name_de: Röntgenfluoreszenz Spektrometer
name_en: Röntgenfluoreszenz Spektrometer
model: XEPOS
url:
manufacturer: Spectro
year: 0
location_de: Erlangen
location_en: Erlangen
usage_de: Auch für externe Nutzer
usage_en: For external users too
description_de:
Messung der Konzentration von Hauptelementen und ausgewählten Spurenelementen in Gesteinen und anderen Festkörpern
description_en:
feature_de:
feature_en:
pictures: <QuerySet []>
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funding_sources: <QuerySet []>
projects: <QuerySet [<Project: The origin of volcanic flux variations along Pacific hotspot tracks: Plume-lithosphere interaction vs. plume pulsations (SOPITA), SOPITA, , , <p>The volcanic flux at the Hawaiian hotspot generally increased over the last 30-80 Ma, with second-order variations over 10~15 Ma. This significant increase remains unexplained by classic plume theory, which predicts that a plume-head stage with massive volcanic activity is followed by a plume-tail stage with ever decreasing activity. In particular, 25-30 Ma ago there was a sharp increase in the Hawaiian volcanic flux by a factor ~4 that appears to be associated with an increase in Pacific plate motion from ~60 km/Ma to ~100 km/Ma.At about the same time there was a surge across the South Pacific of young low-volume hotspot tracks. It is unclear from our understanding of the poorly sampled Hawaiian track if these volcanic flux variations are related to speed up of the Pacific plate or to pulsations of the Hawaiian plume. In order to explain the coupled observations of faster plate speed and increased volcanic flux we aim to explore three young, relatively low-volume Pacific hotspot tracks. High–precision geochronological data for multiple hotspot tracks is the only way of extracting fundamental new information from the intraplate record about the poorly-sampled young end of the Hawaiian hotspot track. We propose to determine high-precision ages using the next generation of multi-collector mass spectrometer for 111 samples from the Foundation, Easter and Pukapuka-Rano Rahi volcanic tracks. We will use these new data to (1) pinpoint the timing of Pacific plate-speed increases and variations in hotspot volcanic flux, and (2) understand the underlying mechanisms controlling volcanic flux variations at Pacific hotspots.<br /></p>, , 2019-06-01, 2021-05-31, , 2021-05-31, Third party funded individual grant, True>, <Project: Magma formation and evolution in an oceanic island arc - back-arc system: a case study from the Tonga arc and Valu Fa Ridge, , , , , , 2018-02-01, 2021-01-31, , 2021-01-31, Third party funded individual grant, True>, <Project: Bildung, Transport und Entwicklung von Magmen in einem ozeanischen, ultralangsam spreizenden Rift, , , , , , 2017-07-01, 2020-06-30, , 2020-06-30, Third party funded individual grant, True>, <Project: Behaviour of Igneous Systems and Metal endowment across Arcs (BISMArc), BISMArc, , , <p>
<span style="font-family: ArialMT; font-size: 11pt;">Rifting of arc crust may host large hydrothermal systems with the potential of forming large mineral deposits of economic relevance. The highly variable structural and magmatic conditions across arcs into the backarc environment provide a unique opportunity to investigate a large diversity of magmatic and hydrothermal systems (e.g., Hannington et al., 2005). Here, we aim at quantifying both the changes in the melting regime (physical conditions, melting and mantle sources) in the transition from arc front into backarc and the impact on metal potential. A direct contribution of magmatic volatiles to (ore-forming) hydrothermal fluids is known from island arc volcanoes but the general links between oxidation state, sulphur saturation and magmatic degassing on metal behaviour in silicate melts are still a matter of active debate. Jenner et al. (2010, 2015) pointed at the importance of the onset of magnetite crystallization for sulphur saturation and thus chalcophile element behaviour. However, their magnetite crisis may be restricted to specific physicochemical circumstances (such as closed system behaviour, oxidation state and melt composition etc.) and needs to be investigated in different magmatic systems (e.g., arc to backarc transition) and spatial resolution. Here, we are aiming at disentangling the influence of mantle sources and melting on the metal enrichment in melts and volatiles and the geological framework of pathways for melts and volatiles at a scale that is relevant to resource exploration. This project consists of two sub-projects, one with an emphasis on mantle sources, melting conditions and magmatic differentiation providing the basic framework and the other focused on seafloor geology (ascent paths and geodynamics) and the distinct behaviour of metals (especially Cu, Au and the so-called critical metals) and volatiles (H2O, CO2, Cl, S) in the melts. However, these two projects are closely linked (especially through the aspect of magma evolution), requiring close collaboration and frequent exchange. The focus of this study will be on the Tonga-Kermadec subduction system, where extensive sample material is readily available and two additional research cruises have been recently approved (ARCHIMEDES I and TongaRIFT). </span></p>, <p>
<span style="font-family: ArialMT; font-size: 14.666666984558105px;">Rifting of arc crust may host large hydrothermal systems with the potential of forming large mineral deposits of economic relevance. The highly variable structural and magmatic conditions across arcs into the backarc environment provide a unique opportunity to investigate a large diversity of magmatic and hydrothermal systems (e.g., Hannington et al., 2005). Here, we aim at quantifying both the changes in the melting regime (physical conditions, melting and mantle sources) in the transition from arc front into backarc and the impact on metal potential. A direct contribution of magmatic volatiles to (ore-forming) hydrothermal fluids is known from island arc volcanoes but the general links between oxidation state, sulphur saturation and magmatic degassing on metal behaviour in silicate melts are still a matter of active debate. Jenner et al. (2010, 2015) pointed at the importance of the onset of magnetite crystallization for sulphur saturation and thus chalcophile element behaviour. However, their magnetite crisis may be restricted to specific physicochemical circumstances (such as closed system behaviour, oxidation state and melt composition etc.) and needs to be investigated in different magmatic systems (e.g., arc to backarc transition) and spatial resolution. Here, we are aiming at disentangling the influence of mantle sources and melting on the metal enrichment in melts and volatiles and the geological framework of pathways for melts and volatiles at a scale that is relevant to resource exploration. This project consists of two sub-projects, one with an emphasis on mantle sources, melting conditions and magmatic differentiation providing the basic framework and the other focused on seafloor geology (ascent paths and geodynamics) and the distinct behaviour of metals (especially Cu, Au and the so-called critical metals) and volatiles (H2O, CO2, Cl, S) in the melts. However, these two projects are closely linked (especially through the aspect of magma evolution), requiring close collaboration and frequent exchange. The focus of this study will be on the Tonga-Kermadec subduction system, where extensive sample material is readily available and two additional research cruises have been recently approved (ARCHIMEDES I and TongaRIFT). </span></p>, 2017-01-01, 2019-12-31, , 2019-12-31, Third party funded individual grant, True>, <Project: Tectonic origin of the Troodos Ophiolite from three-dimensional geochemical mapping of the lava pile, , , , <p>
Ophiolites are often used to infer the internal structure of the oceanic crust and the processes by which it is formed, but most ophiolites were not formed in typical mid-ocean ridge settings. Instead, they appear to have formed close to former subduction zones, but the exact tectonic setting in which they were formed is debated. If ophiolites represent fore-arc crust formed during subduction initiation events, then they provide insights into the initiation of subduction zones, an outstanding unresolved question in plate tectonics. If ophiolites were formed in back-arc or plate edge settings they may represent useful analogues for the internal structure of oceanic crust. If they were formed at a ridge-trench-trench or ridge-trench-transform triple junction then they could be used to infer mantle wedge structure and processes. These tectonic models predict different geochemical variations in ophiolite lavas with space and time. We will map out the 3D gechemical structure of the Troodos Ophiolite of Cyprus, one of the best preserved an exposed ophiolites. We will use major and trace element microanaysis of fresh volcanic glass in order to avoid the effects of alteration. Detailed high resolution sampling of sections through the Troodos volcanic section on both the northern and southern margins of the ophiolite will be used to determine the chemical evolution of magmatism and test hypotheses for the tectonic origin of this ophiolite.</p>, , 2016-11-01, 2019-10-31, , 2019-10-31, Third party funded individual grant, True>, <Project: Temperature-related stresses as a unifying principle in ancient extinctions (TERSANE), TERSANE, https://www.gzn.fau.de/palaeoumwelt/projects/tersane/index.html, FOR 2332: Temperature-related stresses as a unifying principle in ancient extinctions (TERSANE), <p>
Combined with local and regional anthropogenic factors, current human-induced climate warming is thought to be a major threat to biodiversity. The ecological imprint of climate change is already visible on land and in the oceans. The imprint is largely manifested in demographic/abundance changes and phenological and distribution shifts, whereas only local extinctions are yet attributable to climate change with some confidence. This is expected to change in the near future owing to direct heat stress, shortage of food, mismatches in the timing of seasonal activities, geographic barriers to migration, and new biological interactions. Additional stressors are associated with climate warming in marine systems, namely acidification and deoxygenation. Ocean acidification is caused by the ocean's absorption of CO2 and deoxygenation is a result of warmer water, increased ocean stratification and upwelling of hypoxic waters. The combination of warming, acidification and deoxygenation is known as the "deadly trio". Temperature is the most pervasive environmental factor shaping the functional characteristics and limits to life and is also central to the generation and biological effects of hypoxic waters and to modulating the effects of ocean acidification, with and without concomitant hypoxia. Due to the key role of temperature in the interaction of the three drivers we termed these temperature-related stressors (TRS).</p>, , 2016-07-01, 2019-06-30, , 2019-06-30, Third Party Funds Group - Sub project, True>, <Project: The Rio Grande Rise and Jean Charcot Seamount Chain - microcontinents or the trail of the Tristan-Gough hotspot? (RIOGRANDE - MSM82), RIOGRANDE - MSM82, , , <p>The Rio Grande Rise (RGR) is a massive plateau and seamount province in the SW Atlantic that has been assumed to represent a large igneous province formed by voluminous magmatic activity of the Tristan-Gough mantle plume on the South American plate. But new evidence showing that the RGR might be a sliver of continental crust that was captured, and possibly rifted, at the time of continental breakup, is throwing considerable doubt on a hotspot origin. We propose a combined seismic, geochemical, geo- and thermochronological study of the nature of the deep and shallow RGR basement to test our hypothesis that the RGR is a microcontinent that has been modified by a complex tectonic and magmatic history, including 1000 km long rifts, associated with buoyant plume upwelling and formation of the Jean Charcot Seamount Chain. These data will determine the relative amounts of continental and oceanic crust, age and origin of the volcanic rocks, and chemical changes with time. The results will have important implications for the understanding of continental rifting and opening of ocean basins and the role of microcontinents in the formation of hotspot trails.<br /></p>, , 2019-03-01, 2019-04-30, , 2019-04-30, Third party funded individual grant, True>, <Project: Formation and evolution of magmas due to subduction of sediments: a case study of the submarine Paphsanias Volcano, Aegean Arc (PAPHSANIAS), PAPHSANIAS, , , <p>
Andesite magmas at active continental margins may form due to assimilation-fractional crystallization processes from basaltic mantle melts or due to direct partial melting of unusual mantle rocks resulting, for example, from mixing of sediment melts with peridotite. Magmas of the Aegean Arc indicate a reaction of the melts with the crust during the ascent as well as a strong input of sediment into the melting zone of the mantle wedge. These different mixing processes are difficult to define in most rocks and require detailed studies of melt (glass) and mineral compositions. Thus, submarine lavas are best suited for a study of andesite formation because melts are quenched and their composition including volatile contents can be determined. The volcanoes of the western Aegean mainly erupted effusive lavas in domes and flows rather than showing explosive activity. We propose a cruise to the westernmost submarine volcano Paphsanias of the Aegean Arc that has not been studied petrologically and geochemically. We suggest studying and sampling this volcano using an ROV that will give us stratigraphic control of the samples. The ROV dives will allow determining the relative abundance of lavas and volcaniclastic rocks and yield insights into the apparently different magma ascent and eruption processes in the western volcanoes. Given the young age of the Paphsanias volcano the crater may also show hydrothermal activity that we will be able to observe and sample using the ROV.Andesite magmas at active continental margins may form due to assimilation-fractional crystallization processes from basaltic mantle melts or due to direct partial melting of unusual mantle rocks resulting, for example, from mixing of sediment melts with peridotite. Magmas of the Aegean Arc indicate a reaction of the melts with the crust during the ascent as well as a strong input of sediment into the melting zone of the mantle wedge. These different mixing processes are difficult to define in most rocks and require detailed studies of melt (glass) and mineral compositions. Thus, submarine lavas are best suited for a study of andesite formation because melts are quenched and their composition including volatile contents can be determined. The volcanoes of the western Aegean mainly erupted effusive lavas in domes and flows rather than showing explosive activity. We propose a cruise to the westernmost submarine volcano Paphsanias of the Aegean Arc that has not been studied petrologically and geochemically. We suggest studying and sampling this volcano using an ROV that will give us stratigraphic control of the samples. The ROV dives will allow determining the relative abundance of lavas and volcaniclastic rocks and yield insights into the apparently different magma ascent and eruption processes in the western volcanoes. Given the young age of the Paphsanias volcano the crater may also show hydrothermal activity that we will be able to observe and sample using the ROV.</p>, , 2017-04-15, 2018-03-31, , 2018-03-31, Third party funded individual grant, True>, <Project: The role of mixing processes in andesite genesis - deep sediment recycling versus shallow crustal contamination, , , , <div>
Andesites are the typical volcanic rocks at active continental margins and the average continental crust has an andesitic composition. Many andesitic magmas form by complex mixing processes involving sedimentary material that is either subducted into the mantle wedge or may be assimilated in the crust by the ascending magma. The Aegean arc represents the subduction zone with one of the highest sediment recycling rates on Earth and the magmas show whole-rock geochemical evidence of a significant sediment contribution. In order to define the depths of the magma sources and the mixing processes we suggest to study the major and trace element as well as Sr-Nd-Hf-Pb-O isotope composition of minerals like olivine, amphibole, clinopyroxene, and plagioclase and potential glass inclusions in lavas from the Methana/Aegina volcanoes in the Aegean arc. The mineral phases allow insights into the mixing processes of different end-members at different depths that can be determined by thermo-barometry. The Methana/Aegina lavas are well-suited for such a case study because they are geochemically well-described and variable with extreme compositions of the mixing end-members and they contain abundant mineral phases.</div>, , 2015-01-01, , , 2018-01-01, Third party funded individual grant, True>, <Project: Durchführung von Spurenelementmessungen und Nd-Pb Isotopenmessungen an Manganknollen und assoziierten Sedimenten, , , , , , 2017-05-01, 2017-12-31, , 2017-12-31, Third party funded individual grant, True>, <Project: Hotspot Rücken Südatlantik, , , , , , 2012-12-01, 2015-11-30, , 2015-11-30, Third party funded individual grant, True>, <Project: Volcanism and hydrothermal venting in the Coriolis Basins, New Hebrides Island Arc (COVOLVE), COVOLVE, , , <p>
Junges Rifting (< 3 Ma) im südlichen Neue Hebriden Inselbogen erzeugte drei vulkanische und hydrothermal aktive Becken im Coriolis Becken, in denen z.T. alkaline Magmen mit Anreicherungen an Nb und Ta auftreten. Weiterhin zeigt der Vanuatu Inselbogen eine starke Dynamik mit einem Umspringen der vulkanischen Aktivität weiter nach Osten. Durch das Rifting wurden tiefe Bereiche des Inselbogens freigelegt, die offenbar bis 7 Ma alt sind. Eine detaillierte stratigraphische Beprobung dieser Riftflanken und der jungen Vulkane im südlichen Inselbogen und im Backarc ermöglichen daher einmalige Möglichkeiten zur Entwicklung der Magmen, ihres Aufstiegs und ihrer Quellen in den letzten 7 Ma. Drei Vorkommen von hydrothermalen Quellen bzw. Präzipitaten wurden in den Coriolis Troughs bisher beschrieben aber nicht detailliert untersucht. Mit einem ROV sollen die zeitliche und chemische Variabilität zwischen Magmengenese, Vulkanismus und Hydrothermalismus im Gebiet der Coriolis Becken untersucht werden. Von Bedeutung sind Fragen der lithologischen Kontrolle durch volatilreiche, alkaline Magmen und Einflüsse vulkanischer Entwicklung auf metallogenetische Prozesse sowie der Fluiddynamik und –entwicklung. Die Auswirkung unterschiedlicher Wassertiefen auf die Entgasungsprozesse und Zusammensetzung hydrothermaler Fluide steht dabei im Vordergrund. Ein weiterer Schwerpunkt liegt in der Untersuchung der kleinräumigen Variabilität magmatischer Differenziation im Inselbogen und deren Rückkopplung auf Metallfraktionierung und hydrothermale Aktivität. Von biologischer Seite steht das Verständnis der Kontrolle der Habitate sowie der Faunenverteilung und -zusammensetzung an hydrothermalen Austritten im Vordergrund. </p>, , 2013-06-01, 2015-05-31, , 2015-05-31, Third party funded individual grant, True>, <Project: Magmatische und sedimentologische Entwicklung eines ozeanischen Plateaus am Beispiel der Azoren, , , , <p>
Die Azoren liegen auf einem ozeanischen Plateau mit etwa 10-12 km mächtiger Kruste basaltischer Zusammensetzung. Das Plateau mit der verdickten Kruste entwickelte sich offenbar durch verstärkten Vulkanismus vor etwa 6-4 Ma. Seit 4 Ma entsteht am Mittelatlantischen Rücken dünnere Kruste, da die Schmelzanomalie abgeschwächt ist und so das Azoren Plateau geteilt wird. Der magmatische Puls vor 6-4 Ma wurde möglicherweise durch einen Mantelplume-Kopf ausgelöst, der zur Bildung des Plateaus aus ozeanischen (Flut)basalten führte. Die Insel Santa Maria am östlichen Rande des Plateaus reflektiert eine Schlüsselrolle in der Bildung des Plateaus. Das Projekt hat drei Ziele: (1) die zeitliche und chemische Entwicklung des Vulkanismus auf dem Plateau zu klären (z.B. der Übergang von tholeiitischen Flutbasalten zu alkalinen Magmen der Inseln), (2) die Wechselwirkung zwischen der Azoren Schmelzanomalie und dem Mittelatlantischen Rücken zu bestimmen, (3) den Magmentransport und die Eruptionsmechanismen in der frühen Plateaubildungsphase zu bestimmen und (4) den zeitlichen Rahmen und biogeographischen Kontext sowie Diagenesepfade der eingeschalteten Karbonate zu bestimmen.</p>, , 2009-09-01, 2011-09-30, , 2011-09-30, Third party funded individual grant, True>]>
publications: <QuerySet [<Publication: Variation of melting processes and magma sources of the early Deccan flood basalts, Malwa Plateau, India>, <Publication: Geochemical mapping of a paleo-subduction zone beneath the Troodos
Ophiolite>, <Publication: Correlated Changes Between Volcanic Structures and Magma Composition in the Faial Volcanic System, Azores>, <Publication: Evidence for melting of subducting carbonate-rich sediments in the western Aegean Arc>, <Publication: Mantle sources and magma evolution of the Rooiberg lavas, Bushveld Large Igneous Province, South Africa>, <Publication: Magmatic evolution and source variations at the Nifonea Ridge (New Hebrides Island Arc)>, <Publication: Primitive andesites from the Taupo Volcanic Zone formed by magma mixing>, <Publication: Controls on melting at spreading ridges from correlated abyssal peridotite - mid-ocean ridge basalt compositions>, <Publication: Constraints on the magmatic evolution of the oceanic crust from plagiogranite intrusions in the Oman ophiolite>, <Publication: Spatial variability of source composition and petrogenesis in rift and rift flank alkaline lavas from the Eger Rift, Central Europe>, <Publication: Formation of andesite melts and Ca-rich plagioclase in the submarine Monowai volcanic system, Kermadec arc>, <Publication: Melts of sediments in the mantle wedge of the Oman ophiolite>, <Publication: The magmatic evolution of young island arc crust observed in gabbroic to tonalitic xenoliths from Raoul Island, Kermadec Island Arc>, <Publication: Formation of the Troodos Ophiolite at a triple junction: Evidence from trace elements in volcanic glass>, <Publication: Constraints on the formation of geochemically variable plagiogranite intrusions in the Troodos Ophiolite, Cyprus>, <Publication: Petrology and geochemistry of the Tertiary Suez rift volcanism, Sinai, Egypt>]>
fobes: <QuerySet []>
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