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Werterhaltungsstrategien für elektrische Traktionsmotoren, Teilvorhaben: Demontage und Prozessautomatisierung

Werterhaltungsstrategien für elektrische Traktionsmotoren, Teilvorhaben: Befundung, Aufarbeitung und nachhaltige Designkonzepte

Dissolved and particulate trace metal and rare earth element (REE) concentrations during a mesocosm based phytoplankton bloom simulating intertidal coastal conditions

We analyzed concentrations of dissolved and particulate trace metals, including iron (Fe), manganese (Mn), vanadium (V), molybdenum (Mo), thallium (Tl), and rare earth elements (REE), during a mesocosm-based phytoplankton summer bloom mimicking the intertidal zone of the southern North Sea (Jade Bay). The studies aimed to identify key drivers controlling their biogeochemical cycling in dynamic, high-productivity coastal environments. Our results highlight the tidally influenced coastal zone as a critical interface that alters the behavior of supposedly conservative elements such as Mo and Tl (Mori et al., 2021) as well as natural and anthropogenic REE (incl., lanthanum, samarium, and gadolinium) (Mori et al., under review). Trace metal concentrations and shale-normalized REE patterns, determined by quadrupole inductively coupled plasma–mass spectrometry (ICP-MS) and inductively coupled plasma–optical emission spectrometry (ICP-OES), were combined with biogeochemical bulk parameters and pigment-based assessments of phytoplankton growth and community composition (Mustaffa et al., 2020). Trace metal and REE cycling were evaluated in relation to phytoplankton dynamics, particulate organic matter composition (C, N, P), dissolved organic carbon, total dissolved nitrogen, and macronutrient concentrations (nitrate, ammonium, silicate, and inorganic phosphate). The dataset was obtained during a Planktotron-based mesocosm experiment conducted within the framework of the Coastal Ocean Darkening project (Mustaffa et al., 2020).

Trace element concentration of minerals in the Morro São João malignites (Serra do Mar, Brazil)

The Morro São João intrusion is located in the easternmost part of the Serra do Mar province, along the Cabo Frio lineament (Fig. 1) and has an area of approximately 10 km². It is a Late Cretaceous intrusion formed by clinopyroxenites, melagabbros, shonkinites, malignites, nepheline syenites, and phonolite dikes, without olivine, and is thought to have formed by closed system crystallization of a fairly evolved tephritic melt of potassic/ultrapotassic affinity (cf. Brotzu et al., 2007). We have analyzed two malignites, and specifically, their liquidus phases (clinopyroxene, titanite, garnet, amphibole). Analyzing the trace elements in these minerals helps us to better understand the different fractionation of the elements in these coexisting phases, and the implications for the evolution processes that occurred in the Morro São João magma reservoir. These analyses also provided important information about the concentration of rare earth elements (REEs) and high field strength elements (HFSEs), and their change with the magmatic evolution of the suite. This publication results from work conducted under the transnational access/national open access action at Mass spectrometry la-icp laboratory (IGG-CNR, Italy) supported by WP3 ILGE - MEET project, PNRR - EU Next Generation Europe program, MUR grant number D53C22001400005.

Trace element analysis of the main minerals in the Salitre lamprophyre (APIP, Brazil)

The Upper Cretaceous Salitre intrusion, subdivided into Salitre I and Salitre II and dated to ~86-82 Ma by Sonoki and Garda (1988), is part of the Alto Paranaíba Igneous Province (APIP, Fig. 1) in Brazil, which is one of the largest ultrapotassic / carbonatitic / kimberlitic provinces in the world. The intrusion is characterized by the presence of lamproites, carbonatites and one lamprophyre (analyzed here), as well as along with a variety of intrusive cumulitic rocks. Among the Salitre studied samples, this alkaline lamprophyre is characterized by low SiO2 (35.6 wt%), ultrapotassic (K2O/Na2O = 5; K2O = 4.4 wt%) and peralkaline (PI = 1.3). It exhibits variable MgO content (14 wt%) and is enriched in REEs (∑REE=~1,300 ppm) and other trace elements (Nb, Ta, Zr, Hf, Sr, Ba). This lamprophyre is characterized by olivine and phlogopite phenocrysts set in a fine-grained groundmass of clinopyroxene, apatite, phlogopite, magnetite, chromite, and perovskite, with rare titanite and garnet; kalsilite is absent. Analyzing the trace elements of the main minerals in this lamprophyre helped us learn more about the origin and evolution of these magmas, as well as their possible genetic link with the other Salitre rocks. This analysis also provided important information about their enrichment in rare earth elements (REEs) and high field strength elements (HFSEs). This publication results from work conducted under the transnational access/national open access action at Mass spectrometry la-icp laboratory (IGG-CNR, Italy) supported by WP3 ILGE - MEET project, PNRR - EU Next Generation Europe program, MUR grant number D53C22001400005.

Compilation of global Archean and Paleoproterozoic sanukitoid geochemical data

Sanukitoids, also referred to as high-Mg diorites, are a distinctive type of igneous rock from the late Archean-early Proterozoic, and are characterised by enrichment in both compatible elements (e.g. Mg, Ni, Cr) and incompatible elements (e.g. Ba, Sr, light rare earth elements). Their geochemistry is typically interpreted as recording petrogenesis of their parental magmas via interaction between mantle peridotite and recycled crust-derived component (e.g. metabasite melts, sediment melts, aqueous fluids), and is often considered to be "transitional" between that of Archean sodic tonalite-trondhjemite-granodiorite (TTG) suites and post-Archean potassic granites. This dataset presents a global compilation of all Archean-Paleoproterozoic rocks that have been described as "sanukitoid" in published literature, and consists of over 3600 individual samples. Whole rock major and trace element concentrations, radiogenic isotope compositions and stable isotope compositions are compiled in the dataset alongside reported magmatic ages of the samples. The dataset is provided both as an Excel workbook divided by craton (file: 2025-003_Spencer-et-al_Sanukitoid-Compilation.xlsx) and as a single CSV file (file: 2025-003_Spencer-et-al_Sanukitoid-Compilation.csv). Sanukitoid magmatism has been described on almost every Archean craton globally. Most reported sanukitoid magmatism occurred during the late Mesoarchean-Neoarchean (2.95 - 2.5 Ga), with another peak in sanukitoid magmatism in the mid-Paleoproterozoic (2.2 - 2.0 Ga). Older sanukitoid occurrences dating back to the Paleoarchean (>3.2 Ga) are also described in the literature.

Trace element data obtained from main minerals in Salitre clinopyroxenite and dunite rocks (APIP, Brazil)

The Salitre intrusion, which is subdivided into Salitre I and Salitre II. It was dated to ~86-82 Ma by Sonoki and Garda (1988). It is part of the Alto Paranaíba Igneous Province (APIP, Fig. 1) in Brazil. The APIP is one of the largest ultrapotassic/carbonatitic/kimberlitic provinces in the world. The intrusion consists of lamproites, carbonatites, and one lamprophyre, as well as various intrusive cumulitic rocks. These rocks include perovskite-phlogopite dunites, phlogopite-perovskite clinopyroxenites (salitrites, s.l.), phlogopitites, phoscorites, and perovskitites. These rocks are characterized by variable enrichment of olivine, clinopyroxene, phlogopite, perovskite, oxides, apatite, and carbonate, as well as several accessory phases, such as baddeleyite and calzirtite. Their geochemical and petrological features are related to the variable amounts of these minerals. For this part of the project, we have analyzed the concentrations of trace elements in the primary minerals (clinopyroxene, phlogopite, garnet, perovskite, apatite and olivine) identified in three phlogopite-perovskite clinopyroxenites and one perovskite-phlogopite dunite. Analyzing the trace elements in these minerals helped us to better understand the differential settling of minerals within the Salitre magma chamber, and their possible genetic relationship with carbonatitic and lamprophyric rocks. These analyses also provided important information about the minerals' enrichment in rare earth elements (REEs) and high field strength elements (HFSEs). This publication results from work conducted under the transnational access/national open access action at Mass spectrometry la-icp laboratory (IGG-CNR, Italy) supported by WP3 ILGE - MEET project, PNRR - EU Next Generation Europe program, MUR grant number D53C22001400005.

Mineral trace element analysis of xenocrysts and xenoliths hosted in the Limeira I kimberlite (APIP, Brazil)

The Limeira I kimberlite (91±6 Ma; Guarino et al., 2013) is part of the Alto Paranaíba Igneous Province (APIP) and was emplaced in the southern part of the São Francisco Craton in Brazil. This Kimberlite contains macrocrysts and phenocrysts of olivine, resorbed phlogopite/ tetraferriphlogopite, Al-free magnetite, chromite, magnesian ilmenite, rutile, perovskite, monticellite, apatite, serpentine and carbonate. It also contains a suite of xenocrysts and xenoliths (among which we recall wehrlite, phlogopite-ilmenite-websterite, olivine-ilmenite-glimmerite, clinopyroxenites bearing potassic-richterite, chromite-monticellite-kalsilite xenoliths, rutile with priderite or perovskite reaction rims, magnesian chromian ilmenite with perovskite rims). In this part of the project, we analyzed the xenocryst minerals and the main minerals found in the xenoliths entrapped in the Limeira I kimberlite. Analyzing the trace element concentrations in these minerals, helped us to better understand the processes that may occur in the subcontinental lithospheric mantle beneath the Alto Paranaíba Igneous Province. These analyses also provided important information about the minerals' enrichment in rare earth elements (REEs) and high field strength elements (HFSEs). This publication results from work conducted under the transnational access/national open access action at Mass spectrometry la-icp laboratory (IGG-CNR, Italy) supported by WP3 ILGE - MEET project, PNRR - EU Next Generation Europe program, MUR grant number D53C22001400005.

Biogeochemischer Kreislauf ausgewählter potenziell schädlicher (Ultra-)Spurenmetalle (Tl, SEE) im Küstenbereich

Im Fokus des Projektes steht der Einfluss des organischen Stoffkreislaufs auf den biogeochemischen Kreislauf der (Ultra-)Spurenmetalle Thallium (Tl) und die Gruppe der Seltenen Erden Elemente (SEE) im Küstenbereich. Bisher wird davon ausgegangen, dass diese Metalle nicht von bio-assoziierten Prozessen beeinflusst werden. Aktuelle Studien weisen jedoch darauf hin, dass diese Metalle in hochproduktiven Küstengebieten in Verbindung mit organischen Stoffkreisläufen stehen und im organischen Stoffpool akkumuliert werden. Ein Umstand, welcher ihr Potenzial zur Schädigung von Küstenökosystemen deutlich macht. Bislang ist jedoch wenig darüber bekannt, wie diese Metalle mit welcher Fraktion des organischen Stoffpools in Verbindung stehen und welchen Einfluss organische Stoffkreisläufe auf deren biogeochemische Kreisläufe haben, und umgekehrt. Außerdem ist bislang nicht geklärt, welche Prozesse für die beobachteten räumlichen und zeitlichen Änderungen in den Konzentrationsmustern von Tl und SEE, insbesondere in den Küstengebieten, verantwortlich sind. In Anbetracht der Toxizität dieser Metalle, der anthropogenen Veränderung ihres Vorkommens im Küstenbereich, sowie ihrer Verwendung als Tracer für ozeanische Prozesse, sind Kenntnisse über ihre biogeochemischen Kreisläufe unerlässlich. Zentrale Aspekte, die im Rahmen dieses Projekts untersucht werden sollen, sind: (1) Das Verhalten und der Verbleib von natürlich und anthropogen eingetragenem Tl und SEE in den verschiedenen Kompartimenten des Küstenozeans, und (2) Der Einfluss von organischen Stoffkreisläufen, in Bezug auf die lebende und nicht lebende Fraktion des Stoffpools, auf die Konzentrationsmuster von Tl und SEE und umgekehrt.Diese Aspekte werden mittels eines höchst interdisziplinären Multiparameter-Ansatzes untersucht, in welchem labor- und feldbasierte Ansätze von unterschiedlicher ökologischer Komplexität und zeitlicher Auflösung kombiniert werden. Auf Basis eines Mikrokosmen-Ansatzes, in welchem eine für die Nordsee typische Phytoplanktongemeinschaft und repräsentative Einzelarten unter umgebungs- und erhöhten Tl- und SEE-Bedingungen inkubiert werden, werden die artspezifischen Auswirkungen auf das Verhalten von Tl und SEE und umgekehrt die Reaktion des Phytoplanktons auf anthropogenen Stress ermittelt. Der Einfluss einer Phytoplanktonblüte und den damit verbundenen biogeochemischen Prozessen auf die Metallkonzentrationen im intertidalen Küstenbereich sowie potenzielle Schlüsselfaktoren, werden im Rahmen eines Mesokosmen-Ansatzes untersucht. Die saisonale und interannuelle Variabilität der Tl- und SEE-Dynamik im Küstenbereich sowie die verantwortlichen Hauptfaktoren, werden anhand von Multiparameter-Zeitseriendaten, welche im Küstenbereich der deutschen Nordsee erhoben werden, untersucht. Anhand der Ergebnisse werden außerdem die Erkenntnisse aus den Mikro- und Mesokosmenkonzepten validiert und deren Übertragbarkeit auf ein natürliches System bewertet.

Innovative Kupferschlackenaufbereitung für die Rohstoffversorgung, Teilvorhaben 1: Chemische und Biochemische Laugungsmethoden

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