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  • 1
    Publication Date: 2023-12-19
    Description: 〈title xmlns:mml="http://www.w3.org/1998/Math/MathML"〉Abstract〈/title〉〈p xmlns:mml="http://www.w3.org/1998/Math/MathML" xml:lang="en"〉The MErcury Radiometer and Thermal Infrared Spectrometer instrument onboard the BepiColombo spacecraft is designed to investigate Mercury’s surface in the mid‐infrared (mid‐IR). Based on MESSENGER data and modeling, Mercury is thought to be evolved under highly reducing conditions (e.g., McCubbin et al., 2017, 〈ext-link ext-link-type="uri" xlink:href="https://doi.org/10.1002/2017JE005367"〉https://doi.org/10.1002/2017JE005367〈/ext-link〉; Namur & Charlier, 2017, 〈ext-link ext-link-type="uri" xlink:href="https://doi.org/10.1038/ngeo2860"〉https://doi.org/10.1038/ngeo2860〈/ext-link〉). The modeling also indicates that Mercury's surface is rich in feldspar. However, it is unknown if reducing conditions during the emplacement of volcanic melts have an influence on the IR properties of feldspars. Therefore, we investigated basaltic samples from the Bühl quarry in northern Hesse, Germany, that evolved under reducing conditions in the mid‐IR and compared the spectra with samples that experienced more oxidizing conditions during their formation. The Bühl samples are feldspar‐rich and contain metallic iron in some areas. Our investigations show that there are no differences between feldspars that formed under different oxidizing conditions. All spectral properties could be explained by well‐known factors that affect mid‐IR spectra of silicates.〈/p〉
    Description: Plain Language Summary: ESA's and Japan Aerospace Exploration Agency’s spacecraft BepiColombo is equipped, beside other instruments, with a thermal infrared (IR) radiometer and spectrometer called MErcury Radiometer and Thermal Infrared Spectrometer (MERTIS). For the accurate interpretation of the data from the MERTIS instrument, laboratory analog material is necessary. This analog material must fulfill different characteristics, such as different chemical and mineralogical compositions. Another not yet studied property is the availability of oxygen during the formation of the minerals. Depending on how much oxygen is available, different minerals form. However, this is an important feature, because Mercury is thought to have evolved under highly reducing conditions, as opposed to Earth where nearly all material formed significant more oxidizing conditions. One phase that is strongly associated with reducing magma formation conditions is metallic iron. There are only few natural outcrops on Earth, were stronger reducing conditions were present so that metallic iron could be formed. One of these outcrops is the Bühl quarry in northern Hesse, Germany. From there we used different samples to analyze the effect of oxygen availability on mid‐IR spectra of plagioclase feldspars.〈/p〉
    Description: Key Points: 〈list list-type="bullet"〉 〈list-item〉 〈p xml:lang="en"〉We present infrared spectra of basaltic samples from the Bühl, Hesse, Germany in preparation of the MERTIS experiment〈/p〉〈/list-item〉 〈list-item〉 〈p xml:lang="en"〉Comparison of feldspars formed at different oxygen fugacities showed no spectral differences〈/p〉〈/list-item〉 〈list-item〉 〈p xml:lang="en"〉This is an important result for MERTIS, which will investigate Mercury that formed under reducing conditions〈/p〉〈/list-item〉 〈/list〉 〈/p〉
    Description: DLR
    Description: http://bc-mertis-pi.uni-muenster.de/
    Keywords: ddc:549 ; infrared reflectance spectroscopy ; feldspars ; Bühl basalt ; reducing conditions ; Mercury ; MERTIS
    Language: English
    Type: doc-type:article
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  • 2
    Publication Date: 2023-06-23
    Description: Feldspars are major components of terrestrial planetary surfaces. For future space application and the setup of a comprehensive reference database, Na- and K-rich alkali feldspars, NaAlSi3O8 – KAlSi3O8, have been investigated by infrared reflectance spectroscopy. We related the feldspar spectra to the chemical composition and state of Al,Si order/disorder. The infrared measurements were analyzed with respect to band shifts and peak shapes using the autocorrelation function. Natural samples served as starting materials. Some samples were treated by the alkali exchange method to produce pure end-members, which were then heated to generate various states of Al,Si disorder. X-ray diffraction (XRD) methods served to determine the Al,Si distribution. Our autocorrelation allowed to differentiate between the compositional and the order/disorder influences seen in the spectra in the wavelength range between 7 μm up to 14 μm (1429 cm− 1 to 714 cm− 1). Space missions often analyze the surfaces of planetary bodies using remote sensing. Therefore, our results are essential to characterize and distinguish alkali feldspars on the surfaces of terrestrial planetary bodies like Mercury.
    Description: Deutsches Zentrum für Luft- und Raumfahrt https://doi.org/10.13039/501100002946
    Keywords: ddc:549 ; Alkali feldspars ; Infrared spectroscopy ; X-ray diffraction ; Al,Si distribution
    Language: English
    Type: doc-type:article
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  • 3
    Publication Date: 2023-01-13
    Description: Massif‐type anorthosite and comagmatic associations of rutile‐bearing ilmenitite (RBI) and oxide‐apatite‐rich amphibolite (OARA) from the Chiapas Massif Complex (CMC) in southeastern Mexico display a protracted billion‐year accessory mineral record encompassing magmatic crystallization at c. 1.0 Ga to recent ductile shear deformation at c. 3.0 Ma. Multiple discrete zircon populations between these age end‐members resulted from neoformation/recrystallization during local to regional metamorphism that affected the southeastern portion of the CMC. The ubiquitous presence of relict baddeleyite (ZrO2), along with various zircon generations spatially associated with pristine to partly retrogressed Zr‐bearing igneous and metamorphic minerals (e.g., ilmenite, rutile, högbomite and garnet), suggests significant Zr diffusive re‐equilibration (exsolution) during slow cooling and mineral breakdown followed by crystallization of baddeleyite. The subsequent transformation of baddeleyite into zircon was likely driven by reaction with Si‐bearing fluids in several geochronologically identified metamorphic stages. Strikingly contrasting compositional signatures in coeval zircon from anorthosite (silicate‐dominated) and comagmatic RBI (Ti‐Fe‐oxide‐dominated) indicate a major role of fluids locally equilibrating with the rock matrix, as indicated by distinct zircon trace element and oxygen isotopic compositions. A high‐grade metamorphic event at c. 950 Ma is likely responsible for the formation of coarse‐grained rutile (~0.1–10 mm in diameter), srilankite, zircon and garnet with rutile inclusions as well as metamorphic högbomite surrounding Fe‐Mg spinel. Zr‐in‐rutile minimum temperatures suggest 〉730°C for this event, which may correlate to rutile‐forming granulite facies metamorphism in other Grenvillian‐aged basement rocks in Mexico and northern South America. A younger generation of baddeleyite exsolution occurred during post‐peak cooling of coarse‐grained rutile, reflected in rimward Zr depletion and formation of discontinuous baddeleyite coronas. Baddeleyite around rutile was then transformed into zircon possibly during subsequent metamorphism at c. 920 or 620 Ma, resulting from syn‐kinematic and contact metamorphism, respectively. Regional metamorphism at c. 450 and 250 Ma extensively overprinted the existing zircon population, especially during the Triassic event, as suggested by a significant presence of zircon with this age. Nearly pristine baddeleyite occurring interstitial to ilmenite yielded an isochron age of c. 232 Ma according to in situ U–Pb secondary ion mass spectrometry (SIMS), suggesting either formation during metamorphic peak conditions or post‐peak cooling. Zircon with ages of c. 80–100 Ma in anorthosite is identified for the first time within the CMC and coincides with cooling ages of c. 100 Ma for coarse‐grained rutile. This age is similar to those of rocks occurring ~200 km further to the east in Guatemala, which are also bounded to the Polochic fault system but overprinted by eclogite facies metamorphism. A high‐pressure event in the southern CMC after 200 Ma, however, is presently unsupported. Although the abundance of rutile and ilmenite is unusually high in the CMC anorthosite assemblage compared with common igneous rocks, the reactions documented here nonetheless stress the importance of these phases for generating Zr‐bearing accessory minerals over a wide range of metamorphic conditions.
    Description: Consejo Nacional de Ciencia y Tecnología (CONACYT) http://dx.doi.org/10.13039/501100003141
    Description: Deutsche Forschungsgemeinschaft (DFG)
    Keywords: ddc:549 ; Diffusion ; SIMS ; Srilankite ; Ti‐Fe deposits ; Ti‐in‐zircon ; Zr‐in‐rutile
    Language: English
    Type: doc-type:article
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  • 4
    Publication Date: 2023-12-22
    Description: "TRANSCITY" ist ein partizipatives, sozialökologisches Forschungsprojekt, das hinsichtlich seiner transformativen Wirkung im folgenden Text exemplarisch anhand der Arbeiten mit und in der Stadt Essen vorgestellt und analysiert wird. Im ersten Abschnitt werden die vielseitigen Herausforderungen der Klimakrise herausgearbeitet, die den Bezugsrahmen des Projektes bilden. Im Mittelpunkt der Projektvorstellung stehen die Projektidee, die Zielsetzungen sowie das Projektdesign und die Forschungsmethoden. Im abschließenden Kapitel werden die transformativen Wirkungen untersucht. Am Ende folgt ein zusammenfassender Ausblick.
    Keywords: ddc:300
    Repository Name: Wuppertal Institut für Klima, Umwelt, Energie
    Language: German
    Type: bookpart , doc-type:bookPart
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  • 5
    Publication Date: 2023-12-22
    Description: Um die Treibhausgasneutralität bis 2045 zu erreichen, wird unter anderem erforderlich sein, dass die Industrie klimaneutrale Produktionsweisen entwickelt und umsetzt. Damit einher gehen gesellschaftliche Aushandlungsprozesse darüber, welche neuen Technologien eingesetzt werden und welche Auswirkungen vor Ort akzeptiert werden. Das Ausmaß an Akzeptanz gegenüber Technologien oder Infrastrukturen beeinflusst neben anderen Faktoren die spezifische Ausgestaltung der Transformation. Mangelnde Akzeptanz kann die Entwicklung von Transformationspfaden verlangsamen oder gar verhindern, und zu Protesten, beispielsweise von lokalen Initiativen oder von etablierten Klimaschutz- und Umweltverbänden, führen. Dieses Wuppertal Paper stellt die Frage in den Fokus, welchen Einfluss Protestbewegungen auf öffentliche Akzeptanz haben bzw. haben könnten. Grundlage dafür sind empirische Ergebnisse aus dem Projekt Protanz.NRW zu Protesten und Akzeptanz im Kontext der Industrietransformation in NRW. Darauf aufbauend wird ein Protest-Akzeptanz-Modell entwickelt und es werden Hypothesen abgeleitet, wie unterschiedliche Protestgruppen die öffentliche Akzeptanz von Technologien für die Industrietransformation in NRW beeinflussen können. Abschließend werden Handlungsempfehlungen für Politik und Industrie abgeleitet sowie Forschungsbedarfe aufgezeigt.
    Keywords: ddc:300
    Repository Name: Wuppertal Institut für Klima, Umwelt, Energie
    Language: German
    Type: workingpaper , doc-type:workingPaper
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  • 6
    Publication Date: 2024-01-25
    Description: Für die Landesregierung Nordrhein-Westfalen (NRW) ist die industriell genutzte Kohlenstoffabscheidung und -speicherung (engl. industrial carbon capture and storage, kurz iCCS) ein zentraler Baustein für den Übergang zu einer klimaneutralen Industrie bis 2045. Dafür braucht es aber eine breite gesellschaftliche Akzeptanz - zumal Pläne zur CO2-Abscheidung bei Kohlekraftwerken vor über zehn Jahren schon einmal an mangelnder gesellschaftlicher Akzeptanz gescheitert sind. In diesem In Brief haben die Autor*innen die Ergebnisse von zwei durchgeführten Akzeptanzstudien zu iCCS in NRW zusammengefasst und diskutieren, welche Handlungsempfehlungen sich daraus ergeben.
    Keywords: ddc:300
    Repository Name: Wuppertal Institut für Klima, Umwelt, Energie
    Language: German
    Type: workingpaper , doc-type:workingPaper
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  • 7
    Publication Date: 2024-01-25
    Description: Nordrhein-Westfalen (NRW) ist Heimat energieintensiver Industrien wie der Stahl- und Chemieindustrie. Künftig wird grüner Wasserstoff notwendig sein, damit die Industrie in NRW Klimaneutralität erreichen kann. Die Herausforderungen hierbei sind jedoch vielfältig - auch wenn die Akzeptanz für grünen Wasserstoff sowohl in der Gesellschaft als auch bei unmittelbar beteiligten Akteursgruppen hoch ist. Die Autor*innen fassen in diesem In Brief die Ergebnisse von zwei durchgeführten Akzeptanzstudien zu grünem Wasserstoff in NRW zusammen und diskutieren, welche Handlungsempfehlungen sich daraus ergeben.
    Keywords: ddc:300
    Repository Name: Wuppertal Institut für Klima, Umwelt, Energie
    Language: German
    Type: workingpaper , doc-type:workingPaper
    Format: application/pdf
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