Floods of the Upper Danube River and Its Tributaries and Their Impact on Urban Economies (c. 1350–1600): The Examples of the Towns of Krems/Stein and Wels (Austria)

This paper examines the impact of disastrous and ‘ordinary’ floods on human societies in what is now Austria. The focus is on urban areas and their neighbourhoods. Examining institutional sources such as accounts of the bridge masters, charters, statutes and official petitions, it can be shown that city communities were well acquainted with this permanent risk: in fact, an office was established for the restoration of bridges and the maintenance of water defences and large depots for timber and water pipes ensured that the reconstruction of bridges and the system of water supply could start immediately after the floods had subsided. Carpenters and similar groups gained 10 to 20 per cent of their income from the repair of bridges and other flood damage. The construction of houses in endangered zones was adapted in order to survive the worst case experiences. Thus, we may describe those communities living along the central European rivers as ‘cultures of flood management’. This special knowledge vanished, however, from the mid-nineteenth century onwards, when river regulations gave the people a false feeling of security.

Melting of metasomatized peridotite at 4–6 GPa and up to 1200 °C: an experimental approach

The phase assemblages and compositions in a K-bearing lherzolite + H2O system are determined between 4 and 6 GPa and 850–1200 °C, and the melting reactions occurring at subarc depth in subduction zones are constrained. Experiments were performed on a rocking multi-anvil apparatus. The experiments had around 16 wt% water content, and hydrous melt or aqueous fluid was segregated and trapped in a diamond aggregate layer. The compositions of the aqueous fluid and hydrous melt phases were measured using the cryogenic LA-ICP-MS technique. The residual lherzolite consists of olivine, orthopyroxene, clinopyroxene, and garnet, while diamond (C) is assumed to be inert. Hydrous and alkali-rich minerals were absent from the run products due to preferred dissolution of K2O (and Na2O) to the aqueous fluid/hydrous melt phases. The role of phlogopite in melting relations is, thus, controlled by the water content in the system: at the water content of around 16 wt% used here, phlogopite is unstable and thus does not participate in melting reactions. The water-saturated solidus, i.e., the first appearance of hydrous melt in the K–lherzolite composition, is located between 900 and 1000 °C at 4 GPa and between 1000 and 1100 °C at 5 and 6 GPa. Compositional jumps between hydrous melt and aqueous fluid at the solidus include a significant increase in the total dissolved solids load. All melts/fluids are peralkaline and calcium-rich. The melting reactions at the solidus are peritectic, as olivine, clinopyroxene, garnet, and H2O are consumed to generate hydrous melt plus orthopyroxene. Our fluid/melt compositional data demonstrate that the water-saturated hybrid peridotite solidus lies above 1000 °C at depths greater than 150 km and that the second critical endpoint is not reached at 6 GPa for a K2O–Na2O–CaO–FeO–MgO–Al2O3–SiO2–H2O–Cr2O3(–TiO2) peridotite composition.

The behaviour of incompatible elements during hydrous melting of metasomatized peridotite at 4–6 GPa and 1000 °C–1200 °C

Trace element behavior during hydrous melting of a metasomatized garnet–peridotite was examined at pressures of 4–6 GPa and temperatures of 1000 °C–1200 °C, conditions appropriate for fluid penetrating the mantle wedge atop the subducting slab. Experiments were performed in a rocking multi-anvil apparatus using a diamond-trap setup. The compositions of the fluid and melt phases were measured using the cryogenic LA-ICP-MS technique. The water-saturated solidus of the K-lherzolite composition is located between 900 °C and 1000 °C at 4 GPa and between 1000 °C and 1100 °C at 5 and 6 GPa. The partition coefficients between fluid or melt and clinopyroxene reveal an asymmetric MREE trough with a minimum at Dy. The clinopyroxene in equilibrium with aqueous fluids is characterized by DUfluid–cpx > DThfluid–cpx while DUmelt–cpx tends to be similar to DThmelt–cpx. The partition coefficients between fluid or melt and garnet reveal very strong light to heavy REE fractionation, DLa/DLu from 95 (hydrous melt) to 1600 (aqueous fluid). The LILE are highly incompatible with partition coefficients > 50. The behavior of HFSE are decoupled, with DZr,Hf close to 1 while DNb,Ta > 10. Garnet is characterized by DUmelt/fluid–garnet < DThmelt/fluid–garnet. A comparison of our experimental partitioning results for trivalent cations as well as the results from the literature and the calculations carried out using the lattice strain model adapted to the presence of water in the bulk system indicates that H2O in the fluid or melt phase has a prominent effect on trace element partitioning. Garnet in mantle rocks in equilibrium with an aqueous fluid is characterized by significantly higher Do(3 +) for REE in the X site of the garnet compared with the partitioning values of the optimal cation in garnet in equilibrium with hydrous melts. Our data show for the first time that the change in the nature of the mobile phase (fluid vs. melt) does affect the affinities of trace elements into the garnet crystal at conditions below the second critical endpoint of the system. The same also applies for clinopyroxene, although this is less clear. Consequently, our new data allow for refinements in predictive modeling of element transfer from the slab to the mantle wedge and of possible compositions of metasomatized mantle that sources OIB magmatism.

Konsum und Kontrolle : wie Vitamin C zu einem Allheilmittel werden konnte

Künstliches Vitamin C ist heute ein Massenprodukt. Dass sich Ascorbinsäure seit ihrer Erfindung 1933 zu einem alltäglichen Konsumgut mausern konnte, ist weniger durch ihr medizinisches Potential zu erklären, sondern verdankt sich vielmehr einem dynamischen Zusammenspiel von Produktion, Vermarktung und Gesundheitspolitik. Der Beitrag fokussiert insbesondere auf die komplexen Interaktionen zwischen Gesundheitskonzepten, diagnostischen Instrumenten und ärztlichem Blick. Dabei scheinen nicht nur die Differenzen zwischen „rein naturwissenschaftlichen“ und „ärztlich-biologischen“ Standpunkten auf, sondern es zeigt sich auch, dass Nahrungsbestandteile immer auch gesundheitspolitisch und ethisch aufgeladen sind.

Miocene Mediterranean Nd, Sr, C and O isotope composition

Isotopic compositions of marine sediments and fossils have been investigated from northern basins of the Mediterranean to help constrain local oceanographic and climatic changes adjacent to the uplifting Alps. Stable C and O isotope compositions of benthic and planktonic foraminifera from the Umbria-Marche region (UMC) have an offset characteristic for their habitats and the changes in composition mimic global changes, suggesting that the regional conditions of climate and the carbon cycle were controlled by global changes. The radiogenic isotope composition of these fossil assemblages allows recognition of three distinct periods. In the first period, from 25 to 19 Ma, high epsilon-Nd values and low 87Sr/86Sr of sediments and fossils support intense tectonism and volcanism, related to the opening of the western Mediterranean. In the second period, from 19 to 13 Ma the 87Sr/86Sr ratio of Mediterranean (UMC) deviate from the global ocean, which is compatible with rapid uplift of the hinterland and intense influx of Sr from Mesozoic carbonates of the western Apennines. This local control on the seawater was driven by a humid and warm climate and indicates restricted exchange of water with the global ocean. Generally, the epsilon-Nd values of the fossils are very similar to those of Indian Ocean water, with brief periods of a decrease in the epsilon-Nd values coinciding with volcanic events and maybe sea level variation at 15.2 Ma. In the third period, from 13 to 10 Ma the fossils have 87Sr/86Sr similar to those of Miocene seawater while their epsilon-Nd values change considerably with time. This indicates fluctuating influence of the Atlantic versus the Paratethys and/or locally evolved seawater in the Mediterranean driven by global sea level changes. Other investigated localities near the Alps and from the ODP 900 site are compatible with this oceanographic interpretation. However, in the late early Miocene, enhanced local control, reflecting erosion of old crustal silicate rocks near the Alps, results in higher 87Sr/86Sr.

Discarge compilation from The Global River Discharge (RivDIS) Project

The Global River Discharge (RivDIS) data set contains monthly discharge measurements for 1018 stations located throughout the world. The period of record varies widely from station to station, with a mean of 21.5 years. These data were digitized from published UNESCO archives by Charles Voromarty, Balaze Fekete, and B.A. Tucker of the Complex Systems Research Center (CSRC) at the University of New Hampshire. River discharge is typically measured through the use of a rating curve that relates local water level height to discharge. This rating curve is used to estimate discharge from the observed water level. The rating curves are periodically rechecked and recalibrated through on-site measurement of discharge and river stage.