Chemical Characterisation of the USGS Reference Glasses GSA-1G, GSC-1G, GSD-1G, GSE-1G, BCR-2G, BHVO-2G and BIR-1G Using EPMA, ID-TIMS, ID-ICP-MS and LA-ICP-MS   总被引：6，自引：2，他引：6  

Klaus Peter Jochum  Matthias Willbold  Ingrid Raczek  Brigitte Stoll  Kirstin Herwig 《Geostandards and Geoanalytical Research》2005,29(3):285-302

The USGS reference glasses GSA-1G, GSC-1G, GSD-1G, GSE-1G, BCR-2G, BHVO-2G and BIR-1G were investigated by different analytical techniques. All these materials have a geological (basaltic) matrix and are therefore useful in igneous geochemistry as matrix-matched reference materials for microanalytical techniques. The new GS glasses have trace elements in groups at concentration levels of about < 0.01, 5, 50 and 500 μg g^-1. Their major element compositions have been determined by EPMA, and trace elements have been analysed by LA-ICP-MS and two isotope dilution techniques using TIMS and ICP-MS. EPMA and LA-ICP-MS analyses indicated that the USGS reference glasses are homogeneous at the μm to mm scale with respect to major (variations < 1-2%) and most trace elements (variations 1-4%). Trace element data obtained from the different analytical techniques agreed within an uncertainty of 1-5%, indicating that between method results are comparable. Therefore, the preliminary working values for the four USGS GS glasses calculated from these data have a low level of uncertainty.  相似文献   

Refractory organic carbon in particle-size fractions of arable soils II: organic carbon in relation to mineral surface area and iron oxides in fractions <6 μm     

Rita Kiem  Ingrid Kgel-Knabner 《Organic Geochemistry》2002,33(12):434

The interaction of organic compounds with the mineral phase is considered as one stabilization mechanism for organic carbon (OC) in soils. The objective of this study is to assess the role of mineral surfaces for the long-term stabilization of OC in arable soils, with special emphasis on iron oxides. Soil samples were taken from two contrasting treatment types, i.e. fertilized plots and C-depleted plots, in long-term agroecosystem experiments. The soil organic carbon pool of the C-depleted plots is considered to show a lower contribution of labile compounds and consequently to be relatively enriched in refractory compounds compared with the fertilized counterparts. In fractions <6 μm, OC was studied in relation to total mineral surface area, surface area contributed by oxides and silicates, and the content and type of iron oxides (dithionite and oxalate extractable iron, Fe_d and Fe_o). In two sandy soils, OC contents were linearly related to total mineral surface area and the content of the two iron oxide fractions (Fe_d and Fe_o). The surface area developed by the silicates was low and thus the surface area contribution from oxides was dominant in fractions <6 μm. In contrast to the sandy soils, in a loamy soil OC was not correlated with surface area or the iron oxide content. However, the different soils agreed with respect to the behavior of C in density fractions: losses of OC occurred mainly from the light fraction (2 g cm⁻³), whereas C in the heavy fraction (>2 g cm⁻³) proved to be stable. For the sandy soils, mineral surface area appears to control the storage of OC in fine fractions. Given the dominant surface area contribution from oxides, OC storage here primarily depends on the oxides. The C-depleted plots in particular show that surface area controls the accumulation of refractory C. The interaction of organic compounds with the mineral phase, mainly with the surface of oxides, seems to be a major mechanism for the long-term stabilization of OC in these sandy soils. An interaction with minerals seems to be important for stabilizing OC also in the loamy soil, although this is not reflected by a proportional relation between OC and surface area across the fractions.  相似文献   

Hydraulic properties of the crystalline basement     

Ingrid Stober  Kurt Bucher 《Hydrogeology Journal》2007,15(8):1643-1643

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Influence of advection on scales of ecological studies in a coastal equilibrium flow     

Ingrid Hillmer  Jörg Imberger 《Continental Shelf Research》2007

Spatial patterns are generated as a result of the coupling between biogeochemical and physical processes and the ability to capture and reproduce patchiness is crucial for the better comprehension of an ecosystem and its response to external perturbations. A 1D reaction–diffusion–advection equation is used to investigate the formation of patterns and relevant time and spatial scales and thus define an approach for the determination of a critical domain size that allows differentiation of the role of local and internal cycling from advective fluxes across the open boundaries in a shallow coastal ecosystem. By using a 3D numerical model, in conjunction with an extensive field data set, it is shown that domain sizes must be larger than this critical value in order to capture the patterns generated within the system. For smaller domains, the evolution of the system is controlled by transport processes across the boundaries misleading the interpretation of the internal ecological dynamics. The study of the influence of boundary fluxes on ecological patchiness was motivated by the need to define the size of the domain necessary for the assessment of the impact of a sewage outflow on a coastal regime.  相似文献   

Origin of Fe-rich lherzolites and wehrlites from Tok,SE Siberia by reactive melt percolation in refractory mantle peridotites   总被引：2，自引：2，他引：0  

Dmitri?A.?IonovEmail author  Ingrid?Chanefo  Jean-Louis?Bodinier 《Contributions to Mineralogy and Petrology》2005,150(3):335-353

Lherzolite–wehrlite (LW) series xenoliths from the quaternary Tok volcanic field in the southeastern Siberian craton are distinguished from the more common lherzolite–harzburgite (LH) series by (a) low Mg numbers (0.84–0.89) at high modal olivine (66–84%) and (b) widespread replacement of orthopyroxene (0–12%) and spinel by clinopyroxene (7–22%). The LW series peridotites are typically enriched in Ca, Fe, Mn and Ti, and depleted in Si, Ni and Cr relative to refractory LH series rocks (Mg number ≥0.89), which are metasomatised partial melting residues. Numerical modelling of Fe–Mg solid/liquid exchange during melt percolation demonstrates that LW series rocks can form by reaction of host refractory peridotites with evolved (Mg numbers 0.6–0.7), silica-undersaturated silicate melts at high melt/rock ratios, which replace orthopyroxene with clinopyroxene and decrease Mg numbers. This process is most likely related to underplating and fractionation of basaltic magma in the shallow mantle, which also produced olivine–clinopyroxene cumulates found among the Tok xenoliths.  相似文献   

Peridotitic diamonds from Namibia: constraints on the composition and evolution of their mantle source     

Jeff W. Harris  Thomas Stachel  Ingrid Lost  Gerhard P. Brey 《Lithos》2004,77(1-4):209-223

About half the diamonds studied from the Cenozoic placer deposits along the Namibian coast belong to the peridotitic suite. The peridotitic mantle source is heterogeneous ranging from lherzolitic to strongly Ca depleted (down to 0.24 wt.% CaO in garnet) and shows large variations in Cr/Al ratio, illustrated by very low to very high Cr₂O₃ contents in garnet (2.6–17.3 wt.%). The Cr-rich end of this range includes exceptionally high Cr₂O₃ contents in Mg-chromite (70.7 wt.%) and clinopyroxene (3.6 wt.%). Garnet-olivine thermometry appears to indicate two groups, one that equilibrated at temperatures between 1200 and 1220°C and a second between 960 and 1100°C. Combined estimates of pressure and temperature based on garnet-orthopyroxene pairs indicate a large variance in geothermal gradients, corresponding to 38–42 mW/m² surface heat flow.

The trace-element composition of peridotitic garnet inclusions (determined by SIMS) also indicates large diversity. Two principal groups, corresponding to different styles of metasomatic source enrichment, are recognized. The first group ranges from extremely LREE_N-depleted patterns, through trough-shaped REE_N to sinusoidal patterns with the position of the first peak gradually moving from the LREE_N to the MREE_N. This series of REE patterns is interpreted to reflect a range of metasomatic agents with decreasing LREE/HREE. Only in the case of the two garnets with REE_N peaking at Sm–Eu is this process connected with enrichment in Zr, without significant introduction of Y and Ti. The metasomatism responsible is interpreted as reflecting percolation of CHO-fluids through harzburgite under sub-solidus conditions. A second group of garnets shows an increase from LREE_N–MREE_N and almost flat (lherzolitic garnet) to moderately declining MREE_N–HREE_N at super-chondritic levels. This second style of metasomatism is caused by an agent carrying HFSE and showing only moderate enrichment in LREE over HREE, which points towards silicate melts.  相似文献   

Effect of N content and soil texture on the decomposition of organic matter in forest soils as revealed by solid-state CPMAS NMR spectroscopy     

Marie-France Dignac  Heike Knicker  Ingrid Kgel-Knabner 《Organic Geochemistry》2002,33(12):157

N has a controlling effect on litter biodegradation in the forest floor, while stabilization of organic matter in the mineral soil may be influenced by physical parameters related to soil texture. In this study, in order to understand the processes involved in soil organic matter (SOM) formation, the chemical composition of SOM was followed and evaluated with regards to N contents and soil texture. Samples were taken on sites covered with Norway spruce and displaying contrasting values of C/N ratios in the forest floor. The chemical structure of OM was characterized using solid-state CPMAS ¹³C and ¹⁵N nuclear magnetic resonance (NMR) spectroscopy, along with Proton Spin Relaxation Editing (PSRE) sequences. Four groups of sampling sites were defined based on the NMR spectra of Oh and A horizons. In each group displaying similar NMR characteristics, N content and soil texture could be highly different among sites. Some Oh horizons with similar NMR spectra had very different N contents. Highly humified OM in Oh horizons were observed mainly on sites with low N contents. Some A horizons with different soil texture displayed similar OM chemical structure. High contents of O-alkyl C in some A horizons could originate from higher fresh root material input.  相似文献   

Regulations concerning risk analysis and their application in environmental safety protection in Norway     

Ingrid   rstad 《Marine pollution bulletin》1994,29(6-12):330-333

The Norwegian Petroleum Directorate (NPD), together with the State Pollution Control Authorities, administers the regulations concerning the implementation and use of risk analyses in petroleum activities.

This paper presents the main requirements contained in the Norwegian regulations concerning risk analyses, and focuses on their interaction with the legislation concerning safety for people, the environment, assets and financial interests.

In this context the NPD emphasizes the authorities' expectations with regard to the use of risk analyses in the management of risks to the environment, especially when conducting petroleum activities in environmentally vulnerable areas on the Norwegian continental shelf.  相似文献   

Die Eisvorbereitungszeiten für die Ostsee östlich der Linie Trelleborg—Arkona und für den Finnischen und Rigaischen Meerbusen sowie für die südlichen Randbezirke der Bottensee     

Ingrid Kühnel 《Ocean Dynamics》1967,20(1):1-6

Zusammenfassung Das langjährige Eisbeobachtungsmaterial der Ostseeanliegerstaaten gestattet die Bestimmung der Eisvorbereitungszeit in Abhängigkeit von der Lufttemperatur nach dem Verfahren von F. Nusser [1950] in leicht abgewandelter Form (Tabellen 1–7 und Abbildungen 1–4 u. 6). Die Eisbildung setzt an der gegliederten Nordküste des Finnischen Meerbusens und entlang des Stockholmer Schärengebietes schon nach einer Woche ein, während an der wenig gegliederten estnischen Küste und der schwedischen Südküste mindestens 10 Tage mehr zur Eisbildung erforderlich sind. Die Eisvorbereitungszeiten nehmen seewärts zu und erreichen auf offener See Werte von mehr als 40 Tagen; nach 30 Tagen ist der zentrale Teil des Finnischen Meerbusens mit Eis bedeckt. Im gleichen Zeitraum beschränkt sich die Eisbildung in der nördlichen und mittleren Ostsee auf einen schmalen Küstenstreifen.

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The Eisvorbereitungszeiten (number of consecutive days with negative mean air temperatures prior to the first occurrence of ice) in the Baltic Sea east of the Trelleborg—Arkona line, in the Gulfs of Finland and Riga, and in the southern areas of the Gulf of Bothnia

Summary The ice observational material collected over long years by the states bordering the Baltic Sea permits to determine the Eisvorbereitungszeit in dependence on the air temperature after the method of F. Nusser [1950] slightly modified (Tables 1–7 and Figs. 1–4, 6). The generation of ice at the rugged north coast of the Gulf of Finland and along the Stockholm skerries starts after one week already, while at the less rugged Estonian coast and at the south coast of Sweden at least 10 days more are required for the formation of ice. The Eisvorbereitungszeiten increase in the direction of the sea and attain values of more than 40 days in the open sea; after 30 days the central part of the Gulf of Finland is covered with ice. In the same period of time the formation of ice in the northern and central Baltic is restricted to a narrow coastal strip.

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Temps de formation des glaces dans la mer Baltique à l'Est de la ligne Trelleborg—Arkona, dans les golfes de Finlande et de Riga ainsi que dans les zones riveraines sud de la partie sud du golfe de Botnie

Résumé Les observations des glaces effectuées au cours de nombreuses années par les états riverains de la mer Baltique permettent de déterminer le temps de formation des glaces en fonction de la température de l'air suivant la méthode de F. Nusser [1950] légèrement modifiée (Tableaus 1 à 7 et Fig. 1 à 4 et 6). Le long de la côte nord du golfe de Finlande, encombrée d'îlots, et le long de la zone des Skärs de Stockholm, la glace se forme déjà au bout d'une semaine; tandis que le long de la côte d'Estonie, peu encombrée, et de la côte sud de Suède, il faut au moins 10 jours de plus pour qu'il y ait formation de glace. Les temps de formation augmentent vers le large et dépassent 40 jours en pleine mer; la partie centrale du golfe de Finlande est couverte de glace au bout de 30 jours. Pour un même temps, la formation de glace dans la Baltique nord et centrale se limite à un étroit ruban côtier.

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Die Eisabschmelzzeiten für die Ostsee östlich der Linie Trelleborg-Arkona und für den Finnischen und Rigaischen Meerbusen sowie für die südlichen Randbezirke der Bottensee     

Dipl.-Met. Ingrid Kühnel 《Ocean Dynamics》1968,21(1):15-20

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