maps. The Charlotte quadrangle is mainly within the Piedmont physiographic province and extends from near the Coastal Plain on the southeast into the Blue Ridge province on the northwest for a short distance. Parts of six lithotectonic belts are present--the Blue Ridge, the Inner Piedmont, the Kings Mountain belt, the Charlotte belt, the Carolina slate belt, and the Wadesboro basin. Igneous, metamorphic, and sedimentary rocks are present and range in age from Proterozoic to Mesozoic; alluvial sediments of Quaternary age occur along rivers and larger streams. Rocks of the Blue Ridge include Middle Proterozoic granitoid gneiss intruded by Late Proterozoic granite; Late Proterozoic paragneiss, schist, and other metasedimentary and metavolcaniclastic rocks (Ashe and Grandfather Mountain Formations); Late Proterozoic and Early Cambrian metasedimentary rocks (Chilhowee Group); and Early Cambrian sedimentary rocks (Shady Dolomite). Paleozoic granites intrude the

  10. Dynamics of mineral crystallization at inclusion-garnet interface from precipitated slab-derived fluid phase: first in-situ synchrotron x-ray measurements

    NASA Astrophysics Data System (ADS)

    Malaspina, Nadia; Alvaro, Matteo; Campione, Marcello; Nestola, Fabrizio

    2015-04-01

    Remnants of the fluid phase at ultrahigh pressure (UHP) in subduction environments may be preserved as primary multiphase inclusions in UHP minerals. These inclusions are frequently hosted by minerals stable at mantle depths, such as garnet, and show the same textural features as fluid inclusions. The mineral infillings of the solid multiphase inclusions are generally assumed to have crystallized by precipitation from the solute load of dense supercritical fluids equilibrating with the host rock. Notwithstanding the validity of this assumption, the mode of crystallization of daughter minerals during precipitation within the inclusion and/or the mechanism of interaction between the fluid at supercritical conditions and the host mineral are still poorly understood from a crystallographic point of view. A case study is represented by garnet orthopyroxenites from the Maowu Ultramafic Complex (China) deriving from harzburgite precursors metasomatised at ~ 4 GPa, 750 °C by a silica- and incompatible trace element-rich fluid phase. This metasomatism produced poikilitic orthopyroxene and inclusion-rich garnet porphyroblasts. Solid multiphase primary inclusions in garnet display a size within a few tens of micrometers and negative crystal shapes. Infilling minerals (spinel: 10-20 vol.%; amphibole, chlorite, talc, mica: 80- 90 vol.%) occur with constant volume ratios and derive from trapped solute-rich aqueous fluids. To constrain the possible mode of precipitation of daughter minerals, we performed for the first time a single-crystal X-ray diffraction experiment by means of Synchrotron Radiation at DLS-Diamond Light Source. In combination with electron probe microanalyses, this measurement allowed the unique identification of each mineral phase and their reciprocal orientations. We demonstrated the epitaxial relationship between spinel and garnet and between some hydrous minerals. Epitaxy drives a first-stage nucleation of spinel under near-to-equilibrium conditions

  11. Crystal and molecular structure and spectroscopic behavior of isotypic synthetic analogs of the oxalate minerals stepanovite and zhemchuzhnikovite

    NASA Astrophysics Data System (ADS)

    Piro, Oscar E.; Echeverría, Gustavo A.; González-Baró, Ana C.; Baran, Enrique J.

    2016-04-01

    The crystal structure of synthetic stepanovite, Na[Mg(H2O)6][Fe(C2O4)3]·3H2O, and zhemchuzhnikovite, Na[Mg(H2O)6][Al0.55Fe0.45(C2O4)3]·3H2O, has been determined by single-crystal X-ray diffraction methods. The compounds are isotypic to each other and to the previously reported Na[Mg(H2O)6][M(C2O4)3]·3H2O (M: Cr, Al). They crystallize in the trigonal P3 c1 space group with Z = 6 molecules per unit cell and (hexagonal axes) a = 17.0483(4), c = 12.4218(4) Å for the iron compound, and a = 16.8852(5), c = 12.5368(5) Å for the Al/Fe solid solution. Comparison of our crystallographic results with previous X-ray diffraction and chemical data of type stepanovite and zhemchuzhnikovite minerals provides compelling evidence that these natural materials possess the same crystal and molecular structure as their synthetic counterparts. It is shown that the originally reported unit cell for stepanovite represents a pronounced sub-cell and that the correct unit cell and space group are based on weak superstructure reflections. The infrared and Raman spectra of both synthetic analogs were also recorded and are briefly discussed.

  12. Phase transitions of aqueous atmospheric particles: Crystallization of ammonium salts promoted by oxide mineral constituents

    NASA Astrophysics Data System (ADS)

    Han, Jeong-Ho

    2001-09-01

    Knowledge of the hygroscopic response of aerosols is a fundamental factor necessary for the accurate quantitative modeling of visibility degradation, global warming, PM-10 health issues, cloud microphysics, and the oxidizing capacity of the troposphere. At the present time, however, our current understanding of phase transitions is insufficient to develop accurate quantitative models. The discrepancy between current atmospheric models and field measurements originates mainly from a lack of understanding of the efflorescence of real atmospheric particles. While there have been many studies on the homogeneous nucleation of the soluble organic, inorganic, or multi-component materials, many recent in situ field measurements with single-particle mass spectrometry reveal that the individual particles in the troposphere are primarily composed of more than one component. One of the common mixed component particle types contains both water- soluble and insoluble components. Through atmospheric processes, the soluble component can be expected to form a coating around the insoluble constituents. This type of atmospheric particles is very important because the insoluble constituent can play a role as a template for the crystallization of the soluble components by heterogeneous nucleation. In the atmosphere, the most prevalent insoluble constituents are mineral dusts, which have their origin from Saharan and Gobbi deserts. The existence of these coated particles has been supported by several field measurements as well as model studies. Therefore, it becomes imperative to simulate more realistic atmospheric particles for more exact (or realistic) understanding the phase transition of the ambient aerosol particles in the real world. In this context, a series of studies has been completed to solve the aforementioned problems in the phase transition study and to better understand the heterogeneous nucleation of these internally mixed particles. An in-line tube furnace has been

  13. Vein Controlled Index Mineral Crystal Size Distribution in Barrow's Metamorphic Zones, Glen Esk, Scotland

    NASA Astrophysics Data System (ADS)

    Lewerentz, A.; Skelton, A.; Linde, J. K.; Nilsson, J.; Möller, C.; Crill, P. M.; Spicuzza, M. J.

    2015-12-01

    The concept of index mineral based metamorphic zones was first introduced by George Barrow a little more than 100 years ago, and the Barrovian metamorphic zones are still today used as framework by metamorphic petrologists. Today the importance of metamorphic fluids for driving metamorphic reactions is widely recognised. Even so, a general view is that Barrovian metamorphism is solely controlled by pressure, temperature, and protolith composition. This study aims to establish if and how fluids control index mineral formation and distribution during Barrovian metamorphism. To do so, we use samples from Barrow's own type locality in Glen Esk, Southeast Scottish Highlands, and study possible relationships between veining and index mineral distribution. In addition to petrographic and textural observations and analyses, we also use whole rock chemistry, mineral chemistry, and oxygen isotope analyses. At low grade, in the chlorite zone and most of the biotite zone, no correlation between veining and index mineral distribution is seen. At higher grade, the index mineral abundance is shown to decrease away from veins in the garnet and staurolite zones. Pseudosection analysis show larger garnet stability fields in vein-adjacent rock. In addition, quartz abundance and oxygen isotope ratios of quartz coincidentally decrease, which we interpret as evidence for fluid-rock interaction. The kyanite zone shows a fairly homogenous kyanite distribution, but also indications of extensive fluid-rock interaction, such as high vein density and oxygen isotope ratios in equilibrium with the fluid. Based on our observations and the geochemical datasets, we conclude that fluid played a major role in the stabilisation and distribution of the Barrovian index minerals in Glen Esk, and that the fluid control was larger at higher metamorphic grades.

  14. Deducing growth mechanisms for minerals from the shapes of crystal size distributions

    USGS Publications Warehouse

    Eberl, D.D.; Drits, V.A.; Srodon, J.

    1998-01-01

    Crystal size distributions (CSDs) of natural and synthetic samples are observed to have several distinct and different shapes. We have simulated these CSDs using three simple equations: the Law of Proportionate Effect (LPE), a mass balance equation, and equations for Ostwald ripening. The following crystal growth mechanisms are simulated using these equations and their modifications: (1) continuous nucleation and growth in an open system, during which crystals nucleate at either a constant, decaying, or accelerating nucleation rate, and then grow according to the LPE; (2) surface-controlled growth in an open system, during which crystals grow with an essentially unlimited supply of nutrients according to the LPE; (3) supply-controlled growth in an open system, during which crystals grow with a specified, limited supply of nutrients according to the LPE; (4) supply- or surface-controlled Ostwald ripening in a closed system, during which the relative rate of crystal dissolution and growth is controlled by differences in specific surface area and by diffusion rate; and (5) supply-controlled random ripening in a closed system, during which the rate of crystal dissolution and growth is random with respect to specific surface area. Each of these mechanisms affects the shapes of CSDs. For example, mechanism (1) above with a constant nucleation rate yields asymptotically-shaped CSDs for which the variance of the natural logarithms of the crystal sizes (??2) increases exponentially with the mean of the natural logarithms of the sizes (??). Mechanism (2) yields lognormally-shaped CSDs, for which ??2 increases linearly with ??, whereas mechanisms (3) and (5) do not change the shapes of CSDs, with ??2 remaining constant with increasing ??. During supply-controlled Ostwald ripening (4), initial lognormally-shaped CSDs become more symmetric, with ??2 decreasing with increasing ??. Thus, crystal growth mechanisms often can be deduced by noting trends in ?? versus ??2 of CSDs for

  15. Using the potential of accessory minerals: detailed reconstruction of emplacement and crystallization sequence in the Southern Adamello Batholith, N. Italy

    NASA Astrophysics Data System (ADS)

    Broderick, C. A.; Schaltegger, U.; Frick, D.; Guenther, D.; Brack, P.

    2011-12-01

    Recent advances in U-Pb zircon geochronology have revealed the complexities of pluton construction, by multiple injections on 10-100 ka to Ma timescales (Michel et al., 2008, Schaltegger et al., 2009). Using high precision U-Pb dating we are potentially able to describe the duration and evolution of magmatic systems, their crystallization and emplacement within the crust. The potential exists to better understand these processes by detailed study of accessory minerals. The trace element and isotopic characteristics of accessory minerals makes them important information carriers for tracking changes in a magma through time. High precision U-Pb dating, using CA-ID-TIMS and employing the ET2535 tracer solution for <0.1% precision and accuracy on 206Pb/238U zircon and titanite dates, and trace element analyses of zircon and titanite, combined with Hf isotope analysis of zircon are presented for the investigation of a complex magmatic system. This study focuses on the Val Fredda Complex (VFC) in the southern tip of the 43 to 32 Ma Adamello batholith, N. Italy. The VFC displays complex relationships among mafic melts that were injected into solidifying felsic magmas. The mafic units crystallized potential autocrystic zircons over a duration of 100 ka, with the majority of zircons co-crystallizing with titanite. The TIMS-TEA method (Schoene et al., 2010) allows us to analyze trace elements on the same volume of zircon/titanite used for U-Pb dating. Mafic zircon and titanite trace elements (e.g., Eu/Eu* and Sr) suggest that these accessory minerals crystallized prior to plagioclase fractionation. Based on experiments (Ulmer et al., 1983) and the trace element data from this study, we suggest that the mafic zircons and titanites do not represent in situ crystallization and therefore are more likely antecrystic. Data from the VFC felsic units show more complex zircon populations, including xenocrystic, antecrystic and autocrystic zircons. These felsic units have apparent

  16. Iron-rich schüllerite from Kahlenberg (Eifel, Germany): Crystal structure and relation to lamprophyllite-group minerals

    NASA Astrophysics Data System (ADS)

    Rastsvetaeva, R. K.; Aksenov, S. M.; Chukanov, N. V.; Lykova, I. S.; Verin, I. A.

    2014-11-01

    A single-crystal sample of iron-rich schüllerite found at the Kahlenberg quarry in the Eifel paleovolcanic field (Germany) was studied by X-ray diffraction. The triclinic unit-cell parameters are as follows: a = 5.4061(1) Å, b = 7.0416(6) Å, c = 10.2077(7) Å, α = 99.86(1)°, β = 97.8(1)°, and γ = 89.98(1)°. The structure was solved by direct methods in sp. gr. P1 and refined to the R factor of 7.9% based on 4321 | F| > 6σ( F). The idealized formula is Ba2Na(Ca,Mn)(Fe2+,Fe3+)MgTi2[Si2O7]2O2(O,F)F. The new mineral differs from schüllerite by a lower sodium content and higher iron and calcium contents and is characterized by some distinguishing structural features. The dependence of the topology of layered HOH modules on the sodium content in schüllerite and lamprophyllite-group minerals and the character of regular intergrowths of these minerals are discussed.

  17. Rocks and Minerals.

    ERIC Educational Resources Information Center

    Naturescope, 1987

    1987-01-01

    Provides background information on rocks and minerals, including the unique characteristics of each. Teaching activities on rock-hunting and identification, mineral configurations, mystery minerals, and growing crystals are provided. Reproducible worksheets are included for two of the activities. (TW)

  18. Crystal growth of a layered silicate clay mineral as revealed by atomic force microscopy

    SciTech Connect

    Carrado, K.A.; Song, Kang; Zajac, G.W.

    1997-12-31

    Non-contact atomic force microscopy, commonly referred to as {open_quotes}tapping mode{close_quotes} AFM, has been used to scan primarily the morphological features of growing hectorite clay crystallites synthesized in the presence of organo-ammonium cations. The use of such cations allows larger crystals to form in this system, making study by AFM feasible. This is the first time that actual temporal {open_quotes}snapshots{close_quotes} of a clay`s nucleation and crystallization processes have been presented. The observed view does not support the perhaps predicted scene of small crystallites slowly ripening into larger and larger plates. Instead, larger and larger aggregates appear to coalesce from a larger number of small crystallites that are closely associated in globular networks similar in appearance to {open_quotes}strings of pearls{close_quotes} at the initial stages of crystallization.

  19. Description and crystal structure of nyholmite, a new mineral related to hureaulite, from Broken Hill, New South Wales, Australia

    SciTech Connect

    Elliott, P.; Turner, P.; Jensen, P.; Kolitsch, U.; Pring, A.

    2010-08-12

    Nyholmite, Cd{sub 3}Zn{sub 2}(AsO{sub 3}OH){sub 2}(AsO{sub 4}){sub 2} {center_dot} 4H{sub 2}O, from the Block 14 Opencut, Broken Hill, New South Wales, Australia, is a new Cd-Zn arsenate species, isostructural with the minerals of the hureaulite group. The mineral occurs in a quartz-garnet-arsenopyrite matrix as white globules, tufted aggregates of fibrous crystals and radiating hemispheres of thin, colourless, bladed crystals. Associated minerals are goldquarryite, lavendulan-sampleite, scorodite-strengite and gypsum. Individual crystals are up to 0.2 mm in length and 0.05 mm across. The mineral is transparent to translucent with a vitreous lustre. It is brittle with an uneven fracture and a white streak. The Mohs hardness is 3-3.5 and the calculated density is 4.23 g cm{sup -3} for the empirical formula. Electron microprobe analyses yielded CdO 34.58, ZnO 9.72, MnO 3.59, CuO 3.39, Al{sub 2}O{sub 3} 0.20, CaO 0.16, PbO 0.37, As{sub 2}O{sub 5} 34.55, P{sub 2}O{sub 5} 6.29 totalling 92.85 wt.%. The empirical formula, based on 20 oxygen atoms, is Ca{sub 0.03}Pb{sub 0.02} Cd{sub 2.80}Al{sub 0.04}Zn{sub 1.24}-Cu{sub 0.44}Mn{sub 0.53}[(AsO{sub 4}){sub 3.13}(PO{sub 4}){sub 0.92}]{Sigma}{sub 4.05}H{sub 1.91} {center_dot} 3.79H{sub 2}O. Nyholmite is monoclinic, C2/c, a = 18.062(4) {angstrom}, b = 9.341(2) {angstrom}, c = 9.844(2) {angstrom}, {beta} = 96.17(3){sup o}, V = 1651.2(6) {angstrom}{sup 3} (single-crystal data, at 123 K). The six strongest lines in the X-ray powder diffraction pattern are [d({angstrom}),I,(hkl)]: 8.985,30,(200); 8.283, 85,(110); 6.169,25,(111); 4.878,25,(002); 3.234,100,(222, 420); 3.079,65,(222, 511); 2.976,45,(113). The crystal structure was solved by Patterson methods and refined using 2045 observed reflections to R1(F) = 3.73%. The structure is characterized by a kinked, five-membered chain of edge-sharing M{phi}{sub 6} ({phi} = unspecified anion) octahedra, or pentamer, that extends in the a direction. The pentamers link by sharing corners to

  20. Crystal chemical correlations between the mid and near-infrared in carbonate minerals

    NASA Astrophysics Data System (ADS)

    Hopkinson, Laurence; Rutt, Ken J.

    2016-06-01

    Near-infrared (NIR) spectra of carbonates have proved important in many disciplines including planetary exploration. Classically bands in the 4000-6000 cm- 1 (2.5-1.67 μm) region are assigned to [CO32-] internal mode combinations and overtones. However band assignments remain equivocal. This study examines three prominent bands ((ca 4505 cm- 1 (2.219 μm), 4900 cm- 1 (2.041 μm) and 5145 cm- 1 (1.944 μm)) from powdered calcite and aragonite group minerals. Results indicate that the bands originate from anharmonic coupling of degenerate internal mode(s) with external (lattice) modes. On this basis it is suggested that NIR data may provide an untapped source of detailed information on lattice mode frequencies and information on the type(s) of the environmental cation(s) in carbonate minerals.

  1. Crystal chemical correlations between the mid and near-infrared in carbonate minerals.

    PubMed

    Hopkinson, Laurence; Rutt, Ken J

    2016-06-01

    Near-infrared (NIR) spectra of carbonates have proved important in many disciplines including planetary exploration. Classically bands in the 4000-6000cm(-1) (2.5-1.67μm) region are assigned to [CO3(2-)] internal mode combinations and overtones. However band assignments remain equivocal. This study examines three prominent bands ((ca 4505cm(-1) (2.219μm), 4900cm(-1) (2.041μm) and 5145cm(-1) (1.944μm)) from powdered calcite and aragonite group minerals. Results indicate that the bands originate from anharmonic coupling of degenerate internal mode(s) with external (lattice) modes. On this basis it is suggested that NIR data may provide an untapped source of detailed information on lattice mode frequencies and information on the type(s) of the environmental cation(s) in carbonate minerals. PMID:26994319

  2. Crystal-field-driven redox reactions: How common minerals split H2O and CO2 into reduced H2 and C plus oxygen

    NASA Technical Reports Server (NTRS)

    Freund, F.; Batllo, F.; Leroy, R. C.; Lersky, S.; Masuda, M. M.; Chang, S.

    1991-01-01

    It is difficult to prove the presence of molecular H2 and reduced C in minerals containing dissolved H2 and CO2. A technique was developed which unambiguously shows that minerals grown in viciously reducing environments contain peroxy in their crystal structures. The peroxy represent interstitial oxygen atoms left behind when the solute H2O and/or CO2 split off H2 and C as a result of internal redox reactions, driven by the crystal field. The observation of peroxy affirms the presence of H2 and reduced C. It shows that the solid state is indeed an unusual reaction medium.

  3. A new mineral species rossovskyite, (Fe3+,Ta)(Nb,Ti)O4: crystal chemistry and physical properties

    NASA Astrophysics Data System (ADS)

    Konovalenko, Sergey I.; Ananyev, Sergey A.; Chukanov, Nikita V.; Rastsvetaeva, Ramiza K.; Aksenov, Sergey M.; Baeva, Anna A.; Gainov, Ramil R.; Vagizov, Farit G.; Lopatin, Oleg N.; Nebera, Tatiana S.

    2015-11-01

    A new mineral rossovskyite named after L.N. Rossovsky was discovered in granite pegmatites of the Bulgut occurrence, Altai Mts., Western Mongolia. Associated minerals are microcline, muscovite, quartz, albite, garnet of the almandine-spessartine series, beryl, apatite, triplite, zircon, pyrite, yttrobetafite-(Y) and schorl. Rossovskyite forms flattened anhedral grains up to 6 × 6 × 2 cm. The color of the mineral is black, and the streak is black as well. The luster is semi-metallic, dull. Mohs hardness is 6. No cleavage or parting is observed. Rossovskyite is brittle, with uneven fracture. The density measured by the hydrostatic weighing method is 6.06 g/cm2, and the density calculated from the empirical formula is 6.302 g/cm3. Rossovskyite is biaxial, and the color in reflection is gray to dark gray. The IR spectrum contains strong band at 567 cm-1 (with shoulders at 500 and 600 cm-1) corresponding to cation-oxygen stretching vibrations and weak bands at 1093 and 1185 cm-1 assigned as overtones. The reflection spectrum in visible range is obtained. According to the Mössbauer spectrum, the ratio Fe2+:Fe3+ is 35.6:64.4. The chemical composition is as follows (electron microprobe, Fe apportioned between FeO and Fe2O3 based on Mössbauer data, wt%): MnO 1.68, FeO 5.92, Fe2O3 14.66, TiO2 7.69, Nb2O5 26.59, Ta2O5 37.51, WO3 5.61, total 99.66. The empirical formula calculated on four O atoms is: {{Mn}}_{0.06}^{2 + } {{Fe}}_{0.21}^{2 + } {{Fe}}_{0.47}^{3 + } Ti0.25Nb0.51Ta0.43W0.06O4. The crystal structure was determined using single-crystal X-ray diffraction data. The new mineral is monoclinic, space group P2/ c, a = 4.668(1), b = 5.659(1), c = 5.061(1) Å, β = 90.21(1)º; V = 133.70(4) Å3, Z = 2. Topologically, the structure of rossovskyite is analogous to that of wolframite-group minerals. The crystal-chemical formula of rossovskyite is [(Fe3+, Fe2+, Mn)0.57Ta0.32Nb0.11][Nb0.40Ti0.25Fe0.18Ta0.11W0.06]O4. The strongest lines of the powder X-ray diffraction pattern

  4. Structure-activity relationships of mineral dusts as heterogeneous nuclei for ammonium sulfate crystallization from supersaturated aqueous solutions.

    PubMed

    Martin, S T; Schlenker, J; Chelf, J H; Duckworth, O W

    2001-04-15

    Mineral inclusions, present in aqueous atmospheric salt droplets, regulate crystallization when relative humidity decreases by providing a surface for heterogeneous nucleation and thus reducing the critical supersaturation. Although laboratory studies have quantified these processes to some extent, the diverse atmospheric mineralogy presents more chemical systems than practically feasible for direct study. Structure--activity relationships are necessary. To that end, in the present work the interactions of ammonium sulfate with corundum, hematite, mullite, rutile, anatase, and baddeleyite were studied by diffuse reflectance fourier transform infrared spectroscopy (DRIFTS) and by epitaxial modeling. The spectroscopic results show that shifts in sulfate peak positions due to chemisorption are not a correlative indicator of the efficacy of heterogeneous nucleation. In contrast, epitaxial modeling results of unreconstructed surfaces explain the sequence of critical supersaturations for constant particle size. If validated by further work, this computer modeling method would provide an important structure--activity tool for the estimation of heterogeneous nucleation properties of the atmospheric mineralogy. PMID:11329712

  5. The effect of crystal plasticity and mineral stability on the rheological properties of magma during spine extrusion at Unzen, Japan

    NASA Astrophysics Data System (ADS)

    Wallace, Paul A.; Kendrick, Jackie E.; Lavallée, Yan; Ashworth, James D.; Mariani, Elisabetta; von Aulock, Felix W.; Coats, Rebecca; Miwa, Takahiro

    2016-04-01

    phenocrysts and microlites, with biotite displaying the greatest evidence of strain accommodation. This permanent strain is induced when the shear stress exceeds a critical point on an orientated lattice plane, resulting in a misorientation of the internal lattice. Crystal-plastic behaviour may thus act as a strain marker for the viscous-brittle transition during ascent. In the highly sheared zone, the rims of both hydrous minerals (hornblende and biotite) and plagioclase show a reaction with the melt suggesting disequilibrium conditions - a feature not as evident in the undeformed magmatic core of the spine. The narrow localisation of the disequilibrium textures suggest that the increased effects of gas flow in the permeable shear zone and/or thermal input due to strain localisation may be contributing factors affecting mineral stability during magma transport. These deformation microstructures that occur in the shallow conduit, especially during ascent of highly viscous magma, can lead to permeability anisotropy which can significantly alter degassing efficiency and control the explosivity of an eruption. For this reason a thorough petrological/rheological understanding of these deformation processes is vital in constraining the complexities associated with on-going eruptions and shifts from effusive to explosive activity.

  6. Crystal Chemistry of Cement-Clinker Minerals and Melt Differentiation Reaction of Interstitial Melt

    NASA Astrophysics Data System (ADS)

    Fukuda, Koichiro

    Microtextures of belite induced by polymorphic phase transitions and a remelting reaction have been reviewed, together with the melt differentiation reaction of interstitial melt. In the α-to-α'H phase transition, the α'H-phase nucleates as lamellae within the parent α-phase so as to realize a good lattice matching across the interface. The remelting reaction, in which the α-phase belite decomposes into a liquid and the α'H-phase during cooling, is necessarily preceded by the α-to-α'H phase transition. The lamella boundaries provide heterogeneous nucleation sites for the exsolving liquid. A variety of microtextures results depending on the surface tension between belite lamellae and exsolved liquid as well as on the cooling rate. As the simultaneous crystallization of zoned ferrite and belite proceeds during the cooling process of clinkers, the coexisting melt progressively increases the Al2O3/Fe2O3 ratio. After the termination of the ferrite crystallization, the aluminete and belite crystallize out of the differentiated melt.

  7. Filaments in Carbonaceous Meteorites: Mineral Crystals, Modern Bio-Contaminants or Indigenous Microfossils of Trichomic Prokaryotes?

    NASA Technical Reports Server (NTRS)

    Hoover, Richard B.; Borisyak, A. A.

    2011-01-01

    Environmental (ESEM) and Field Emission Scanning Electron Microscopy (FESEM) investigations have resulted in the detection of a large number of complex filaments in a variety of carbonaceous meteorites. Many of the filaments were observed to be clearly embedded the rock matrix of freshly fractured interior surfaces of the meteorites. The high resolution images obtained combined with tilt and rotation of the stage provide 3-dimensional morphological and morphometric data for the filaments. Calibrated Energy Dispersive X-ray Spectroscopy (EDS) and 2-D elemental X-ray maps have provided information on the chemical compositions of the filaments and the minerals of the associated meteorite rock matrix. These observations are used to evaluate diverse hypotheses regarding the possible abiotic or biogenic nature of the filaments found embedded in these meteorites.

  8. Structural Development of Mercaptophenol Self-Assembled Monolayers And the Overlying Mineral Phase During Templated CaCo(3) Crystallization From a Transient Amorphous Film

    SciTech Connect

    Lee, J.R.I.; Han, T.Y.-J.; Willey, T.M.; Wang, D.; Meulenberg, R.W.; Nilsson, J.; Dove, P.M.; Terminello, L.J.; Buuren, T.van; Yoreo, J.J.De

    2009-06-01

    Formation of biomineral structures is increasingly attributed to directed growth of a mineral phase from an amorphous precursor on an organic matrix. While many in vitro studies have used calcite formation on organothiol self-assembled monolayers (SAMs) as a model system to investigate this process, they have generally focused on the stability of amorphous calcium carbonate (ACC) or maximizing control over the order of the final mineral phase. Little is known about the early stages of mineral formation, particularly the structural evolution of the SAM and mineral. Here we use near-edge X-ray absorption spectroscopy (NEXAFS), photoemission spectroscopy (PES), X-ray diffraction (XRD), and scanning electron microscopy (SEM) to address this gap in knowledge by examining the changes in order and bonding of mercaptophenol (MP) SAMs on Au(111) during the initial stages of mineral formation as well as the mechanism of ACC to calcite transformation during template-directed crystallization. We demonstrate that formation of ACC on the MP SAMs brings about a profound change in the morphology of the monolayers: although the as-prepared MP SAMs are composed of monomers with well-defined orientations, precipitation of the amorphous mineral phase results in substantial structural disorder within the monolayers. Significantly, a preferential face of nucleation is observed for crystallization of calcite from ACC on the SAM surfaces despite this static disorder.

  9. Mineral chemical compositions of late Cretaceous volcanic rocks in the Giresun area, NE Turkey: Implications for the crystallization conditions

    NASA Astrophysics Data System (ADS)

    Oǧuz, Simge; Aydin, Faruk; Uysal, İbrahim; Şen, Cüneyt

    2016-04-01

    This contribution contains phenocryst assemblages and mineral chemical data of late Cretaceous volcanic (LCV) rocks from the south of Görele and Tirebolu areas (Giresun, NE Turkey) in order to investigate their crystallization conditions. The LCV rocks in the study area occur in two different periods (Coniasiyen-Early Santonian and Early-Middle Campanian), which generally consist of alternation of mafic-intermediate (basaltic to andesitic) and felsic rock series (dacitic and rhyolitic) within each period. The basaltic and andesitic rocks in both periods generally exhibit porphyritic to hyalo-microlitic porphyritic texture, and contain phenocrysts of plagioclase and pyroxene, whereas the dacitic and rhyolitic rocks of the volcanic sequence usually show a vitrophyric texture with predominant plagioclase, K-feldspar, quartz and lesser amphibole-biotite phenocrysts. Zoned plagioclase crystals of the mafic and felsic rocks in different volcanic periods are basically different in composition. The compositions of plagioclase in the first-stage mafic rocks range from An52 to An78 whereas those of plagioclase from the first-stage felsic rocks have lower An content varying from An38 to An50. Rim to core profile for the zoned plagioclase of the first-stage mafic rocks show quite abrupt and notable compositional variations whereas that of the first-stage felsic rocks show slight compositional variation, although some of the grains may display reverse zoning. On the other hand, although no zoned plagioclase phenocryst observed in the second-stage mafic rocks, the compositions of microlitic plagioclase show wide range of compositional variation (An45‑80). The compositions of zoned plagioclase in the second-stage felsic rocks are more calcic (An65‑81) than those of the first-stage felsic rocks, and their rim to core profile display considerable oscillatory zoning. The compositions of pyroxenes in the first- and second-stage mafic-intermediate rocks vary over a wide range

  10. Mineral chemistry, crystallization conditions and geodynamic implications of the Oligo-Miocene granitoids in the Biga Peninsula, Northwest Turkey

    NASA Astrophysics Data System (ADS)

    Aysal, Namık

    2015-06-01

    Widespread plutonic rocks in NW Turkey occur within the southward-younging and overlapping magmatic belts across the Aegean region. Post-collisional magmatism is represented by a series of granitoidic intrusions and volcanic successions. K-Ar and U-Pb LA-ICP-MS zircon dating of the Kazdağ and Yenice plutons yielded ages between 20.5 ± 0.5 Ma and 27.89 ± 0.17 Ma (Late Oligocene-Early Miocene). The granitoid samples are high-K calc-alkaline and metaluminous to slightly peraluminous. The 87Sr/86Sr values for the granitoids, enclaves and leucocratic rocks range between 0.705168 and 0.708357. The initial 143Nd/144Nd ratios calculated for the crystallization ages of ca. 23-27 Ma are between 0.512425 and 0.512614, and the εNd values vary from -3.5 to 0.2. The Nd TDM model ages range between 0.73 and 1.13 Ga. These samples are enriched in LILEs and LREE and depleted in HFSEs with negative Eu anomalies, indicating that the melts were derived from an enriched lithospheric mantle modified by subducted slab-derived melts. Energy constrained-assimilation and fractional crystallization (EC-AFC) modelling indicates that fractional crystallization and crustal assimilation modified the parent magma's composition during its residence in the upper crust. The mineral chemistry of amphiboles, pyroxenes, biotites and feldspars is used to constrain the pressure (P), temperature (T), oxygen fugacity (logƒO2) and water contents (H2Omelt) during the crystallization of the magmas in the studied granitoids. The clinopyroxene temperatures are in the range of 823-910 ± 45 °C. The amphibole temperatures for the studied plutonic rocks are in the range of 707-926 °C (mean = 798 ± 45 °C), and the crystallization depths are estimated to be in the interval of 1.02-10.2 km. The NW Anatolian plutonic rocks can be considered to have been equilibrated at the oxygen fugacities of calcic amphiboles (logƒO2) between -8.99 and -13.96 bars (mean = -12.11 bar) and H2Omelt contents between 1.63% and

  11. Crystallizing the function of the magnetosome membrane mineralization protein Mms6.

    PubMed

    Staniland, Sarah S; Rawlings, Andrea E

    2016-06-15

    The literature on the magnetosome membrane (MM) protein, magnetosome membrane specific6 (Mms6), is reviewed. Mms6 is native to magnetotactic bacteria (MTB). These bacteria take up iron from solution and biomineralize magnetite nanoparticles within organelles called magnetosomes. Mms6 is a small protein embedded on the interior of the MM and was discovered tightly associated with the formed mineral. It has been the subject of intensive research as it is seen to control the formation of particles both in vivo and in vitro Here, we compile, review and discuss the research detailing Mms6's activity within the cell and in a range of chemical in vitro methods where Mms6 has a marked effect on the composition, size and distribution of synthetic particles, with approximately 21 nm in size for solution precipitations and approximately 90 nm for those formed on surfaces. Furthermore, we review and discuss recent work detailing the structure and function of Mms6. From the evidence, we propose a mechanism for its function as a specific magnetite nucleation protein and summaries the key features for this action: namely, self-assembly to display a charged surface for specific iron binding, with the curvature of the surfaces determining the particle size. We suggest these may aid design of biomimetic additives for future green nanoparticle production. PMID:27284056

  12. Crystallizing the function of the magnetosome membrane mineralization protein Mms6

    PubMed Central

    Staniland, Sarah S.; Rawlings, Andrea E.

    2016-01-01

    The literature on the magnetosome membrane (MM) protein, magnetosome membrane specific6 (Mms6), is reviewed. Mms6 is native to magnetotactic bacteria (MTB). These bacteria take up iron from solution and biomineralize magnetite nanoparticles within organelles called magnetosomes. Mms6 is a small protein embedded on the interior of the MM and was discovered tightly associated with the formed mineral. It has been the subject of intensive research as it is seen to control the formation of particles both in vivo and in vitro. Here, we compile, review and discuss the research detailing Mms6’s activity within the cell and in a range of chemical in vitro methods where Mms6 has a marked effect on the composition, size and distribution of synthetic particles, with approximately 21 nm in size for solution precipitations and approximately 90 nm for those formed on surfaces. Furthermore, we review and discuss recent work detailing the structure and function of Mms6. From the evidence, we propose a mechanism for its function as a specific magnetite nucleation protein and summaries the key features for this action: namely, self-assembly to display a charged surface for specific iron binding, with the curvature of the surfaces determining the particle size. We suggest these may aid design of biomimetic additives for future green nanoparticle production. PMID:27284056

  13. The Midcontinent Strategic and Critical Minerals Project; summary and background information to accompany folio of maps of the northern Midcontinent area, latitude 36-46 degrees N. and longitude 88-100 degrees W.

    USGS Publications Warehouse

    Pratt, Walden P.

    1995-01-01

    The Midcontinent Strategic and Critical Minerals Project was a broad investigation into the mineral-resource potential of the northern Midcontinent region of the United States. One product of the project is a folio of 10 sets of maps and one set of cross sections, all at a scale of 1:1,000,000, showing several subsurface geologic aspects of the region. This report summarizes the history of the multi-state cooperative project and the general content of the 11 map publications, and gives a visual sense of the scope and content of the folio through page-size samples of each of the map products.

  14. Boundaries of intergrowths between mineral individuals: A zone of secondary mineral formation in aggregates

    NASA Astrophysics Data System (ADS)

    Brodskaya, R. L.; Bil'Skaya, I. V.; Lyakhnitskaya, V. D.; Markovsky, B. A.; Sidorov, E. G.

    2007-12-01

    Intergrowth boundaries between mineral individuals in dunite of the Gal’moenan massif in Koryakia was studied in terms of crystal morphology, crystal optics, and ontogenesis. The results obtained allowed us to trace the staged formation of olivine and chromite and four generations of these minerals. Micro-and nanotopography of boundary surfaces between intergrown mineral individuals of different generations was examined with optic, electron, and atomic force microscopes. The boundaries between mineral individuals of different generations are distinguished by their microsculpture for both olivine and chromite grains. Both minerals demonstrate a compositional trend toward refinement from older to younger generations. The decrease in the iron mole fraction in olivine and chromite is accompanied by the crystallization of magnetite along weakened zones in olivine of the first generation and as outer rims around the chromite grains of the second generation observable under optic and electronic microscopes. The subsequent refinement of chromite results in the release of PGE from its lattice, as established by atomic power microscopy. The newly formed PGM are localized at the boundaries between mineral individuals and, thus, mark a special stage in the ontogenetic evolution of mineral aggregates. Further recrystallization is expressed in the spatial redistribution of grain boundaries and the formation of monomineralic intergrowth boundaries, i.e., the glomerogranular structure of rock and substructures of PGM, chromite, and olivine grains as intermediate types of organization of the granular assemblies in the form of reticulate, chain, and cellular structures and substructures of aggregates.

  15. Aluminium phosphate and phosphate-sulphate minerals in kyanite schists of the Ichetuyskoye area, West Transbaikalia, Russia: crystal chemistry and evolution

    NASA Astrophysics Data System (ADS)

    Izbrodin, Ivan A.; Ripp, German S.; Doroshkevich, Anna G.

    2011-01-01

    Aluminium phosphate and aluminium phosphate-sulphate (APS) minerals occur as disseminated crystals and fine-grained aggregates in kyanite schists near Ichetuyskoye, in the Dzhida basin (West Transbaikal region, Russia). Petrographical, mineralogical and geochemical data suggest a metamorphic evolution through prograde and retrograde stages. Lazulite-scorzalite and trolleite in association with kyanite, quartz, muscovite, paragonite, topaz, rutile, magnetite and hematite formed during the prograde stage. More than 25 minerals identified in schists are genetically related to the retrograde stage. Some phosphates and all of the APS minerals belong to the alunite, beudantite and plumbogummite groups. Electron-microprobe data reveal the presence of wide compositional variations and complex solid-solution series among the members. The main crystal-chemical variations of the APS solid-solution series in the alunite supergroup concern the relative proportions of svanbergite, woodhouseite, goyazite, crandallite, florencite-(Ce) and natroalunite. Chemical analyses of APS minerals indicate extremely high amounts of LREE, Sr, Ba, Ca and Na. In some cases, APS minerals have compositions of Ba and Ca,Ba phosphates- sulphates.

  16. Studies of Quaternary saline lakes - III. Mineral, chemical, and isotopic evidence of salt solution and crystallization processes in Owens Lake, California, 1969-1971

    NASA Astrophysics Data System (ADS)

    Smith, George I.; Friedman, Irving; McLaughlin, Robert J.

    1987-04-01

    As a consequence of the 1969-1970 flooding of normally dry Owens Lake, a 2.4-m-deep lake formed and 20% of the 2-m-thick salt bed dissolved in it. Its desiccation began August 1969, and salts started crystallizing September 1970, ending August 1971. Mineralogic, brine-composition, and stable-isotope data plus field observations showed that while the evolving brine composition established the general crystallization timetable and range of primary and secondary mineral assemblages, it was the daily, monthly, and seasonal temperature changes that controlled the details of timing and mineralogy during this depositional process. Deuterium analyses of lake brine, interstitial brine, and hydrated saline phases helped confirm the sequence of mineral crystallizations and transformations, and they documented the sources and temperatures of waters involved in the reactions. Salts first crystallized as floating rafts on the lake surface. Natron and mirabilite, salts whose solubilities decrease greatly with lowering temperatures, crystallized late at night in winter, when surface-water temperatures reached their minima; trona, nahcolite, burkeite, and halite, salts with solubilities less sensitive to temperature, crystallized during the afternoon in summer, when surface salinities reached their maxima. However, different temperatures were generally associated with crystallization (at the surface) and accumulation (on the lake floor) because short-term temperature changes were transmitted to surface and bottom waters at different rates. Consequently, even when solubilities were exceeded at the surface, salts were preserved or not as a function of bottom-water temperatures. Halite, a nearly temperature-insensitive salt, was always preserved. Monitoring the lake-brine chemistry and mineralogy of the accumulating salts shows: (1) An estimated 0.9 × 10 6 tons of CO 2 was released to the atmosphere or consumed by the lake's biomass prior to most salt crystallization. (2) After

  17. Studies of Quaternary saline lakes-III. Mineral, chemical, and isotopic evidence of salt solution and crystallization processes in Owens Lake, California, 1969-1971

    USGS Publications Warehouse

    Smith, G.I.; Friedman, I.; McLaughlin, R.J.

    1987-01-01

    As a consequence of the 1969-1970 flooding of normally dry Owens Lake, a 2.4-m-deep lake formed and 20% of the 2-m-thick salt bed dissolved in it. Its desiccation began August 1969, and salts started crystallizing September 1970, ending August 1971. Mineralogic, brine-composition, and stable-isotope data plus field observations showed that while the evolving brine composition established the general crystallization timetable and range of primary and secondary mineral assemblages, it was the daily, monthly, and seasonal temperature changes that controlled the details of timing and mineralogy during this depositional process. Deuterium analyses of lake brine, interstitial brine, and hydrated saline phases helped confirm the sequence of mineral crystallizations and transformations, and they documented the sources and temperatures of waters involved in the reactions. Salts first crystallized as floating rafts on the lake surface. Natron and mirabilite, salts whose solubilities decrease greatly with lowering temperatures, crystallized late at night in winter, when surface-water temperatures reached their minima; trona, nahcolite, burkeite, and halite, salts with solubilities less sensitive to temperature, crystallized during the afternoon in summer, when surface salinities reached their maxima. However, different temperatures were generally associated with crystallization (at the surface) and accumulation (on the lake floor) because short-term temperature changes were transmitted to surface and bottom waters at different rates. Consequently, even when solubilities were exceeded at the surface, salts were preserved or not as a function of bottom-water temperatures. Halite, a nearly temperature-insensitive salt, was always preserved. Monitoring the lake-brine chemistry and mineralogy of the accumulating salts shows: (1) An estimated 0.9 ?? 106 tons of CO2 was released to the atmosphere or consumed by the lake's biomass prior to most salt crystallization. (2) After

  18. Crystal chemistry and application development of uranyl extended structure and nanoscale materials and actinyl ion-substituted mineral phases

    NASA Astrophysics Data System (ADS)

    Wylie, Ernest M.

    The worldwide use of nuclear energy presents both significant advantages and challenges for society. Actinide research seeks to address these challenges and drive advancement in the fields of nuclear science and engineering. Here, key aspects of the fuel cycle are examined from both a fundamental and an applications-based perspective. Hydrothermal, ionothermal, room-temperature evaporation, and liquid diffusion synthesis techniques and single-crystal X-ray diffraction were used to study the structures of 18 uranyl compounds and six actinyl-doped mineral phases. These compounds represent a diverse group ranging from unique molecular clusters to novel and known extended structures isolated from aqueous and ionic liquid media. Ultrafiltration techniques were utilized to separate uranyl peroxide nanoclusters from complex aqueous solutions. Inductively coupled plasma optical emission spectroscopy and mass spectrometry were used to quantify elemental distributions in the feed and permeate solutions while Raman spectroscopy, small-angle X-ray scattering, and electrospray ionization mass spectrometry were used to define the characteristics of the cluster species across a range different solution conditions.

  19. The X-ray crystal structure of Shewanella oneidensis OmcA reveals new insight at the microbe-mineral interface

    SciTech Connect

    Edwards, Marcus; Baiden, Nanakow; Johs, Alexander; Tomanicek, Stephen J.; Liang, Liyuan; Shi, Liang; Fredrickson, Jim K.; Zachara, John M.; Gates, Andrew J.; Butt, Julea N.; Richardson, David; Clarke, Thomas A.

    2014-05-21

    The x-ray crystal structure of Shewanella oneidensis OmcA, an extracellular decaheme cytochrome involved in mineral reduction, was solved to a resolution of 2.7 Å. The four OmcA molecules in the asymmetric unit were arranged so the distance between heme-5 on adjacent OmcA monomers was less than 1 nm, indicative of a transient OmcA dimer capable of intermolecular electron transfer. A previously identified hematite binding motif was identified near heme 10, forming a hydroxylated surface that would bring a heme-10 electron egress site to ~ 1 nm of mineral surface.

  20. Background information to accompany folio of geologic, mineral resource, geochemical, aeromagnetic, and gravity maps of the Hillsboro and San Lorenzo quadrangles, Sierra and Grant Counties, New Mexico; with sections on geochemistry and geophysics

    USGS Publications Warehouse

    Hedlund, David Carl; Watts, K.C.; Alminas, Henry V.; Wynn, Jeffrey C.

    1979-01-01

    The Hillsboro and San Lorenzo 15-minute quadrangles of southwestern New Mexico have been mapped at a 1:48,000 scale and selected mineralized areas within these quadrangles have been mapped in greater detail. This area of about 550 mi2 (1,424 km2) is within the southern part of the Black Range and includes much of the Mimbres Mountains and parts of the adjoining Black Range Primitive area. The region is highly mineralized with Laramide (75.1 ? 2.5 m.y.) and middle Tertiary (about 32 to 35 m.y.) intrusions providing the source for much of the base- and precious-metal mineralization. The porphyry copper deposit at Copper Flat is a subvolcanic Laramide quartz monzonite stock that was intruded into a thick section (>2,700 ft or >823 m) of Upper Cretaceous andesite. Numerous gold-bearing veins radiate from the central quartz monzonite stock, and locally offset a radial system of quartz latite dikes. Gold-bearing veins, chiefly along the south and east periphery of the stock, have provided the source for both gold lode and placer deposits. The middle Tertiary rhyolitic plugs, stocks, and dikes have intruded a dominantly carbonate section of Paleozoic sediments and bedding replacement deposits of zinc, lead, and copper are closely associated with tactite in the Carpenter (Swartz) mining district. The rich oxidized silver deposits of the Kingston district are largely fault controlled and a metallizing pluton is not present at the surface outcrop. Some of the silver-bearing base-metal veins in the Kingston district contain rhodochrosite, rhodonite, and alabandite and the highly oxidized parts of these veins have been mined for manganese ore. Very minor amounts of tungsten, as scheelite, occur in thin tactite zones along Tank Canyon, at the Silver Queen claims near Kingston, and at the Silver Tail group of mines along Pierce Canyon.

  1. Crystallization conditions and controls on trace element residence in the main minerals from the Pedra Branca Syenite, Brazil: An electron microprobe and LA-ICPMS study

    NASA Astrophysics Data System (ADS)

    Carvalho, Bruna Borges; Janasi, Valdecir de Assis

    2012-11-01

    Major and trace-element microanalyses of the main minerals from the 610 Ma Pedra Branca Syenite, southeast Brazil, allow inferences on intensive parameters of magmatic crystallization and on the partition of trace-elements among these minerals, with important implications for the petrogenetic evolution of the pluton. Two main syenite types make up the pluton, a quartz-free syenite with tabular alkali feldspar (laminated silica-saturated syenite, LSS, with Na-rich augite + phlogopite + hematite + magnetite + titanite + apatite) and a quartz-bearing syenite (laminated silica-oversaturated syenite, LSO, with scarce corroded plagioclase plus diopside + biotite ± hornblende + ilmenite ± magnetite + titanite + apatite). Both types share a remarkable enrichment in incompatible elements as K, Ba, Sr, P and LREE. Apatite saturation temperatures of ~ 1060-1090 °C are the best estimates of liquidus, whereas the pressure of emplacement, based on Al-in-hornblende barometry, is estimated as 3.3 to 4.8 kbar. Although both units crystallized under oxidizing conditions, oxygen fugacity was probably higher in LSS, as shown by higher mg# of the mafic minerals and higher hematite contents in Hem-Ilmss. In contrast with the Ca-bearing alkali-feldspar from LSO, which hosts most of the whole-rock Sr and Pb, virtually Ca-free alkali-feldspar from LSS hosts ~ 50% of whole-rock Sr and ~ 80% of Pb, the remainder of these elements being shared by apatite, pyroxene and titanite. This contrast reflects a strong crystal-chemical control, whereby a higher proportion of an element with similar ratio and charge (Ca2 +) enhances the residence of Sr and Pb in the M-site of alkali feldspar. The more alkaline character of the LSS magma is inferred to have inhibited zircon saturation; Zr + Hf remained in solution until late in the crystallization, and were mostly accommodated in the structure of Ca-Na pyroxene and titanite, which are one order of magnitude richer in these elements compared to the

  2. Variations in the chemical composition of lamprophyllite-group minerals and the crystal structure of fluorine-rich barytolamprophyllite from new peralkaline dyke

    NASA Astrophysics Data System (ADS)

    Akimenko, M. I.; Aksenov, S. M.; Sorokhtina, N. V.; Kogarko, L. N.; Kononkova, N. N.; Rastsvetaeva, R. K.; Rozenberg, K. A.

    2015-11-01

    The variations in the chemical composition of lamprophyllite-group minerals from a peralkaline dyke of the Mokhnatye Roga area (Kandalaksha region, Kola Peninsula), which are crystallized during the entire period of dyke formation and form several generations, have been investigated. The early generations differ in a steadily high fluorine content, while the later ones exhibit reduced amount of fluorine, impurity elements, and sodium, with a simultaneous increase in the potassium content. The crystal structure of fluorine- rich barytolamprophyllite (potentially a new representative of the lamprophyllite group, differing by the predominance of fluorine in the anion X site) has been analyzed by single crystal X-ray diffraction. This mineral is found to have a monoclinic unit cell with the following parameters: a = 19.5219(8) Å, b = 7.0915(2) Å, c = 5.3925(2) Å, β = 96.628(3)°, and sp. gr. C2/ m. The structure is refined to R = 5.73% in the anisotropic approximation of the atomic displacement parameters using 3668 I > 2σ( I). The idealized formula ( Z = 2) is (Ba,Sr)2[Na(Na,Fe)2(Ti,Mg)F2][Ti2(Si2O7)2O2].

  3. Carboxymethyl cellulose binding to mineral substrates: characterization by atomic force microscopy-based force spectroscopy and quartz-crystal microbalance with dissipation monitoring.

    PubMed

    Pensini, Erica; Yip, Christopher M; O'Carroll, Denis; Sleep, Brent E

    2013-07-15

    The attachment of the sodium salt of carboxymethyl cellulose (CMC) onto iron oxide and various silicate substrates in aqueous solution as a function of salt concentration and pH was studied by atomic force microscopy-based force spectroscopy (AFM) and quartz-crystal microbalance with dissipation monitoring (QCM-D). Both ionic strength and cation valency were found to influence substrate binding. Notably, QCM-D experiments strongly suggested that the solubility of CMC is directly impacted by the presence of CaCl2. Such data are critical for the design of new molecules for stabilizing mineral floc dispersions and for assessing the mobility of CMC-coated particles in the subsurface. Modeling of AFM data with an extended Ohshima theory showed that van der Waals and steric forces played a major role in the interactions between CMC and mineral substrates, and that hydration forces were also important. PMID:23643251

  4. Determination of GaN solubility in supercritical ammonia with NH4F and NH4Cl mineralizer by in situ x-ray imaging of crystal dissolution

    NASA Astrophysics Data System (ADS)

    Schimmel, Saskia; Lindner, Michael; Steigerwald, Thomas G.; Hertweck, Benjamin; Richter, Theresia M. M.; Künecke, Ulrike; Alt, Nicolas S. A.; Niewa, Rainer; Schlücker, Eberhard; Wellmann, Peter J.

    2015-05-01

    Quantitative data on the solubility of GaN in supercritical ammonia using NH4F as mineralizer are reported. The solubility is determined by in situ x-ray imaging of the dissolution of GaN single crystals. First, solubility values obtained by this method with NH4Cl as mineralizer are presented and discussed with respect to existing literature data. Monitoring the dissolution process in situ reveals the time when the solubility limit is reached. Thus, it allows to distinguish the saturation of the solution from dissolution based on mass transport and deposition. This is a key advantage of solubility measurements by in situ x-ray imaging compared to gravimetric methods. Our results indicate that the solubility limit is reached much faster than usually assumed in gravimetric solubility studies and the solubility of GaN in ammonothermal media is significantly lower than reported so far.

  5. Mineralization of the vertebral bodies in Atlantic salmon (Salmo salar L.) is initiated segmentally in the form of hydroxyapatite crystal accretions in the notochord sheath.

    PubMed

    Wang, Shou; Kryvi, Harald; Grotmol, Sindre; Wargelius, Anna; Krossøy, Christel; Epple, Mattias; Neues, Frank; Furmanek, Tomasz; Totland, Geir K

    2013-08-01

    We performed a sequential morphological and molecular biological study of the development of the vertebral bodies in Atlantic salmon (Salmo salar L.). Mineralization starts in separate bony elements which fuse to form complete segmental rings within the notochord sheath. The nucleation and growth of hydroxyapatite crystals in both the lamellar type II collagen matrix of the notochord sheath and the lamellar type I collagen matrix derived from the sclerotome, were highly similar. In both matrices the hydroxyapatite crystals nucleate and accrete on the surface of the collagen fibrils rather than inside the fibrils, a process that may be controlled by a template imposed by the collagen fibrils. Apatite crystal growth starts with the formation of small plate-like structures, about 5 nm thick, that gradually grow and aggregate to form extensive multi-branched crystal arborizations, resembling dendritic growth. The hydroxyapatite crystals are always oriented parallel to the long axis of the collagen fibrils, and the lamellar collagen matrices provide oriented support for crystal growth. We demonstrate here for the first time by means of synchroton radiation based on X-ray diffraction that the chordacentra contain hydroxyapatite. We employed quantitative real-time PCR to study the expression of key signalling molecule transcripts expressed in the cellular core of the notochord. The results indicate that the notochord not only produces and maintains the notochord sheath but also expresses factors known to regulate skeletogenesis: sonic hedgehog (shh), indian hedgehog homolog b (ihhb), parathyroid hormone 1 receptor (pth1r) and transforming growth factor beta 1 (tgfb1). In conclusion, our study provides evidence for the process of vertebral body development in teleost fishes, which is initially orchestrated by the notochord. PMID:23711083

  6. Mineralization of the vertebral bodies in Atlantic salmon (Salmo salar L.) is initiated segmentally in the form of hydroxyapatite crystal accretions in the notochord sheath

    PubMed Central

    Wang, Shou; Kryvi, Harald; Grotmol, Sindre; Wargelius, Anna; Krossøy, Christel; Epple, Mattias; Neues, Frank; Furmanek, Tomasz; Totland, Geir K

    2013-01-01

    We performed a sequential morphological and molecular biological study of the development of the vertebral bodies in Atlantic salmon (Salmo salar L.). Mineralization starts in separate bony elements which fuse to form complete segmental rings within the notochord sheath. The nucleation and growth of hydroxyapatite crystals in both the lamellar type II collagen matrix of the notochord sheath and the lamellar type I collagen matrix derived from the sclerotome, were highly similar. In both matrices the hydroxyapatite crystals nucleate and accrete on the surface of the collagen fibrils rather than inside the fibrils, a process that may be controlled by a template imposed by the collagen fibrils. Apatite crystal growth starts with the formation of small plate-like structures, about 5 nm thick, that gradually grow and aggregate to form extensive multi-branched crystal arborizations, resembling dendritic growth. The hydroxyapatite crystals are always oriented parallel to the long axis of the collagen fibrils, and the lamellar collagen matrices provide oriented support for crystal growth. We demonstrate here for the first time by means of synchroton radiation based on X-ray diffraction that the chordacentra contain hydroxyapatite. We employed quantitative real-time PCR to study the expression of key signalling molecule transcripts expressed in the cellular core of the notochord. The results indicate that the notochord not only produces and maintains the notochord sheath but also expresses factors known to regulate skeletogenesis: sonic hedgehog (shh), indian hedgehog homolog b (ihhb), parathyroid hormone 1 receptor (pth1r) and transforming growth factor beta 1 (tgfb1). In conclusion, our study provides evidence for the process of vertebral body development in teleost fishes, which is initially orchestrated by the notochord. PMID:23711083

  7. Crystal preferred orientations of minerals from mantle xenoliths in alkali basaltic rocks form the Catalan Volcanic Zone (NE Spain)

    NASA Astrophysics Data System (ADS)

    Fernández-Roig, Mercè; Galán, Gumer; Mariani, Elisabetta

    2015-04-01

    Mantle xenoliths in alkali basaltic rocks from the Catalan Volcanic Zone, associated with the Neogene-Quaternary rift system in NE Spain, are formed of anhydrous spinel lherzolites and harzburgites with minor olivine websterites. Both peridotites are considered residues of variable degrees of partial melting, later affected by metasomatism, especially the harzburgites. These and the websterites display protogranular microstructures, whereas lherzolites show continuous variation between protogranular, porphyroclastic and equigranular forms. Thermometric data of new xenoliths indicate that protogranular harzburgites, lherzolites and websterites were equilibrated at higher temperatures than porphyroclastic and equigranular lherzolites. Mineral chemistry also indicates lower equilibrium pressure for porphyroclastic and equigranular lherzolites than for the protogranular ones. Crystal preferred orientations (CPOs) of olivine and pyroxenes from these new xenoliths were determined with the EBSD-SEM technique to identify the deformation stages affecting the lithospheric mantle in this zone and to assess the relationships between the deformation fabrics, processes and microstructures. Olivine CPOs in protogranular harzburgites, lherzolites and a pyroxenite display [010]-fiber patterns characterized by a strong point concentration of the [010] axis normal to the foliation and girdle distribution of [100] and [001] axes within the foliation plane. Olivine CPO symmetry in porphyroclastic and equigranular lherzolites varies continuously from [010]-fiber to orthorhombic and [100]-fiber types. The orthorhombic patterns are characterized by scattered maxima of the three axes, which are normal between them. The rare [100]-fiber patterns display strong point concentration of [100] axis, with normal girdle distribution of the other two axes, which are aligned with each other. The patterns of pyroxene CPOs are more dispersed than those of olivine, especially for clinopyroxene, but

  8. 30 CFR 550.253 - What lease stipulations information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 2 2013-07-01 2013-07-01 false What lease stipulations information must accompany the DPP or DOCD? 550.253 Section 550.253 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT... Coordination Documents (docd) § 550.253 What lease stipulations information must accompany the DPP or DOCD?...

  9. 30 CFR 550.253 - What lease stipulations information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 2 2014-07-01 2014-07-01 false What lease stipulations information must accompany the DPP or DOCD? 550.253 Section 550.253 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT... Coordination Documents (docd) § 550.253 What lease stipulations information must accompany the DPP or DOCD?...

  10. 30 CFR 550.253 - What lease stipulations information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 2 2012-07-01 2012-07-01 false What lease stipulations information must accompany the DPP or DOCD? 550.253 Section 550.253 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT... Coordination Documents (docd) § 550.253 What lease stipulations information must accompany the DPP or DOCD?...

  11. The crystal structure and crystal chemistry of fernandinite and corvusite

    USGS Publications Warehouse

    Evans, H.T., Jr.; Post, J.E.; Ross, D.R.; Nelen, J.A.

    1994-01-01

    Using type material of fernandinite from Minasragra, Peru, and corvusite from the Jack Claim, La Sal Mountains, Utah, the properties and crystal chemistry of these minerals have been determined by Rietveld analysis of the powder X-ray-diffraction patterns. The crystal structure of both species is isotypic with the V2O5 -type layer first found for ??-Ag0.68V2O5; it consists of chains of VO6 octahedra linked by opposite corners (parallel to b) condensed by edge-sharing to form the layer. The vanadium has average valence 4.8, and the resulting layer-charge is balanced by varying amounts of Ca, Na, and K in the interlayer region accompanied by labile water. This study has confirmed the validity of fernandinite as a unique mineral species. It is closely related to corvusite, from which it is distinguished on the basis of the dominant interlayer cation: Ca for fernandinite, Na for curvusite. -Authors

  12. The SHAND quaternary system for evaluating the supersilicic or subsilicic crystal-chemistry of eclogite minerals, and potential new UHPM pyroxene and garnet end-members

    NASA Astrophysics Data System (ADS)

    Smith, D. C.

    2006-09-01

    The stoichiometry of pyroxenes {viiiX2+ viY2+ ivZ4+ 2 O6} and garnets {xiiX2+ 3 viY3+ 2 ivZ4+ 3 O12} is re-evaluated by a theoretical crystal-chemical approach that takes into account natural phenomena that do not fit with conventional anhydrous stoichiometric mineralogy: the existence in eclogites of microinclusions of other minerals that may have been exsolved from previous supersilicic or subsilicic UHPM pyroxene or garnet. Different definitions of supersilicic and subsilicic are discussed and the one based on the ability to exsolve SiO2 and leave behind a stoichiometric pyroxene or garnet is recommended for general adoption. The SHAND system (S = Si et al.; H = H; A = Al et al.; N = Na et al.; D = divalents) for projecting multivariate chemical space involving 23 cations and 104 selected natural or potential mineral species on to two essential diagrams (SAND and SHND) is described in full for the first time. Numerous possible chemical exchanges are considered and justified with respect to known mineral phenomena such as cation vacancies, octahedral silicon or protonation. Several new potential end-members are presented, in particular “supersilipyx”, “supersiligar” and “subsiligar”. It is suggested that small quantities of these end-members can be incorporated into UHPM solid-solutions and lead to various exsolution phenomena during eclogite exhumation.

  13. The Role of Fractional Crystallization and Magma Mixing/Mingling in the Genesis of Karacaali Magmatic Complex (Central Anatolia, Turkey) Fe, Mo-Cu Mineralizations

    NASA Astrophysics Data System (ADS)

    Delibas, O.; Genc, Y.; de Campos, C. P.

    2009-05-01

    This work brings into focus different metal associations (Fe and Mo-Cu) characteristic for the Karacaali Magmatic Complex (KMC), in Central Anatolia, Turkey. The Mo-Cu mineralization is widespread hosted in rhyolitic-rhyodacitic/granidoid rocks or is related to N-S striking vertical quartz-calcite veins. The Fe mineralization, on the other hand, is hosted in gabbroic/basaltic rocks. Field relations and geochronologic studies on single zircons (U-Pb) point towards a coeval temporal relation between plutonites and volcanites. The relatively overlapping ages between monzonite (73.1 Ma) and rhyolitic rocks (67 Ma) reflect a long lasting gradual crystallization within a zoned magma chamber. This is confirmed by progressive transitional contacts from plutonites into volcanites. Based on detailed field, textural and petrographic studies, granitic and monzonitic rocks have been subdivided into four different facies. These are: porphyritic quartz monzonites, quartz-monzonites, fine-grained granites and porphyritic leucogranites. Furthermore, highly diverse textures and structures, which are typical for hybrid rocks, reveal important magma mixing/migling and fractional crystalization processes. From additional geochemical studies, granitic rocks show high Rb/Sr (1.52), nearly flat REE patterns and strong Eu negative anomalies. However; monzonitic and hybrid rocks have relatively low Rb/Sr ratios (0.37 and 0.32) and depleted HREE patterns. Thus, in this complex, granitic rocks are considered as evolved products from the felsic magma. Strong positive Mo-correlation within the granitoids can be explained by a high degree of magmatic fractionation (Ishihara and Tani, 2004). Therefore, last evolved granitic melts are enriched in Mo- rich volatiles giving rise to molybdenite-quartz-calcite veins. Field, macro-micro and chemical studies evidence a co-magmatic origin for the gabbroic/basaltic-hosted Fe-mineralization. Despite the very close relation between compositional character

  14. 30 CFR 250.212 - What information must accompany the EP?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... support facilities information required by § 250.225; (n) Coastal zone management information required by... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What information must accompany the EP? 250.212 Section 250.212 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR OFFSHORE OIL...

  15. 30 CFR 250.242 - What information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ....258; (q) Sulphur operations information required by § 250.259; (r) Coastal zone management information... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What information must accompany the DPP or DOCD? 250.242 Section 250.242 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE...

  16. 30 CFR 250.252 - What environmental monitoring information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What environmental monitoring information must accompany the DPP or DOCD? 250.252 Section 250.252 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Plans and Information Contents of Development...

  17. 30 CFR 250.221 - What environmental monitoring information must accompany the EP?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What environmental monitoring information must accompany the EP? 250.221 Section 250.221 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Plans and Information Contents of Exploration Plans (ep)...

  18. 30 CFR 550.242 - What information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 2 2014-07-01 2014-07-01 false What information must accompany the DPP or DOCD? 550.242 Section 550.242 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE...; (c) Hydrogen sulfide information required by § 550.245; (d) Mineral resource conservation...

  19. 30 CFR 550.242 - What information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 2 2013-07-01 2013-07-01 false What information must accompany the DPP or DOCD? 550.242 Section 550.242 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE...; (c) Hydrogen sulfide information required by § 550.245; (d) Mineral resource conservation...

  20. 30 CFR 250.218 - What air emissions information must accompany the EP?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What air emissions information must accompany the EP? 250.218 Section 250.218 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Plans and Information Contents of Exploration Plans (ep) §...

  1. 30 CFR 250.249 - What air emissions information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What air emissions information must accompany the DPP or DOCD? 250.249 Section 250.249 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Plans and Information Contents of Development and...

  2. Steklite, KAl(SO4)2: A finding at the Tolbachik Volcano, Kamchatka, Russia, validating its status as a mineral species and crystal structure

    NASA Astrophysics Data System (ADS)

    Murashko, M. N.; Pekov, I. V.; Krivovichev, S. V.; Chernyatyeva, A. P.; Yapaskurt, V. O.; Zadov, A. E.; Zelensky, M. E.

    2013-12-01

    Steklite KAl(SO4)2 has been found in sublimates of the Yadovitaya (Poisonous) fumarole at the second cinder cone of the northern breach of the Great Fissure Tolbachik Eruption, Tolbachik volcano, Kamchatka Peninsula, Russia. Steklite was approved as a valid mineral species by the Commission on New Minerals, Nomenclature, and Mineral Classification of the International Mineralogical Association on June 2, 2011 (IMA no. 2011-041). The name steklite is left for this mineral, as it was named by Chesnokov et al. (1995) for its technogenic analog from a burnt dump of coal mine no. 47 at Kopeisk, the Southern Urals, Russia. It is named after the Russian word steklo, meaning glass, in allusion to the visual similarity of its lamellae to thin glass platelets. At Tolbachik, steklite is associated with alumoklyuchevskite, langbeinite, euchlorine, fedotovite, chalcocyanite, hematite, and lyonsite. It occurs as hexagonal or irregular-shaped lamellar crystals with the major form {001} reaching 30 μm in thickness and 0.2 mm (occasionally up to 1 mm) in width. The crystals are frequently split. They are combined into openwork aggregates or thin crusts up to 1.5 × 2.5 cm in area. Steklite is transparent and colorless, with vitreous luster. The cleavage is perfect, parallel to (001). The mineral is brittle. The Mohs' hardness is 2.5. D calc is 2.797 g/cm3. Steklite is optically uniaxial, (-), ω = 1.546(2), ɛ = 1.533(3). The chemical composition (wt %, electron-microprobe data) is as follows: 0.09 Na2O, 18.12 K2O, 0.08 CaO, 0.03 MnO, 2.02 Fe2O3, 18.18 Al2O3, 61.80 SO3. The total is 100.37. The empirical formula calculated on the basis of eight O atoms is: (K0.997Na0.008Ca0.004)Σ1.009(Al0.925Fe{0.066/3+}Mg0.003Mn0.001)Σ0.995S2.01O8. Steklite is trigonal, space group P321, a = 4.7281(3), c = 7.9936(5) Å, V = 154.76(17)Å3, Z =1. The strongest reflections in the X-ray powder diffraction pattern ( d, Å- I[ hkl]) are: 8.02-34[001], 4.085-11[100], 3.649-100[011, 101], 2

  3. A discussion of isotopic systematics and mineral zoning in the shergottites - Evidence for a 180 m.y. igneous crystallization age

    NASA Technical Reports Server (NTRS)

    Jones, J. H.

    1986-01-01

    The chronologies of the Shergotty, Zagami, ALHA 77005, and EETA 79001 meteorites were reexamined on the basis of shergottites' petrography and mineral chemistry data. Among the various isochrons, the concordant Rb-Sr (about 180 Myr) and U-Th-Pb (about 190 Myr) internal isochrons are interpreted as representing the time of igneous crystallization, while the Rb-Sr, Sm-Nd, and Pb-Pb whole-rock isochrons are interpreted as mixing lines, and are reasonably attributed to igneous processes such as wall-rock assimilation and magma mixing. If the approximated age of less than 200 Myr is correct, the shergottites represent the youngest known extraterrestrial basalts. This conclusion supports the hypothesis that the SNC meteorites are samples of Mars.

  4. A new mineral species ferricoronadite, Pb[Mn6 4+(Fe3+, Mn3+)2]O16: mineralogical characterization, crystal chemistry and physical properties

    NASA Astrophysics Data System (ADS)

    Chukanov, Nikita V.; Aksenov, Sergey M.; Jančev, Simeon; Pekov, Igor V.; Göttlicher, Jörg; Polekhovsky, Yury S.; Rusakov, Vyacheslav S.; Nelyubina, Yuliya V.; Van, Konstantin V.

    2016-07-01

    A new mineral ferricoronadite with the simplified formula Pb(Mn6 4+Fe2 3+)O16 was discovered in the orogenetic zone related to the "Mixed Series" metamorphic complex near the Nežilovo village, Pelagonian massif, Republic of Macedonia. Associated minerals are franklinite, gahnite, hetaerolite, roméite, almeidaite, Mn-analogue of plumboferrite, zincohögbomite analogue with Fe3+ > Al, zincochromite, Zn-bearing talc, Zn-bearing muscovite, baryte, quartz and zircon. Ferricoronadite is a late hydrothermal mineral forming veinlets up to 8 mm thick in granular aggregate predominantly composed by zinc-dominant spinels. The new mineral is opaque, black, with brownish black streak. The luster is strong submetallic to metallic. The micro-indentation hardness is 819 kg/mm2. Distinct cleavage is observed on (100). Ferricoronadite is brittle, with uneven fracture. The density calculated from the empirical formula is 5.538 g/cm3. In reflected light, ferricoronadite is light gray. The reflectance values [ R max/ R min, % ( λ, nm)] are: 28.7/27.8 (470), 27.6/26.6 (546), 27.2/26.1 (589), 26.5/25.5 (650). The IR spectrum shows the absence of H2O and OH groups. According to the Mössbauer spectrum, all iron is trivalent. The Mn K-edge XANES spectroscopy shows that Mn is predominantly tetravalent, with subordinate Mn3+. The chemical composition is (wt%; electron microprobe, Mn apportioned between MnO2 and Mn2O3 based on the charge-balance requirement): BaO 5.16, PbO 24.50, ZnO 0.33, Al2O3 0.50, Mn2O3 9.90, Fe2O3 11.45, TiO2 4.19, MnO2 44.81, total 100.84. The empirical formula based on 8 cations Mn + Fe + Ti + Al + Zn pfu is Pb1.03Ba0.32(Mn 4.85 4+ Fe 1.35 3+ Mn 1.18 3+ Ti0.49Al0.09Zn0.04)Σ8.00O16. The crystal structure was determined using single-crystal X-ray diffraction data. The new mineral is tetragonal, space group I4/ m, a = 9.9043(7), c = 2.8986(9) Å, V = 284.34(9) Å3, Z = 1. In ferricoronadite, double chains of edge-sharing (Mn, Fe, Ti)-centered octahedra are connected

  5. A new mineral species ferricoronadite, Pb[Mn6 4+(Fe3+, Mn3+)2]O16: mineralogical characterization, crystal chemistry and physical properties

    NASA Astrophysics Data System (ADS)

    Chukanov, Nikita V.; Aksenov, Sergey M.; Jančev, Simeon; Pekov, Igor V.; Göttlicher, Jörg; Polekhovsky, Yury S.; Rusakov, Vyacheslav S.; Nelyubina, Yuliya V.; Van, Konstantin V.

    2016-04-01

    A new mineral ferricoronadite with the simplified formula Pb(Mn6 4+Fe2 3+)O16 was discovered in the orogenetic zone related to the "Mixed Series" metamorphic complex near the Nežilovo village, Pelagonian massif, Republic of Macedonia. Associated minerals are franklinite, gahnite, hetaerolite, roméite, almeidaite, Mn-analogue of plumboferrite, zincohögbomite analogue with Fe3+ > Al, zincochromite, Zn-bearing talc, Zn-bearing muscovite, baryte, quartz and zircon. Ferricoronadite is a late hydrothermal mineral forming veinlets up to 8 mm thick in granular aggregate predominantly composed by zinc-dominant spinels. The new mineral is opaque, black, with brownish black streak. The luster is strong submetallic to metallic. The micro-indentation hardness is 819 kg/mm2. Distinct cleavage is observed on (100). Ferricoronadite is brittle, with uneven fracture. The density calculated from the empirical formula is 5.538 g/cm3. In reflected light, ferricoronadite is light gray. The reflectance values [R max/R min, % (λ, nm)] are: 28.7/27.8 (470), 27.6/26.6 (546), 27.2/26.1 (589), 26.5/25.5 (650). The IR spectrum shows the absence of H2O and OH groups. According to the Mössbauer spectrum, all iron is trivalent. The Mn K-edge XANES spectroscopy shows that Mn is predominantly tetravalent, with subordinate Mn3+. The chemical composition is (wt%; electron microprobe, Mn apportioned between MnO2 and Mn2O3 based on the charge-balance requirement): BaO 5.16, PbO 24.50, ZnO 0.33, Al2O3 0.50, Mn2O3 9.90, Fe2O3 11.45, TiO2 4.19, MnO2 44.81, total 100.84. The empirical formula based on 8 cations Mn + Fe + Ti + Al + Zn pfu is Pb1.03Ba0.32(Mn{4.85/4+}Fe{1.35/3+}Mn{1.18/3+}Ti0.49Al0.09Zn0.04)Σ8.00O16. The crystal structure was determined using single-crystal X-ray diffraction data. The new mineral is tetragonal, space group I4/m, a = 9.9043(7), c = 2.8986(9) Å, V = 284.34(9) Å3, Z = 1. In ferricoronadite, double chains of edge-sharing (Mn, Fe, Ti)-centered octahedra are connected via

  6. The Effect of Single Crystal Elastic and Plastic Anisotropy on Strain Heterogeneity: Comparison of Olivine to Other Common Minerals

    NASA Astrophysics Data System (ADS)

    Cline, C. J., II; Burnley, P. C.

    2013-12-01

    In order to extrapolate the rheological behavior of polycrystalline earth materials to conditions and timescales that are unachievable in a laboratory setting, some sort of model is required. Numerical models are particularly appealing for this task but for these models to provide a sound platform for extrapolation they must be based on a complete understanding of all deformation mechanics that are operating in the real material. In a simplified description these mechanics can be thought of as having three components 1) the individual grains, 2) the grain boundaries and 3) the macroscopic aggregate response, which can be thought of as the interaction of the other two components within the polycrystal. Traditionally, the aggregate response is thought to represent the summed or average behavior of all individual grains deforming under the influence of the macroscopic stress tensor but; recent work within our lab using finite element models (FEM) has shown that local stress fields within the aggregate are not representative of the macroscopic stress tensor and can vary in both direction and magnitude. These variations in the stress tensor produce a pattern similar to force chains that are observed in deformation experiments on granular materials; and appear to be a direct consequence of stress percolation which is controlled by the anisotropy of the elastic and plastic strengths of the individual grains. To test this hypothesis we will conduct a suite of deformation experiments utilizing multiple monomineralic polycrystals that have a range of single crystal anisotropies. In order to infer the direction of stress acting on each grain and reconstruct the total modulation of stress direction throughout the sample, we have chosen materials that form microstructures that are sensitive to stress direction, such as deformation twins and kink bands. This experimental technique will allow for a direct comparison between the single crystal anisotropy of a material and the

  7. Crystal-structure refinement of zirconium-rich eudialyte and its place among calcium-poor eudialyte-group minerals

    SciTech Connect

    Aksenov, S. M. Rastsvetaeva, R. K.

    2013-09-15

    The repeated refinement of the crystal structure of zirconium-rich eudialyte based on the X-ray diffraction data set collected earlier revealed new structural features. The trigonal unit-cell parameters are a = 14.222(3) A, c = 30.165(5) A, V = 5283.9 A{sup 3}. The refinement resulted in the reduction of the R factor from 0.045 (2347F > 4{sigma}(F)) to 0.035 (3124F > 3{sigma}(F)). It was found that the ordering of Ca and Fe in six-membered rings leads to the lowering of the symmetry to R3. An excess amount of zirconium (more than three atoms per symmetrically independent unit) is located in the M2 microregion in square and five-vertex polyhedral positions. However, this amount is insufficient to be dominant, and the deficiency of zirconium is compensated for by sodium atoms. Based on the new data, zirconium-rich eudialyte can be assigned to the oneillite subtype, being a zirconium-rich and aluminum variety of raslakite.

  8. Ferrous Minerals and Impactite Mineralization at Missouri's Crooked Creek and Decaturville Impact Craters

    NASA Astrophysics Data System (ADS)

    Beauford, R. E.

    2012-03-01

    Epigenetic hydrothermal mineralization, subsequent to the Crooked Creek and Decaturville impacts, accompanied Paleozoic dolomitization of carbonates at a regional scale in the Ozarks and produced quantities of ferrous minerals at both locations.

  9. Analyzing the Deposition of Titanium Dioxide Nanoparticles at Model Rough Mineral Surfaces Using a Quartz Crystal Microbalance with Dissipation Monitoring

    NASA Astrophysics Data System (ADS)

    Li, Y.; Kananizadeh, N.; Rodenhausen, K. B.; Schubert, M.; Bartelt-Hunt, S.

    2015-12-01

    Titanium dioxide nanoparticles (nTiO2) is the most extensively manufactured engineered materials. nTiO2 from sunscreens was found to enter sediments after released into a lake. nTiO2 may also enter the subsurface via irrigation using effluents from wastewater treatment plants. Interaction of nTiO2 with soils and sediments will largely influence their fate, transport, and ecotoxicity. Measuring the interaction between nTiO2 and natural substrates (e.g. such as sands) is particularly challenging due to highly heterogeneous and rough natural sand surfaces. In this study, an engineered controllable rough surface known as three dimensional nanostructured sculptured columnar thin films (SCTFs) has been used to mimic surface roughness. SCTFs were fabricated by glancing angle deposition (GLAD), a physical vapor deposition technique facilitated by electron beam evaporation. Interaction between nTiO2 and SCTF coated surfaces was investigated using a quartz crystal microbalance with dissipation monitoring (QCM-D). In parallel, a Generalized Ellipsometry (GE) was coupled with the QCM-D to measure the deposition of nTiO2. We found that the typical QCM-D modeling approach, e.g. viscoelastic model, would largely overestimate the mass of deposited nTiO2, because the frequency drops due to particle deposition or water entrapment in rough areas were not differentiated. Here, we demonstrate a new approach to model QCM-D data for nTiO2 deposition on rough surfaces, which couples the viscoelastic model with a model of flow on the non-uniform surface.

  10. 30 CFR 250.216 - What biological, physical, and socioeconomic information must accompany the EP?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 2 2011-07-01 2011-07-01 false What biological, physical, and socioeconomic... biological, physical, and socioeconomic information must accompany the EP? If you obtain the following... submitted it to the Regional Supervisor, as accompanying information: (a) Biological environment...

  11. 25 CFR 215.15 - Leases to be accompanied by Form D.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 25 Indians 1 2013-04-01 2013-04-01 false Leases to be accompanied by Form D. 215.15 Section 215.15 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR ENERGY AND MINERALS LEAD AND ZINC MINING OPERATIONS AND LEASES, QUAPAW AGENCY § 215.15 Leases to be accompanied by Form D. Lead and zinc leases...

  12. 30 CFR 550.221 - What environmental monitoring information must accompany the EP?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 2 2013-07-01 2013-07-01 false What environmental monitoring information must... Information Contents of Exploration Plans (ep) § 550.221 What environmental monitoring information must accompany the EP? The following environmental monitoring information, as applicable, must accompany your...

  13. 30 CFR 550.221 - What environmental monitoring information must accompany the EP?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 2 2014-07-01 2014-07-01 false What environmental monitoring information must... Information Contents of Exploration Plans (ep) § 550.221 What environmental monitoring information must accompany the EP? The following environmental monitoring information, as applicable, must accompany your...

  14. 30 CFR 550.252 - What environmental monitoring information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 2 2013-07-01 2013-07-01 false What environmental monitoring information must... Coordination Documents (docd) § 550.252 What environmental monitoring information must accompany the DPP or DOCD? The following environmental monitoring information, as applicable, must accompany your DPP...

  15. 30 CFR 550.221 - What environmental monitoring information must accompany the EP?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 2 2012-07-01 2012-07-01 false What environmental monitoring information must... Information Contents of Exploration Plans (ep) § 550.221 What environmental monitoring information must accompany the EP? The following environmental monitoring information, as applicable, must accompany your...

  16. 30 CFR 550.252 - What environmental monitoring information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 2 2012-07-01 2012-07-01 false What environmental monitoring information must... Coordination Documents (docd) § 550.252 What environmental monitoring information must accompany the DPP or DOCD? The following environmental monitoring information, as applicable, must accompany your DPP...

  17. 30 CFR 550.252 - What environmental monitoring information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 2 2014-07-01 2014-07-01 false What environmental monitoring information must... Coordination Documents (docd) § 550.252 What environmental monitoring information must accompany the DPP or DOCD? The following environmental monitoring information, as applicable, must accompany your DPP...

  18. [Wernicke encephalopathy accompanying linitis plastica].

    PubMed

    Soós, Zsuzsanna; Salamon, Mónika; Oláh, Roland; Czégeni, Anna; Salamon, Ferenc; Folyovich, András; Winkler, Gábor

    2014-01-01

    Wernicke encephalopathy (or Wernicke-Korsakoff encephalopathy) is a rarely diagnosed neurological disorder, which is caused by vitamin B1 deficiency. In the classical form it is characterized by a typical triad (confusion, oculomotor disturbance and ataxia), however, in the majority of the cases only confusion is present. It can be frequently observed in subjects with chronic alcohol consumption, but it may accompany different pathological states of which end stage malignant diseases are the most importants, where confusion may have different backgrounds. The authors present the case of an old male patient with advanced gastric cancer recognised and treated vitamin B1 deficiency, and they draw attention to difficulties of the diagnosis of Wernicke's disease. PMID:24379094

  19. Mineralization by Inhibitor Exclusion

    PubMed Central

    Price, Paul A.; Toroian, Damon; Lim, Joo Eun

    2009-01-01

    One of our goals is to understand the mechanisms that deposit mineral within collagen fibrils, and as a first step we recently determined the size exclusion characteristics of the fibril. This study revealed that apatite crystals up to 12 unit cells in size can access the water within the fibril, whereas molecules larger than a 40-kDa protein are excluded. Based on these observations, we proposed a novel mechanism for fibril mineralization: that macromolecular inhibitors of apatite growth favor fibril mineralization by selectively inhibiting crystal growth in the solution outside of the fibril. To test this mechanism, we developed a system in which crystal formation is driven by homogeneous nucleation at high calcium phosphate concentration and the only macromolecule in solution is fetuin, a 48-kDa inhibitor of apatite growth. Our experiments with this system demonstrated that fetuin determines the location of mineral growth; in the presence of fetuin mineral grows exclusively within the fibril, whereas in its absence mineral grows in solution outside the fibril. Additional experiments showed that fetuin is also able to localize calcification to the interior of synthetic matrices that have size exclusion characteristics similar to those of collagen and that it does so by selectively inhibiting mineral growth outside of these matrices. We termed this new calcification mechanism “mineralization by inhibitor exclusion,” the selective mineralization of a matrix using a macromolecular inhibitor of mineral growth that is excluded from that matrix. Future studies will be needed to evaluate the possible role of this mechanism in bone mineralization. PMID:19414589

  20. 30 CFR 250.223 - What mitigation measures information must accompany the EP?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 2 2011-07-01 2011-07-01 false What mitigation measures information must accompany the EP? 250.223 Section 250.223 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, REGULATION, AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE...

  1. 30 CFR 550.242 - What information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 2 2012-07-01 2012-07-01 false What information must accompany the DPP or DOCD? 550.242 Section 550.242 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Plans and Information Contents of Development and Production Plans...

  2. 30 CFR 250.212 - What information must accompany the EP?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 2 2011-07-01 2011-07-01 false What information must accompany the EP? 250.212 Section 250.212 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, REGULATION, AND ENFORCEMENT...) Geological and geophysical (G&G) information required by § 250.214; (c) Hydrogen sulfide information...

  3. 30 CFR 550.212 - What information must accompany the EP?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 2 2013-07-01 2013-07-01 false What information must accompany the EP? 550.212 Section 550.212 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE...) information required by § 550.214; (c) Hydrogen sulfide information required by § 550.215; (d)...

  4. 30 CFR 550.212 - What information must accompany the EP?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 2 2012-07-01 2012-07-01 false What information must accompany the EP? 550.212 Section 550.212 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Plans and Information Contents of Exploration Plans (ep) § 550.212...

  5. 30 CFR 250.242 - What information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 2 2011-07-01 2011-07-01 false What information must accompany the DPP or DOCD? 250.242 Section 250.242 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, REGULATION, AND...&G information required by § 250.244; (c) Hydrogen sulfide information required by § 250.245;...

  6. 30 CFR 550.212 - What information must accompany the EP?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 2 2014-07-01 2014-07-01 false What information must accompany the EP? 550.212 Section 550.212 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE...) information required by § 550.214; (c) Hydrogen sulfide information required by § 550.215; (d)...

  7. 30 CFR 550.219 - What oil and hazardous substance spills information must accompany the EP?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 2 2013-07-01 2013-07-01 false What oil and hazardous substance spills information must accompany the EP? 550.219 Section 550.219 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Plans and Information Contents...

  8. 30 CFR 550.243 - What general information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 2 2013-07-01 2013-07-01 false What general information must accompany the DPP or DOCD? 550.243 Section 550.243 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Plans and Information Contents of Development and...

  9. 30 CFR 550.213 - What general information must accompany the EP?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 2 2013-07-01 2013-07-01 false What general information must accompany the EP? 550.213 Section 550.213 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Plans and Information Contents of Exploration Plans (ep) §...

  10. Comment on "Evaluation of X-ray diffraction methods for determining the crystal growth mechanisms of clay minerals in mudstones, shales and slates," by L. N. Warr and D. R. Peacor

    USGS Publications Warehouse

    Eberl, D.D.; Srodon, J.; Drits, V.A.

    2003-01-01

    A recent paper by Warr and Peacor (2002) suggested that our use of the Bertaut-Warren-Averbach technique (MudMaster computer program) for studying changes in crystallite thickness distributions (CTDs) of clay minerals during diagenesis and very low-grade metamorphism is not reliable because it is dependent on many variables which can not be fully controlled. Furthermore, the authors implied that the measured shapes of CTDs cannot be used with confidence to deduce crystal growth mechanisms and histories for clays, based on our CTD simulation approach (using the Galoper computer program). We disagree with both points, and show that the techniques are powerful, reliable and useful for studying clay mineral alteration in rocks. ?? 2003 Schweiz. Mineral. Petrogr. Ges.

  11. 10 CFR 9.56 - Accompanying persons.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... for Information, Access Or Amendment of Records Maintained About Them § 9.56 Accompanying persons. An individual requesting access to records about himself may be accompanied by another individual of his own choosing. Both the individual requesting access and the individual accompanying him shall sign the...

  12. 19 CFR 148.4 - Accompanying articles.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 19 Customs Duties 2 2012-04-01 2012-04-01 false Accompanying articles. 148.4 Section 148.4 Customs... (CONTINUED) PERSONAL DECLARATIONS AND EXEMPTIONS General Provisions § 148.4 Accompanying articles. (a) Generally. Articles shall be considered as accompanying a passenger or brought in by him if the...

  13. 19 CFR 148.4 - Accompanying articles.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 19 Customs Duties 2 2014-04-01 2014-04-01 false Accompanying articles. 148.4 Section 148.4 Customs... (CONTINUED) PERSONAL DECLARATIONS AND EXEMPTIONS General Provisions § 148.4 Accompanying articles. (a) Generally. Articles shall be considered as accompanying a passenger or brought in by him if the...

  14. 19 CFR 148.4 - Accompanying articles.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 19 Customs Duties 2 2013-04-01 2013-04-01 false Accompanying articles. 148.4 Section 148.4 Customs... (CONTINUED) PERSONAL DECLARATIONS AND EXEMPTIONS General Provisions § 148.4 Accompanying articles. (a) Generally. Articles shall be considered as accompanying a passenger or brought in by him if the...

  15. 19 CFR 148.4 - Accompanying articles.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 19 Customs Duties 2 2011-04-01 2011-04-01 false Accompanying articles. 148.4 Section 148.4 Customs... (CONTINUED) PERSONAL DECLARATIONS AND EXEMPTIONS General Provisions § 148.4 Accompanying articles. (a) Generally. Articles shall be considered as accompanying a passenger or brought in by him if the...

  16. 19 CFR 148.4 - Accompanying articles.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 2 2010-04-01 2010-04-01 false Accompanying articles. 148.4 Section 148.4 Customs... (CONTINUED) PERSONAL DECLARATIONS AND EXEMPTIONS General Provisions § 148.4 Accompanying articles. (a) Generally. Articles shall be considered as accompanying a passenger or brought in by him if the...

  17. Fluid-rock interaction controlling clay-mineral crystallization in quartz-rich rocks and its influence on the seismicity of the Carboneras fault area (SE Spain)

    NASA Astrophysics Data System (ADS)

    Jimenez-Espinosa, R.; Abad, I.; Jimenez-Millan, J.; Lorite-Herrera, M.

    2009-04-01

    The Carboneras Fault zone is one of the longest fault in the Betic Cordillera (SE Spain) and it would be a good candidate to generate large magnitude earthquakes (Gracia et al., 2006). Seismicity in the region is characterised by low to moderate magnitude events, although large destructive earthquakes have occurred, which reveals significant earthquake and tsunami hazards (Masana et al., 2004). Due to the internal architecture of the fault zone, shear lenses of post-orogenic sediments of Miocene and Pliocene age including marls and sandstones sequences are juxtaposed to the predominant slaty gouges of the Alpine basement. Microcataclasites and gouges of the quartz-rich post-orogenic sediments are also developed as cm- to m-scale bands, allowing the comparison between the deformed materials and their protoliths. Red, yellow and white sandstones and their respective cataclasites can be identified. This communication is concerned with the clay mineral crystallization events in these materials and its possible influence on the seismicity model of the region. The presence of phyllosilicates in fault zones as either neoformed or inherited clays is commonly related with fluid circulation and a mechanically weak fault behaviour (e.g., Wang, 1984). A critical factor for the understanding of the mechanical role of clays in fault rocks is to determine the timing of formation of mineral assemblages and microstructure of fault rocks and protolith. The effects of post-faulting alteration limit inferences about fault behaviour that can be made from exhumed rocks. The Carboneras fault zone provides good opportunities to study mineral processes enhanced by deformation, given that it is located in a region of arid climate and shows outcroppings of quartzitic rocks included in slaty rocks. Combined XRD, optical microscopy and SEM analyses reveal that deformed quartzitic rocks are enriched in phyllosilicates, increasing especially the amount of chlorite. The samples strongly damaged

  18. Electron microprobe mineral analysis guide

    NASA Technical Reports Server (NTRS)

    Brown, R. W.

    1980-01-01

    Electron microprobe mineral analysis guide is a compilation of X-ray tables and spectra recorded from various mineral matrices. Spectra were obtained using electron microprobe, equipped with LiF geared, curved crystal X-ray spectrometers, utilizing typical analytical operating conditions: 15 Kv acceleration potential, 0.02 microampere sample current as measured on a clinopyroxene standard (CP19). Tables and spectra are presented for the majority of elements, fluorine through uranium, occurring in mineral samples from lunar, meteoritic and terrestrial sources. Tables for each element contain relevant analytical information, i.e., analyzing crystal, X-ray peak, background and relative intensity information, X-ray interferences and a section containing notes on the measurement. Originally intended to cover silicates and oxide minerals the tables and spectra have been expanded to cover other mineral phases. Electron microprobe mineral analysis guide is intended as a spectral base to which additional spectra can be added as the analyst encounters new mineral matrices.

  19. Elastic properties of minerals

    SciTech Connect

    Aleksandrov, K.S.; Prodaivoda, G.T.

    1993-09-01

    Investigations of the elastic properties of the main rock-forming minerals were begun by T.V. Ryzhova and K.S. Aleksandrov over 30 years ago on the initiative of B.P. Belikov. At the time, information on the elasticity of single crystals in general, and especially of minerals, was very scanty. In the surveys of that time there was information on the elasticity of 20 or 30 minerals. These, as a rule, did not include the main rock-forming minerals; silicates were represented only by garnets, quartz, topaz, tourmaline, zircon, beryl, and staurolite, which are often found in nature in the form of large and fairly high-quality crystals. Then and even much later it was still necessary to prove a supposition which now seems obvious: The elastic properties of rocks, and hence the velocities of elastic (seismic) waves in the earth`s crust, are primarily determined by the elastic characteristics of the minerals composing these rocks. Proof of this assertion, with rare exceptions of mono-mineralic rocks (marble, quartzite, etc.) cannot be obtained without information on the elasticities of a sufficiently large number of minerals, primarily framework, layer, and chain silicates which constitute the basis of most rocks. This also served as the starting point and main problem of the undertakings of Aleksandrov, Ryzhova, and Belikov - systematic investigations of the elastic properties of minerals and then of various rocks. 108 refs., 7 tabs.

  20. Integrated single crystal laser ablation U/Pb and (U-Th)/He dating of detrital accessory minerals - Proof-of-concept studies of titanites and zircons from the Fish Canyon tuff

    NASA Astrophysics Data System (ADS)

    Horne, Alexandra M.; van Soest, Matthijs C.; Hodges, Kip V.; Tripathy-Lang, Alka; Hourigan, Jeremy K.

    2016-04-01

    Excimer laser technologies enable a rapid and effective approach to simultaneous U/Pb geochronology and (U-Th)/He thermochronology of a wide range of detrital accessory minerals. Here we describe the 'laser ablation double dating' (LADD) method and demonstrate its viability by applying it to zircon and titanite crystals from the well-characterized Fish Canyon tuff. We found that LADD dates for Fish Canyon zircon (206Pb/238U - 28.63 ± 0.11 Ma; (U-Th)/He - 28.38 ± 0.73 Ma) are statistically indistinguishable from those obtained through established, traditional methods of single-crystal dating. The same is true for Fish Canyon titanite LADD dates: 206Pb/238U - 28.08 ± 0.90 Ma; (U-Th)/He - 27.98 ± 0.86 Ma. As anticipated, given that LADD involves the analysis of smaller amounts of material than traditional methods, it yields dates with higher analytical uncertainty. However, this does not substantially reduce the utility of the results for most applications to detrital datasets. An important characteristic of LADD is that it encourages the chemical characterization of crystals by backscattered electron, cathodoluminescence, and/or Raman mapping prior to dating. In addition, by permitting the rapid and robust dating of crystals regardless of the degree of their abrasion during sedimentary transport, the method theoretically should yield dates that are more broadly representative of those of the entire population of detrital crystals in a natural sample.

  1. REE-bearing minerals in the Rapakavi Grante, Southern Finland

    NASA Astrophysics Data System (ADS)

    Al-Ani, Thair

    2015-11-01

    The studied rock samples belong to the classic 1615-1645 Ma Wiborg Rapakivi granite terrane of southeastern Finland. Geochemical studies show that the rapakivi granites and associated rocks form metaluminous to peraluminous A-type granites and plot in the "within plate granites (WPG)" field on the tectonic discriminate diagrams from the Onkamaa, Suomenniemi and Luumäki. The rapakivi granite displays enrichment of light over heavy REE (LREE/HREE = 2-34) and usually negative Eu anomalies (Eu/Eu* = 0.01 - 1.4). Enrichment in REE in some studied samples is confined to highly fractionated portions of the Rapakivi granite. Fractional crystallization of the evolving fluorite-rich peraluminous granitic magma was accompanied, particularly at later stages by fluid fractionation, which plays an important role in the genesis of the REE-mineralization. The studied rapakivi granites host REE-minerals including monazite-(Ce), allanite (Ce), bastnäsite (Ce), xenotime, thorite and REE-bearing mineral apatite. Monazite and allanite are the most important REE carriers in the studied granites and these minerals are strongly enriched in the LREE.Monazites are hosted in apatite, quartz, plagioclase, K-feldspar, and biotite. Grain size of monazite is variable ranging from 50 to >100 μm.Monazite contains 48-68 wt% REE2O3, 24.3-29.3 wt% P2O5 and low Th<1.5 wt%ThO2. The Y, REE, U, Th-bearing minerals are not commonly associated with the primary minerals except for Th-bearing minerals, which occur as silicates (e.g. thorite, ThSiO4); and/or replace other elements in the structure of some accessory mineral, especially xenotime, brabantite, zircon, and apatite. Electron probe microanalysis (EPMA) provides an indication of solid solution series between thorite-xenotimezircon, which are related to hydrothermal solutions enriched in REE, Y, P, U, F, and Zr.

  2. An assessment of calcite crystal growth mechanisms based on crystal size distributions

    USGS Publications Warehouse

    Kile, D.E.; Eberl, D.D.; Hoch, A.R.; Reddy, M.M.

    2000-01-01

    Calcite crystal growth experiments were undertaken to test a recently proposed model that relates crystal growth mechanisms to the shapes of crystal size distributions (CSDs). According to this approach, CSDs for minerals have three basic shapes: (1) asymptotic, which is related to a crystal growth mechanism having constant-rate nucleation accompanied by surface-controlled growth; (2) lognormal, which results from decaying-rate nucleation accompanied by surface-controlled growth; and (3) a theoretical, universal, steady-state curve attributed to Ostwald ripening. In addition, there is a fourth crystal growth mechanism that does not have a specific CSD shape, but which preserves the relative shapes of previously formed CSDs. This mechanism is attributed to supply-controlled growth. All three shapes were produced experimentally in the calcite growth experiments by modifying nucleation conditions and solution concentrations. The asymptotic CSD formed when additional reactants were added stepwise to the surface of solutions that were supersaturated with respect to calcite (initial Ω = 20, where Ω = 1 represents saturation), thereby leading to the continuous nucleation and growth of calcite crystals. Lognormal CSDs resulted when reactants were added continuously below the solution surface, via a submerged tube, to similarly supersaturated solutions (initial Ω = 22 to 41), thereby leading to a single nucleation event followed by surface-controlled growth. The Ostwald CSD resulted when concentrated reactants were rapidly mixed, leading initially to high levels of supersaturation (Ω >100), and to the formation and subsequent dissolution of very small nuclei, thereby yielding CSDs having small crystal size variances. The three CSD shapes likely were produced early in the crystallization process, in the nanometer crystal size range, and preserved during subsequent growth. Preservation of the relative shapes of the CSDs indicates that a supply-controlled growth mechanism

  3. Evaporates, petroleum and mineral resources

    SciTech Connect

    Melvin, J.L.

    1991-01-01

    This book covers oxide minerals under the following topics: oxygen fugacity and its petrologic importance; crystal chemistry of oxides and oxyhydroxides; petrogenetic indicators; oxygen barometry of spinel peridotites; iron-titanium oxides in igneous rocks; oxide minerals in metamorphic rocks; and magnetic petrology.

  4. Orientation of mineral crystallites and mineral density during skeletal development in mice deficient in tissue nonspecific alkaline phosphatase.

    PubMed

    Tesch, W; Vandenbos, T; Roschgr, P; Fratzl-Zelman, N; Klaushofer, K; Beertsen, W; Fratzl, P

    2003-01-01

    Tissue nonspecific alkaline phosphatase (TNALP) is thought to play an important role in mineralization processes, although its exact working mechanism is not known. In the present investigation we have studied mineral crystal characteristics in the developing skeleton of TNALP-deficient mice. Null mutants (n = 7) and their wild-type littermates (n = 7) were bred and killed between 8 and 22 days after birth. Skeletal tissues were processed to assess mineral characteristics (small angle X-ray scattering, quantitative backscattered electron imaging), and to analyze bone by light microscopy and immunolabeling. The results showed a reduced longitudinal growth and a strongly delayed epiphyseal ossification in the null mutants. This was accompanied by disturbances in mineralization pattern, in that crystallites were not orderly aligned with respect to the longitudinal axis of the cortical bone. Among the null mutants, a great variability in the mineralization parameters was noticed. Also, immunolabeling of osteopontin (OPN) revealed an abnormal distribution pattern of the protein within the bone matrix. Whereas in the wild-type animals OPN was predominantly observed in cement and reversal lines, in the null mutants, OPN was also randomly dispersed throughout the nonmineralized matrix, with focal densities. In contrast, the distribution pattern of osteocalcin (OC) was comparable in both types of animals. It is concluded that ablation of TNALP results not only in hypomineralization of the skeleton, but also in a severe disorder of the mineral crystal alignment pattern in the corticalis of growing long bone in association with a disordered matrix architecture, presumably as a result of impaired bone remodeling and maturation. PMID:12510812

  5. Crystal chemical effects on the partitioning of trace elements between mineral and melt - An experimental study of melilite with applications to refractory inclusions from carbonaceous chondrites

    NASA Technical Reports Server (NTRS)

    Beckett, John R.; Spivack, Arthur J.; Hutcheon, Ian D.; Wasserburg, G. J.; Stolper, Edward M.

    1990-01-01

    Results are presented on the partitioning experiments for trace elements Be, Sc, Ba, La, Ce, and Tm between melilite and melt for a bulk composition relevant to Type B inclusions, using a technique, described by Brody and Flemings (1966), by which distributon coeffecients can be obtained over the entire range of crystallization from trace element analysis of a single zoned crystal. Zoned crystals of melilite were grown during controlled cooling rate experiments, and trace element concentrations were determined by SIMS. At each step in the crystal growth, trace element concentrations in the coexisting melt were determined by mass balance, using stepwise integration of a Rayleigh fractionation equation.

  6. Crystal chemical effects on the partitioning of trace elements between mineral and melt - an experimental study of melilite with applications to refractory inclusions from carbonaceous chondrites

    NASA Astrophysics Data System (ADS)

    Beckett, J. R.; Spivack, A. J.; Hutcheon, I. D.; Wasserburg, G. J.; Stolper, E. M.

    1990-06-01

    Results are presented on the partitioning experiments for trace elements Be, Sc, Ba, La, Ce, and Tm between melilite and melt for a bulk composition relevant to Type B inclusions, using a technique, described by Brody and Flemings (1966), by which distributon coeffecients can be obtained over the entire range of crystallization from trace element analysis of a single zoned crystal. Zoned crystals of melilite were grown during controlled cooling rate experiments, and trace element concentrations were determined by SIMS. At each step in the crystal growth, trace element concentrations in the coexisting melt were determined by mass balance, using stepwise integration of a Rayleigh fractionation equation.

  7. Protein Crystallization

    NASA Technical Reports Server (NTRS)

    Chernov, Alexander A.

    2005-01-01

    Nucleation, growth and perfection of protein crystals will be overviewed along with crystal mechanical properties. The knowledge is based on experiments using optical and force crystals behave similar to inorganic crystals, though with a difference in orders of magnitude in growing parameters. For example, the low incorporation rate of large biomolecules requires up to 100 times larger supersaturation to grow protein, rather than inorganic crystals. Nucleation is often poorly reproducible, partly because of turbulence accompanying the mixing of precipitant with protein solution. Light scattering reveals fluctuations of molecular cluster size, its growth, surface energies and increased clustering as protein ages. Growth most often occurs layer-by-layer resulting in faceted crystals. New molecular layer on crystal face is terminated by a step where molecular incorporation occurs. Quantitative data on the incorporation rate will be discussed. Rounded crystals with molecularly disordered interfaces will be explained. Defects in crystals compromise the x-ray diffraction resolution crucially needed to find the 3D atomic structure of biomolecules. The defects are immobile so that birth defects stay forever. All lattice defects known for inorganics are revealed in protein crystals. Contribution of molecular conformations to lattice disorder is important, but not studied. This contribution may be enhanced by stress field from other defects. Homologous impurities (e.g., dimers, acetylated molecules) are trapped more willingly by a growing crystal than foreign protein impurities. The trapped impurities induce internal stress eliminated in crystals exceeding a critical size (part of mni for ferritin, lysozyme). Lesser impurities are trapped from stagnant, as compared to the flowing, solution. Freezing may induce much more defects unless quickly amorphysizing intracrystalline water.

  8. Mineral Chart

    MedlinePlus

    ... How Can I Help a Friend Who Cuts? Mineral Chart KidsHealth > For Teens > Mineral Chart Print A A A Text Size en ... sources of calcium. You'll also find this mineral in broccoli and dark green, leafy vegetables. Soy ...

  9. Mineral oils

    NASA Technical Reports Server (NTRS)

    Furby, N. W.

    1973-01-01

    The characteristics of lubricants made from mineral oils are discussed. Types and compositions of base stocks are reviewed and the product demands and compositions of typical products are outlined. Processes for commercial production of mineral oils are examined. Tables of data are included to show examples of product types and requirements. A chemical analysis of three types of mineral oils is reported.

  10. Carbon Mineral Ecology: Predicting the Undiscovered Minerals of Carbon

    NASA Astrophysics Data System (ADS)

    Hazen, R. M.; Hummer, D. R.; Downs, R. T.; Hystad, G.; Golden, J.

    2015-12-01

    The diversity and distribution of Earth's minerals through deep time reflects key events in our planet's crustal evolution. Studies in mineral ecology exploit mineralogical databases to document diversity-distribution relationships of minerals, which reveal that all carbon-bearing minerals, as well as subsets containing C with O, H, Ca, or Na, conform to Large Number of Rare Events (LNRE) distributions. LNRE models facilitate prediction of total mineral diversity, and thus point to minerals that exist on Earth but have not yet been discovered and described. Our model predicts that at least 548 C minerals exist on Earth today, indicating that at least 145 carbon-bearing mineral species have yet to be discovered. Furthermore, by analyzing subsets of the most common additional elements in carbon-bearing minerals (i.e., 378 C + O species; 282 C + H species; 133 C + Ca species; and 100 C + Na species), we predict that 129 of these missing carbon minerals contain oxygen, 118 contain hydrogen, 52 contain calcium, and more than 60 contain sodium. The majority of these as yet undescribed minerals are predicted to be hydrous carbonates, many of which may have been overlooked because they are colorless, poorly crystalized, and/or water-soluble. We propose the identities of plausible as yet undescribed carbon minerals, as well as search strategies for their discovery. Some of these minerals will be natural examples of known synthetic compounds, including carbides such as calcium carbide (CaC2), crystalline hydrocarbons such as pyrene (C16H10), and numerous oxalates, anhydrous carbonates, and hydrous carbonates. Many other missing carbon minerals will be isomorphs of known carbon minerals, notably of the more than 100 different hydrous carbonate structures. An understanding of Earth's "missing" minerals provides a more complete picture of geochemical processes that influence crustal evolution.

  11. The VLab repository of thermodynamics and thermoelastic properties of minerals

    NASA Astrophysics Data System (ADS)

    Da Silveira, P. R.; Sarkar, K.; Wentzcovitch, R. M.; Shukla, G.; Lindemann, W.; Wu, Z.

    2015-12-01

    Thermodynamics and thermoelastic properties of minerals at planetary interior conditions are essential as input for geodynamics simulations and for interpretation of seismic tomography models. Precise experimental determination of these properties at such extreme conditions is very challenging. Therefore, ab initio calculations play an essential role in this context, but at the cost of great computational effort and memory use. Setting up a widely accessible and versatile mineral physics database can relax unnecessary repetition of such computationally intensive calculations. Access to such data facilitates transactional interaction across fields and can advance more quickly insights about deep Earth processes. Hosted by the Minnesota Supercomputing Institute, the Virtual Laboratory for Earth and Planetary Materials (VLab) was designed to develop and promote the theory of planetary materials using distributed, high-throughput quantum calculations. VLab hosts an interactive database of thermodynamics and thermoelastic properties or minerals computed by ab initio. Such properties can be obtained according to user's preference. The database is accompanied by interactive visualization tools, allowing users to repeat and build upon previously published results. Using VLab2015, we have evaluated thermoelastic properties, such as elastic coefficients (Cij), Voigt, Reuss, and Voigt-Reuss-Hill aggregate averages for bulk (K) and shear modulus (G), shear wave velocity (VS), longitudinal wave velocity (Vp), and bulk sound velocity (V0) for several important minerals. Developed web services are general and can be used for crystals of any symmetry. Results can be tabulated, plotted, or downloaded from the VLab website according to user's preference.

  12. 30 CFR 550.214 - What geological and geophysical (G&G) information must accompany the EP?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 2 2013-07-01 2013-07-01 false What geological and geophysical (G&G) information must accompany the EP? 550.214 Section 550.214 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT... description. A geological description of the prospect(s). (b) Structure contour maps. Current...

  13. 30 CFR 550.214 - What geological and geophysical (G&G) information must accompany the EP?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 2 2014-07-01 2014-07-01 false What geological and geophysical (G&G) information must accompany the EP? 550.214 Section 550.214 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT... description. A geological description of the prospect(s). (b) Structure contour maps. Current...

  14. 30 CFR 550.244 - What geological and geophysical (G&G) information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 2 2012-07-01 2012-07-01 false What geological and geophysical (G&G) information must accompany the DPP or DOCD? 550.244 Section 550.244 Mineral Resources BUREAU OF OCEAN ENERGY... description. A geological description of the prospect(s). (b) Structure contour maps. Current...

  15. 30 CFR 550.214 - What geological and geophysical (G&G) information must accompany the EP?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 2 2012-07-01 2012-07-01 false What geological and geophysical (G&G) information must accompany the EP? 550.214 Section 550.214 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT... description. A geological description of the prospect(s). (b) Structure contour maps. Current...

  16. 30 CFR 550.244 - What geological and geophysical (G&G) information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 2 2013-07-01 2013-07-01 false What geological and geophysical (G&G) information must accompany the DPP or DOCD? 550.244 Section 550.244 Mineral Resources BUREAU OF OCEAN ENERGY... description. A geological description of the prospect(s). (b) Structure contour maps. Current...

  17. 30 CFR 250.214 - What geological and geophysical (G&G) information must accompany the EP?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 2 2011-07-01 2011-07-01 false What geological and geophysical (G&G) information must accompany the EP? 250.214 Section 250.214 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT... contour maps. Current structure contour maps (depth-based, expressed in feet subsea) drawn on the top...

  18. 30 CFR 550.244 - What geological and geophysical (G&G) information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 2 2014-07-01 2014-07-01 false What geological and geophysical (G&G) information must accompany the DPP or DOCD? 550.244 Section 550.244 Mineral Resources BUREAU OF OCEAN ENERGY... description. A geological description of the prospect(s). (b) Structure contour maps. Current...

  19. 30 CFR 550.250 - What oil and hazardous substance spills information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 2 2013-07-01 2013-07-01 false What oil and hazardous substance spills information must accompany the DPP or DOCD? 550.250 Section 550.250 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Plans and Information Contents...

  20. 30 CFR 250.244 - What geological and geophysical (G&G) information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) information must accompany the DPP or DOCD? 250.244 Section 250.244 Mineral Resources MINERALS MANAGEMENT... Supervisor. (f) Shallow hazards assessment. For each proposed well, an assessment of any seafloor and... SHELF Plans and Information Contents of Development and Production Plans (dpp) and...

  1. 30 CFR 250.214 - What geological and geophysical (G&G) information must accompany the EP?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) information must accompany the EP? 250.214 Section 250.214 Mineral Resources MINERALS MANAGEMENT SERVICE... already submitted it to the Regional Supervisor. (f) Shallow hazards assessment. For each proposed well, an assessment of any seafloor and subsurface geological and manmade features and conditions that...

  2. Electronic and optical characteristics of an m-plane GaN single crystal grown by hydride vapor phase epitaxy on a GaN seed synthesized by the ammonothermal method using an acidic mineralizer

    NASA Astrophysics Data System (ADS)

    Kojima, Kazunobu; Tsukada, Yusuke; Furukawa, Erika; Saito, Makoto; Mikawa, Yutaka; Kubo, Shuichi; Ikeda, Hirotaka; Fujito, Kenji; Uedono, Akira; Chichibu, Shigefusa F.

    2016-05-01

    Fundamental electronic and optical properties of a low-resistivity m-plane GaN single crystal, which was grown by hydride vapor phase epitaxy on a bulk GaN seed crystal synthesized by the ammonothermal method in supercritical ammonia using an acidic mineralizer, were investigated. The threading dislocation and basal-plane staking-fault densities of the crystal were around 104 cm-2 and less than 100 cm-1, respectively. Oxygen doping achieved a high electron concentration of 4 × 1018 cm-3 at room temperature. Accordingly, a photoluminescence (PL) band originating from the recombination of hot carriers was observed at low temperatures, even under weak excitation conditions. The simultaneous realization of low-level incorporation of Ga vacancies (VGa) less than 1016 cm-3 was confirmed by using the positron annihilation technique. Consistent with our long-standing claim that VGa complexes are the major nonradiative recombination centers in GaN, the fast-component PL lifetime of the near-band-edge emission at room temperature longer than 2 ns was achieved.

  3. 30 CFR 550.216 - What biological, physical, and socioeconomic information must accompany the EP?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 2 2013-07-01 2013-07-01 false What biological, physical, and socioeconomic... and Information Contents of Exploration Plans (ep) § 550.216 What biological, physical, and... Regional Supervisor, as accompanying information: (a) Biological environment reports....

  4. 30 CFR 550.216 - What biological, physical, and socioeconomic information must accompany the EP?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 2 2012-07-01 2012-07-01 false What biological, physical, and socioeconomic... and Information Contents of Exploration Plans (ep) § 550.216 What biological, physical, and... Regional Supervisor, as accompanying information: (a) Biological environment reports....

  5. 30 CFR 250.216 - What biological, physical, and socioeconomic information must accompany the EP?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What biological, physical, and socioeconomic... and Information Contents of Exploration Plans (ep) § 250.216 What biological, physical, and... Regional Supervisor, as accompanying information: (a) Biological environment reports....

  6. 30 CFR 550.216 - What biological, physical, and socioeconomic information must accompany the EP?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 2 2014-07-01 2014-07-01 false What biological, physical, and socioeconomic... and Information Contents of Exploration Plans (ep) § 550.216 What biological, physical, and... Regional Supervisor, as accompanying information: (a) Biological environment reports....

  7. 30 CFR 250.215 - What hydrogen sulfide (H2S) information must accompany the EP?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... methodologies outlined in 40 CFR part 68. ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What hydrogen sulfide (H2S) information must... Contents of Exploration Plans (ep) § 250.215 What hydrogen sulfide (H2S) information must accompany the...

  8. 30 CFR 250.221 - What environmental monitoring information must accompany the EP?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 2 2011-07-01 2011-07-01 false What environmental monitoring information must... monitoring information must accompany the EP? The following environmental monitoring information, as... monitoring systems that are measuring, or will measure, environmental conditions or will provide...

  9. 30 CFR 250.252 - What environmental monitoring information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 2 2011-07-01 2011-07-01 false What environmental monitoring information must... Development Operations Coordination Documents (docd) § 250.252 What environmental monitoring information must accompany the DPP or DOCD? The following environmental monitoring information, as applicable, must...

  10. 30 CFR 250.251 - If I propose activities in the Alaska OCS Region, what planning information must accompany the DPP?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false If I propose activities in the Alaska OCS Region, what planning information must accompany the DPP? 250.251 Section 250.251 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Plans and...

  11. Mineral Carbonation Employing Ultramafic Mine Waste

    NASA Astrophysics Data System (ADS)

    Southam, G.; McCutcheon, J.; Power, I. M.; Harrison, A. L.; Wilson, S. A.; Dipple, G. M.

    2014-12-01

    Carbonate minerals are an important, stable carbon sink being investigated as a strategy to sequester CO2 produced by human activity. A natural playa (Atlin, BC, CAN) that has demonstrated the ability to microbially-accelerate hydromagnesite formation was used as an experimental model. Growth of microbial mats from Atlin, in a 10 m long flow-through bioreactor catalysed hydromagnesite precipitation under 'natural' conditions. To enhance mineral carbonation, chrysotile from the Clinton Creek Asbestos Mine (YT, CAN) was used as a target substrate for sulphuric acid leaching, releasing as much as 94% of the magnesium into solution via chemical weathering. This magnesium-rich 'feedstock' was used to examine the ability of the microbialites to enhance carbonate mineral precipitation using only atmospheric CO2 as the carbon source. The phototrophic consortium catalysed the precipitation of platy hydromagnesite [Mg5(CO3)4(OH)2·4H2O] accompanied by magnesite [MgCO3], aragonite [CaCO3], and minor dypingite [Mg5(CO3)4(OH)2·5H2O]. Scanning Electron Microscopy-Energy Dispersive Spectroscopy indicated that cell exteriors and extracellular polymeric substances (EPS) served as nucleation sites for carbonate precipitation. In many cases, entire cyanobacteria filaments were entombed in magnesium carbonate coatings, which appeared to contain a framework of EPS. Cell coatings were composed of small crystals, which intuitively resulted from rapid crystal nucleation. Excess nutrient addition generated eutrophic conditions in the bioreactor, resulting in the growth of a pellicle that sealed the bioreactor contents from the atmosphere. The resulting anaerobic conditions induced fermentation and subsequent acid generation, which in turn caused a drop in pH to circumneutral values and a reduction in carbonate precipitation. Monitoring of the water chemistry conditions indicated that a high pH (> 9.4), and relatively high concentrations of magnesium (> 3000 ppm), compared with the natural

  12. The sequence and origin of mineralization in the tectonic zones in the Suwalki Anorthosite Massif, NE Poland

    NASA Astrophysics Data System (ADS)

    Wiszniewska, J.; Cymerman, Z.; Gaweda, A.

    2003-04-01

    crystallization of the teeth-like idiomorphic C_3 carbonate accompanied by the trioctahedral smectite and locally interrupted by the precipitation of fine-grained quartz, due to the changes of fluid composition / the concentration of silica. The crystallization of C_3 calcite continued in the open fissures and was followed by idiomorphic to hipidiomorphic barite precipitation. The last mineral in the crystallization sequence was anhydrite, sometimes accompanied by quartz, forming both the late-stage, post-deformational filling of the composite mineral veins as well as the irregular impregnations in the deformed and kaolinitized host rocks. The composite mineralization is supposed to be originated from the mixed hydrothermal to hypergenic fluids with admixture of marine-type sulphate waters in the last stage of mineralization.

  13. Industrial Minerals.

    ERIC Educational Resources Information Center

    Brady, Lawrence L.

    1983-01-01

    Discusses trends in and factors related to the production of industrial minerals during 1982, indicating that, as 1981 marked a downturn in production of industrial minerals, 1982 continued the trend with temporary and permanent cutbacks in mine and plant production. Includes highlights of several conferences/conference papers in this field.…

  14. Biomineralization: mineral formation by organisms

    NASA Astrophysics Data System (ADS)

    Addadi, Lia; Weiner, Steve

    2014-09-01

    Organisms form many different types of minerals, with diverse shapes and sizes. These minerals fulfill a variety of functions. Inspired by the late H A Lowenstam, Steve Weiner and Lia Addadi have addressed many questions that relate to the mechanisms by which biological organisms produce these mineral phases and how their structures relate to their functions. Addadi and Weiner have explored the manner in which macromolecules extracted from mineralized tissues can interact with some crystal planes and not others, how these macromolecules can be occluded inside the forming crystals residing preferentially on specific crystal planes, and how they can induce one polymorph of calcium carbonate and not another to nucleate. Addadi and Weiner have also identified a novel strategy used by the sea urchin to form its smooth and convoluted mineralized skeletal elements. The strategy involves the initial production by cells of a highly disordered mineral precursor phase in vesicles, and then the export of this so-called amorphous phase to the site of skeletal formation, where it crystallizes. This strategy is now known to be used by many different invertebrate phyla, as well as by vertebrates to build bones and teeth. One of the major current research aims of the Weiner--Addadi group is to understand the biomineralization pathways whereby ions are extracted from the environment, are transported and deposited inside cells within vesicles, how these disordered phases are then transferred to the site of skeletal formation, and finally how the so-called amorphous phase crystallizes. Biology has clearly evolved unique strategies for forming crystalline minerals. Despite more than 300 years of research in this field, many challenging questions still remain unanswered.

  15. Crystal structure of the (Mg,Fe)[UO{sub 2}(P,As)O{sub 4}]{sub 2} . 10H{sub 2}O solid solution-A novel mineral variety of saleeite

    SciTech Connect

    Yakubovich, O. V.; Steele, I. M.; Atencio, D.; Menezes, L. A.; Chukanov, N. V.

    2008-09-15

    The crystal structure of a novel variety {l_brace}[(Mg{sub 0.81}Fe{sub 0.19})(H{sub 2}O){sub 6}](H{sub 2}O){sub 4}{r_brace}{l_brace}(UO{sub 2})[(P{sub 0.67}As{sub 0.33})O{sub 4}]{r_brace}{sub 2} of the mineral saleeite is determined using X-ray diffraction (Bruker Smart diffractometer, {lambda}MoK{sub {alpha}}, graphite monochromator, 2{theta}{sub max} = 56.62{sup o}, R = 0.0321 for 2317 reflections, T = 100 K). The main crystal data are as follows: a = 6.952(6) A, b = 19.865(5) A, c = 6.969(2) A, {beta} = 90.806(4){sup o}, space group P12{sub 1}/n1, Z = 2, and {rho}{sub calcd} = 3.34 g/cm{sup 3}. It is shown that the structure is formed by alternating (along the [010] direction) anionic layers, which are composed of uranium bipyramids and T(P,As) tetrahedra, and cation layers consisting of M(Mg,Fe) octahedra and water molecules, which are joined through a system of asymmetric hydrogen bonds. The hydrogen atoms are located, the scheme of hydrogen bonds is established, and their geometric characteristics are calculated.

  16. Mechanical surface waves accompany action potential propagation.

    PubMed

    El Hady, Ahmed; Machta, Benjamin B

    2015-01-01

    Many diverse studies have shown that a mechanical displacement of the axonal membrane accompanies the electrical pulse defining the action potential (AP). We present a model for these mechanical displacements as arising from the driving of surface wave modes in which potential energy is stored in elastic properties of the neuronal membrane and cytoskeleton while kinetic energy is carried by the axoplasmic fluid. In our model, these surface waves are driven by the travelling wave of electrical depolarization characterizing the AP, altering compressive electrostatic forces across the membrane. This driving leads to co-propagating mechanical displacements, which we term Action Waves (AWs). Our model allows us to estimate the shape of the AW that accompanies any travelling wave of voltage, making predictions that are in agreement with results from several experimental systems. Our model can serve as a framework for understanding the physical origins and possible functional roles of these AWs. PMID:25819404

  17. Ocular myasthenia gravis accompanied by anosmia.

    PubMed

    Chen, Ying; Wang, Li; Zhou, Li; Gao, Ying

    2016-02-01

    We report a case of ocular myasthenia gravis (MG) accompanied by anosmia. A 76-year-old man had idiopathic anosmia of 2-year duration. Four months before consultation, he began to have drooping in the right upper eyelid along with muscle soreness, distension, and pain in the nape. His tongue was dark-red with a thin and white coating; his pulse was wiry and slippery. According to Traditional Chinese Medicine, eyelid drooping and anosmia are the main signs of liver constraint and spleen deficiency. In Western Medicine, the diagnosis was ocular MG and idiopathic anosmia. Our patient, along with the literature, suggests that anosmia may be an early symptom before MG. MG accompanied by anosmia could be a special subtype of MG according to antibody production and symptoms. PMID:26946629

  18. Mechanical surface waves accompany action potential propagation

    NASA Astrophysics Data System (ADS)

    El Hady, Ahmed; Machta, Benjamin B.

    2015-03-01

    Many diverse studies have shown that a mechanical displacement of the axonal membrane accompanies the electrical pulse defining the action potential (AP). We present a model for these mechanical displacements as arising from the driving of surface wave modes in which potential energy is stored in elastic properties of the neuronal membrane and cytoskeleton while kinetic energy is carried by the axoplasmic fluid. In our model, these surface waves are driven by the travelling wave of electrical depolarization characterizing the AP, altering compressive electrostatic forces across the membrane. This driving leads to co-propagating mechanical displacements, which we term Action Waves (AWs). Our model allows us to estimate the shape of the AW that accompanies any travelling wave of voltage, making predictions that are in agreement with results from several experimental systems. Our model can serve as a framework for understanding the physical origins and possible functional roles of these AWs.

  19. Metastatic Basal Cell Carcinoma Accompanying Gorlin Syndrome

    PubMed Central

    Bilir, Yeliz; Gokce, Erkan; Ozturk, Banu; Deresoy, Faik Alev; Yuksekkaya, Ruken; Yaman, Emel

    2014-01-01

    Gorlin-Goltz syndrome or basal cell nevus syndrome is an autosomal dominant syndrome characterized by skeletal anomalies, numerous cysts observed in the jaw, and multiple basal cell carcinoma of the skin, which may be accompanied by falx cerebri calcification. Basal cell carcinoma is the most commonly skin tumor with slow clinical course and low metastatic potential. Its concomitance with Gorlin syndrome, resulting from a mutation in a tumor suppressor gene, may substantially change morbidity and mortality. A 66-year-old male patient with a history of recurrent basal cell carcinoma was presented with exophthalmus in the left eye and the lesions localized in the left lateral orbita and left zygomatic area. His physical examination revealed hearing loss, gapped teeth, highly arched palate, and frontal prominence. Left orbital mass, cystic masses at frontal and ethmoidal sinuses, and multiple pulmonary nodules were detected at CT scans. Basal cell carcinoma was diagnosed from biopsy of ethmoid sinus. Based on the clinical and typical radiological characteristics (falx cerebri calcification, bifid costa, and odontogenic cysts), the patient was diagnosed with metastatic skin basal cell carcinoma accompanied by Gorlin syndrome. Our case is a basal cell carcinoma with aggressive course accompanying a rarely seen syndrome. PMID:25506011

  20. Mineral Quantification.

    PubMed

    2016-01-01

    Optimal intakes of elements, such as sodium, potassium, magnesium, calcium, manganese, copper, zinc and iodine, can reduce individual risk factors including those related to cardiovascular diseases among humans and animals. In order to meet the need for vitamins, major minerals, trace minerals, fatty acids and amino acids, it is necessary to include a full spectrum programme that can deliver all of the nutrients in the right ratio. Minerals are required for normal growth, activities of muscles, skeletal development (such as calcium), cellular activity, oxygen transport (copper and iron), chemical reactions in the body, intestinal absorption (magnesium), fluid balance and nerve transmission (sodium and potassium), as well as the regulation of the acid base balance (phosphorus). The chapter discusses the chemical and instrumentation techniques used for estimation of minerals such as N, P, Ca, Mg, K, Na, Fe, Cu, Zn, B and Mb. PMID:26939263

  1. Clay Minerals

    SciTech Connect

    Mueller, Karl T.; Sanders, Rebecca L.; Washton, Nancy M.

    2014-03-14

    Clay minerals are important components of the environment and are involved or implicated in processes such as the uptake of pollutants and the release of nutrients and as potential platforms for a number of chemical reactions. Owing to their small particle sizes (typically, on the order of microns or smaller) and mixing with a variety of other minerals and soil components, advanced characterization methods are needed to study their structures, dynamics, and reactivities. In this article, we describe the use of solid-state NMR methods to characterize the structures and chemistries of clay minerals. Early one-pulse magic-angle spinning (MAS) NMR studies of 27Al and 29Si have now been enhanced and extended with new studies utilizing advanced methodologies (such as Multiple Quantum MAS) as well as studies of less-sensitive nuclei. In additional work, the issue of reactivity of clay minerals has been addressed, including studies of reactive surface area in the environment. Utilizations of NMR-sensitive nuclides within the clay minerals themselves, and in molecules that react with specific sites on the clay mineral surfaces, have aided in understanding the reactivity of these complex aluminosilicate systems.

  2. Volcanic facies and mineral chemistry of Tertiary volcanics in the northern part of the Eastern Pontides, northeast Turkey: implications for pre-eruptive crystallization conditions and magma chamber processes

    NASA Astrophysics Data System (ADS)

    Yücel, Cem; Arslan, Mehmet; Temizel, İrfan; Abdioğlu, Emel

    2014-06-01

    Tertiary volcanics in the northern zone of the Eastern Pontides are characterized by subaerial and shallow-subaqueous facieses, and are divided into three volcanic suites: Eocene aged (1) basalt-trachybasalt-basaltic trachyandesite (BTB) and (2) trachyte-trachyandesite (TT), and Miocene aged (3) basanite-tephrite (BT) suites. Clinopyroxene is a common phase in all three volcanic suites, and has different compositions with Mg# varying from 0.57 to 0.91 in BTB suite and 0.57-0.84 in TT suite to 0.65-0.90 in BT suite. Feldspars in all suites generally exhibit wide range of compositions from sanidine to albite or anorthite and have weak normal and reverse compositional zoning. Olivines in BTB and BT suites have Fo60-92. Hornblendes in BTB, TT and BT suites are commonly magnesio-hastingsite and rare pargasite in composition (Mg#: 0.67-0.90). Brown mica is mainly phlogopite with Mg# ranging from 0.56 to 0.92 in the BTB suite, 0.59-0.84 in the TT suite, and 0.75-0.93 in the BT suite. Analcime is present only in the BT suite rocks. Fe-Ti oxides in all suites are mainly composed of magnetite and titanomagnetite. Textural petrographic and mineral chemical data suggest that magmas had undergone hydrous and anhydrous crystallizations in deep-, mid-, and shallow-crustal magma chambers. Clinopyroxene thermobarometric calculations show that Eocene magma chambers were characterized by temperature ranging from 1,100 to 1,244 °C and pressure ranging from 1.84 to 5.39 kbar. Similarly, the Miocene magma chambers were characterized by temperature ranging from 1,119 to 1,146 °C and pressure ranging from 4.23 to 4.93 kbar. Hornblende thermobarometry, oxygen fugacity, and hygrometer reveal that the crystallization temperature of Eocene volcanics range from 956 to 959 °C at pressure ranging from 6.49 to 6.52 kbar. Eocene volcanics were characterized by water content ranging from 7.83 to 8.57 wt.% and oxygen fugacity of 10-9.36 to 10-9.46 (ΔNNO+2). Miocene volcanics had crystallization

  3. Simultaneous inhibition of carbon and nitrogen mineralization in a forest soil by simulated acid precipitation

    SciTech Connect

    Klein, T.M.; Novick, N.J.; Kreitinger, J.P.; Alexander, M.

    1984-06-01

    One method to simulate the long-term exposure of soil to acid rain involves the addition of single doses of concentrated acid. The inhibition of carbon mineralization accompanied by a stimulation of nitrogen mineralization may result from this severe, unnatural treatment. The present study was designed to determine whether the inhibition of carbon mineralization and the accompanying enhanced nitrogen mineralization would occur when soils are treated with more dilute acid for long periods of time, as takes place in nature.

  4. Redgillite, Cu[subscript 6](OH)1 0(SO[subscript 4]).2H[subscript 2]O, a new mineral from Caldbeck Fells, Cumbria, England, UK: Description and crystal structure

    SciTech Connect

    Pluth, J.J.; Steele, I.M.; Kampf, A.R.; Green, D.I.

    2008-10-03

    Redgillite, Cu{sub 6}(OH){sub 10}(SO{sub 4}) {center_dot} H{sub 2}O, space group P2{sub 1}/c, a 3.155(3) {angstrom}, b 10.441(8) {angstrom}, c 19.436(16) {angstrom}, {beta} 90.089(13){sup o}, V = 640.2(9) {angstrom}{sup 3}, Z = 2, is a new mineral from Silver Gill, Caldbeck Fells, Cumbria, England. The strongest six lines of the X-ray powder-diffraction pattern [d in {angstrom}, (I) (hkl)] are: 9.72 (90) (002), 7.11 (100) (012), 4.60 (30) (022), 4.068 (20) (023), 2.880 (30) (112,11{bar 2}), 2.318 (50) (131,13{bar 1}). It occurs as translucent to transparent grass-green bladed crystals up to 0.15 mm long with squared-off or tapering terminations; usually in radiating groups. Forms observed are {l_brace}001{r_brace} prominent, {l_brace}010{r_brace} as composite stepped faces, and {l_brace}100{r_brace} irregular. Redgillite has white streak, vitreous lustre and Mohs hardness of {approx}2. Blades are slightly flexible with irregular fracture and exhibit a perfect {l_brace}001{r_brace} cleavage and good {l_brace}100{r_brace} and {l_brace}010{r_brace} cleavages. The measured density (by sink-float) is 3.45(5) g/cm{sup 3}; the calculated density is 3.450 g/cm{sup 3}. The mineral dissolves slowly in dilute HCl. Redgillite is biaxial-negative with {alpha} = 1.693(2), {beta} = 1.721(2), {gamma} = 1.723(2), 2V = 30(2){sup o} (meas.) and 30{sup o} (calc.); dispersion is r > v, medium; pleochroism: Y blue-green > X blue-green > Z yellow-green; orientation: X c, Y = b, Z a. Electron microprobe analyses yielded CuO 68.9, SO{sub 3} 11.6, total 80.5. With water inferred from the structure analysis, the empirical formula is: Cu{sub 5.995}(OH){sub 9.991}(SO{sub 4}){sub 1.003} {center_dot} H{sub 2}O. Redgillite is typically found in thin fractures in partly oxidized sulphides where it is commonly associated with langite and more rarely with malachite, cuprite, connellite and brochantite. The name is for the Red Gill mine, from which the mineral is best known. The crystal structure of

  5. Spatial distribution and compositional variation of APS minerals related to uranium deposits in the Kiggavik-Andrew Lake structural trend, Nunavut, Canada

    NASA Astrophysics Data System (ADS)

    Riegler, Thomas; Quirt, Dave; Beaufort, Daniel

    2016-02-01

    The Kiggavik-Andrew Lake structural trend consists of four mineralized zones, partially outcropping, lying 2 km south of the erosional contact with the unmetamorphosed sandstone and basal conglomerates of the Paleoproterozoic Thelon Formation. The mineralization is controlled by a major E-W fault system associated with illite and sudoite alteration halos developed in the Archean metagraywackes of the Woodburn Lake Group. Aluminum phosphate sulfate (APS) minerals from the alunite group crystallized in association with the clay minerals in the basement alteration halo as well as in the overlying sandstones, which underwent mostly diagenesis. APS minerals are Sr- and S-rich (svanbergite end-member) in the sedimentary cover overlying the unconformity, whereas they are light rare earth elements (LREE)-rich (florencite end-member) in the altered basement rocks below the unconformity. The geochemical signature of each group of APS minerals together with the petrography indicates three distinct generations of APS minerals related to the following: (1) paleoweathering of continental surfaces prior to the basin occurrence, (2) diagenetic processes during the burial history of the lower unit of the Thelon sandstones, and (3) hydrothermal alteration processes which accompanied the uranium deposition in the basement rocks and partially overlap the sedimentary-diagenetic mineral parageneses. In addition, the association of a first generation of APS minerals with both detrital cerium oxide and aluminum oxy-hydroxide highlights the fact that a part of the detrital material of the basal Thelon Formation originated from eroded paleolaterite (allochthonous regolith). The primary rare earth element (REE)-bearing minerals (e.g., monazite, REE carbonates, and allanite) of the host rocks were characterized to identify the potential sources of REE. The REE chemical composition highlights a local re-incorporation of the REE released from the alteration processes in the APS minerals of

  6. Near infrared detection of ammonium minerals.

    USGS Publications Warehouse

    Krohn, M.D.; Altaner, S.P.

    1987-01-01

    Diagnostic near-infrared spectral features have been identified for minerals with ammonium (NH4+) bound in the crystal structure. Near-infrared detection of NH4-bearing minerals may provide useful information for prospecting for certain ore deposits and may provide a better understanding of the nitrogen cycle within geologic environments.-from Authors

  7. Industrial Minerals

    ERIC Educational Resources Information Center

    Bradbury, James C.

    1978-01-01

    The past year is seen as not particularly good for industrial minerals and for industry in general. Environmental concerns continued to trouble the industry with unacceptable asbestos concentrations and chlorofluorocarbon effects on ozone. A halting U.S. economy also affected industrial progress. (MA)

  8. Crystal-structure analysis of four mineral samples of anhydrite, CaSO[subscript 4], using synchrotron high-resolution powder X-ray diffraction data

    SciTech Connect

    Antao, Sytle M.

    2014-05-28

    The crystal structures of four samples of anhydrite, CaSO{sub 4}, were obtained by Rietveld refinements using synchrotron high-resolution powder X-ray diffraction (HRPXRD) data and space group Amma. As an example, for one sample of anhydrite from Hants County, Nova Scotia, the unit-cell parameters are a = 7.00032(2), b = 6.99234(1), c = 6.24097(1) {angstrom}, and V = 305.487(1) {angstrom}{sup 3} with a > b. The eight-coordinated Ca atom has an average distance of 2.4667(4) {angstrom}. The tetrahedral SO{sub 4} group has two independent S-O distances of 1.484(1) to O1 and 1.478(1) {angstrom} to O2 and an average distance of 1.4810(5) {angstrom}. The three independent O-S-O angles [108.99(8) x 1, 110.38(3) x 4, 106.34(9){sup o} x 1; average [6] = 109.47(2){sup o}] and S-O distances indicate that the geometry of the SO{sub 4} group is quite distorted in anhydrite. The four anhydrite samples have structural trends where the a, b, and c unit-cell parameters increase linearly with increasing unit-cell volume, V, and their average and distances are nearly constant. The grand mean = 2.4660(2) {angstrom}, and grand mean = 1.4848(3) {angstrom}, the latter is longer than 1.480(1) {angstrom} in celestite, SrSO{sub 4}, as expected.

  9. The ACOSTA accompanying measure A2106.

    PubMed

    Thayer, C; De Moor, G; Van Goor, J

    1994-10-01

    At a time when the informatics and telecommunications industries are looking for new markets to exploit in relation, for example, to the emerging ISDN and broadband communications networks, there is a need to create a broad consensus in Europe by bringing together systematically the relevant industries including telecom service providers, health care providers, insurance organisations, standardisation experts and policy makers. The aim of the ACOSTA (Consensus Formation and Standardisation Promotion) Accompanying Measure is the creation of more general awareness of the relevant environment among all the parties, better specification of common requirements and options taking better account of the real needs of the users, and enlargement of the common market in health care telematics. PMID:7889758

  10. Sacral Perineural Cyst Accompanying Disc Herniation

    PubMed Central

    Ju, Chang Il; Shin, Ho; Kim, Hyeun Sung

    2009-01-01

    Although most of sacral perineural cysts are asymptomatic, some may produce symptoms. Specific radicular pain may be due to distortion, compression, or stretching of nerve root by a space occupying cyst. We report a rare case of S1 radiculopathy caused by sacral perineural cyst accompanying disc herniation. The patient underwent a microscopic discectomy at L5-S1 level. However, the patient's symptoms did not improved. The hypesthesia persisted, as did the right leg pain. Cyst-subarachnoid shunt was set to decompress nerve root and to equalize the cerebrospinal fluid pressure between the cephalad thecal sac and cyst. Immediately after surgery, the patient had no leg pain. After 6 months, the patient still remained free of leg pain. PMID:19352483

  11. Sacral perineural cyst accompanying disc herniation.

    PubMed

    Ju, Chang Il; Shin, Ho; Kim, Seok Won; Kim, Hyeun Sung

    2009-03-01

    Although most of sacral perineural cysts are asymptomatic, some may produce symptoms. Specific radicular pain may be due to distortion, compression, or stretching of nerve root by a space occupying cyst. We report a rare case of S1 radiculopathy caused by sacral perineural cyst accompanying disc herniation. The patient underwent a microscopic discectomy at L5-S1 level. However, the patient's symptoms did not improved. The hypesthesia persisted, as did the right leg pain. Cyst-subarachnoid shunt was set to decompress nerve root and to equalize the cerebrospinal fluid pressure between the cephalad thecal sac and cyst. Immediately after surgery, the patient had no leg pain. After 6 months, the patient still remained free of leg pain. PMID:19352483

  12. The Mechanism of Atomization Accompanying Solid Injection

    NASA Technical Reports Server (NTRS)

    Castleman, R A , Jr

    1933-01-01

    A brief historical and descriptive account of solid injection is followed by a detailed review of the available theoretical and experimental data that seem to throw light on the mechanism of this form of atomization. It is concluded that this evidence indicates that (1) the atomization accompanying solid injection occurs at the surface of the liquid after it issues as a solid stream from the orifice; and (2) that such atomization has a mechanism physically identical with the atomization which takes place in an air stream, both being due merely to the formation, at the gas-liquid interface, of fine ligaments under the influence of the relative motion of gas and liquid, and to their collapse, under the influence of surface tension, to form the drops in the spray.

  13. [How to accompany a suicidal patient].

    PubMed

    Dorfman Lerner, B

    1986-06-01

    In this paper the author offers the prospective T.C. an orientation for the treatment of patients who have intended suicide. After examining general questions such as who and when people commit suicide, she presents an "Assessment of self-destructive potentiality" by Tabachnik & Farberow as a guide to the best prevention of the suicidal act. The metapsychological view of Freud as regards the repressed homicidal motivation in suicide is complemented by the views of Garma and Abadi. In respect to the process of accompaniment in these cases, the author suggests the appearance of four phases (simultaneous or in succession) that are: 1. the presence and the regard in which what is important for the patient is that the T.C. is there and affectionately regards him; 2. the listening, in which the T.C. provides facilities for the patient to speak; 3. the key word, in which "I comprehend" is the privileged T.C. expression; and 4. the dialogue. Within phase 3. discrimination can be made between different psycholinguistic aspects of the key expression, such as: a) its constituting aspects; b) its catarctic or economic aspect; c) its meaning a recognition of the patient's identity; and d) the emergence of hope. Also, as suicide is the end point of different psychopathologies, a brief indication of possible T.C. responses is given. In all these, the principal aim is to help the patient to elaborate a new life project. A clinical successful example shows how three T.C. were included in the treatment of a suicidal patient to accompany her in the recognition and tolerance of her own and others' aggressive feelings. Some philosophical considerations are added. PMID:3788628

  14. Cystic lesions accompanying extra-axial tumours.

    PubMed

    Lohle, P N; Wurzer, H A; Seelen, P J; Kingma, L M; Go, K G

    1999-01-01

    We examined the mechanism of cyst formation in extra-axial tumours in the central nervous system (CNS). Cyst fluid, cerebrospinal fluid (CSF) and blood plasma were analysed in eight patients with nine peritumoral cysts: four with meningiomas, two with intracranial and two spinal intradural schwannomas. Measuring concentrations of various proteins [albumin, immunoglobulin G (IgG), IgA, alpha 2-macroglobulin and IgM] in cyst fluid, CSF and blood plasma provides insight into the state of the semipermeability of the blood-brain barrier (BBB) and blood-cerebrospinal fluid barrier. Peritumoral cysts accompanying intra-axial brain tumours are the end result of disruption of the BBB and oedema formation. Unlike intra-axial tumours which lie embedded within nervous tissue, extra-axial tumours tend to be separated from nervous tissue by arachnoid and pia mater. High concentrations of proteins were measured in the cyst fluid, approaching blood plasma levels, suggesting a local barrier disruption, and passage across the arachnoid, pia mater and cortical/medullary layer into the CNS parenchyma, leaving the protein concentrations of CSF practically unchanged. We confirmed that very high concentrations of protein are to be found in tumour cysts, plasma proteins forming almost 90% of the total protein in the cyst. We review current hypotheses on the pathogenesis of cysts accompanying neoplasms, particularly meningiomas and schwannomas, and conclude that the majority of proteins in cyst fluid in extra-axial, intradural meningiomas and schwannomas are plasma proteins. This provides a strong argument for pathogenesis of extra-axial intradural tumour cysts in favour of leakage of plasma proteins out of the tumour vessels into the nervous tissue. PMID:9987761

  15. Hole defects in the crystal structure of synthetic lipscombite (Fe{sub 4.7}{sup 3+}Fe{sub 2.3}{sup 2+})[PO{sub 4}]{sub 4}O{sub 2.7}(OH){sub 1.3} and genetic crystal chemistry of minerals of the lipscombite-barbosalite series

    SciTech Connect

    Yakubovich, O. V. Steele, I. M.; Rusakov, V. S.; Urusov, V. S.

    2006-05-15

    The crystal structure of a synthetic analog of the mineral lipscombite (Fe{sub 2.3}{sup 2+}Fe{sub 4.7}{sup 3+})[PO{sub 4}]{sub 4}O{sub 2.7}(OH){sub 1.3} obtained under hydrothermal conditions in the LiF-Fe{sub 2}O{sub 3}-(NH{sub 4}){sub 2}HPO{sub 4}-H{sub 2}O system is resolved (R = 0.040) by X-ray diffraction analysis (Bruker Smart diffractometer with a highly sensitive CCD detector, MoK{sub {alpha}} radiation): a = 14.776(3) A, b = 14.959(3) A, c = 7.394(1) A, {beta} = 119.188(4) deg., sp. gr. C2/c, Z = 4, {rho}{sub exp} = 3.8 g/cm{sup 3}, {rho}{sub calcd} = 3.9 g/cm{sup 3}. Fe{sup 2+} and Fe{sup 3+} cations are statistically distributed in each of four crystallographically independent positions, while occupying the corresponding octahedra with probabilities of 60, 90, 100, and 91%. The ratio Fe{sup 2+}/Fe{sup 3+} in the composition of the crystals was established by Moessbauer spectroscopy. Lipscombite is interpreted as a mineral of variable composition described by the formula (Fe{sub x}{sup 2+}Fe{sub n-x}{sup 3+})[PO{sub 4}]{sub 4}O{sub y}(OH){sub 4-y}. The field of stability is determined as a function of the iron content and the ratio Fe{sup 2+}/Fe{sup 3+}. It is shown that at n = 6 iron cations are ordered in octahedra and barbosalite structure is formed. An interpretation of genetically and structurally related members of the lipscombite family within a unified polysomatic series is proposed.

  16. Nevadaite, (Cu2+, Al, V3+)6 [Al8 (PO4)8 F8] (OH 2 (H2O)22, a new phosphate mineral species from the Gold Quarry mine, Carlin, Eureka County, Nevada: description and crystal structure

    USGS Publications Warehouse

    Cooper, M.A.; Hawthorne, F.C.; Roberts, Andrew C.; Foord, E.E.; Erd, Richard C.; Evans, H.T., Jr.; Jensen, M.C.

    2004-01-01

    Nevadaite, (Cu2+, ???, Al, V3+)6 (PO4)8 F8 (OH)2 (H2O)22, is a new supergene mineral species from the Gold Quarry mine, near Carlin, Eureka County, Nevada, U.S.A. Nevadaite forms radiating clusters to 1 mm of prismatic crystals, locally covering surfaces more that 2 cm across; individual crystals are elongate on [001] with a length:width ratio of > 10:1 and a maximum diameter of ???30 ??m. It also occurs as spherules and druses associated with colorless to purple-black fluellite, colorless wavellite, strengitevariscite, acicular maroon-to-red hewettite, and rare anatase, kazakhstanite, tinticite, leucophosphite, torbernite and tyuyamunite. Nevadaite is pale green to turquoise blue with a pale powder-blue streak and a vitreous luster; it does not fluoresce under ultra-violet light. It has no cleavage, a Mohs hardness of ???3, is brittle with a conchoidal fracture, and has measured and calculated densities of 2.54 and 2.55 g/cm3, respectively. Nevadaite is biaxial negative, with ?? 1.540, ?? 1.548, ?? 1.553, 2V(obs.) = 76??, 2V(calc.) = 76??, pleochroic with X pale greenish blue, Y very pale greenish blue, Z blue, and with absorption Z ??? X > Y and orientation X = c, Y = a, Z = b. Nevadaite is orthorhombic, space group P21mn, a 12.123(2), b 18.999(2), c 4.961(1) A?? , V 1142.8(2) A??3, Z = 1, a:b:c = 0.6391:1:0.2611. The strongest seven lines in the X-ray powder-diffraction pattern [d in A??(I)(hkl)] are: 6.077(10)(200), 5.618(9)(130), 9.535(8)(020), 2.983(6)(241), 3.430(4)(041), 2.661(4)(061 , and 1.844(4)(352). A chemical analysis with an electron microprobe gave P2O5 32.54, Al2O3 27.07, V2O3 4.24, Fe2O3 0.07, CuO 9.24, ZnO 0.11, F 9.22, H2O (calc.) 23.48, OH ??? F -3.88, sum 102.09 wt.%; the valence states of V and Fe, and the amount of H2O, were determined by crystal-structure analysis. The resulting empirical formula on the basis of 63.65 anions (including 21.65 H2O pfu) is (CU2+2.00 Zn0.02 V3+0.98 Fe3+0.01 Al1.15)??4.16 Al8 P7.90 O32 [F8.37 (OH 1.63]??10 (H2O

  17. Occurrence of Sulphides in Sowia Dolina Near Karpacz (SW Poland) - An Example of ore Mineralization in the Contact Aureole of the Karkonosze Granite

    NASA Astrophysics Data System (ADS)

    Mochnacka, Ksenia; Oberc-Dziedzic, Teresa; Mayer, Wojciech; Pieczka, Adam; Góralski, Michał

    2007-01-01

    The authors studied the poorly-known, uneconomic sulphide mineralization site in Sowia Dolina near Karpacz. Host rocks are hornfelses of the Velká Úpa schist series, which belongs to the Izera-Kowary Unit. Ore minerals assemblage includes: pyrrhotite, pyrite, chalcopyrite, arsenopyrite, sphalerite, galena and marcasite, accompanied by ilmenite and rutile. The oldest sulphide is high-temperature pyrrhotite crystallized at about 600°C, which is in good agreement with the temperature range of contact metamorphic conditions, revealed by muscovitesillimanite transformation. Low-temperature pyrrhotite and other sulphides formed at about 390°C (arsenopyrite geothermometer) down to 265°C (pyrrhotite geothermometer), whereas fluid inclusions studies of vein quartz demonstrated the temperature range 380-150°C. Mineralization in Sowia Dolina is similar to other ore hydrothermal deposits known from the proximal or distal contact zone of the Karkonosze granite.

  18. 30 CFR 250.251 - If I propose activities in the Alaska OCS Region, what planning information must accompany the DPP?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 2 2011-07-01 2011-07-01 false If I propose activities in the Alaska OCS Region, what planning information must accompany the DPP? 250.251 Section 250.251 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, REGULATION, AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE...

  19. 30 CFR 250.220 - If I propose activities in the Alaska OCS Region, what planning information must accompany the EP?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 2 2011-07-01 2011-07-01 false If I propose activities in the Alaska OCS Region, what planning information must accompany the EP? 250.220 Section 250.220 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, REGULATION, AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE...

  20. Hanawaltite, Hg1+6Hg2+[Cl,(OH)]2O3 - A new mineral from the Clear Creek claim, San Benito County, California: Description and crystal structure

    USGS Publications Warehouse

    Roberts, Andrew C.; Grice, Joel D.; Gault, Robert A.; Criddle, A.J.; Erd, Richard C.

    1996-01-01

    Hanawaltite, ideally Hg1+6Hg2+O3Cl2, is orthorhombic, Pbma (57), with unit-cell parameters refined from powder data: a=11.790(3), b=13.881(4), c=6.450(2) A??, V=1055.7(6) A??3, a:b:c =0.8494:1:0.4647, Z=4. The strongest six lines of the X-ray powder-diffraction pattern [d in A?? (I)(hkl)] are: 5.25 (80)(111), 3.164 (60)(231), 3.053 (100)(041), 2.954 (70)(141), 2.681 (50)(401), and 2.411 (50)(232,341). The mineral is an extremely rare constituent in a small prospect pit near the long-abandoned Clear Creek mercury mine, New Idria district, San Benito County, California. It was found on a single-fracture surface where it is intimately associated with calomel, native mercury, cinnabar, montroydite, and quartz. Individual crystals are subhedral to anhedral, platy to somewhat bladed, and average about 50 ??m in longest dimension. The largest known crystal is approximately 0.3??0.3 mm in size and is striated parallel [001]. Hanawaltite is opaque to translucent (on very thin edges), black to very dark brown-black in color, with a black to dark red-brown streak. Other physical properties include: metallic luster; cleavage {001} good; uneven fracture; brittle; nonfluorescent; H<5; calculated density (for the empirical formula) 9.51 g/cm3. In polished section, hanawaltite is moderately to strongly bireflectant and is pleochroic white (R1) to blue-white (R2). In reflected plane-polarized light, it is white with orange-red internal reflections in very thin grains and at grain margins. The anisotropy is strong with bright metallic blue rotation tints. Measured reflectance values, in air and in oil, are tabulated. Electron-microprobe analysis yielded Hg2O 82.46, HgO 14.27, Cl 3.33, H2O [0.34], sum [100.40], less O=Cl 0.75, total [99.65] wt. %, corresponding to Hg1+6.00H2+1.00[Cl 1.43(OH)0.57]??2.00O3.00, based on O+C1=5. After the crystal structure was determined, the original microprobe value for Hg2O, 96.2, was partitioned in a ratio of 6Hg2O:HgO and (OH) was calculated, such

  1. Mineral bioprocessing

    SciTech Connect

    Torma, A.E.

    1993-05-01

    In the last 25 years, the introduction of biotechnological methods in hydrometallurgy has created new opportunities and challenges for the mineral processing industry. This was especially true for the production of metal values from mining wastes and low-and-complex-grade mineral resources, which were considered economically not amenable for processing by conventional extraction methods. Using bio-assisted heap, dump and in-situ leaching technologies, copper and uranium extractions gained their first industrial applications. The precious metal industries were the next to adopt the bio-preoxidation technique in the extraction of gold from refractory sulfide-bearing ores and concentrates. A variety of other bioleaching opportunities exist for nickel, cobalt, cadmium and zinc sulfide leaching. Recently developed bioremediation methods and biosorption technologies have shown a good potential for industrial applications to remove trace heavy metal and radionuclide concentrations from contaminated soils, and mining and processing effluents.

  2. The Use of Backscattered Electron Imaging and Transmission Electron Microscopy to Assess Bone Architecture and Mineral Loci: Effect of Intermittent Slow-Release Sodium Fluoride Therapy

    NASA Astrophysics Data System (ADS)

    Zerwekh, Joseph E.; Bellotto, Dennis; Prostak, Kenneth S.; Hagler, Herbert K.; Pak, Charles Y. C.

    1996-04-01

    Backscattered electron imaging (BEI) and transmission electron microscopy (TEM) were used to examine the effects of treatment with intermittent slow-release sodium fluoride (SRNaF) and continuous calcium citrate on bone architecture and crystallinity. Examination was performed in nondecalcified biopsies obtained from patients following up to four years of therapy (placebo or SRNaF) and compared to pretreatment biopsies from each patient, as well as to bone from young, normal subjects. BEI images disclosed increased areas of recent bone formation following fluoride administration. There was no evidence of a mineralization defect in any biopsy and both cortical and trabecular architecture remained normal. TEM analysis demonstrated intrafibrillar platelike crystals and extrafibrillar needlelike crystals for both the pre- and post-treatment biopsies as well as for the bone from young normal subjects. There was no evidence of increased crystal size or of an increase in extrafibrillar mineral deposition. These observations suggest that intermittent SRNaF and continuous calcium therapy exerts an anabolic action on the skeleton not accompanied by a mineralization defect or an alteration of bone mineral deposition. The use of BEI and TEM holds promise for the study of the pathophysiology and treatment of metabolic bone diseases.

  3. Mechanical Surface Waves Accompany Action Potential Propagation

    NASA Astrophysics Data System (ADS)

    Machta, Benjamin; El Hady, Ahmed

    2015-03-01

    The action potential (AP) is the basic mechanism by which information is transmitted along neuronal axons. Although the excitable nature of axons is understood to be primarily electrical, many experimental studies have shown that a mechanical displacement of the axonal membrane co-propagates with the electrical signal. While the experimental evidence for co-propagating mechanical waves is diverse and compelling, there is no consensus for their physical underpinnings. We present a model in which these mechanical displacements arise from the driving of mechanical surface waves, in which potential energy is stored in elastic deformations of the neuronal membrane and cytoskeleton while kinetic energy is stored in the movement of the axoplasmic fluid. In our model these surface waves are driven by the traveling wave of electrical depolarization that characterizes the AP, altering the electrostatic forces across the membrane as it passes. Our model allows us to predict the shape of the displacement that should accompany any traveling wave of voltage, including the well-characterized AP. We expect our model to serve as a framework for understanding the physical origins and possible functional roles of these AWs in neurobiology. See Arxiv/1407.7600

  4. 30 CFR 550.247 - What biological, physical, and socioeconomic information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 2 2013-07-01 2013-07-01 false What biological, physical, and socioeconomic... Operations Coordination Documents (docd) § 550.247 What biological, physical, and socioeconomic information... Regional Supervisor, as accompanying information: (a) Biological environment reports....

  5. 30 CFR 550.247 - What biological, physical, and socioeconomic information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 2 2014-07-01 2014-07-01 false What biological, physical, and socioeconomic... Operations Coordination Documents (docd) § 550.247 What biological, physical, and socioeconomic information... Regional Supervisor, as accompanying information: (a) Biological environment reports....

  6. 30 CFR 550.247 - What biological, physical, and socioeconomic information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 2 2012-07-01 2012-07-01 false What biological, physical, and socioeconomic... Operations Coordination Documents (docd) § 550.247 What biological, physical, and socioeconomic information... Regional Supervisor, as accompanying information: (a) Biological environment reports....

  7. 30 CFR 250.247 - What biological, physical, and socioeconomic information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What biological, physical, and socioeconomic... Operations Coordination Documents (docd) § 250.247 What biological, physical, and socioeconomic information... Regional Supervisor, as accompanying information: (a) Biological environment reports....

  8. 30 CFR 250.247 - What biological, physical, and socioeconomic information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 2 2011-07-01 2011-07-01 false What biological, physical, and socioeconomic... (dpp) and Development Operations Coordination Documents (docd) § 250.247 What biological, physical, and... submitted it to the Regional Supervisor, as accompanying information: (a) Biological environment...

  9. 30 CFR 250.245 - What hydrogen sulfide (H2S) information must accompany the DPP or DOCD?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... analysis must be consistent with the EPA's risk management plan methodologies outlined in 40 CFR part 68. ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What hydrogen sulfide (H2S) information must... Documents (docd) § 250.245 What hydrogen sulfide (H2S) information must accompany the DPP or DOCD?...

  10. MicroRNA 224 Regulates Ion Transporter Expression in Ameloblasts To Coordinate Enamel Mineralization

    PubMed Central

    Fan, Yi; Zhou, Yachuan; Zhou, Xuedong; Sun, Feifei; Gao, Bo; Wan, Mian; Zhou, Xin; Sun, Jianxun; Xu, Xin; Cheng, Lei; Crane, Janet

    2015-01-01

    Enamel mineralization is accompanied by the release of protons into the extracellular matrix, which is buffered to regulate the pH value in the local microenvironment. The present study aimed to investigate the role of microRNA 224 (miR-224) as a regulator of SLC4A4 and CFTR, encoding the key buffering ion transporters, in modulating enamel mineralization. miR-224 was significantly downregulated as ameloblasts differentiated, in parallel with upregulation of SLC4A4 and CFTR. Overexpression of miR-224 downregulated SLC4A4 and CFTR expression in cultured human epithelial cells. A microRNA luciferase assay confirmed the specific binding of miR-224 to the 3′ untranslated regions (UTRs) of SLC4A4 and CFTR mRNAs, thereby inhibiting protein translation. miR-224 agomir injection in mouse neonatal incisors resulted in normal enamel length and thickness, but with disturbed organization of the prism structure and deficient crystal growth. Moreover, the enamel Ca/P ratio and microhardness were markedly reduced after miR-224 agomir administration. These results demonstrate that miR-224 plays a pivotal role in fine tuning enamel mineralization by modulating SLC4A4 and CFTR to maintain pH homeostasis and support enamel mineralization. PMID:26055330

  11. MicroRNA 224 Regulates Ion Transporter Expression in Ameloblasts To Coordinate Enamel Mineralization.

    PubMed

    Fan, Yi; Zhou, Yachuan; Zhou, Xuedong; Sun, Feifei; Gao, Bo; Wan, Mian; Zhou, Xin; Sun, Jianxun; Xu, Xin; Cheng, Lei; Crane, Janet; Zheng, Liwei

    2015-08-01

    Enamel mineralization is accompanied by the release of protons into the extracellular matrix, which is buffered to regulate the pH value in the local microenvironment. The present study aimed to investigate the role of microRNA 224 (miR-224) as a regulator of SLC4A4 and CFTR, encoding the key buffering ion transporters, in modulating enamel mineralization. miR-224 was significantly downregulated as ameloblasts differentiated, in parallel with upregulation of SLC4A4 and CFTR. Overexpression of miR-224 downregulated SLC4A4 and CFTR expression in cultured human epithelial cells. A microRNA luciferase assay confirmed the specific binding of miR-224 to the 3' untranslated regions (UTRs) of SLC4A4 and CFTR mRNAs, thereby inhibiting protein translation. miR-224 agomir injection in mouse neonatal incisors resulted in normal enamel length and thickness, but with disturbed organization of the prism structure and deficient crystal growth. Moreover, the enamel Ca/P ratio and microhardness were markedly reduced after miR-224 agomir administration. These results demonstrate that miR-224 plays a pivotal role in fine tuning enamel mineralization by modulating SLC4A4 and CFTR to maintain pH homeostasis and support enamel mineralization. PMID:26055330

  12. Mineral induction by immobilized phosphoproteins

    NASA Technical Reports Server (NTRS)

    Saito, T.; Arsenault, A. L.; Yamauchi, M.; Kuboki, Y.; Crenshaw, M. A.

    1997-01-01

    Dentin phosphoproteins are thought to have a primary role in the deposition of mineral on the collagen of dentin. In this study we determined the type of binding between collagen and phosphoproteins necessary for mineral formation onto collagen fibrils and whether the phosphate esters are required. Bovine dentin phosphophoryn or phosvitin from egg yolk were immobilized on reconstituted skin type I collagen fibrils by adsorption or by covalent cross-linking. In some samples the ester phosphate was removed from the covalently cross-linked phosphoproteins by treatment with acid phosphatase. All samples were incubated at 37 degrees C in metastable solutions that do not spontaneously precipitate. Reconstituted collagen fibrils alone did not induce mineral formation. The phosphoproteins adsorbed to the collagen fibrils desorbed when the mineralization medium was added, and mineral was not induced. The mineral induced by the cross-linked phosphoproteins was apatite, and the crystals were confined to the surface of the collagen fibrils. With decreasing medium saturation the time required for mineral induction increased. The interfacial tensions calculated for apatite formation by either phosphoprotein cross-linked to collagen were about the same as that for phosphatidic acid liposomes and hydroxyapatite. This similarity in values indicates that the nucleation potential of these highly phosphorylated surfaces is about the same. It is concluded that phosphoproteins must be irreversibly bound to collagen fibrils for the mineralization of the collagen network in solutions that do not spontaneously precipitate. The phosphate esters of phosphoproteins are required for mineral induction, and the carboxylate groups are not sufficient.

  13. Vitamins and Minerals

    MedlinePlus

    ... I Help a Friend Who Cuts? Vitamins and Minerals KidsHealth > For Teens > Vitamins and Minerals Print A ... of a good thing? What Are Vitamins and Minerals? Vitamins and minerals make people's bodies work properly. ...

  14. Crystal structure and genesis of the hydrated analog of rastsvetaevite

    NASA Astrophysics Data System (ADS)

    Rastsvetaeva, R. K.; Aksenov, S. M.; Rozenberg, K. A.

    2015-11-01

    The crystal structure of the hydrated analog of the mineral rastsvetaevite (tentatively called "hydrorastsvetaevite"), which was found by A.P. Khomyakov in ultraagpaitic pegmatites at the Rasvumchorr Mountain of the Khibiny alkaline massif (Kola Peninsula), has been determined by single crystal X-ray diffraction. The trigonal unit-cell parameters are as follows: a = 14.2812(2) Å, c = 60.533(5) Å, V = 10691.54(3) Å3, sp. gr. R3 m. The structure was refined to R = 5.9% in the isotropic and anisotropic approximation of atomic displacement parameters based on 2068 ref lections with | F| > 3σ( F). "Hydrorastsvetaevite" is on the whole analogous to other 24-layer representatives of the eudialyte group (called "megaeudialytes"), but is characterized by a high potassium content and is distinguished from other potassium-rich minerals (rastsvetaevite, davinciite, and andrianovite) by low sodium and alkaline-earth metal content, as well as by a high degree of hydration accompanied by the insertion of H3O groups, which partially or completely replace large cations. The idealized formula of "hydrorastsvetaevite" ( Z = 3) is (Na11(H3O)11K6(H2O)1.5Sr)Ca12Fe3Na2MnZr6Si52O144(OH)4.5Cl3.5(H2O)0.5. In alkaline pegmatites, "hydrorastsvetaevite" occurs as a secondary mineral developed from the original rastsvetaevite through decationation and hydration. The characteristic features of the genesis of eudialyte-group minerals containing potassium as a species-forming cation are discussed in terms of the concept of transformational mineral species. an]Mis||Original Russian Text R.K. Rastsvetaeva, S.M. Aksenov, K.A. Rozenberg, 2015, published in Kristallografiya, 2015, Vol. 60, No. 6, pp. 897-905.

  15. Fertility reduction programmes should accompany land reforms.

    PubMed

    Atiku, J

    1994-01-01

    health and welfare. Fertility reduction programs should be accompanied by economic policies, such as land reform. Uganda's proposed policy promotes intervention programs in health, nutrition, education, and the environment. To succeed, local support must be mobilized, and population problems should be addressed in a way that integrates gender equity, empowerment of women, sustained economic growth, eradication of poverty, and international cooperation. PMID:12318956

  16. Crystallization from Gels

    NASA Astrophysics Data System (ADS)

    Narayana Kalkura, S.; Natarajan, Subramanian

    Among the various crystallization techniques, crystallization in gels has found wide applications in the fields of biomineralization and macromolecular crystallization in addition to crystallizing materials having nonlinear optical, ferroelectric, ferromagnetic, and other properties. Furthermore, by using this method it is possible to grow single crystals with very high perfection that are difficult to grow by other techniques. The gel method of crystallization provides an ideal technique to study crystal deposition diseases, which could lead to better understanding of their etiology. This chapter focuses on crystallization in gels of compounds that are responsible for crystal deposition diseases. The introduction is followed by a description of the various gels used, the mechanism of gelling, and the fascinating phenomenon of Liesegang ring formation, along with various gel growth techniques. The importance and scope of study on crystal deposition diseases and the need for crystal growth experiments using gel media are stressed. The various crystal deposition diseases, viz. (1) urolithiasis, (2) gout or arthritis, (3) cholelithiasis and atherosclerosis, and (4) pancreatitis and details regarding the constituents of the crystal deposits responsible for the pathological mineralization are discussed. Brief accounts of the theories of the formation of urinary stones and gallstones and the role of trace elements in urinary stone formation are also given. The crystallization in gels of (1) the urinary stone constituents, viz. calcium oxalate, calcium phosphates, uric acid, cystine, etc., (2) the constituents of the gallstones, viz. cholesterol, calcium carbonate, etc., (3) the major constituent of the pancreatic calculi, viz., calcium carbonate, and (4) cholic acid, a steroidal hormone are presented. The effect of various organic and inorganic ions, trace elements, and extracts from cereals, herbs, and fruits on the crystallization of major urinary stone and gallstone

  17. Elastic Properties of Mantle Minerals

    NASA Astrophysics Data System (ADS)

    Duffy, T. S.; Stan, C. V.

    2012-12-01

    The most direct information about the interior structure of the Earth comes from seismic wave velocities. Interpretation of seismic data requires an understanding of how sound velocities and elastic properties of minerals vary with pressure, temperature, crystal structure, and composition as well as the role of anelasticity, melts, etc. More generally, elastic moduli are important for understanding many solid-state phenomena including mechanical stability, interatomic interactions, material strength, compressibility, and phase transition mechanisms. The database of mineral elasticity measurements has been growing rapidly in recent years. In this work, we report initial results of an ongoing survey of our current knowledge of mineral elasticity at both ambient conditions and high pressures and temperatures. The analysis is selective, emphasizing single crystal measurements but also incorporating polycrystalline measurements and volume compression data as appropriate. The goal is to synthesize our current understanding of mineral elasticity in terms of structure and composition, and to identify the major remaining needs for experimental and theoretical work. Clinopyroxenes (Cpx) provide an example of our approach. A wide range of clinopyroxene compositions are found geologically and Mg-, Ca-, and Na-rich clinopyroxenes are expected to be important components in the upper mantle. The single-crystal elastic properties of a number of endmember Cpx compositions have been measured and these exhibit a range of ~25% in shear velocity. Those with monovalent cations (spodumene, jadeite) in the M2 site exhibit the highest velocities while Fe-rich (hendenbergit, acmite) compositions have the lowest velocities. The effects on velocity due to a wide range of chemical substitutions can be defined, but there are important discrepancies and omissions in the database. New measurements of omphacites, intermediate diopside-hedenbergite compositions, aegerine/acmite, augite, etc. are

  18. Boron isotopic compositions of some boron minerals

    NASA Astrophysics Data System (ADS)

    Oi, Takao; Nomura, Masao; Musashi, Masaaki; Ossaka, Tomoko; Okamoto, Makoto; Kakihana, Hidetake

    1989-12-01

    Boron minerals that have different structural formulae but are supposed to have the same geologic origin have been collected and analyzed for the 11B /10B isotopic ratio. It has been reconfirmed that minerals of marine origin have higher 11B /10B ratios than those of nonmarine origin. It has been found that the sequence of decreasing 11B /10B values among the minerals with the same geologic origin is; borax, tincal, kernite (Na borates) > ulexite ( Na/Ca borate) > colemanite, iyoite, meyerhofferite (Ca borates). This sequence is explainable on the basis of the difference in crystal structure among the minerals. That is, minerals with higher BO 3/BO 4 ratios, (the ratio of the number of the BO 3 triangle units to the number of the BO 4 tetrahedron units in the structural formula of a mineral) have higher 11B /10B ratios.

  19. Mineral of the month: garnet

    USGS Publications Warehouse

    Olson, Donald

    2005-01-01

    Garnet is the general name given to a group of complex silicate minerals, all with isometric crystal structure, similar properties and chemical compositions. Garnet occurs in every color of the spectrum except blue, but it is most commonly red, purple, brown and green. Garnet necklaces dating from the Bronze Age have been found in graves and also among the ornaments adorning the oldest Egyptian mummies.

  20. Metallogeny of precious and base metal mineralization in the Murchison Greenstone Belt, South Africa: indications from U-Pb and Pb-Pb geochronology

    NASA Astrophysics Data System (ADS)

    Jaguin, J.; Poujol, M.; Boulvais, P.; Robb, L. J.; Paquette, J. L.

    2012-10-01

    The 3.09 to 2.97 Ga Murchison Greenstone Belt is an important metallotect in the northern Kaapvaal Craton (South Africa), hosting several precious and base metal deposits. Central to the metallotect is the Antimony Line, striking ENE for over 35 km, which hosts a series of structurally controlled Sb-Au deposits. To the north of the Antimony Line, hosted within felsic volcanic rocks, is the Copper-Zinc Line where a series of small, ca. 2.97 Ga Cu-Zn volcanogenic massive sulfide (VMS)-type deposits occur. New data are provided for the Malati Pump gold mine, located at the eastern end of the Antimony Line. Crystallizations of a granodiorite in the Malati Pump Mine and of the Baderoukwe granodiorite are dated at 2,964 ± 7 and 2,970 ± 7 Ma, respectively (zircon U-Pb), while pyrite associated with gold mineralization yielded a Pb-Pb age of 2,967 ± 48 Ma. Therefore, granodiorite emplacement, sulfide mineral deposition and gold mineralization all happened at ca. 2.97 Ga. It is, thus, suggested that the major styles of orogenic Au-Sb and the Cu-Zn VMS mineralization in the Murchison Greenstone Belt are contemporaneous and that the formation of meso- to epithermal Au-Sb mineralization at fairly shallow levels was accompanied by submarine extrusion of felsic volcanic rocks to form associated Cu-Zn VMS mineralization.

  1. The American Museum of Natural History Mineral Library for Spectroscopic Standards

    NASA Astrophysics Data System (ADS)

    Nissinboim, A.; Ebel, D. S.; Harlow, G. E.; Boesenberg, J. S.; Sherman, K. M.; Lewis, E. R.; Brusentsova, T. N.; Peale, R. E.; Lisse, C. M.; Hibbitts, C. A.

    2010-03-01

    Minerals from the AMNH collections are highly characterized (crystal XRD, EMPA), powdered <2 µm, reanalyzed (SEM, powder XRD), and transmission IR spectra analyzed for Herschel PACS. Library minerals will also serve reflectance spectra needs.

  2. Phase Transition Mechanisms in the Mineral Titanite CaTiOSiO4 Under High Pressure - a X-ray Single Crystal Study Between 7 GPa and 10 GPa

    NASA Astrophysics Data System (ADS)

    Rath, S.; Kunz, M.; Miletich, R.

    2001-12-01

    The monoclinic mineral titanite is a common accessory in many acid and intermediate igneous rock, gneises, mica shists and amphiboles. The structure of titanite is characterized by corner-linked chains of TiO6 -octahedra parallel to [100] connected via isolated SiO4 -tetrahedra. CaO7 polyhedra build chains along [101]. The octahedral Ti atoms show typical out-of-center distortions. Its behavior under high pressure can give information about the driving forces of the phase transition in ABOCO4 silicates. The behavior of titanite under high pressure has been studied up to 7 GPa and 850oK with powder diffraction, respectively [1], [2], [3] and several phase transitions were found. The structure remains monoclinic but changes from P21/a to A2/a at 3.6 GPa. Here we present evidence for a new A2/a P-1 phase transition at 10.5 GPa. At this pressure the cell metric decreased to the following values: a= 6.829(4) Å , b= 8.594(2) Å , c= 6.352(1) Å, α = 90.18(2)° , β = 112.78(2)° , γ = 89.70(2)° and V= 343.7(2) Å3. Structure refinement results of high-pressure X-ray single crystal studies at pressures from 7 to 10 GPa will be presented. In addition, we compare the titanite results to the phase transition in the topological identical malayaite CaSnSiO_4 at 5 GPa, where a similar phase transition has previously been observed [4]. [1] Angel, R.J.; Kunz, M.; Miletich, R.; Woodland, A.B.; Koch, M. and Xirouchakis, D. (1999); High-pressure phase transition in CaTiOSiO_4 titanite; Phase Transitions, 68, 533 - 543 [2] Bismayer, U.; Zhang, M.; Groat, L.A.; Salje, E.K.H and Meyer, H.-W. (1999); The \\beta - \\gamma Phase Transition in Titanite and the Isosymmetric Analogue in Malayaite; Phase Transitions, 68, 545 - 556 [3] Kunz, M., Arlt, T. and Stolz, J. (2000): In situ powder diffraction of titanite (CaTiSiO_4) at high pressure and high temperature, American Mineralogist, 85, 1465 - 1473 [4] Rath, St, Kunz, M. and Miletich, R. (2001) Pressure induced phase transition in

  3. Influence of the mineral staggering on the elastic properties of the mineralized collagen fibril in lamellar bone.

    PubMed

    Vercher-Martínez, Ana; Giner, Eugenio; Arango, Camila; Fuenmayor, F Javier

    2015-02-01

    In this work, a three-dimensional finite element model of the staggered distribution of the mineral within the mineralized collagen fibril has been developed to characterize the lamellar bone elastic behavior at the sub-micro length scale. Minerals have been assumed to be embedded in a collagen matrix, and different degrees of mineralization have been considered allowing the growth of platelet-shaped minerals both in the axial and the transverse directions of the fibril, through the variation of the lateral space between platelets. We provide numerical values and trends for all the elastic constants of the mineralized collagen fibril as a function of the volume fraction of mineral. In our results, we verify the high influence of the mineral overlapping on the mechanical response of the fibril and we highlight that the lateral distance between crystals is relevant to the mechanical behavior of the fibril and not only the mineral overlapping in the axial direction. PMID:25498297

  4. New Minerals and Science.

    ERIC Educational Resources Information Center

    Birch, William D.

    1997-01-01

    Defines geodiversity, compares it to biodiversity, and discusses the mineral classification system. Charts the discovery of new minerals in Australia over time and focuses on uses of these minerals in technological advances. (DDR)

  5. Mineral spirits poisoning

    MedlinePlus

    Mineral spirits are liquid chemicals used to thin paint and as a degreaser. Mineral spirits poisoning occurs ... be found in: Mineral spirits ( Stoddard solvent ) Some paints Some floor and furniture waxes and polishes Some ...

  6. 19 CFR 12.6 - Affidavits required to accompany entry.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Section 12.6 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY... required to accompany entry. (a) Cheeses produced in the member states of the European Communities shall... not be required to accompany importations of cheese produced in the member states of the...

  7. 9 CFR 93.409 - Articles accompanying ruminants.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Articles accompanying ruminants. 93...; REQUIREMENTS FOR MEANS OF CONVEYANCE AND SHIPPING CONTAINERS Ruminants § 93.409 Articles accompanying ruminants..., blankets, or other things used for or about ruminants governed by the regulations in this part, shall...

  8. 9 CFR 93.409 - Articles accompanying ruminants.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Articles accompanying ruminants. 93...; REQUIREMENTS FOR MEANS OF CONVEYANCE AND SHIPPING CONTAINERS Ruminants § 93.409 Articles accompanying ruminants..., blankets, or other things used for or about ruminants governed by the regulations in this part, shall...

  9. 9 CFR 93.409 - Articles accompanying ruminants.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Articles accompanying ruminants. 93...; REQUIREMENTS FOR MEANS OF CONVEYANCE AND SHIPPING CONTAINERS Ruminants § 93.409 Articles accompanying ruminants..., blankets, or other things used for or about ruminants governed by the regulations in this part, shall...

  10. 9 CFR 93.409 - Articles accompanying ruminants.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Articles accompanying ruminants. 93...; REQUIREMENTS FOR MEANS OF CONVEYANCE AND SHIPPING CONTAINERS Ruminants § 93.409 Articles accompanying ruminants..., blankets, or other things used for or about ruminants governed by the regulations in this part, shall...