On the mass-to-light ratio of the local Galactic disc and the optical luminosity of the Galaxy     

Chris Flynn  Johan Holmberg  Laura Portinari  Burkhard Fuchs  Hartmut Jahreiß 《Monthly notices of the Royal Astronomical Society》2006,372(3):1149-1160

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OSL Age Determination of Archaeological Stone Structures Using Trapped Aeolian Sediments: A Case Study from the Negev Highlands,Israel     

Andrea Junge  Johanna Lomax  Ruth Shahack‐Gross  Zachary C. Dunseth  Israel Finkelstein  Markus Fuchs 《Geoarchaeology》2016,31(6):550-563

Optically stimulated luminescence (OSL) dating is widely applied to sediments in paleoenvironmental sciences. However, there are only limited examples determining the age of archaeological stone structures by OSL using dust deposits. The age of dust deposits associated with ancient buildings may be used to date the onset of settlement (sediment below structures), settlement activity (occupation layer), or the time after a settlement had been abandoned or destroyed (sediment between collapsed roofs and walls). In this study, OSL dating is applied to establish numerical dates for settlement structures situated in the Negev Highlands, Israel. Two archaeological sites are investigated to identify their occupation history, by dating nine samples of aeolian dust trapped within the remains of ancient buildings. The OSL dating technique is applied using coarse grain quartz and a standard single‐aliquot regenerative‐dose (SAR) protocol. It was possible to date the onset of sedimentation in a later phase of the human occupation or shortly after the sites were abandoned, to 3.7 ± 0.3 ka (Intermediate Bronze Age) at the central site and to 2.7 ± 0.2 ka (Iron Age) at the ephemeral site. These results are supported by archaeological evidence gained from pottery finds and the architecture of the ancient buildings.  相似文献   

Single-crystal structure and Raman spectroscopy of synthetic titanite analog CaAlSiO<Subscript>4</Subscript>F     

Hannes Krüger  Daniel M. Többens  Peter Tropper  Udo Haefeker  Volker Kahlenberg  Martin R. Fuchs  Vincent Olieric  Ulrike Troitzsch 《Mineralogy and Petrology》2015,109(5):631-641

Synthetic CaAlSiO₄F, the Al-F analog of titanite, has been investigated using single-crystal synchrotron diffraction experiments at Beamline X06DA (Swiss Light Source, Paul Scherrer Institute, Villigen, Switzerland) and Raman spectroscopy. The presented structural model with 40 parameters was refined against 506 unique reflections to a final R _{o b s} of 0.026 (space group A2/a, a = 6.9120(11), b = 8.5010(10), c = 6.435(2) Å, β = 114.670(11)°, and Z = 4) and exhibits less distorted coordination polyhedra than earlier models from powder data. Vibrational spectra were calculated in harmonic approximation at the Γ point from fully relaxed energy optimisations of the crystal structure, using 3D-periodic density functional theory with Gaussian basis sets and the software CRYSTAL06. The lattice parameters of the fully relaxed structure were in good agreement with the experimental values, with the calculated values 0.8 ± 0.4 % too large; the monoclinic angle was calculated 0.4° too large. The agreement of the calculated Raman frequencies with the observed ones was very good, with standard deviation ±3 cm^?1 and maximum deviations of ±7 cm^?1. Furthermore, a detailed discussion of the atomic displacements associated with each Raman mode is given.  相似文献   

Tectonic and climatic forcing on the rivers in Pamir     

Margret C. Fuchs  Richard Gloaguen 《International Journal of Earth Sciences》2013,102(7):2005-2006

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Spatiotemporal dynamics: the need for an innovative approach in mountain hazard risk management   总被引：5，自引：4，他引：1  

Sven Fuchs  Margreth Keiler  Sergey Sokratov  Alexander Shnyparkov 《Natural Hazards》2013,68(3):1217-1241

Starting with an overview on losses due to mountain hazards in the Russian Federation and the European Alps, the question is raised why a substantial number of events still are recorded—despite considerable efforts in hazard mitigation and risk reduction. The main reason for this paradox lies in a missing dynamic risk-based approach, and it is shown that these dynamics have different roots: firstly, neglecting climate change and systems dynamics, the development of hazard scenarios is based on the static approach of design events. Secondly, due to economic development and population dynamics, the elements at risk exposed are subject to spatial and temporal changes. These issues are discussed with respect to temporal and spatial demands. As a result, it is shown how risk is dynamic on a long-term and short-term scale, which has to be acknowledged in the risk concept if this concept is targeted at a sustainable development of mountain regions. A conceptual model is presented that can be used for dynamical risk assessment, and it is shown by different management strategies how this model may be converted into practice. Furthermore, the interconnectedness and interaction between hazard and risk are addressed in order to enhance prevention, the level of protection and the degree of preparedness.  相似文献   

Spatio-temporal aspects and dimensions in integrated disaster risk management   总被引：1，自引：1，他引：0  

Christoph Aubrecht  Sven Fuchs  Clemens Neuhold 《Natural Hazards》2013,68(3):1205-1216

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A structured approach to enhance flood hazard assessment in mountain streams   总被引：1，自引：0，他引：1  

B. Mazzorana  F. Comiti  S. Fuchs 《Natural Hazards》2013,67(3):991-1009

An evidence-based flood hazard analysis in mountain streams requires the identification and the quantitative characterisation of multiple possible processes. These processes result from specific triggering mechanisms on the hillslopes (i.e. landslides, debris flows), in-channel morphodynamic processes associated with sudden bed changes and stochastic processes taking place at critical stream configurations (e.g. occlusion of bridges, failure of levees). From a hazard assessment perspective, such possible processes are related to considerable uncertainties underlying the hydrological cause-effect chains. Overcoming these uncertainties still remains a major challenge in hazard and risk assessment and represents a necessary condition for a reliable spatial representation of process intensities and the associated probabilities. As a result of an accurate analysis of the conceptual flaws present in the procedures currently employed for hazard mapping in South Tyrol (Italy) and Carinthia (Austria), we propose a structured approach as a means to enhance the integration of hillslope, morphodynamic and stochastic processes into conventional flood hazard prediction for mountain basins. To this aim, a functional distinction is introduced between prevailing one-dimensional and two-dimensional process propagation domains, i.e., between confined and semi- to unconfined stream segments. The former domains are mostly responsible for the generation of water, sediment and wood fluxes, and the latter are where flooding of inactive channel areas (i.e. alluvial fans, floodplains) can occur. For the 1D process propagation domain, we discuss how to carry out a process routing along the stream system and how to integrate numerical models output with expert judgement in order to derive consistent event scenarios, thus providing a consistent quantification of the input variables needed for the associated 2D domains. Within these latter domains, two main types of spatial sub-domains can be identified based on the predictability of their dynamics, i.e., stochastic and quasi-deterministic. Advantages and limitations offered by this methodology are finally discussed with respect to hazard and risk assessment in mountain basins.  相似文献   

Optically stimulated luminescence dating of fluvioglacial (sandur) sediments from north-eastern Germany     

Christopher Lüthgens  Matthias Krbetschek  Margot Böse  Margret C. Fuchs 《Quaternary Geochronology》2010,5(2-3):237-243

This study presents first results of a project which aims to develop an absolute chronology of the Weichselian ice marginal positions in north-eastern Germany using Optically Stimulated Luminescence (OSL) dating. Owing to the special geomorphological and stratigraphical setting, many of the sampling sites were situated close to the former ice margin. At some sections the sediments showed an incomplete resetting of the OSL signal. For this study the representative sandur sediment section from the Beelitz outwash cone was chosen to elaborate a strategy to reliably detect insufficient bleaching and to choose an appropriate age model for the calculation of the true burial dose of each sample. The age determined for the formation of the Beelitz outwash cone is 34.1 ± 3.0 ka. Although this age might still be a maximum age, this study shows that by applying the proposed methodological strategy, plausible ages can be derived from insufficiently bleached, ice proximal sandur sediments.  相似文献   

A 20 ka sediment record from the Hajar Mountain range in N-Oman,and its implication for detecting arid–humid periods on the southeastern Arabian Peninsula     

Markus Fuchs  Andreas Buerkert 《Earth and Planetary Science Letters》2008,265(3-4):546-558

Playa-like sediments from the Hajar Mountain range in northern Oman (22.83°N, 59.00°E; 1050 m asl) document variations of the paleoenvironmental and paleoclimate conditions over the last 20 ka. Based on high-resolution sediment sampling and their OSL dating, sedimentation rates were calculated and used as a proxy for paleorainfall. The results show that the Glacial to Lateglacial was characterized by arid conditions with a following transitional period of even less rainfall. At 10.5 ka, sedimentation rates increases abruptly, indicating the onset of the early Holocene humid period (EHHP). Rainfall reaches its maximum at 9–8 ka (EHHP-2) and a decreasing sedimentation rate after 8 ka characterizes the arid period of the middle to late Holocene. Variations of the hydrological regime are associated with the intensity of the boreal summer Indian monsoon and its related position of the ITCZ. For the onset of the EHHP, a northerly shift of the ITCZ is postulated, thus confirming earlier results from the southern Arabian Peninsula.  相似文献   

Solar Eclipses and the Surface Properties of Water     

Fuchs  Elmar C.  Oudakker  Gerrit  Justinek  Martin  Dyer  Nigel  Woisetschläger  Jakob  Godines  Kevin  Mäder  Matthias  Freund  Friedemann T. 《Earth, Moon, and Planets》2019,123(1-2):15-43

Earth, Moon, and Planets - During four solar eclipse events (two annular, one total and one partial) a correlation was observed between a change in water surface tension and the magnitude of the...  相似文献