The Wolfsberg lithium deposit in Austria is one of the largest Li-Cs-Ta pegmatite resources in Europe. The deposit is part of the Austroalpine Unit Pegmatite Province in the Eastern Alps that formed ...during the high-temperature, low-pressure Permian extensional event and was subsequently overprinted by Cretaceous eclogite-facies metamorphism during the Alpine orogeny. The two pegmatite types distinguished at the deposit, amphibolite hosted-(AHP) and mica schist hosted-(MHP) pegmatite, consist of quartz, albite, K-feldspar, muscovite and spodumene with accessory apatite, beryl and columbite. Both pegmatite types have similar peraluminous granitic compositions and element distribution patterns. However, the AHP contains higher Li and Cs concentrations. Both pegmatite types display LREE-enriched/HREE-depleted chondrite-normalized REY patterns that suggest derivation from partial melting of basement mica schist during the Permian HT/LP extensional event. The Alpine metamorphism more strongly affected the MHP relative to the AHP, resulting in recrystallization of primary assemblages by metamorphic assemblages with lower rare-metal concentrations, and development of a strong foliation, during which (re)mobilized elements (e.g., Li, Cs) were concentrated along localized shear zones. Recognition of element remobilization in MHP associated with metamorphic overprinting may bear important implications towards mineral exploration for Li-Cs-Ta pegmatite in other strongly metamorphosed terranes.
ABSTRACT
Polymetamorphic garnet micaschists from the Austroalpine Saualpe Eclogite Unit (Kärnten, Austria, Eastern Alps) display complex microstructural and mineral–chemical relationships. Automated ...scanning electron microscopy routines with energy dispersive X‐ray (EDX) spectral mapping were applied for monazite detection and garnet mineral–chemical characterization. When the Fe, Mg, Mn and Ca element wt% compositions are used as generic labels for garnet EDX spectra, complex zonations and porphyroblast generations can be resolved in complete thin sections for selective electron‐microprobe analyses. Two garnet porphyroblast generations and diverse monazite age populations have been revealed in low‐Ca and high‐Al‐metapelites. Garnet 1 has decreasing Mn, constant Ca and significantly increasing Mg from cores to rims. Geothermobarometry of garnet 1 assemblages signals a crystallization along a M1 prograde metamorphism at ~650 °C/6–8 kbar. Sporadic monazite 1 crystallization started at c. 320 Ma. Subsequent pervasive 300–250 Ma high‐Y and high‐Gd monazite 1 formation during decompression coincided with the intrusion of Permian and Early Triassic pegmatites. Monazite 1 crystallized along the margin of garnet 1. Coronas of apatite and allanite around the large 320–250 Ma monazite signal a retrogressive stage. These microstructures suggest a Carboniferous‐to‐Early‐Permian age for the prograde M1 event with garnet 1. Such a M1 event at an intermediate‐P/T gradient has not yet been described from the Saualpe, and preceded a Permo‐Triassic low‐P stage. The M2 event with garnet 2 postdates the corona formation around Permian monazite. Garnet 2 displays first increasing XCa at decreasing XMg, then increasing XCa and XMg, and finally decreasing XCa with increasing XMg, always at high Ca and Mg, and low Mn. This records a P–T evolution which passed through eclogite facies conditions and reached maximum temperatures at ~750 °C/14 kbar during decompression‐heating. A monazite 2 population (94–86 Ma) with lower Y and Gd contents crystallized at decreasing pressure during the Cretaceous (Eo‐Alpine) metamorphism M2 at a high‐P/T gradient. The Saualpe Eclogite Unit underwent two distinct clockwise metamorphic cycles at different P–T conditions, related to continental collisions under different thermal regimes. This led to a characteristic distribution pattern of monazite ages in this unit which is different from other Austroalpine basement areas.
The monitoring of bedload transport processes in rivers is a still challenging task in research and the parameter effective transport width (ETW) allows, for the first time, a process description of ...the local variability of the bedload transport. In this paper, the distribution of bedload transport over a river cross-section was studied by statistically analyzing long-term monitoring data. Using an innovative integrated measurement system, combining geophones distributed over the river width with bedload traps and basket sampling, allows for continuous, high-resolution, long-term monitoring data of bedload transport characteristics to be generated. Geophone data can be used to record and describe bedload transport processes such as intensity, temporal variability, and local variability. One parameter observed was the ETW, which describes the width where bedload transport is taking place for different discharge classes in gravel bed rivers. With the help of a data series recorded over more than a decade, it is now possible, for the first time, to statistically describe the continuously and directly measured ETW. Hence, it became evident that the effective bedload transport width depends on the discharge rate and local transport capacity, and that bedload transport over the entire river width only occurs at high flows that prevail a few days a year.
Biochar (BC) as soil amendment has the potential to support the remediation of polluted soils. The aim of our study was to test metal extractability in a contaminated soil and metal accumulation in ...plants in response to the application of BC and compost-based and inorganic soil amendments. The soil used in our study was taken from a long-term polluted site in Austria (Arnoldstein). The treatments included three BC/compost mixtures (50/50
w
/
w
; using three different BC types), two inorganic amendments (gravel sludge (GS) with siderite-bearing (Fe) material (GSFe, 50/50
w
/
w
) and lime (L)) and an unamended control; each treatment consisted of 1.5 % in 1.2 kg soil. Poplar biochar (P-BC), GSFe and L significantly decreased the NH
4
NO
3
-extractable fraction of Pb, Zn and Cd, but not of Cu. The highest immobilisation effect within the organic amendments was found after P-BC, reducing NH
4
NO
3
-extractable Zn by 63 %. In contrast to the NH
4
NO
3
extractions, heavy metal concentrations in the aboveground plant material (shoots of
Lolium multiflorum
) did not generally decrease. Still, Cd, Ni and Zn concentrations in
L. multiflorum
grown on the amended soil were lower after the P-BC treatment. Cu and Pb showed slightly higher plant concentrations upon amendment addition, indicating that NH
4
NO
3
extractions did not entirely reflect plant availability. Our data show that the type of BC and the addition of compost are crucial when using sorbent additives as a remediation strategy for metal-polluted soils and that the desired immobilisation effects cannot be achieved for all heavy metals. Depending on the type of metal, specific biochars and compost mixtures can either cause immobilisation or mobilisation.
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•Newly-discovered earliest Devonian amphibolites in the Saualpe basement, Eastern Alps.•Magma formed in a slab window environment associated with mid-ocean ridge subduction.•The ...opening of the West Paleo-Tethys Ocean happened during Late Silurian–earliest Devonian.
The timing of the opening of the West Paleo-Tethys Ocean in Eastern Alps remains unclear. To constrain this event, we present new zircon U-Pb ages, Hf isotopic compositions, and whole-rock major- and trace-element data for the meta-mafic rocks (amphibolites) in the southern and western Saualpe crystalline basement, Eastern Alps. Zircon U-Pb dating of three samples yield crystallization ages of 418 ± 6 Ma, 417 ± 3 Ma and 415 ± 3 Ma, indicating that they formed during the earliest Devonian. Geochemically, these meta-mafic rocks have relatively low SiO2 and MgO contents and high TiO2 contents. They are enriched in light rare earth elements (LREE), particularly in Nb and Ta, and show relatively flat heavy rare-earth elements (HREE) patterns, suggesting that they have affinities with the alkaline oceanic island basalts (OIB). The geochemical characteristics, together with the positive εHf(t) values of 0.7–11.1, imply that the OIB-like meta-mafic rocks originated from partial melting of a lherzolite source including spinel and garnet. The primary magma shows complex sources involving asthenospheric, lithospheric mantle and subducted slab components, which was subsequently modified by crustal contamination. This reveals that the magma formed in a slab window environment associated with mid-ocean ridge subduction. The contemporaneous OIB-like alkaline amphibolites were also found in the Central Austroalpine basement and in Northwestern Turkey. We suggest that the Late Silurian–earliest Devonian OIB-like magmatism is related to a back-arc extension setting along the northern margin of Gondwana leading to the separation of the European Hunic terranes and hence placing age constraints on the opening of the West Paleo-Tethys Ocean.
An ongoing investigation of the middle Miocene (Sarmatian) palynoflora from the Lavanttal Basin continues to show that it contains an extremely rich assemblage of angiosperm taxa. The Fagales to ...Rosales pollen record documented here contains 34 different taxa belonging to the Betulaceae (Alnus, Betula, Carpinus, Corylus, Ostrya), Fagaceae (Castanea, Fagus, Quercus Groups Cerris, Ilex, Cyclobalanopsis, Quercus/Lobatae), Juglandaceae (Engelhardioideae, Carya, Juglans, Pterocarya), Myricaceae (Morrella vel Myrica), Cannabaceae (Celtis), Elaeagnaceae (Elaeagnus), Rhamnaceae, Rosaceae (Prunus) and Ulmaceae (Cedrelospermum, Ulmus, Zelkova). Two of the pollen types represent extinct genera, Trigonobalanopsis and Cedrelospermum, and are also reported for the first time from the Lavanttal Basin along with pollen of Rhamnaceae and Prunus. The different types of Quercus pollen are now affiliated with Groups Cerris, Cyclobalanopsis, Ilex and Quercus/Lobatae based on sculpturing elements observed using scanning electron microscopy (SEM). Köppen signatures of potential modern analogues of the fossil Fagales and Rosales suggest a subtropical (Cfa, Cwa) climate at lower elevation and subsequent subtropical to temperate climate with altitudinal succession (Cfa → Cfb/Dfa→ Dfb; Cwa → Cwb → Dwb) in the Lavanttal area during accumulation of the palynoflora. Most of the fossil taxa have potential modern analogues that can be grouped as nemoral and/or merido-nemoral vegetation elements, and the diversity of Fagales indicates a varying landscape with a high variety of niches.
The end of the First World War and the long transformation from the Great War to the consequent borderland conflicts came into the centre of academic interest in the last few years. Many studies have ...been expanding the horizon of the research to the Central and Eastern European states and their borderland struggles of 1918-1920. One of these 'pygmies' wars was the so called Kärntner Abwehrkampf, fought between the South Slavic and Austrian forces for the southern parts of Carinthia. Although the hostilities played a pivotal role in the German and Austrian right-wing paramilitary mythologies in the interwar period, the history of the war is still relatively underresearched. This article investigates one particular aspect of the conflict, namely the way how Austrian soldiers were remobilized in the province during the first phase of the struggle. The study aims to challenge the existing, often oversimplified explanations about the servicemen's social background and their motivation to serve in the army. In order to provide a complex picture about the recruitment, the paper presents the three most important narrative traditions on the war and contrasts their claims with the statistical analyses of the soldiers' enlistment records. The study intends to prove that the political explanations of the memoire literature(s) about the people motivation to fight are largely - although not entirely - misleading. Moreover, the analyses provide a new understanding about the recruitment through pointing out the unique characteristics how people were mobilized during the conflict.
The formation of dental caries is mainly caused by dietary habits and therefore, may contain information for dietary reconstructions of fossil hominids. This study investigates the caries lesion in ...the 12.5 Ma old type specimen of Dryopithecus carinthiacus Mottl 1957 (Primates, Hominidae) from St. Stefan (Austria). Potential food sources are identified on associated palynological data, which allow conclusions about food quality, sugar availability and the hominid metabolism during the Middle Miocene. Using micro computed tomography (μCT) and scanning electron microscopy (SEM) we provide a detailed analysis and characterization of the individuals' caries type. Its lesion is compared with a dataset of 311 wild chimpanzees, indicating morphological and etiological differences in caries formation between both species. The affected molar of D. carinthiacus reveals features known from severe dental caries in humans: (1) Cavitation with steep walls and smooth surface; (2) Reparative dentine at the roof of the pulp chamber; (3) Sclerotic dentine below the cavitation; (4) Association with dental calculus and (5) Unilateral usage of the healthy right tooth row. Its advanced primary caries, initiating on the intact enamel surface, indicates a frequent intake of highly cariogenic sugar-rich fruits, which likely exceeds the frugivory of extant chimpanzees. This finding corresponds with the associated palynological record, which infers a habitat with nearly year-round supply (9-10 months/year) of high quality foods (>carbohydrates; < fibers). Our conclusions challenge the model of a step-wise increase in dietary quality during hominid evolution and support the uricase hypothesis, which discusses the hominid autapomorphy of a fructose-based fat accumulation for periods of starvation. This model receives further validation by the identification of soft-tissue preservation, interpreted as fossilized white adipose cells, in the articulated hominid skeleton of Oreopithecus bamboli from Italy.
The Carboniferous is characterized by drastic climatic and environmental fluctuations, which include multiple phases of glaciation resulting in an icehouse climate. Additionally, dynamic continental ...reconfigurations forced the contraction of the Rheic Ocean resulting in the closure of the Rheic–Tethyan Gateway, which precluded further faunal exchanges between the North American and Eurasian marine realms. Interestingly, cartilaginous fishes seem to be relatively immune to these drastic climatic and environmental changes. The Eurasian fossil record of Paleozoic sharks is strongly biased towards intensively sampled localities from England, Ireland, Scotland, and the Russian Platform. Here we present rare dental material from the Serpukhovian (early Carboniferous) of Austria, adding new information to the paleogeographic distribution of ctenacanthiform sharks. The new material revealed the first record of the genus Saivodus in Central Europe and allowed us to recognize a new species, Cladodus gailensis sp. nov., and a remnant of fossilized cartilage. In an attempt to identify possible linkages between climatic or environmental fluctuations on shark diversity throughout the Carboniferous, we provide a synopsis of the distribution and diversity of elasmobranchs based on primary literature. This preliminary assessment at genus level indicates two pronounced events of extinction, with the first one occurring during the latest Mississippian and the second one towards the end of the Pennsylvanian. The first extinction event distinctly correlates with the known diversity decline of other marine inhabitants and the second occurred during an unstable period of multiple phases of glaciation.
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