Seismotectonics investigations in the internal Cottian Alps (Italian Western Alps)

NASA Astrophysics Data System (ADS)

Perrone, Gianluigi; Eva, Elena; Solarino, Stefano; Cadoppi, Paola; Balestro, Gianni; Fioraso, Gianfranco; Tallone, Sergio

2010-05-01

The inner Cottian Alps represent an area of a low- to moderate- magnitude seismicity (Eva et al., 1990) even though some historical earthquakes reached VIII degree of the Mercalli's scale. Although the frame of seismicity is quite well known, the relation between faults and earthquake sources is still under debate. The low deformation rates and the occurrence of several glacial-interglacial cycles during the Pleistocene partly masked the geomorphological evidences of the recent tectonic activity. Recent studies based on field mapping and structural analysis (Balestro et al., 2009; Perrone et al., 2009) allowed characterizing the size and extension of the regional-scale faults dissecting this area of the Western Alps. Here, we combine the results of these novel studies and updated seismological data with the aim to investigate the relations between mapped faults and seismic activity. In the analyzed area both continental crust and oceanic tectonic units, belonging to the Penninic Domain of the Western Alps, crop out. The main brittle tectonic feature of this area is represented by the Lis-Trana Deformation Zone (LTZ), an N-S striking, steep structure that extends for about 35 km from the Lower Lanzo valleys to the Lower Sangone Valley. The occurrence of steep faults displacing the metamorphic basement, showed in seismic sections carried out for oil exploration (Bertotti & Mosca, 2009), suggests that the LTZ may be prolonged Southward beneath the Plio-Quaternary deposits of the Po Plain. West of the LTZ some other minor E-W and N-S faults are also present. Zircon and apatite fission-track data indicate that the activity of these faults started since the Oligocene. Two main faulting stages characterize the post-metamorphic structural evolution of this area: the earlier (faulting stage A; Oligocene?-Early Miocene?) is associated to right-lateral movements along the LTZ and sinistral movements along E-W faults; the subsequent faulting stage (faulting stage B; post

Isotopic composition of sulfate accumulations, Northern Calcareous Alps, Austria

NASA Astrophysics Data System (ADS)

Bojar, Ana-Voica; Halas, Stanislaw; Bojar, Hans-Peter; Trembaczowski, Andrzej

2015-04-01

The Eastern Alps are characterised by the presence of three main tectonic units, such as the Lower, Middle and Upper Austroalpine, which overlie the Penninicum (Tollmann, 1977). The Upper Austroalpine unit consists of the Northern Calcareous Alps (NCA) overlying the Greywacke zone and corresponding to the Graz Paleozoic, Murau Paleozoic and the Gurktal Nappe. Evaporitic rocks are lacking in the later ones. The Northern Calcareous Alps are a detached fold and thrust belt. The sedimentation started in the Late Carboniferous or Early Permian, the age of the youngest sediments being Eocene. The NCA are divided into the Bajuvaric, Tirolic and Juvavic nappe complexes. The evaporitic Haselgebirge Formation occurs in connection with the Juvavic nappe complex at the base of the Tirolic units (Leitner et al., 2013). The Haselgebirge Formation consists mainly of salt, shales, gypsum and anhydrite and includes the oldest sediments of the NCA. The age of the Haselgebirge Formation, established by using spors and geochronological data, is Permian to Lower Triassic. For the Northern Calcareous Alps, the mineralogy of sulphate accumulations consists mainly of gypsum and anhydrite and subordonates of carbonates. The carbonates as magnesite, dolomite and calcite can be found either as singular crystals or as small accumulations within the hosting gypsum. Sulfides (sphalerite, galena, pyrite), sulfarsenides (enargite, baumhauerite) and native sulphur enrichments are known from several deposits (Kirchner, 1987; Postl, 1990). The investigated samples were selected from various gypsum and halite rich deposits of the Northern Calcareous Alps. A total of over 20 samples were investigated, and both oxygen and sulfur isotopic composition were determined for anhydrite, gyps, polyhalite, blödite and langbeinite. The sulfur isotopic values vary between 10.1 to 14 ‰ (CDT), with three values higher than 14 ‰. The Oxygen isotopic values show a range from 9 to 23 ‰ (SMOW). The sulfur

Magnetic fabric of fault breccia: Revealing the direction of the Cretaceous nappe-stacking in the Inner Western Carpathians by AMS analyses

NASA Astrophysics Data System (ADS)

Pomella, Hannah; Kövér, Szilvia; Fodor, László

2017-04-01

The anisotropy of magnetic susceptibility (AMS) has been recognized as a highly sensitive indicator of rock fabric and is widely employed in the field of structural geology. Brittle faults are often characterized by fault breccia, fault rocks with clast-in-matrix textures. A noteworthy feature of the breccia is the presence of a fabric defined by the preferred orientation of clasts and grains in the matrix. However, this fabric is often not visible in the field or in thin sections but can be detected by AMS analyses. The sample area of the present study is located within the Cretaceous thin-skinned nappe-system of the Inner Western Carpathians. This Alpine-type orogenic belt is built up by large-scale, few km thick nappes without connection to their root areas. These thin rock slices thrust over large distances without sign of mayor deformation within the nappe slice. All the deformation took place along highly strained, narrow shear zones lubricated by hot fluids. These hydrostatically pressurized zones develop on the bases of the nappes, where basal tectonic breccia was formed. Newly formed, syn-kinematic minerals are growing from the overpressured fluids. These polymict breccias have typical block-in-matrix texture with clast size vary between mm and few cm. The matrix is mainly submillimetre-scale rock fragments and cement. In spite of detailed studies about the physical conditions of nappe movements, there is no information about the tectonic transport direction. Analyses of brittle fault kinematics within the different tectonic slices suggest either NW-SE or N-S compressional stress field during the nappe-stacking. With this study we want to test if the magnetic fabric of tectonic breccia can help to determine the transport direction. The first results are very promising: Area 1 (basal tectonic breccia from Tisovec): the magnetic lineation is well defined and plunges gently towards N-NNW. The stretching lineation observable in the field within the uppermost

Topography of the Central Alps in the light of Tertiary collisional tectonics

NASA Astrophysics Data System (ADS)

Rosenberg, Claudio; Garcia, Sebastian

2013-04-01

Collisional shortening in the Central Alps is partitioned very differently between the upper and lower plates along the strike of the orogen. North of the Insubric Line, the amount of post-nappe shortening accommodated in the wedge of accreted lower crustal material, increases westwards, whereas south of the Insubric Line, post-nappe shortening accommodated in the upper plate increases eastward (Rosenberg and Kissling, 2013). Taking the Bergell pluton as a time marker, the age of these deformations is inferred to be post 30 Ma. We investigate the present-day topography of the Central Alps, in order to test whether the systematic, along-strike changes, in the amounts of post-nappe shortening are associated to a systematic change in the topographic signature. In order to do so, the maximum and minimum elevations, and the local relief along a series of N-S sections are analysed and compared. The analysis of these topographic sections shows that the local relief varies following two along-strike trends: 1. North of the Insubric Line, i.e. in the wedge of accreted lower crust, the relief decreases from west to east, showing the transition from a highly incised topography in the west to a plateau-like topography in the East. 2. South of the Insubric Line, i.e. in the lower plate, the relief increases from East to West. These trends point to a positive correlation between the amount of shortening and the intensity of local relief. Linear correlations between local relief and uplift rate (e.g. Hurtez et al., 1999), and between local relief and shortening rates (Champagnac et al., 2012) have been inferred for different, tectonically active areas. Areas of larger finite shortening in the Central Alps, characterized by higher local relief, probably correspond to areas of higher shortening (and uplift) rates during Alpine collision. Considering the very slow, present-day, convergent movements across the Central Alps (Noquet and Calais, 2004) it is not clear whether the

Episodic exhumation and relief growth in the Mont Blanc massif, Western Alps from numerical modelling of thermochronology data

NASA Astrophysics Data System (ADS)

Glotzbach, C.; van der Beek, P. A.; Spiegel, C.

2011-04-01

The Pliocene-Quaternary exhumational and topographic evolution of the European Alps and its potential climatic and tectonic controls remain a subject of controversy. Here, we apply inverse numerical thermal-kinematic modelling to a spatially dense thermochronological dataset (apatite fission-track and (U-Th)/He) of both tunnel and surface samples across the Mont Blanc massif in the Western Alps, complemented by new zircon fission-track data, in order to better quantify its Neogene exhumation and relief history. Age-elevation relationships and modelling results show that an episodic exhumation scenario best fits the data. Initiation of exhumation in the Mont Blanc massif at 22 ± 2 Ma with a rate of 0.8 ± 0.15 km/Myr is probably related to NW-directed thrusting during nappe emplacement. Exhumation rates decrease at 6 ± 2 Ma to values of 0.15 ± 0.65 km/Myr, which we interpret to be the result of a general decrease in convergence rates and/or extensive exposure of less erodible crystalline basement rocks from below more easily erodible Mesozoic sediments. Finally, local exhumation rates increase up to 2.0 ± 0.6 km/Myr at 1.7 ± 0.8 Ma. Modelling shows that this recent increase in local exhumation can be explained by valley incision and the associated increase in relief at 0.9 ± 0.8 Ma, leading to erosional unloading, isostatic rebound and additional rock uplift and exhumation. Given the lack of tectonic activity as evidenced by constant thermochronological ages along the tunnel transect, we suggest that the final increase in exhumation and relief in the Mont Blanc massif is the result of climate change, with the initiation of mid-Pleistocene glaciations leading to rapid valley incision and related local exhumation.

The Origin of The Piz Terri-Lunschania zone (Central Alps, Switzerland)

NASA Astrophysics Data System (ADS)

Galster, Federico; Stockli, Daniel

2017-04-01

The Piz Terri-Lunschania zone (PTLZ) represents a band of metasedimentary rocks embedded in a crucial knot at the NE border of the Lepontine dome, at the intersection of the Gotthard, Lucomagno, Simano, Adula and Grava nappes. Its origin and its position in the tectonostratigraphy of the Central Alps are still not completely understood. A better understanding of this sedimentary zone and its tectonic position could shed lights on the Helvetic-Penninic connection and facilitate the disentanglement of the Lepontine dome tectonics. In this study we combine structural and stratigraphic observations with detrital zircon (DZ) and detrital rutile (DR) U-Pb geochronology as well as mineral trace element data from Permian, Triassic and Jurassic sandstones. We compare these data with those from adjacent tectonic units and coeval strata in other portions of the Alpine chain. Maximal depositional ages, abrupt changes in provenances and stratigraphic correlations based on new DZ and DR U-Pb and trace element data allow for a better understanding of the sedimentary evolution of the Terri basin and its palaeogeographic position along the northern margin of the Alpine Tethys. In particular the DZ U-Pb signatures, with its abundant 260-280 Ma zircons and the scarcity of 290-350 Ma zircons, corroborates an Ultra-Adula origin of the PTLZ as proposed by Galster et al (2010; 2012) based on stratigraphic arguments and reinforces the notion of a Briançonnais influence on the stratigraphic record of this complex zone, a fact that has important tectonic and Palaeogeographic implications. Galster F, Cavargna-Sani M, Epard J-L, Masson H (2012) New stratigraphic data from the Lower Penninic between the Adula nappe and the Gotthard massif and consequences for the tectonics and the paleogeography of the Central Alps. Tectonophysics 579:37-55. doi: 10.1016/j.tecto.2012.05.029 Galster F, Epard J-L, Masson H (2010) The Soja and Luzzone-Terri nappes: Discovery of a Briançonnais element below the

Lower Oligocene Alpine geodynamic change: tectonic and sedimentary evidences in the western arc

NASA Astrophysics Data System (ADS)

Dumont, T.; Rolland, Y.; Simon-Labric, T.

2009-04-01

The formation of the western Alpine arc started during the earliest Oligocene, after a drastic kinematic change in the collisional regime. (A) Previously, south-southeast dipping subduction of the European lithosphere (including Briançonnais) underneath Adria resulted in an underfilled flexural basin propagating towards the north-northwest on the European foreland, which had already been moderately deformed due to the Iberian microplate motion. This propagation appears consistent with the Africa-Europe relative motion (Rosenbaum et al., 2002). During this early stage of collision, some oceanic units were obducted over the southern part of European continent (Corsica, Briançonnais). (B) From the early Oligocene on, the western Alps kinematics were dominated by lateral (westward) escape of the Internal Alps indenter, whose displacement with anticlockwise rotation progressively formed the arc. The structures of this mature stage of collision crosscut the buildup issued from (A), and its kinematics were probably more driven by local lithospheric forces of the Mediterranean domain (Jolivet et al., 1999) than by Africa-Europe convergence. The western and southern parts of the western Alpine arc display many evidences for this major syn-collisional change: - Structural interferences are found at various scales. For example, the circular-shape Pelvoux massif resulted in part from crossed shortening stages (SE-NW and E-W; Dumont et al., 2008). It is located in the footwall of two nappes stacks having propagated northwestwards and west- to southwestwards, respectively. The latter crosscuts the former south of Briançon city. - Tectonic transport directions are strongly variable both in the external and in the internal zones, but they consistently display anticlockwise rotation through time. The most important changes are found in the southern part of the western Alps, giving birth to a radial distribution propagating into the external zone. - Instead of beeing gradual, the

Low temperature thermochronology in the Easter Alps. New data, interpretations and perspectives.

NASA Astrophysics Data System (ADS)

Wölfler, Andreas

2015-04-01

The aim of this study is to evaluate new and published low temperature thermochronological data of the Eastern Alps in terms of its Mesozoic and Cenozoic tectonic evolution and the possible connection with deep seated lithospheric processes. In the Eastern Alps, the tectonic units that originate from the Penninic domain are buried beneath the Austroalpine nappe stack. Overthrusting of the Austroalpine nappes over the Penninic units occurred throughout the Cretaceous and lasted until the Eocene. During lateral tectonic extrusion in Oligocene to Miocene times the footwall penninic units exposed in the Tauern Window, were tectonically exhumed from below the Austroalpine hanging wall. This is well documented by Miocene to Pliocene zircon- and apatite fission track (ZFT, AFT) and (U-Th)/He data. However, the Austroalpine hanging wall shows a more complex age pattern. Late Cretaceous ZFT data reflect post-metamorphic exhumational cooling after Eo-Alpine metamorphism that goes along with an extensional phase that affected large parts of the Eastern Alps. Paleogene AFT and apatite (U-Th)/He data of the Austroalpine units to the east of the Tauern Window reflect exhumation of this area that supplied clastic material, the so-called Augenstein formation. Exhumation and erosion of the area left a probably hilly surface in Early Miocene times that was only moderately uplifted since then. These areas are well known for paleosurfaces exposed in the Gurktal- Kor- and Seckauer Alps to the east of the Tauern Window and in the central and eastern Northern Calcareous Alps. However, distinct parts of the Austroalpine hanging wall experienced substantial exhumation and surface uplift in the Miocene, contemporaneous to the exhumation of Penninic units and lateral extrusion of the Eastern Alps. These areas are restricted to the south and northeast of the Tauern Window and are characterized by steep and rugged reliefs that contrast the hilly and moderately shaped reliefs of the

Three-dimensional geometry and tectonostratigraphy of the Pennine zone, Central Alps, Switzerland and Northern Italy

NASA Astrophysics Data System (ADS)

Maxelon, Michael; Mancktelow, Neil S.

2005-08-01

Continental collision during Alpine orogenesis entailed a polyphase deformation history (D 1-D 5) in the Pennine zone of the Central Alps. The regional tectonostratigraphy was basically developed during D 1 and D 2, characterised by isoclinal, typically north-closing recumbent anticlines, separated by pinched-in synclines, on the scale of tens of kilometres. Later deformation phases (D 3 and D 4) warped the stack into wavy to open folds. Exhumation of this zone resulted locally in later vertical shortening and folding of already steep fabrics (D 5). Three-dimensional models of the nappe pile were constructed, based on geostatistical assessment of the regional foliation field and considering the abundant structural field data. These models indicate the existence of five principal tectonostratigraphic levels developed during D 1 and thus equivalent to nappe units s. str.: the Gotthard, the Leventina-Antigorio, the Maggia-Simano (and probably the Monte Leone as well as the Composite Lepontine Series), Lebendun-Soja and Adula-Cima Lunga levels. All these tectonic units formed part of the passive continental margin of Europe prior to the onset of the Alpine orogenesis. Individual isoclinal post-nappe folds reflect relative displacements on the order of 40 km or more. The most prominent D 2 post-nappe structure is the Wandfluhhorn Fold, structurally equivalent to the northern closure of the Leventina-Lucomagno Antiform. The Lebendun and Monte Leone folds are of similar magnitudes and also affect the whole nappe pile, whereas the smaller Mogno and Molare synforms only refold the Maggia-Simano nappe internally. Principal D 3 and D 4 structures are the tight Mergoscia Synform directly north of the Insubric Fault between Bellinzona and Locarno (Southern Steep Belt), the Maggia Steep Zone, forming the steep western limb of the Campo Tencia Synform and subdividing the Lepontine dome into the Simplon and Ticino subdomes, the Chiéra Synform steepening the dominant foliation in

The continental Etirol-Levaz slice (Western Alps, Italy): Tectonometamorphic evolution of an extensional allochthon

NASA Astrophysics Data System (ADS)

Ewerling, Kathrin; Obermüller, Gerrit; Kirst, Frederik; Froitzheim, Nikolaus; Nagel, Thorsten; Sandmann, Sascha

2013-04-01

suggest that the ELS experienced two independent stages of high-pressure metamorphism during the Alpine orogeny, e.g. as proposed by Rubatto et al. (2011) for the Sesia Nappe. A lower-pressure stage in between might have been associated with brittle fracturing of high-pressure phases like garnet, glaucophane, and omphacite while the second generations of these minerals might indicate a new stage of increasing pressures and/or temperatures. References Beltrando, M., Rubatto, D. & Manatschal, G. (2010): From passive margins to orogens: The link between ocean-continent transition zones and (ultra)high-pressure metamorphism. Geology, 6, 559-562. Dal Piaz, G.V., Cortiana, G., Del Moro, A., Martin, S., Pennacchioni, G. & Tartarotti, P. (2001): Tertiary age and paleostructural inferences of the eclogitic imprint in the Austroalpine outliers and Zermatt-Saas ophiolite, western Alps. Int. J. Earth Sci., 90, 668-684. Rubatto, D., Regis, D., Hermann, J., Boston, K., Engi, M., Beltrando, M. & McAlpine, S.R.B. (2011): Yo-yo subduction recorded by accessory minerals in the Italian Western Alps. Nature Geoscience, 4, 338-342.

A new species of Limnephilidae (Insecta: Trichoptera) from the Western Alps (Insecta: Trichoptera)

PubMed Central

GRAF, WOLFRAM; VITECEK, SIMON

2016-01-01

A new species of the alpine caddisfly genus Consorophylax (Trichoptera, Limnephilidae, Stenophylacini) and the female of the recently described C. vinconi Graf & Malicky 2015 are described. The new species C. lepontiorum sp. nov. is a microendemic of the South-Western Alps and differs from its congeners in the shape of the superior and inferior appendages and the unique setation of the aedeagus, absent in all other Consorophylax species. The female of C. vinconi is characterized by the unique formation of the anal tube. Potential effects of alpine orogenesis, phenology and climatic oscillation on speciation of aquatic insects inhabiting high-altitude habitats are discussed. The description of C. lepontiorum sp. nov. accentuates the significance of the Western Alps as harbours of aquatic insect biodiversity, and demonstrates the necessity of faunal and taxonomic studies in Europe – a supposedly well-explored region. PMID:27069351

Paleomagnetic and AMS study of Permian and Triassic rocks from the Hronic Nappe and Paleogene rocks from the Central Carpathian Paleogene Basin, Western Carpathians

NASA Astrophysics Data System (ADS)

Márton, Emö; Madzin, Jozef; Bučová, Jana; Grabowski, Jacek; Plašienka, Dušan; Aubrecht, Roman

2017-04-01

The Hronic (Choč) units form the highest cover nappe system of the Central Western Carpathians which was emplaced over the Fatric (Krížna) nappe system during the Late Cretaceous. The Permian (red beds and lava flows) and Triassic (sediments) rocks, the main targets of our study, were affected only by diagenetic or very low-grade, burial-related recrystallization and were tilted and transported together. The pre-late Cretaceous sequence is overlapped by Paleogene mainly flysch sequences. Three laboratories (Bratislava, Budapest and Warsaw) were involved in standard paleomagnetic processing and AMS measurements of the samples, while Curie-points were determined in Budapest. The site/locality mean paleomagnetic directions obtained were significantly different from the local direction of the present Earth magnetic field, indicating the long term stability of the paleomagnetic signal. The magnetic fabrics varied from un-oriented to dominantly schistose with well-defined lineations. The latter were normally subhorizontal, although subvertical maxima also occurred among the Triassic sediments. Shallow inclinations, after tilt corrections, suggest near-equatorial position for most of the Permian and Lower Triassic, while around 20°N for the Middle-Upper Triassic localities. The paleomagnetic declinations are interpreted in terms of CW tectonic rotations, which are normally larger for the Permian than for the Triassic samples, although there are some differences within the same age groups. This may be attributed to differential movements during nappe emplacement or subsequent tectonic disturbances. For two localities from the Paleogene cover sequence of the Hronic units, close to the main sampling area (Low Tatra Mts) of the present study documented fairly large CCW rotations, thus obtained additional evidence for the general CCW rotation of the Central Western Carpathians during the Cenozoic. Thus, we conclude that the Cenozoic CCW rotation was pre-dated by large CW

PHENOALP: a new project on phenology in the Western Alps

NASA Astrophysics Data System (ADS)

Cremonese, E.

2009-04-01

PHENOALP is a new EU co-funded Interreg Project under the operational programme for cross-border cooperation "Italy-France (Alps-ALCOTRA)" 2007 - 2013, aiming to get a better understanding of phenological changes in the Alps. The major goals of the project are: 1- The implementation of an observation network in the involved territories (i.e. the Aosta Valley and the Savoies in the Western Alps); 2- The definition of a common observation strategy and common protocols; 3- The involvement of local community members (e.g. through schools) in the observation activities as a way to increase the awareness on the issue of the effects of climate change. Project leader is the Environmental Protection Agency of Aosta Valley (ARPA Valle d'Aosta - IT) and the partners are the Research Center on High Altitude Ecosystem (CREA - FR), Mont Avic Regional Parc (IT), Bauges Massif Regional Natural Parc (FR) and the Protected Area Service of Aosta Valley (IT). Project activities are: 1. Pheno-plantes: definition of common observation protocols (e.g. field observation and webcams) of different alpine species (trees and herbaceous) and implementation of the observation network; analysis of the relations between climate and phenological events; application and evaluation of phenological models. 2. Pheno-detection: remote sensing of European larch and high elevation pastures with MODIS data; multitemporal analysis (2000-2011) of phenological variations in the Western Alps. 3. Pheno-flux: analysis of the relation between the seasonal and interannual variability of plant phenology and productivity, assessed measuring CO2 fluxes (eddy-covariance technique), radiometric indexes and phenological events at specific (European larch stand and alpine pastures) monitoring site. 4. Pheno-zoo: definition of common observation protocols for the phenology of animal taxa (birds, mammals, amphibians and insects) along altitudinal gradients; implementation of the observation network. 5. Inter

The Western Tauern Window (Eastern Alps): Timing and Interplay of Folds and Sinistral Shear Zones as Result of South-Alpine Indentation

NASA Astrophysics Data System (ADS)

Schneider, Susanne; Rosenberg, Claudio; Hammerschmidt, Konrad

2010-05-01

The Tauern Window (TW) is the only domain within the Eastern Alps where deep crustal, Tertiary metamorphic rocks were exhumed to surface. The window is bounded by large-scale faults, partly considered to be responsible for its exhumation (e.g., Selverstone 1988, Fügenschuh 1997), and it is also cross cut internally by large-scale shear zones, whose significance in terms of type and timing of deformation, exhumation, and large-scale kinematic links is the subject of our investigation. These shear zones (Ahorn, Olperer, Greiner, Ahrntal) are widespread throughout the western TW, from the mm- to the km-scale. They are sinistral and located in the steep limbs of upright antiforms, forming a mylonitic foliation, that strikes parallel to the axial planes of these upright folds. We present new structural and geochronological data, obtained by in-situ dating of microstructurally defined syn- and postkinematic grains, to constrain the duration and termination of folding and sinistral shearing. Previous dating suggested initiation of shearing contemporaneous to nappe stacking between 32-and 30Ma, ongoing until 15Ma (Glodny et al., 2008). However, the fabric of the dated grains was not related to deformation phases defined from structural overprinting relationships, and the classical separation technique did not allow to separate synkinematic from pre- and post- kinematic grains. The northern margin of the western TW is pervasively overprinted by the Ahorn Shear Zone (Rosenberg & Schneider 2008), which shows S-side up kinematic indicators in addition to the sinistral ones, and a pronounced southward increase in metamorphic grade from lower greenschist facies to amphibolite facies conditions, within 2km. Phengites of the mylonitic foliation dated with the Rb/Sr in-situ technique, yield formation ages of 14-24Ma . The southern margin of the western TW is overprinted by the sinistral Ahrntal Fault (Schneider et al. 2009), which cuts discordantly several nappes from the

Palaeomagnetic time and space constraints of the Early Cretaceous Rhenodanubian Flysch zone (Eastern Alps)

NASA Astrophysics Data System (ADS)

Dallanave, Edoardo; Kirscher, Uwe; Hauck, Jürgen; Hesse, Reinhard; Bachtadse, Valerian; Wortmann, Ulrich Georg

2018-06-01

The Rhenodanubian Flysch zone (RDF) is a Lower Cretaceous-lower Palaeocene turbidite succession extending for ˜500 km from the Danube at Vienna to the Rhine Valley (Eastern Alps). It consists of calcareous and siliciclastic turbidite systems deposited in a trench abyssal plain. The age of deposition has been estimated through micropalaeontologic dating. However, palaeomagnetic studies constraining the age and the palaeolatitude of deposition of the RDF are still missing. Here, we present palaeomagnetic data from the Early Cretaceous Tristel and Rehbreingraben Formations of the RDF from two localities in the Bavarian Alps (Rehbrein Creek and Lainbach Valley, southern Germany), and from the stratigraphic equivalent of the Falknis Nappe (Liechtenstein). The quality of the palaeomagnetic signal has been assessed by either fold test (FT) or reversal test (RT). Sediments from the Falknis Nappe are characterized by a pervasive syntectonic magnetic overprint as tested by negative FT, and are thus excluded from the study. The sediments of the Rehbreingraben Formation at Rehbrein Creek, with positive RT, straddle magnetic polarity Chron M0r and the younger M΄-1r΄ reverse event, with an age of ˜127-123 Ma (late Barremian-early Aptian). At Lainbach Valley, no polarity reversals have been observed, but a positive FT gives confidence on the reliability of the data. The primary palaeomagnetic directions, after correction for inclination shallowing, allow to precisely constrain the depositional palaeolatitude of the Tristel and Rehbreingraben Formations around ˜28°N. In a palaeogeographic reconstruction of the Alpine Tethys at the Barremian/Aptian boundary, the RDF is located on the western margin of the Briançonnais terrain, which was separated from the European continent by the narrow Valais Ocean.

Magnetic fabric study of rock deformation during alpine tectonic evolution on a cross section through the Eastern Alps (Austria)

NASA Astrophysics Data System (ADS)

Gruber, K.; Scholger, R.; Pueyo, E. L.

2010-05-01

Measurements of anisotropy of magnetic susceptibility (AMS) were carried out on samples from more than seventy sites collected in the Eastern Alps. The sites were taken alongside a North-South transect (about 15°30` East Longitude) from Scheibbs in the North to Kapfenberg in the South, comprising most of the Northern Calcareous Alps (NCA) nappes, Helvetic and Penninic Flysh units as well as the greywacke zone. Samples were taken in detail mostly in Mesozoic rocks of the NCA, from North to South: Bajuvaric (Frankenfels, Lunz, Sulzbach and Reisalpen nappes), Tirolic (Ötscher, Göller, Rotwald-Gindelstein nappes) and Juvavic (Mürzalpen nappe) system. Two to six sites per thrust sheet or nappe were analysed for a structural investigation of the relationship between magnetic fabric and tectonic strain. Standard paleomagnetic drill cores were taken. All measurements were performed in the Petrophysics and Paleomagnetic laboratories of the University of Leoben using AGICO MFK1-Kappabridge susceptibility system and a 2-G cryogenic magnetometer. Statistical evaluation of the AMS data was perfomed using the software package AGICO ANISOFT 4.2. (Chadima et al., 2009). Throughout the Eastern Alps transect distinct changes of the magnetic fabric are observed. Primary sedimentary fabrics and very low susceptibility values are dominant in most cases in the northernmost and southernmost part of the transect. Some inverse fabrics were found in few sites of the nappes and the percentage increases towards the south which might be related to tectonic events. Contrastingly, isotropic fabrics dominate in the middle part. The Helvetic and Penninic Flysh units yield in general weak oblate fabrics. A few sites show a tendency to inverse fabrics which indicate the presence of a certain amount of strain within this unit. The oblate fabrics of the Helvetic and Flysh units show either shallow NE dipping or slightly steeper SW dipping k1-axis orientation. Within the inverse fabrics, even

Phenology in the Western Alps: first results of the PhenoALP project

NASA Astrophysics Data System (ADS)

Cremonese, Edoardo; Tracol, Yann

2010-05-01

along altitudinal transects of artificial nest-boxes. Moreover a protocol for the monitoring of the reproductive phases of Rana temporaria has been defined and observations are done in some ponds along an elevation gradient. A third activity of the project aims to analyse the relations between the seasonal and interannual variability of plant phenology and productivity, assessed measuring CO2 fluxes. To achieve this goal, two eddy covariance towers have been installed in a larch forest (2150 m asl) and in an alpine grassland (2160 m asl) in sites where phenology is monitored by field observations and webcams. Associated with these activities, a great effort is made towards the involvement of educational institutions in the observations of the seasonal changes of alpine ecosystems. During 2010, five school complexes located in the Italian side of the Western Alps will be involved in the French monitoring network of phenology in the Alps: Phenoclim (http://www.crea.hautesavoie.net/eng/phenoclim/index.php).Italian project partners will train schools to start phenological observations.

Recent progress in recognition of UHP metamorphism in allochthons of the Scandinavian Caledonides (Seve Nappe Complex and Tromsø Nappe)

NASA Astrophysics Data System (ADS)

Janák, Marian; Ravna, Erling; Majka, Jarosław; Klonowska, Iwona; Kullerud, Kåre; Gee, David; Froitzheim, Nikolaus

2017-04-01

During the last ten years, UHP rocks have been discovered within far-travelled allochthons of the Scandinavian Caledonides including the Seve Nappe Complex (SNC) of the Middle Allochthon and Tromsø Nappe within the Uppermost Allochthon. The first evidence for UHP conditions in the SNC was documented in a kyanite-bearing eclogite dike within the Friningen garnet peridotite. Subsequently, UHP conditions were determined for phengite eclogite and garnet pyroxenite from Stor Jougdan and pelitic gneisses from Åreskutan. Finally, diamond was found in metasedimentary rocks of the SNC at three localities (Snasahögarna, Åreskutan and most recently near Saxnäs), c. 250 km apart, confirming regional UHP conditions within this allochthon. In the Tromsø Nappe (northern Norway), evidence for UHP metamorphism comes from phengite- and kyanite-bearing eclogites from Tønsvika and Tromsdalstind, and diamond-bearing gneisses from Tønsvika. Microdiamond occurs in-situ as single and composite (mostly with Mg-Fe carbonate) inclusions within garnet and zircon. The calculated P-T conditions for the diamond-bearing samples are 4.1-4.2 GPa/830-840°C (Åreskutan), and 3.5-4.0 GPa/ 750-800°C (Tønsvika), in the diamond stability field. The UHP metamorphism in the SNC and Tromsø Nappe is probably Late Ordovician (c. 460-450 Ma), i.e. c. 40-50 Ma older than that in the Western Gneiss Region of southwestern Norway. Whereas the latter occurred during the collision between Laurentia and Baltica in the Late Silurian to Early Devonian, the processes leading to Ordovician UHP metamorphism occurred during closure of the Iapetus Ocean and are less well understood. The occurrence of two UHP metamorphic events in the Scandinavian Caledonides implies subduction, exhumation, and re-subduction of continental crust. This is an observation that could be of importance for the understanding of orogeny at convergent plate boundaries in general. The following questions remain to be answered: (1) Was UHP

Mantle wedge anisotropy beneath the Western Alps: insights from Receiver Function analysis

NASA Astrophysics Data System (ADS)

Piana Agostinetti, Nicola; Salimbeni, Simone; Pondrelli, Silvia; Malusa', Marco; Zhao, Liang; Eva, Elena; Solarino, Stefano; Paul, Anne; Guillot, Stéphane; Schwartz, Stéphane; Dumont, Thierry; Aubert, Coralie; Wang, Qingchen; Zhu, Rixiang

2017-04-01

Orogens and subductions zones are the locus where crustal materials are recycled into the upper mantle. Such rocks undergo to several metamorphic reactions during which their seismic properties vary due to the changes in P-T conditions. Metamorphic reactions can imply: (a) the formation of schist-like materials, and (b) a pronounced water flux from the subducted crust. Both these processes should generate highly anisotropic volumes at upper mantle depths. Thus, unveiling the presence of seismic anisotropy at such depth level can put constraints on the metamorphic reactions and the P-T conditions of the subducted materials. The Alpine orogen is composed of three main regions where different geodynamic processes shaped a highly heterogeneous mountain chain. Beneath the Alps, a high velocity body has been imaged sinking in the upper mantle, indicating the presence of a relict of subduction. Such subduction process has been probably terminated with the closure of the Piemont-Liguria Ocean, but evidence of continental subduction has been found beneath the Western Alps. Seismic anisotropy is likely to develop both in the subducted materials and in the mantle wedge, where serpentinized materials could be found due to the low T conditions. We analysed P receiver function (RF) from 46 seismic stations deployed along a linear array crossing the Western Alps, where previous studies revealed the presence of the subducted European lower crust to 80 km depth. RF is a widely used tool for reconstructing subsurface seismic structures, based on the recognition of P-to-S converted phases in teleseismic P-wave coda. The RF data-set is migrated at depth and decomposed into azimuthal harmonics. Computing the first, k=0, and the second, k=1, harmonics allows to separate the "isotropic" contribution, due to the change of the isotropic properties of the sampled materials (recorded on the k=0 harmonics), from the "anisotropic" contribution, where the energy is related to the propagation of

Provenance analysis of the Voirons Flysch (Gurnigel nappe, Haute-Savoie, France): stratigraphic and palaeogeographic implications

NASA Astrophysics Data System (ADS)

Ragusa, Jérémy; Kindler, Pascal; Segvic, Branimir; Ospina-Ostios, Lina Maria

2017-04-01

The Chablais Prealps (Haute-Savoie, France) represent a well-preserved accretionary wedge of the Western Alpine Tethys. They comprise a stack of sedimentary nappes related to palaeogeographic realms ranging from the Ultrahelvetic to the Southern Penninic. The provenance analysis is based on the Gazzi-Dickinson method and on QEMSCAN® for heavy-minerals. The Quartzose petrofacies is the most important of the two sources, and supplied three of the four formations of the Voirons Flysch. It is similar to the sources that fed the other flyschs from the Gurnigel nappe. It is characterised by a mature, quartz-rich assemblage and a heavy-mineral population dominated by apatite and the zircon-tourmaline-rutile mineral group. These observations suggest a Clastic wedge provenance. The Feldspathic petrofacies is derived from a feldspar-rich source associated with metamorphic clasts and a heavy-mineral population dominated by garnet. This provenance characterises only one formation of the Voirons Flysch, and is related to the axial belt provenance. This provenance analysis shows that the Middle Eocene to Early Oligocene Voirons Flysch was fed by two sources, in contrast to the other flyschs of the Gurnigel nappe, and further suggests that this flysch was not deposited in the Piemont Ocean but in the Valais domain. Based on the results and comparative provenance analysis with the other flyschs of the Gurnigel nappe, we propose a generic feeding model which involves the Sesia-Dent Blanche nappe, the sedimentary nappes incorporated in the accretionary prism, and probably the Briançonnais basement.

Shear wave velocities in the upper mantle of the Western Alps: new constraints using array analysis of seismic surface waves

NASA Astrophysics Data System (ADS)

Lyu, Chao; Pedersen, Helle A.; Paul, Anne; Zhao, Liang; Solarino, Stefano

2017-07-01

It remains challenging to obtain absolute shear wave velocities of heterogeneities of small lateral extension in the uppermost mantle. This study presents a cross-section of Vs across the strongly heterogeneous 3-D structure of the western European Alps, based on array analysis of data from 92 broad-band seismic stations from the CIFALPS experiment and from permanent networks in France and Italy. Half of the stations were located along a dense sublinear array. Using a combination of these stations and off-profile stations, fundamental-mode Rayleigh wave dispersion curves were calculated using a combined frequency-time beamforming approach. We calculated dispersion curves for seven arrays of approximately 100 km aperture and 14 arrays of approximately 50 km aperture, the latter with the aim of obtaining a 2-D vertical cross-section of Vs beneath the western Alps. The dispersion curves were inverted for Vs(z), with crustal interfaces imposed from a previous receiver function study. The array approach proved feasible, as Vs(z) from independent arrays vary smoothly across the profile length. Results from the seven large arrays show that the shear velocity of the upper mantle beneath the European plate is overall low compared to AK135 with the lowest velocities in the internal part of the western Alps, and higher velocities east of the Alps beneath the Po plain. The 2-D Vs model is coherent with (i) a ∼100 km thick eastward-dipping European lithosphere west of the Alps, (ii) very high velocities beneath the Po plain, coherent with the presence of the Alpine (European) slab and (iii) a narrow low-velocity anomaly beneath the core of the western Alps (from the Briançonnais to the Dora Maira massif), and approximately colocated with a similar anomaly observed in a recent teleseismic P-wave tomography. This intriguing anomaly is also supported by traveltime variations of subvertically propagating body waves from two teleseismic events that are approximately located on

The initial superposition of oceanic and continental units in the southern Western Alps: constraints on geometrical restoration and kinematics of the continental subduction wedge

NASA Astrophysics Data System (ADS)

Dumont, Thierry; Schwartz, Stéphane; Matthews, Steve; Malusa, Marco; Jouvent, Marine

2017-04-01

The tectonic contact separating continental and oceanic units is preserved at outcrop in many locations within the Western Alps. The contact has experienced prolonged and progressive deformation during Oligocene collision and subsequent 'extrusive' contraction which is approximately westerly-directed (Dumont et al., 2012). Despite variable metamorphic grade, this tectonic contact displays a relative consistency of tectonostratigraphic and structural characteristics. Removal of the Oligocene and younger deformation is a critical requirement to allow assessment of the kinematic evolution during the Eocene continental subduction phase. The best preserved relationships are observed near the base of the Helminthoid Flysch nappes, in the footwall of the Penninic thrust, or in the external part of the Briançonnais zone. Here, the oceanic units are composed of detached Cretaceous sediments, but they are underlain locally by an olistostrome containing basaltic clasts. Further to the east, the internal boundary of the Briançonnais zone s.l. (including the 'Prepiedmont units'), is frequently marked by breccia or megabreccia, but is strongly affected by blueschist-facies metamorphism and by approximately easterly directed backfolding and backthrusting. At one locality, there is compelling evidence that the oceanic and continental units were already tectonically stacked and metamorphosed (together) 32Ma ago. Some megabreccias of mixed continental/oceanic provenance can be interpreted as a metamorphic equivalent of the external olistostrome, products of the initial pulses of tectonic stacking. The overlying units are composed dominantly of metasediments, containing distributed ophiolitic megaboudins (Tricart & Schwartz, 2006). Further east again, the tectonic contact separates the Dora-Maira continental basement from the Mt. Viso units which are predominantly composed of oceanic lithosphere. Both the Dora-Maira and Mt. Viso units are eclogitic, but the HP peak is apparently

What controls the reactivation or preservation of distal ocean-continent transitions: the example of the Err-Platta nappes, SE Switzerland

NASA Astrophysics Data System (ADS)

Epin, Marie-Eva; Manatschal, Gianreto; Amann, Méderic

2016-04-01

Studies in the Alps suggest that remnants of former Ocean-Continent Transitions (OCT) can be preserved, even in internal parts of mountain belts. In the past, these units have been erroneously interpreted as either mélanges related to subduction channels or polyphase penetrative Alpine deformation. Good examples have been described from the eclogitic Piemonte units in the Western Alps and in Corsica [Beltrando et al., 2014], leading to the question of what may have controlled the preservation of these structures. In our study we used the example of the Err-Platta nappes that expose remnants of the OCT of the former Alpine Tethys. The aim of our presentation is to: 1) define the characteristic features of an OCT across a fossil magma-poor rifted margin, and 2) show the control of the rift-inherited structures during the subsequent reactivation of the OCT. The characteristics of OCTs at magma-poor rifted margins are the juxtaposition of serpentinized mantle and crustal rocks and pre-rift sediments limited by brittle extensional detachment faults sealed by syn- and post-tectonic sediments locally associated with magmatic rocks. Thus, in contrast to proximal margins, where lithologies are continuous layer cakes, OCTs are characterized by non-continuous layers and isolated blocks. To identify extensional detachment faults in mountain belts, different fingerprints can be found such as fault rocks (gouges and cataclasites) that bear a mantle derived fluid signature, or the occurrence of massive breccias that contain clasts of the underlying exhumed basement. Using field examples, we will show how Alpine structures selectively reactivated some inherited structures of the OCT, while others remained undeformed and were preserved in the nappe stack. How far the complex morphology, fault architecture and rheology of OCTs control the reactivation is still unclear, however, it appears that serpentinization fronts, or former extensional detachment faults may have played a key

A detrital garnet fingerprint of the Central Swiss Alps

NASA Astrophysics Data System (ADS)

Stutenbecker, Laura; Berger, Alfons; Schlunegger, Fritz

2017-04-01

Detrital garnet is a promising candidate to reliably fingerprint sediment sources in the Alps, which has so far been complicated by the wide range and similarity of some of the lithologies. Garnet is present in most Alpine sediments, is easy to identify, is fairly stable and, most importantly, reflects the type and the metamorphic grade of its source rock in its chemical composition. This study aims to establish fingerprints based on detrital garnet composition for the most important tectonic units of the Central Alps, including European, Penninic and Adriatic basement rocks and their respective meta-sedimentary cover. Sediments collected from modern rivers, which drain representative portions of the individual tectonic units, contain a natural mixture of the various garnet populations present in each unit. We selected six catchments in southwestern Switzerland draining the External Massifs, Helvetic sediments and the Penninic nappe stack at the transition of Alpine greenschist- to amphibolite-facies metamorphism in order to test the variability of Alpine garnets and the role of inherited (pre-Alpine) garnets. Extraordinary grossular- and spessartine-rich garnets of the External massifs, which experienced greenschist facies metamorphism, are clearly distinguishable from generally almandine-rich garnets supplied by the higher-grade metamorphic Penninic nappe stack. The variable pyrope-, grossular- and spessartine-components of these almandine-rich garnets can be used to further distinguish pre-Alpine, Alpine eclogite-facies and low-grade metasedimentary garnets. This fingerprint has the potential to be used for reconstructing sediment sources, transport and dispersal patterns in a variety of settings throughout the Alpine sedimentary record.

Adriatic indentation of the Eastern Alps - nature vs. analogue models

NASA Astrophysics Data System (ADS)

Favaro, S.; Scharf, A.; Schuster, R.; Handy, M. R.

2013-12-01

The Eastern Alps underwent late Oligocene-Miocene indentation by the Adriatic microplate, followed by rapid Miocene exhumation in the Tauern Window and orogen-parallel escape. Analogue models of indentation in the Eastern Alps indicate that exhumation of orogenic crust in front of the Adriatic indenter was coeval, with faults and post-nappe folds forming an asymmetrical conjugate pattern in front of the indenting block (Ratschbacher et al 1991, Rosenberg et al 2007). The amount and rate of exhumation is greatest at this location, but decrease laterally towards an unconfined boundary of the models that represents the retreating Carpathian subduction orogen. In nature, however, isotopic age patterns of deeply buried and exhumed basements rocks in the Tauern Window of the Eastern Alps indicate that cooling and possibly also exhumation were diachronous along strike of the orogen. In the westernmost Tauern Window, previous thermal modeling of fission-track ages (Fügenschuh et al 1997) revealed that rapid exhumation (≥ 1mm/a) lasted from 20-13 Ma and appears to have been triggered by sinistral transpression along the Guidicarie Belt beginning in Late Oligocene time. Rapid cooling (≥25°C/Ma) from 550 to 270°C lasted from 18-12 Ma (von Blanckenburg et al 1989; Fügenschuh et al 1997). In the easternmost part, however, rapid cooling from a similar peak temperature lasted from 23-20 Ma and ended no later than 17 Ma. Thus, rapid exhumation cannot have begun later than 23-21 Ma. Cooling patterns in the eastern central part of the Tauern Window are more complex and reflect the combined effects of doming and extensional exhumation. New Rb-Sr mica ages in post-nappe basement domes generally decrease from NW (muscovite: 26 Ma; biotite: 22 Ma) to SE (muscovite: 22 Ma; biotite: 18 Ma). We interpret these trends to show that doming began in the south-central part of the Tauern Window and then migrated to the SE while the entire basement nappe pile underwent orogen

Lithospheric architecture of the South-Western Alps revealed by multiparameter teleseismic full-waveform inversion

NASA Astrophysics Data System (ADS)

Beller, S.; Monteiller, V.; Operto, S.; Nolet, G.; Paul, A.; Zhao, L.

2018-02-01

The Western Alps, although being intensively investigated, remains elusive when it comes to determining its lithospheric structure. New inferences on the latter are important for the understanding of processes and mechanisms of orogeny needed to unravel the dynamic evolution of the Alps. This situation led to the deployment of the CIFALPS temporary experiment, conducted to address the lack of seismological data amenable to high-resolution seismic imaging of the crust and the upper mantle. We perform a 3-D isotropic full-waveform inversion (FWI) of nine teleseismic events recorded by the CIFALPS experiment to infer 3-D models of both density and P- and S-wave velocities of the Alpine lithosphere. Here, by FWI is meant the inversion of the full seismograms including phase and amplitude effects within a time window following the first arrival up to a frequency of 0.2 Hz. We show that the application of the FWI at the lithospheric scale is able to generate images of the lithosphere with unprecedented resolution and can furnish a reliable density model of the upper lithosphere. In the shallowest part of the crust, we retrieve the shape of the fast/dense Ivrea body anomaly and detect the low velocities of the Po and SE France sedimentary basins. The geometry of the Ivrea body as revealed by our density model is consistent with the Bouguer anomaly. A sharp Moho transition is followed from the external part (30 km depth) to the internal part of the Alps (70-80 km depth), giving clear evidence of a continental subduction event during the formation of the Alpine Belt. A low-velocity zone in the lower lithosphere of the S-wave velocity model supports the hypothesis of a slab detachment in the western part of the Alps that is followed by asthenospheric upwelling. The application of FWI to teleseismic data helps to fill the gap of resolution between traditional imaging techniques, and enables integrated interpretations of both upper and lower lithospheric structures.

Dung beetle (Coleoptera: Scarabaeoidea) assemblages in the western Italian Alps: benchmark data for land use monitoring.

PubMed

Tocco, Claudia; Villet, Martin H

2016-01-01

Traditional agro-pastoral practices are in decline over much of the Alps (MacDonald et al. 2000), leading to shrub and tree encroachment, and this represents one of the main threats for the conservation of alpine biodiversity, as many plant and animal species are dependent on the presence of semi-natural open habitats. However, quantifying this environmental change and assessing its impact on biodiversity may be difficult, especially in the context of sparse historical survey data. The accessibility of contemporary data about local biodiversity surveys in general, and indicator taxa in particular, is an essential consideration for planning future evaluations of conservation status in the Alps and for conservation plans that use ecological indicators to monitor temporal changes in biodiversity. Dung beetles are important ecosystem service providers (Nichols et al. 2008) that have been assessed as a good ecological indicator taxon in several studies (reviewed by Nichols and Gardner 2011), and although the Alps is perhaps one of the best-studied regions in respect of dung beetles, there are still only eight readily-accessible publications. We have augmented and comprehensively reviewed the data from these publications. We first provide data about changes on a temporal scale of seasons in a dung beetle community in the western Italian Alps, an issue that has to be addressed in the local assemblages because it would affect regional biomonitoring and conservation research. This survey of 12 099 individuals belonging to 22 species illustrates a distinct seasonal pattern at a single site. Second, we collate the results of 13 published surveys of the presence of 46 species of dung beetles in 11 valleys in the western Italian Alps in the period from 2005 to 2012, a period of accelerated change in land use that started around 1945 (MacDonald et al. 2000). Because ten of the surveys used baited pitfall traps and four more used manual collection of specimens, the abundance data

A magnetotelluric feasibility study of the Alps

NASA Astrophysics Data System (ADS)

Ritter, O.; Weckmann, U.

2016-12-01

The Alps are a famous and extensive mountain range system in central Europe. The mountains were formed as the African and Eurasian tectonic plates collided and they have been a prime target for geological and geophysical investigations since the beginning of modern geosciences. Consequently, the Alps have been investigated with active and passive seismological methods and extensive sets of potential field data exist. Hardly anything is known, however, about the deep electrical conductivity structure, as it has been notoriously difficult to acquire magnetotelluric (MT) data in the Alps. The Alps are densely populated and a lot of infrastructure for tourism has been built over the years. MT measurements, which rely on natural variations of the electromagnetic background fields, are severely hampered by this man-made noise. Here, we report on a feasibility study to acquire MT data in the Alps, where all stations are deployed outside the valleys, on high mountain ranges and alpine pastures. Overall we recorded MT data at 7 stations, along an approximately north-south profile centred on Mayrhofen in the Austrian Alps. The average station spacing was 5 kilometers. The data were processed using robust remote-reference processing and the results clearly show that MT measurements are feasible. We used Mare2DEM for 2D inversion to include a somewhat realistic topography. The 2D section indicates moderate resistivity for the top 2 - 5 km, consistent with the regional geology, which suggests (meta-) sedimentary sequences. From depths of 5 km and below resistivities exceed 5,000 Ohmm. This means we can sense very deep with MT but also, that we should be cautious with an interpretation of this short profile. The data also clearly indicate 3D effects. We therefore propose to deploy an array of stations covering the entire Alps in USArray style, e.g. with a station spacing of approximately 50 km, to derive a 3D model of the deep electrical resistivity structure of the Alps. Such a

P wave anisotropic tomography of the Alps

NASA Astrophysics Data System (ADS)

Hua, Yuanyuan; Zhao, Dapeng; Xu, Yixian

2017-06-01

The first tomographic images of P wave azimuthal and radial anisotropies in the crust and upper mantle beneath the Alps are determined by joint inversions of arrival time data of local earthquakes and teleseismic events. Our results show the south dipping European plate with a high-velocity (high-V) anomaly beneath the western central Alps and the north dipping Adriatic plate with a high-V anomaly beneath the Eastern Alps, indicating that the subduction polarity changes along the strike of the Alps. The P wave azimuthal anisotropy is characterized by mountain chain-parallel fast-velocity directions (FVDs) in the western central Alps and NE-SW FVDs in the Eastern Alps, which may be caused by mantle flow induced by the slab subductions. Our results reveal a negative radial anisotropy (i.e., Vph < Vpv) within the subducting slabs and a positive radial anisotropy (i.e., Vph > Vpv) in the low-velocity mantle wedge, which may reflect the subvertical plate subduction and its induced mantle flow. The results of anisotropic tomography provide important new information on the complex mantle structure and dynamics of the Alps and adjacent regions.

Detrital zircon age patterns from turbidites of the Balagne and Piedmont nappes of Alpine Corsica (France): Evidence for an European margin source

NASA Astrophysics Data System (ADS)

Lin, Wei; Rossi, Philippe; Faure, Michel; Li, Xian-Hua; Ji, Wenbin; Chu, Yang

2018-01-01

At the front of metamorphic Cenozoic Alpine nappe of Schistes Lustrés, Western Alpine Corsica (France) exposes non- to very low grade metamorphic nappes, such as the Piedmont nappes, Upper nappes, and the Balagne nappe. The provenance of the Balagne nappe remains still opened: an origin close to the Corsican continental margin; or an origin far East from the Corsican margin toward the "Apenninic" oceanic domain. This would constrain that the Balagne ophiolite be derived from the opposite OCT (Ocean - Continent transition), close to a microcontinent located to the East of the Mesozoic Corsican margin. A systematic U-Pb dating of 586 detrital zircon grains collected from the turbidites in the Balagne and Piedmont nappes has been performed to constrain the source of sediments. The zircon grains yield U-Pb age spectra ranging from Neoarchean to Late Paleozoic with age peaks at 2600 Ma, 2080 Ma, 1830 Ma, 910 Ma, 600 Ma, 560 Ma, 450 Ma, 330 Ma and 280 Ma with different continental model ages (TDM2) from 3.5 Ga to 1.0 Ga. The variety of composition of the Corsican batholith, unique in its present Mediterranean environment, and in spite of Alpine transcurrent movements, provide a key to analyze the detrital zircon age distribution patterns of sedimentary rocks. These new results i) confirm the lack of any Cretaceous zircon that validates absence of a magmatic arc of this age, at least in the surroundings of the turbiditic formations from the Balagne and the Piedmont nappes; ii) fully support an European provenance of detritus of the Balagne nappe, iii) put forward evidence that no ophiolitic zircon was contained neither in the Cretaceous nor in the Eocene turbidites samples, and iv) question both the deposition of the Piedmont Narbinco flysch within the ocean continent transition and its possible relationships with the Late Cretaceous Pyrenean basins.

Ice cap melting and low-viscosity crustal root explain the narrow geodetic uplift of the Western Alps

NASA Astrophysics Data System (ADS)

Chéry, J.; Genti, M.; Vernant, P.

2016-04-01

More than 10 years of geodetic measurements demonstrate an uplift rate of 1-3 mm/yr of the high topography region of the Western Alps. By contrast, no significant horizontal motion has been detected. Two uplift mechanisms have been proposed: (1) the isostatic response to denudation responsible for only a fraction of the observed uplift and (2) the rebound induced by the Wurmian ice cap melting which predicts a broader uplifting region than the one evidenced by geodetic observations. Using a numerical model to fit the geodetic data, we show that a crustal viscosity contrast between the foreland and the central part of the Alps, the latter being weaker with a viscosity of 1021 Pa s, is needed. The vertical rates are enhanced if the strong uppermost mantle beneath the Moho is interrupted across the Alps, therefore allowing a weak vertical rheological anomaly over the entire lithosphere.

Dung beetle (Coleoptera: Scarabaeoidea) assemblages in the western Italian Alps: benchmark data for land use monitoring

PubMed Central

Villet, Martin H

2016-01-01

Abstract Background Traditional agro-pastoral practices are in decline over much of the Alps (MacDonald et al. 2000), leading to shrub and tree encroachment, and this represents one of the main threats for the conservation of alpine biodiversity, as many plant and animal species are dependent on the presence of semi-natural open habitats. However, quantifying this environmental change and assessing its impact on biodiversity may be difficult, especially in the context of sparse historical survey data. The accessibility of contemporary data about local biodiversity surveys in general, and indicator taxa in particular, is an essential consideration for planning future evaluations of conservation status in the Alps and for conservation plans that use ecological indicators to monitor temporal changes in biodiversity. Dung beetles are important ecosystem service providers (Nichols et al. 2008) that have been assessed as a good ecological indicator taxon in several studies (reviewed by Nichols and Gardner 2011), and although the Alps is perhaps one of the best-studied regions in respect of dung beetles, there are still only eight readily-accessible publications. We have augmented and comprehensively reviewed the data from these publications. New information We first provide data about changes on a temporal scale of seasons in a dung beetle community in the western Italian Alps, an issue that has to be addressed in the local assemblages because it would affect regional biomonitoring and conservation research. This survey of 12 099 individuals belonging to 22 species illustrates a distinct seasonal pattern at a single site. Second, we collate the results of 13 published surveys of the presence of 46 species of dung beetles in 11 valleys in the western Italian Alps in the period from 2005 to 2012, a period of accelerated change in land use that started around 1945 (MacDonald et al. 2000). Because ten of the surveys used baited pitfall traps and four more used manual

Tectono-thermal evolution in a region with thin-skinned tectonics: the western nappes in the Cantabrian Zone (Variscan belt of NW Spain)

NASA Astrophysics Data System (ADS)

Bastida, F.; Brime, C.; García-López, S.; Sarmiento, G. N.

The palaeotemperature distribution in the transition from diagenesis to metamorphism in the western nappes of the Cantabrian Zone (Somiedo, La Sobia and Aramo Units) are analysed by conodont colour alteration index (CAI) and illite crystallinity (IC). Structural and stratigraphic control in distribution of CAI and IC values is observed. Both CAI and IC value distributions show that anchizonal conditions are reached in the lower part of the Somiedo Unit. A disruption of the thermal trend by basal thrusts is evidenced by CAI and IC values. There is an apparent discrepancy between the IC and CAI values in Carboniferous rocks of the Aramo Unit; the IC has mainly anchizonal values, whereas the CAI has diagenetic values. Discrepant IC values are explained as a feature inherited from the source area. In the Carboniferous rocks of the La Sobia Unit, both IC and CAI indicate diagenetic conditions. The anchimetamorphism predated completion of emplacement of the major nappes; it probably developed previously and/or during the early stages of motion of the units. Temperature probably decreased when the metamorphosed zones of the sheets rose along ramps and were intensely eroded. In the context of the Iberian Variscan belt, influence of tectonic factors on the metamorphism is greater in the internal parts, where the strain and cleavage are always present, than in the external parts (Cantabrian Zone), where brittle deformation and rock translation are dominant, with an increasing role of the burial on the metamorphism.

The Haselgebirge evaporitic mélange in central Northern Calcareous Alps (Austria): Part of the Permian to Lower Triassic rift of the Meliata ocean?

PubMed

Schorn, Anja; Neubauer, Franz; Genser, Johann; Bernroider, Manfred

2013-01-11

For the reconstruction of Alpine tectonics of the Eastern Alps, the evaporitic Permian to Lower Triassic Haselgebirge Formation plays a key role in (1) the origin of Haselgebirge bearing nappes, (2) the inclusion of magmatic and metamorphic rocks revealing tectonic processes not preserved in other units, and (3) the debated mode of emplacement of the nappes, namely gravity-driven or tectonic. Within the Moosegg quarry of the central Northern Calcareous Alps gypsum/anhydrite bodies are tectonically mixed with lenses of sedimentary rocks and decimeter- to meter-sized tectonic clasts of plutonic and subvolcanic rocks and rare metamorphics. We examined various types of (1) widespread biotite-diorite, meta-syenite, (2) meta-dolerite and rare ultramafic rocks (serpentinite, pyroxenite) as well as (3) rare metamorphic banded meta-psammitic schists and meta-doleritic blueschists. The apparent 40 Ar/ 39 Ar biotite ages from three biotite-diorite, meta-dolerite and meta-doleritic blueschist samples with variable composition and fabrics range from 248 to 270 Ma (e.g., 251.2 ± 1.1 Ma) indicating a Permian age of cooling after magma crystallisation or metamorphism. The chemical composition of biotite-diorite and meta-syenite indicates an alkaline trend interpreted to represent a rift-related magmatic suite. These, as well as Permian to Jurassic sedimentary rocks, were incorporated during Cretaceous nappe emplacement forming the sulphatic Haselgebirge mélange. The scattered 40 Ar/ 39 Ar white mica ages of a meta-doleritic blueschist (of N-MORB origin) and banded meta-psammitic schist are ca. 349 and 378 Ma, respectively, proving the Variscan age of pressure-dominated metamorphism. These ages are similar to detrital white mica ages reported from the underlying Rossfeld Formations, indicating a close source-sink relationship. According to our new data, the Haselgebirge bearing nappe was transported over the Lower Cretaceous Rossfeld Formations, which include many clasts

Kinematics of syn- and post-exhumational shear zones at Lago di Cignana (Western Alps, Italy): constraints on the exhumation of Zermatt-Saas (ultra)high-pressure rocks and deformation along the Combin Fault and Dent Blanche Basal Thrust

NASA Astrophysics Data System (ADS)

Kirst, Frederik; Leiss, Bernd

2017-01-01

Kinematic analyses of shear zones at Lago di Cignana in the Italian Western Alps were used to constrain the structural evolution of units from the Piemont-Ligurian oceanic realm (Zermatt-Saas and Combin zones) and the Adriatic continental margin (Dent Blanche nappe) during Palaeogene syn- and post-exhumational deformation. Exhumation of Zermatt-Saas (U)HP rocks to approximately lower crustal levels at ca. 39 Ma occurred during normal-sense top-(S)E shearing under epidote-amphibolite-facies conditions. Juxtaposition with the overlying Combin zone along the Combin Fault at mid-crustal levels occurred during greenschist-facies normal-sense top-SE shearing at ca. 38 Ma. The scarcity of top-SE kinematic indicators in the hanging wall of the Combin Fault probably resulted from strain localization along the uppermost Zermatt-Saas zone and obliteration by subsequent deformation. A phase of dominant pure shear deformation around 35 Ma affected units in the direct footwall and hanging wall of the Combin Fault. It is interpreted to reflect NW-SE crustal elongation during updoming of the nappe stack as a result of underthrusting of European continental margin units and the onset of continental collision. This phase was partly accompanied and followed by ductile bulk top-NW shearing, especially at higher structural levels, which transitioned into semi-ductile to brittle normal-sense top-NW deformation due to Vanzone phase folding from ca. 32 Ma onwards. Our structural observations suggest that syn-exhumational deformation is partly preserved within units and shear zones exposed at Lago di Cignana but also that the Combin Fault and Dent Blanche Basal Thrust experienced significant post-exhumational deformation reworking and overprinting earlier structures.

Geomorphological response of a landscape to long-term tectonic and glacial processes: the upper Rhône basin, Central Swiss Alps

NASA Astrophysics Data System (ADS)

Stutenbecker, Laura; Schlunegger, Fritz

2015-04-01

The Rhône River in the Central Swiss Alps drains a 5380 km2 large basin that shows a high spatial variability of bedrock lithology, exhumation rate, glacial conditioning and climate. All of these factors were recently discussed to control erosion rates in orogenic settings in general, and particularly in the Alps (e.g. Wittmann et al. 2007, Vernon et al. 2008, Norton et al. 2010a). Thanks to various and densely distributed data, the upper Rhône basin located between the Aar massif and Lake Geneva is a suitable natural laboratory to analyze the landscape's geomorphological state and controlling factors at a basin-scale. In this study, we extract geomorphological parameters along the channels of ca. 50 tributary basins of various sizes that contribute to the sediment budget of the Rhône River either through sediment supply by torrents or debris flows. Their catchments are located in either granitic basement rocks (External Massifs), oceanic meta-sedimentary and ophiolitic rocks (Penninic nappes) or fine-grained continental-margin sediments (Helvetic nappes). The analysis of longitudinal river profiles from DEMs and slope/area relationships show that all tributary rivers within the Rhône basin are in topographic transient state that is expressed by mainly convex or concave-convex channel shapes with several knickpoints of either tectonic-lithological or glacial origin. Furthermore, the frequency distribution of elevations (hypsometry) along the river channel allows identifying glacially inherited morphologies and the recent erosional front. The combination of those different geomorphological data yields to a categorization of the tributary rivers into three endmember groups: (1) streams with highly convex profiles, testifying to a strong glacial inheritance, (2) concave-convex channels with several knickzones and inherited morphologies of past glaciations, (3) predominantly concave, relatively steep rivers with minor knickpoints and inner gorges. Assuming that

Alternatives for the source of the exotic green clasts from Moldavian Nappes (East Carpathians, Romania)

NASA Astrophysics Data System (ADS)

Tatu, M.

2009-04-01

Important segment of the Carpathian chain, the East Carpathians consists of several tectonic units build up during the Mesozoic and Cenozoic closure of the Tethyan Ocean. These tectonic units are composed by crystalline basements and sedimentary covers, or only by sedimentary piles and they represent a result of two compressional phases of Alpine orogenesis: one during Late Cretaceous that was responsible for thrusting of Central East Carpathian Nappes and Outher Dacian Nappes, and a second phase during Early and Middle Miocene interval that involved the Moldavian Nappes as the external nappes (Sandulescu, 1988). The Moldavian Nappes consist of cover nappes tectonically detached from the basement upon which it was deposited. From inside towards outside several units occur: Convolute Flysch Nappe, Macla Nappe, Audia Nappe, Tarcau Nappe, Marginal Folds Nappe and Subcarpathian Nappe (Sãndulescu et al., 1981). If the internal units (up to Audia Nappe) are represented by the Cretaceous sediment piles, in the external units, especially in the Tarcau Nappe and also in the Marginal Folds Nappe the lithology is dominated by the Paleogene deposits, especially by the Oligocene formations. The most particular for these units are the presence of heterogeneous composition induced by the wildflysch type sedimentation. Previous researchers have considered the piles of the both units as flyschoid deposits, and for a minor central part (Slon Facies) they accepted a wildflysch scenario. Based on our field studies between Prahova valley (Romania) and Tisa upper stream basin (Ukraine), the different sedimentary strata (the Oligocene Tarcau, Fusaru, Kliwa sandstones, dysodilic and menilitic rocks, polymictic conglomerates, marls and argillaceous deposits together with Upper Cretaceous polymictic conglomerates and green-reddish argillaceous deposits) are tectonically mixed during the late-Oligocene - Middle Miocene events. The mechanism of sedimentary mélange is supposed to be related

Ice cap melting and low viscosity crustal root explain narrow geodetic uplift of the Western Alps

NASA Astrophysics Data System (ADS)

Chery, Jean; Genti, Manon; Vernant, Philippe

2016-04-01

More than 10 years of geodetic measurements demonstrate an uplift rate of 1-3 mm/yr of the high topography region of the Western Alps. By contrast, no significant horizontal motion has been detected. Three uplift mechanisms have been proposed so far: (1) the isostatic response to denudation. However this process is responsible for only a fraction of the observed uplift and (2) the rebound induced by the Wurmian ice cap melting. This process leads to a broader uplifting region than the one evidenced by geodetic observations. (3) a deep source motion associated with slab motion or some deep isostatic unbalance. Using a numerical model accounting for crustal and mantle rheology of the Alps and its foreland, we model the response to Wurmian ice cap melting. We show that a crustal viscosity contrast between the foreland and the central part of the Alps, the later being weaker with a viscosity of 1021 Pa.s, is needed to produce a narrow uplift. The vertical rates are enhanced if the strong uppermost mantle beneath the Moho is interrupted across the Alps, therefore allowing a weak vertical rheological anomaly thanks to the continuity between the low viscosity parts of the crust and mantle. References: Champagnac, J.-D., F. Schlunegger, K. Norton, F. von Blanckenburg, L. M. Abbühl, and M. Schwab (2009), Erosion-driven uplift of the modern Central Alps, Tectonophysics, 474(1-2), 236-249. Vernant, P., F. Hivert, J. Chéry, P. Steer, R. Cattin, and A. Rigo (2013), Erosion-induced isostatic rebound triggers extension in low convergent mountain ranges, geology, 41(4), 467-470.

Ethnobotanical and phytomedical knowledge in the North-Western Ligurian Alps.

PubMed

Cornara, Laura; La Rocca, Arianna; Terrizzano, Luca; Dente, Fulvio; Mariotti, Mauro Giorgio

2014-08-08

The ethnobotany of European alpine regions is much diversified and scarcely investigated. These regions retain a well-developed heritage culture and botanical traditional knowledge, favored by the isolated montane location. We carried out a study of therapeutic and traditional uses of native plants of a poorly explored area of the Western Italian Alps in the Ligurian region (NW Italy). The area has been the object of human activities since prehistoric ages, and an obliged crossroad for people moving across Provence, Liguria and Piemonte. The investigation was conducted in the upper Tanarello and Arroscia Valleys by using semi-structured, open interviews. Data were summarized by different indices--Relative Frequency of Citation (RFC), Cultural Value Index (CV), Ethnobotanicity Index (EI) and Informant Consensus Factor (Fic). A group of 65 informants were interviewed, yielding an inventory of 199 botanical taxa from 64 families, and a total of 2661 citations. A total of 13 categories of use were found, of which the most frequent ones were medicinal and food. In addition, 12 main medicinal subcategories were recorded. Botanicals were mainly used to treat digestive system, respiratory system, and the skin. A relevant role was played by plants with digestive and remineralizing properties. On the basis of quantitative analysis (RFC and CV indices) among the 30 most relevant plants are included rare and/or protected species, such as Achillea ligustica, Arnica montana, Gentiana ligustica, Gentiana lutea, and Achillea erba-rotta. An exhaustive prospect of the ethnobotanical knowledge in North-Western Ligurian Alps has been achieved through the recording of a large number of data. About 50% of the recorded uses have survived in the area. A great traditional importance is retained by species such as Artemisia absinthium, Lavandula angustifolia and Arnica montana which were formerly cultivated and marketed for their therapeutic virtues. A substantial role is also attributable

New Zealand Southern Alps

NASA Image and Video Library

2001-06-20

This anaglyph from the MISR instrument aboard NASA Terra spacecraft shows the rugged Southern Alps extending some 650 kilometers along the western side of New Zealand South Island. 3D glasses are necessary to view this image.

The potential of detrital garnet as a provenance proxy in the Central Swiss Alps

NASA Astrophysics Data System (ADS)

Stutenbecker, Laura; Berger, Alfons; Schlunegger, Fritz

2017-04-01

Detrital garnet is a promising candidate to reliably fingerprint sediment sources in the Alps, which has so far been complicated by the wide range and similarity of some of the lithologies. Garnet is present in most Alpine sediments, is easy to identify, is fairly stable and, most importantly, reflects the type and the metamorphic grade of its source rock in its chemical composition. This study aims to establish fingerprints based on detrital garnet composition for the most important tectonic units of the Central Alps, including European, Penninic and Adriatic basement rocks and their respective metasedimentary covers. Sediments collected from modern rivers, which drain representative portions of the individual tectonic units, contain a natural mixture of the various garnet populations present in each unit. We selected six catchments in southwestern Switzerland draining the External massifs, Helvetic sediments and the Penninic nappe stack at the transition of Alpine greenschist- to amphibolite-facies metamorphism in order to test the variability of Alpine garnets and the role of inherited (pre-Alpine) garnets. Extraordinary grossular- and spessartine-rich garnets of the External massifs, which experienced greenschist facies metamorphism, are clearly distinguishable from generally almandine-rich garnets supplied by the higher-grade metamorphic Penninic nappe stack. The variable pyrope, grossular and spessartine components of these almandine-rich garnets can be used to further distinguish pre-Alpine, Alpine eclogite-facies and low-grade metasedimentary garnets. This provenance proxy has the potential to be used for reconstructing sediment sources, transport and dispersal patterns in a variety of settings throughout the Alpine sedimentary record.

Seismic signature of the Alpine indentation, evidence from the Eastern Alps

PubMed Central

Bianchi, I.; Bokelmann, G.

2014-01-01

The type of collision between the European and the Adriatic plates in the easternmost Alps is one of the most interesting questions regarding the Alpine evolution. Tectonic processes such as compression, escape and uplift are interconnected and shape this area. We can understand these ongoing processes better, if we look for signs of the deformation within the Earth's deep crust of the region. By collecting records from permanent and temporary seismic networks, we assemble a receiver function dataset, and analyze it with the aim of giving new insights on the structure of the lower crust and of the shallow portion of the upper mantle, which are inaccessible to direct observation. Imaging is accomplished by performing common conversion depth stacks along three profiles that crosscut the Eastern Alpine orogen, and allow isolating features consistently persistent in the area. The study shows a moderately flat Moho underlying a seismically anisotropic middle-lower crust from the Southern Alps to the Austroalpine nappes. The spatial progression of anisotropic axes reflects the orientation of the relative motion and of the stress field detected at the surface. These observations suggest that distributed deformation is due to the effect of the Alpine indentation. In the shallow upper mantle right below the Moho interface, a further anisotropic layer is recognized, extended from the Bohemian Massif to the Northern Calcareous Alps. PMID:26525181

Seismic signature of the Alpine indentation, evidence from the Eastern Alps.

PubMed

Bianchi, I; Bokelmann, G

2014-12-01

The type of collision between the European and the Adriatic plates in the easternmost Alps is one of the most interesting questions regarding the Alpine evolution. Tectonic processes such as compression, escape and uplift are interconnected and shape this area. We can understand these ongoing processes better, if we look for signs of the deformation within the Earth's deep crust of the region. By collecting records from permanent and temporary seismic networks, we assemble a receiver function dataset, and analyze it with the aim of giving new insights on the structure of the lower crust and of the shallow portion of the upper mantle, which are inaccessible to direct observation. Imaging is accomplished by performing common conversion depth stacks along three profiles that crosscut the Eastern Alpine orogen, and allow isolating features consistently persistent in the area. The study shows a moderately flat Moho underlying a seismically anisotropic middle-lower crust from the Southern Alps to the Austroalpine nappes. The spatial progression of anisotropic axes reflects the orientation of the relative motion and of the stress field detected at the surface. These observations suggest that distributed deformation is due to the effect of the Alpine indentation. In the shallow upper mantle right below the Moho interface, a further anisotropic layer is recognized, extended from the Bohemian Massif to the Northern Calcareous Alps.

Isolated, but transnational: the glocal nature of Waldensian ethnobotany, Western Alps, NW Italy.

PubMed

Bellia, Giada; Pieroni, Andrea

2015-05-07

An ethnobotanical field study on the traditional uses of wild plants for food as well as medicinal and veterinary plants was conducted in four Waldensian valleys (Chisone, Germanasca, Angrogna, and Pellice) in the Western Alps, Piedmont, NW Italy. Waldensians represent a religious Protestant Christian minority that originated in France and spread around 1,170 AD to the Italian side of Western Alps, where, although persecuted for centuries, approximately 20,000 believers still survive today, increasingly mixing with their Catholic neighbours. Interviews with a total of 47 elderly informants, belonging to both Waldensian and Catholic religious groups, were undertaken in ten Western Alpine villages, using standard ethnobotanical methods. The uses of 85 wild and semi-domesticated food folk taxa, 96 medicinal folk taxa, and 45 veterinary folk taxa were recorded. Comparison of the collected data within the two religious communities shows that Waldensians had, or have retained, a more extensive ethnobotanical knowledge, and that approximately only half of the wild food and medicinal plants are known and used by both communities. Moreover, this convergence is greater for the wild food plant domain. Comparison of the collected data with ethnobotanical surveys conducted at the end of the 19th Century and the 1980s in one of studied valleys (Germanasca) shows that the majority of the plants recorded in the present study are used in the same or similar ways as they were decades ago. Idiosyncratic plant uses among Waldensians included both archaic uses, such as the fern Botrychium lunaria for skin problems, as well as uses that may be the result of local adaptions of Central and Northern European customs, including Veronica allionii and V. officinalis as recreational teas and Cetraria islandica in infusions to treat coughs. The great resilience of plant knowledge among Waldensians may be the result of the long isolation and history of marginalisation that this group has faced

Interactions between geomorphology and vegetation in the Western Swiss Alps: first investigations

NASA Astrophysics Data System (ADS)

Giaccone, Elisa; Mariéthoz, Grégoire; Lambiel, Christophe

2017-04-01

The influence of earth surface processes can modify the microhabitat conditions and the species richness, composition and distribution patterns of plant communities. It is therefore important to understand how geomorphology affects the distribution of plant species to predict future vegetation evolution in a context of climate change. To better analyse the influence of geomorphology on vegetation growth in the alpine periglacial belt, we are studying various geomorphological processes (e.g. cryoturbation and solifluction), permafrost, nivation and ground surface characteristics at three focus sites of the Vaud Alps (Western Swiss Alps). The sites are located at an altitude range comprised between 2000 and 2600 m a.s.l. The geomorphology is characterized mainly by the presence of small glaciers, large moraine deposits, rock glaciers and debris slopes. Monitoring of the ground surface temperatures, permafrost mapping, vegetation survey and drone flights have been carried out to investigate in detail the environmental variables. Initial results show a heterogeneous vegetation cover depending on time since deglaciation, debris size, ground stability and soil age. Debris pioneer species are present on moraines, rock glaciers and debris slope; grassland are developed in zones not affected by LIA glacier advances or other interfering processes such as avalanches. The high-resolution images obtained from drone flights (5 cm/pixel) allow a detailed study of the granulometry. In order to use such geomorphological information on a wider area of interest, the local data acquired on focus sites have to be spatialized to a regional scale. This is accomplished by developing an approach based on remote sensing and multiple-point geostatistics that performs a semi-automated geomorphological mapping (SAGM). The SAGM is based on a training image composed by a geomorphological map yet existent, an orthophoto, the slope, the aspect, the curvature, the granulometry classification and

Permian A-type rhyolites of the Muráň Nappe, Inner Western Carpathians, Slovakia: in-situ zircon U-Pb SIMS ages and tectonic setting

NASA Astrophysics Data System (ADS)

Ondrejka, Martin; Li, Xian-Hua; Vojtko, Rastislav; Putis, Marian; Uher, Pavel; Sobocký, Tomas

2018-04-01

Three representative A-type rhyolitic rock samples from the Muráň Nappe of the inferred Silicic Unit of the Inner Western Carpathians (Slovakia) were dated using the high-precision SIMS U-Pb isotope technique on zircons. The geochronological data presented in this paper is the first in-situ isotopic dating of these volcanic rocks. Oscillatory zoned zircon crystals mostly revealed concordant Permian (Guadalupian) ages: 266.6 ± 2.4 Ma in Tisovec-Rejkovo (TIS-1), 263.3 ± 1.9 Ma in Telgárt-Gregová Hill (TEL-1) and 269.5 ± 1.8 Ma in Veľká Stožka-Dudlavka (SD-2) rhyolites. The results indicate that the formation of A-type rhyolites and their plutonic equivalents are connected to magmatic activity during the Permian extensional tectonics and most likely related to the Pangea supercontinent break-up.

From the Western Alps across Central Europe: Postglacial recolonisation of the tufa stream specialist Rhyacophila pubescens (Insecta, Trichoptera)

PubMed Central

2011-01-01

Background Dispersal rates, i.e. the effective number of dispersing individuals per unit time, are the product of dispersal capacity, i.e. a species physiological potential for dispersal, dispersal behaviour, i.e. the decision to leave a habitat patch in favour of another, and connectivity of occupied habitat. Thus, dispersal of species that are highly specialised to a certain habitat is limited by habitat availability. Species inhabiting very stable environments may also adopt a sedentary life-style. Both factors should lead to strong genetic differentiation in highly specialised species inhabiting stable environments. These two factors apply to our model species Rhyacophila pubescens a highly specialised freshwater insect that occurs in tufa springs, a very stable habitat. Results We examined the genetic population structure and phylogeography using range-wide mtCOI sequence and AFLP data from 333 individuals of R. pubescens. We inferred the location of Pleistocene refugia and postglacial colonisation routes of R. pubescens, and examined ongoing local differentiation. Our results indicate intraregional differentiation with a high number of locally endemic haplotypes, that we attributed to habitat specificity and low dispersal rates of R. pubescens. We observed high levels of genetic diversity south of the Alps and genetic impoverishment north of the Alps. Estimates of migrants placed the refugium and the source of the colonisation in the Dauphiné Alps (SW Alps). Conclusions This is the first example of an aquatic insect with a colonisation route along the western margin of the Alps to the Central European highlands. The study also shows that specialisation to a stable environment may have promoted a behavioural shift to decreased dispersal rates, leading to stronger local population differentiation than in less specialised aquatic insects. Alternatively, the occurrence of highly specialised tufa spring habitats may have been more widespread in the past, leading

Deciphering the driving forces of short-term erosion in glacially impacted landscapes, an example from the Western Alps

NASA Astrophysics Data System (ADS)

Glotzbach, Christoph; van der Beek, Peter; Carcaillet, Julien; Delunel, Romain

2013-04-01

Tectonic uplift is the main driver of long-term erosion, but climate changes can markedly affect the link between tectonics and erosion, causing transient variations in short-term erosion rate. Here we study the driving forces of short-term erosion rates in the French Western Alps as estimated from in-situ produced cosmogenic 10Be and detrital apatite fission-track thermochronology analysis of stream sediments. Short-term erosion rates from 10Be analyses vary between ~0.27 and ~1.33 mm/yr, similar to rates measured in adjacent areas of the Alps. Part of the data scales positively with elevation, while the full dataset shows a significant positive correlation with steepness index of streams and normalized geophysical relief. Mean long-term exhumation and short-term erosion rates are comparable in areas that are exhuming rapidly (>0.4 km/Myr), but short-term rates are on average two-three (and up to six) times higher than long-term rates in areas where the latter are slow (<0.4 km/Myr). These findings are supported by detrital apatite fission-track age distributions that appear to require similar variations in erosion rates. Major glaciations strongly impacted the external part of the Alps, increasing both long-term exhumation rates as well as relief (e.g. Glotzbach et al. 2011; Häuselmann et al. 2007; Valla et al.). Based on our data, it seems that glacial impact in the more slowly eroding internal part is mainly restricted to relief, which is reflected in high transient short-term erosion rates. The data further reveal that normalized steepness index and ridgeline geophysical relief are well correlated with (and could be used as proxies for) short-term erosion, in contrast to slope, corroborating studies in purely fluvial landscapes. Our study demonstrates that climate change, e.g. through occurrence of major glaciations, can markedly perturb landscapes short-term erosion patterns in regions of tectonically controlled long-term exhumation. Glotzbach C., P.A. van

Evidences for the austroalpine - southalpine up-doming after the end of the variscan orogenesis (central and eastern alps)

NASA Astrophysics Data System (ADS)

Martin, S.; Tumiati, S.

2003-04-01

The structural and petrographic studies of the basement units in the Alpine region, independently from their present tectonic setting in the nappe pile, suggest that at the end of the Variscan orogenesis they were in such a position that they suffered relevant up-doming and cooling since Late Carboniferous (Thöni, 1981; Mottana et al., 1985; Martin et al., 1996; Bertotti et al., 1999). This up-doming has been interpreted as due to an isostatic rebound related to the detachment of the slab after the cessation of the subduction at the end of the Variscan orogenesis (Neubauer and Handler, 2000; Ranalli, 2003). The metamorphic setting of the Southalpine basement between the Tonale pass and Lake Maggiore in the Southern Alps, is due to processes which, by extension denudation and erosion, locally took to the surface portions of middle-to-high grade basement, within a horst-graben environment (Cassinis et al., 1997). The basements of the Orobic, Lake Como and Lake Maggiore areas are composed of kyanite-garnet or sillimanite-bearing schists (e.g., Gneiss di Morbegno, Scisti di Edolo, Scisti dei Laghi; Boriani et al., 1990; Siletto et al., 1993), or of low grade schists (e.g., Filladi di Ambria) intruded by Early Permian plutons, covered by continental and volcanic deposits of Late Carboniferous to Permian age, after a marked unconformity (Cadel et al., 1996). The thickness of this clastic cover ranges between a few hundreds to thousands of meters; the clast compositions suggest a low-grade basement as a dominant source; the structures indicate alternance of uplift and collapse and continue deformation during sedimentation (Cassinis et al., 1974). Most of the Upper Austroalpine units of the central and eastern Alps (e.g., Tonale nappe, Languard, Ortles and Campo units) have structural and lithological similarities with the Orobic, Lake Como and Lake Maggiore basement units confirming their appartenance to the same pre-Alpine paleogeographic environment which suffered up

The emplacement of the Peridotite Nappe of New Caledonia and its bearing on the tectonics of obduction

NASA Astrophysics Data System (ADS)

Gautier, Pierre; Quesnel, Benoît; Boulvais, Philippe; Cathelineau, Michel

2016-12-01

The Peridotite Nappe of New Caledonia is one of the few ophiolites worldwide that escaped collisional orogeny after obduction. Here we describe the deformation associated with serpentinization in two klippes of the nappe in northwestern New Caledonia. The klippes are flat lying and involve S/SW vergent reverse-slip shear zones which are true compressional structures in origin. Further northeast, the nappe is folded in association with the development of a steep schistosity in low-grade metasediments. This difference in structural style indicates that the Peridotite Nappe experienced compression at greater depths toward its root zone, suggesting a "push from the rear" mechanism of emplacement. This supports the view that the nappe has been emplaced through horizontal contraction sustained by plate convergence. We establish a crustal-scale cross section at the end of the obduction event, before Neogene extension. This involves a large fold nappe of high-pressure rocks bounded from below by a major thrust. Furthermore, we show that obduction in New Caledonia occurred through dextral oblique convergence. Oblique convergence probably resulted from the initial obliquity between the subduction trench and the continental ribbon that became incorporated in it. This obliquity can solve the paradox of the Peridotite Nappe seemingly being emplaced at the same time the high-pressure rocks were exhumed. Oblique convergence together with focused erosional denudation on the northeastern flank of the island led to exhumation of the metamorphic rocks in a steep fold nappe rising through the rear part of the orogen.

Relationship of orogen-parallel exhumation in the Tauern and Rechnitz Windows to eastward lateral escape of the Eastern Alps

NASA Astrophysics Data System (ADS)

Favaro, Silvia; Schuster, Ralf; Scharf, Andrea; Handy, Mark R.

2013-04-01

Neogene orogen-parallel extensional in the Tauern and Rechnitz Windows and eastward lateral extrusion of the Eastern Alps are manifested, respectively, by exhumation and cooling and by subsidence of pull-apart basins. These events overlap in time, giving rise to the question of their relationship. The Tauern Window exposes relics of the European continental margin (Subpenninic units) and Alpine Tethys Ocean (Penninic units) beneath units derived from the Adriatic microplate (Austroalpine nappes). In the eastern part of the Tauern Window, the Subpenninic and Penninic nappes are deformed by two domes (Sonnblick and Hochalm domes) and the intervening tight Mallnitz synform. Reddy et al. (1996) proposed that the Sonnblick dome cooled first based on a trend of decreasing Rb-Sr and Ar-Ar white mica and biotite ages from the northwestern part of the Sonnblick Dome to the southeastern part of the Hochalm dome. When combined with this existing dataset, new Rb/Sr biotite ages point to simultaneous cooling of the domes to below the closure temperature of this isotopic system. Rb-Sr muscovite ages decrease from 26-30 Ma in the northwest to 20-25 Ma in the southeast. Rb-Sr biotite ages young in the same direction from 20-23 Ma to 16-19 Ma. The biotite ages do not vary in a transect of the Mallnitz synform and are therefore inferred to post-date this structure. Apatite fission track data follow this same NW to SE trend. A SE increase in intensity of mylinitic shearing along strike of the Mallnitz synform is interpreted to be a manifestation of stretch faulting related to normal faulting along the central part of the Katschberg Shear Zone system at the eastern end of the Tauern Window (Scharf et al., submitted). We attribute the SE decrease of the biotite cooling ages to an increased component of tectonic unroofing towards the eastern margin of the Tauern Window. Three new Rb-Sr biotite ages in the range of 16-26 Ma from the lowermost Austroalpine units (Wechsel and Semmering

Patterns of landscape form in the upper Rhône basin, Central Swiss Alps, predominantly show lithologic controls despite multiple glaciations and variations in rock uplift rates

NASA Astrophysics Data System (ADS)

Stutenbecker, L. A.; Costa, A.; Schlunegger, F.

2015-10-01

The development of topography is mainly dependent on the interplay of uplift and erosion, which are in term controlled by various factors including climate, glaciers, lithology, seismic activity and short-term variables such as anthropogenic impact. While most studies have focused on the role of tectonics and climate on the landscape form and underlying processes, less attention has been paid on exploring the controls of lithology on erosion. The Central European Alps are characterized by a large spatial variability in exposed lithologies and as such offer an ideal laboratory to investigate the lithological controls on erosion and landscape form. Here, we focus on the ca. 5400 km2-large upper Rhône basin situated in the Central Swiss Alps to explore how the lithological architecture of the bedrock conditions the Alpine landscape. To this extent, we extract geomorphological parameters along the channels of ca. 50 tributary basins, whose catchments are located in either granitic basement rocks (External massifs), oceanic meta-sedimentary and ophiolitic rocks (Penninic nappes) or fine-grained continental-margin sediments (Helvetic nappes). The analysis of longitudinal river profiles show that all tributary rivers within the Rhône basin are in topographic transient state as testified by mainly convex or concave-convex longitudinal stream channel profiles with several knickpoints of either tectonic or glacial origin. In addition, although the entire Rhône basin shows a strong glacial inheritance (and is still partly glaciated) and some of the highest uplift rates recently measured in the Alps, the river network has responded differently to those perturbations as revealed by the morphometric data. In particular, tributary basins in the Helvetic nappes are the most equilibrated (concave river profiles, overall lower elevations, less steep slope gradients and lowest hypsometric integrals), while the tributaries located in the External massifs are least equilibrated

Eclogitic metatrondhjemites from metaophiolites of the Western Alps

NASA Astrophysics Data System (ADS)

Martin, Silvana; Tartarotti, Paola; Meyzen, Chrstine; Benciolini, Luca; Toffolo, Luca

2016-04-01

Eclogitic metatrondhjemites from metaophiolites of the Western Alps Martin S.**, Tartarotti P.*, Meyzen C. **, Benciolini L.***, Toffolo L. ** *Dipartimento di Scienze della Terra, Università degli Studi di Milano ** Dipartimento di Geoscienze, Università di Padova *** Dipartimento di Chimica, Fisica e Ambiente, Università di Udine In the Urtier valley (southern Aosta Valley, Italy), the Piemonte metaophiolites mainly consist of serpentinized peridotites including pods and boudinaged layers of Fe-metagabbro and trondhjemite transposed in the main eclogitic foliation. The contact between serpentinized peridotites and Fe-metagabbro/trondhjemite is locally lined by chloriteschist and rodingite. The high pressure parageneses in the Fe-metagabbro are omphacite-garnet-rutile-glaucophane-phengite, and in the metatrondhjemite plagioclase-quartz-phengite-clinozoisite-epidote-garnet, respectively. Bulk-rock major and trace elements in addition to O isotope analyses were performed in both rock types. Fe-metagabbros are characterized by MgO wt% ranging between 6.11 and 9.63%, ∑REE= 20-101 ppm, (La/Yb)N = 0.22-0.91; trondhjemites have SiO2 43%, Al2O3 ranging between 21 and 24%, CaO ranging between 17 and 20%, ∑REE = 172 - 272 ppm, (La/Yb)N ranging between 7.78 and 13.70. The δ18O is 5.9 ‰ in a Fe-metagabbro sample and 7.4 ‰ in a trondhjemite sample, suggesting that these rocks have been affected by a weak oceanic low temperature alteration. The high CaO content may indicate a metasomatic process which could have occurred during the oceanic stage or at high pressure conditions.

Modes of orogen-parallel stretching and extensional exhumation in response to microplate indentation and roll-back subduction (Tauern Window, Eastern Alps)

NASA Astrophysics Data System (ADS)

Scharf, A.; Handy, M. R.; Favaro, S.; Schmid, S. M.; Bertrand, A.

2013-09-01

The Tauern Window exposes a Paleogene nappe stack consisting of highly metamorphosed oceanic (Alpine Tethys) and continental (distal European margin) thrust sheets. In the eastern part of this window, this nappe stack (Eastern Tauern Subdome, ETD) is bounded by a Neogene system of shear (the Katschberg Shear Zone System, KSZS) that accommodated orogen-parallel stretching, orogen-normal shortening, and exhumation with respect to the structurally overlying Austroalpine units (Adriatic margin). The KSZS comprises a ≤5-km-thick belt of retrograde mylonite, the central segment of which is a southeast-dipping, low-angle extensional shear zone with a brittle overprint (Katschberg Normal Fault, KNF). At the northern and southern ends of this central segment, the KSZS loses its brittle overprint and swings around both corners of the ETD to become subvertical, dextral, and sinistral strike-slip faults. The latter represent stretching faults whose displacements decrease westward to near zero. The kinematic continuity of top-east to top-southeast ductile shearing along the central, low-angle extensional part of the KSZS with strike-slip shearing along its steep ends, combined with maximum tectonic omission of nappes of the ETD in the footwall of the KNF, indicates that north-south shortening, orogen-parallel stretching, and normal faulting were coeval. Stratigraphic and radiometric ages constrain exhumation of the folded nappe complex in the footwall of the KSZS to have begun at 23-21 Ma, leading to rapid cooling between 21 and 16 Ma. This exhumation involved a combination of tectonic unroofing by extensional shearing, upright folding, and erosional denudation. The contribution of tectonic unroofing is greatest along the central segment of the KSZS and decreases westward to the central part of the Tauern Window. The KSZS formed in response to the indentation of wedge-shaped blocks of semi-rigid Austroalpine basement located in front of the South-Alpine indenter that was part

Age and Prematurity of the Alps Derived from Topography

NASA Astrophysics Data System (ADS)

Hergarten, S.; Wagner, T.; Stüwe, K.

2010-09-01

The European Alps are one of the best studied mountain ranges on Earth, but yet the age of their topography is almost unknown. Even their relative stage of evolution is unclear: Are the Alps still growing, in a steady state or already decaying, and is there a significant difference between Western and Eastern Alps? Using a new geomorphic parameter we analyze the topography of the Alps and provide one of the first quantitative constraints demonstrating that the range is still in its infancy: In contrast to several other mountain ranges, the Alps have still more than half of their evolution to a geomorphic steady state to go. Combining our results with sediment budget data from the surrounding basins we infer that the formation of the present topography began only 5-6 million years ago. Our results question the apparent consensus that the topographic evolution is distributed over much of the Miocene and might give new impulses to the reconstruction of paleoclimate in Central Europe.

Constraints on the depositional age and tectonometamorphic evolution of marbles from the Biharia Nappe System (Apuseni Mountains, Romania)

NASA Astrophysics Data System (ADS)

Reiser, Martin Kaspar; Schuster, Ralf; Tropper, Peter; Fügenschuh, Bernhard

2017-04-01

Basement rocks from the Biharia Nappe System in the Apuseni Mountains comprise several dolomite and calcite marble sequences or lenses which experienced deformation and metamorphic overprint during the Alpine orogeny. New Sr, O and C-isotope data in combination with considerations from the lithological sequences indicate Middle to Late Triassic deposition of calcite marbles from the Vulturese-Belioara Series (Biharia Nappe s.str.). Ductile deformation and large-scale folding of the siliciclastic and carbonatic lithologies is attributed to NW-directed nappe stacking during late Early Cretaceous times (D2). The studied marble sequences experienced a metamorphic overprint under lower greenschist- facies conditions (316-370 °C based on calcite - dolomite geothermometry) during this tectonic event. Other marble sequences from the Biharia Nappe System (i.e. Vidolm and Baia de Arieș nappes) show similarities in the stratigraphic sequence and their isotope signature, together with a comparable structural position close to nappe contact. However, the dataset is not concise enough to allow for a definitive attribution of a Mesozoic origin to other marble sequences than the Vulturese-Belioara Series.

The European Alps as an interrupter of the Earth's conductivity structures

NASA Astrophysics Data System (ADS)

Al-Halbouni, D.

2013-07-01

Joint interpretation of magnetotelluric and geomagnetic depth sounding results in the period range of 10-105 s in the Western European Alps offer new insights into the conductivity structure of the Earth's crust and mantle. This first large scale electromagnetic study in the Alps covers a cross-section from Germany to northern Italy and shows the importance of the alpine mountain chain as an interrupter of continuous conductors. Poor data quality due to the highly crystalline underground is overcome by Remote Reference and Robust Processing techniques and the combination of both electromagnetic methods. 3-D forward modeling reveals on the one hand interrupted dipping crustal conductors with maximum conductances of 4960 S and on the other hand a lithosphere thickening up to 208 km beneath the central Western Alps. Graphite networks arising from Palaeozoic sedimentary deposits are considered to be accountable for the occurrence of high conductivity and the distribution pattern of crustal conductors. The influence of huge sedimentary Molasse basins on the electromagnetic data is suggested to be minor compared with the influence of crustal conductors. Dipping direction (S-SE) and maximum angle (10.1°) of the northern crustal conductor reveal the main thrusting conditions beneath the Helvetic Alps whereas the existence of a crustal conductor in the Briançonnais supports theses about its belonging to the Iberian Peninsula. In conclusion the proposed model arisen from combined 3-D modeling of noise corrected electromagnetic data is able to explain the geophysical influence of various structural features in and around the Western European Alps and serves as a background for further upcoming studies.

The tectonometamorphic evolution of the Apuseni Mountains (Romania): Geodynamic constraints for the evolution of the Alps-Carpathians-Dinaride system of orogens

NASA Astrophysics Data System (ADS)

Reiser, Martin; Schuster, Ralf; Fügenschuh, Bernhard

2015-04-01

New structural, thermobarometric and geochronological data allow integrating kinematics, timing and intensity of tectonic phases into a geodynamic model of the Apuseni Mountain, which provides new constraints for the evolution of the Alps-Carpathians-Dinaride system of orogens. Strong differences in terms of deformation directions between Early and Late Cretaceous events provide new constraints on the regional geodynamic evolution during the Cretaceous. Geochronological and structural data evidence a Late Jurassic emplacement of the South Apuseni Ophiolites on top of the Biharia Nappe System (Dacia Mega-Unit), situated in an external position at the European margin. Following the emplacement of the ophiolites, three compressive deformation phases affected the Apuseni Mountains during Alpine orogeny: a) NE-directed in-sequence nappe stacking and regional metamorphic overprinting under amphibolite-facies conditions during the Early Cretaceous ("Austrian Phase"), b) NW-directed thrusting and folding, associated with greenschist-facies overprinting, during the early Late Cretaceous ("Turonian Phase") and c) E-W internal folding together with brittle thrusting during the latest Cretaceous ("Laramian Phase"). Major tectonic unroofing and exhumation at the transition from Early to Late Cretaceous times is documented through new Sm-Nd Grt, Ar-Ar Ms and Rb-Sr Bt ages from the study area and resulted in a complex thermal structure with strong lateral and vertical thermal gradients. Nappe stacking and medium-grade metamorphic overprinting during the Early Cretaceous exhibits striking parallels between the evolution of the Tisza-Dacia Mega-Units and the Austroalpine Nappes (ALCAPA Mega-Unit) and evidences a close connection. However, Late Cretaceous tectonic events in the study area exhibit strong similarities with the Dinarides. Thus, the Apuseni Mountains represent the "missing link" between the Early Cretaceous Meliata subduction (associated with obduction of ophiolites

Subduction or obduction of continental crust in the northern Norwegian Caledonides? An example from the Nordmannvik Nappe

NASA Astrophysics Data System (ADS)

Faber, Carly; Stünitz, Holger; Jeřábek, Petr; Gasser, Deta; Konopásek, Jiří; Kraus, Katrin

2017-04-01

The debate about how and why continental crust is subducted is ongoing (Ingalls et al., 2016). This work uses the tectonmetamorphic history of a the Nordmannvik nappe in the northern Scandinavian Caledonides to discuss mid- to lower-crustal processes involved in the subduction of continental crust during the Caledonian Orogeny. The Nordmannvik Nappe, together with the underlying Kåfjord and Vaddas nappes, constitutes the Reisa Nappe Complex (RNC). The RNC overlies continental rocks of the Kalak Nappe Complex (KNC), and a clear oceanic suture between Baltican basement, the KNC and the RNC is missing. The RNC consists mainly of paragneisses of mostly unknown depositional age. Rare fossils in the Vaddas Nappe indicate that it at least partly consists of Ordovician-Silurian (>460 Ma) metasediments (Binns and Gayer, 1980). Both the Nordmannvik and Vaddas Nappes were intruded by gabbroic melt around 439 Ma at 9 kbar (c. 30 km) (Getsinger et al., 2013). Therefore, the host and intrusive rocks were already buried to positions far deeper than oceanic crust prior to nappe stacking. Nordmannvik nappe rocks show at least two distinct metamorphic fabrics; 1) an early high-grade kyanite-present migmatitic fabric and 2) a pervasive mylonitic fabric. Based on microstructural observations and pseudosection modeling these two fabrics are estimated to have formed at 770-800 °C and 9.4-11 kbar and 580-630 °C and 8-9.8 kbar, respectively. The presence of sillimanite in garnet cores (confirmed by Raman spectra) and garnet core compositions also suggest that an earlier, less well constrained, history exists with metamorphism around 815 °C and 8.7 kbar, similar to that recognized in the KNC, where it is dated to be pre-Caledonian. The lack of ocean floor rocks between the Nordmannvik Nappe and the Baltica basement suggests that the Nordmannvik Nappe and nappe units below were fairly proximal to Baltica prior to the Caledonian Orogeny. Their position below the Lyngen Nappe (Iapetus

Collision in the Central Alps: 1. Thermal Modelling

NASA Astrophysics Data System (ADS)

Engi, M.; Roselle, G. T.; Brouwer, F. M.; Berger, A.

2003-04-01

Recent tectonic reconstructions for the Central Alps, based in part on seismic profiles across of the orogen, have produced fairly robust kinematic scenarios for the Tertiary evolution. We have used these to set up 2D finite element models [1] to simulate the thermal evolution at orogenic scales. Results are helpful to understand the metamorphic and geochronological record in the Central Alps. Several features recognized as crucial in collisional orogens have been incorporated in our models: Adaptive grids are used to accommodate tectonic mass flow; properties of a tectonic accretion channel (TAC), situated near the footwall of the upper (Apulian) plate, are incorporated (TAC: 5-10 km wide [2]); a mobile fragment (pit: 5-10 km thick, 25-50 km long) at the plate interface is allowed to first be subducted, then to be extruded along the subduction channel to mid-crustal levels during the nappe stacking phase, and finally to be exhumed by backthrusting and erosion; partial melting and its thermal effects are computed. The thermal evolution in crucial parts of the model orogen is depicted in P-T and T-t trajectories, and in time slices showing the evolution of metamorphic facies and degrees of late partial melting. Comparison of simulation results with the regional distribution of (Eocene) high pressure fragments in the Lepontine Alps and of their (Oligo/Miocene) Barrovian overprint indicate that (a) decompression is near-isothermal along a very imited part of the path only; (b) the highest temperatures attained following collision do not reach the observed ˜700^oC unless the TAC is fairly radiogenic (heat production ge˜2 μW/m^3) or there is substantial heat advected by asthenospheric melts migrating up the subduction channel; (c) moderate amounts of partial melting occurred within the the TAC during decompression, following the assembly (at mid-crustal levels) of various crustal and mantle fragments with very diverse P-T-t histories. [1] Roselle et al. (2002) Amer

Subduction / exhumation dynamics: Petrochronology in the Glacier-Rafray slice (Western Alps, Italy)

NASA Astrophysics Data System (ADS)

Burn, Marco; Lanari, Pierre; Engi, Martin

2014-05-01

Petrochronology is the combination of in situ age-dating, geothermobarometry and structural geology and aims to unravel Pressure-Temperature-deformation-time (P-T-ɛ-t) paths. To link P-T conditions to deformation stages is daily business for metamorphic petrologists, but recent micro-mapping techniques (XMapTools program) provide an additional tool to achieve this goal. Absolute age is often difficult to assess in metamorphic rocks, as it is challenging to link specific P-T conditions to most of the mineral chronometers. Allanite is a common accessory phase in high-P metamorphic rocks and is a potential target to determine Th(-U)/Pb ages. Allanite from a leucocratic gneiss of the Glacier-Rafray slice in the western Alps consists of several chemically different zones: one major zone can be linked to a first high-P phengite generation. To determine the age of this high-P growth zone we used La-ICP-MS in situ techniques, which allowed us to date an appropriate growth rim per grain. Even so particular care was required when evaluating the isotope signals laser ablation leads to the excavation of a volume, which potentially can be chemically and/or age-zoned. We have developed a new method to track changes in the plasma during the ablation. This method aims to identify discrete age zones. La-ICP-MS spectra have been modeled so as to reproduce the shape of the spectra measured. These results indicate that high-P allanite first grew in equilibrium with phengite at 84 ± 4 Ma, whereas a second growth event occurred at ~40 Ma. A final epidotic rim grew at greenschist facies conditions, but this stage could not be dated. These findings have implications for our interpretation of several units in the Western Alps: In the Sesia Zone (former Adriatic margin), the earliest high-P metamorphism occurred at 85 Ma (Regis et al., 2014), precisely as the first high-P peak we discovered in the Glacier-Rafray slice. Austroalpine klippen such as this are commonly seen as extensional

Geochronology of pervasive top-to-the-SE directed deformation in the Caledonian nappe stack, Jämtland, Sweden

NASA Astrophysics Data System (ADS)

Bender, Hagen; Glodny, Johannes; Ring, Uwe; Almqvist, Bjarne S. G.; Grasemann, Bernhard; Stephens, Michael B.

2017-04-01

The Caledonian orogen of Scandinavia is thought to be a Himalaya-style head-on collisional orogen. However, in contrast to the Himalayas, the Caledonides are characterized by various ultrahigh-pressure belts of different ages, which make them a unique orogen on Earth. The Seve Nappe Complex (SNC) in Jämtland (Sweden) holds the key to better understanding the multi-stage tectonometamorphic evolution of a well-studied ultrahigh-pressure belt in the central Scandinavian Caledonides. Leucogranites and migmatic gneisses record an ultrahigh-pressure event at 460 Ma (Brueckner and Van Roermund, 2007; Grimmer et al., 2015), followed by migmatization at 440 Ma (Ladenberger at al. 2014). How those high-grade metamorphic events relate to the nappe structure remains elusive. We use a combined structural and geochronological approach to show that amphibolite- and greenschist-facies foreland-directed, top-to-the-ESE shearing formed the nappe pile consisting of the Köli Nappe overlying the SNC, the various nappes of the SNC, and the underlying units. Furthermore, we present new Rb-Sr internal multi-mineral isochron ages from two east-west transects in central and northern Jämtland. Most isotopic ages, complemented by a dense network of kinematic field data, range between 431 and 427 Ma. These ages are interpreted to reflect the timing of amphibolite-facies top-to-the-ESE-directed nappe stacking. Blackwall formation, i.e., in-situ chemical interaction between ultramafic rocks and felsic gneiss, at the Seve-Köli boundary occurred at 423 Ma, an age interpreted to postdate nappe emplacement. Biotite in top-to-the-ESE greenschist-facies shear bands in the Middle Köli nappe formed at 416 Ma. These new geochronological data show that the nappe assembly postdates deep subduction and subsequent decompression melting. Top-to-the-foreland directed thrusting occurred at 430 Ma and continued for several million years, while amphibolite-facies shear criteria yield older ages than

Urbanization and depopulation in the Alps.

PubMed

Batzing, W; Perlik, M; Dekleva, M

1996-11-01

Demographic developments in the European Alpine region are analyzed over the period 1870-1990. The region is defined as including parts of Germany, France, Italy, Liechtenstein, Austria, Switzerland, and Slovenia. "Studies of growth, stagnation, decline, commune size, and altitude in almost 6,000 communes are presented on three colored maps.... It is apparent that two highly divergent processes are at work and, accordingly, statistical mean values reveal little of importance. Approximately one-half of Alpine Europe is undergoing general economic and demographic growth and has experienced significant increase in population since the end of the agricultural era. This development has taken place primarily in low-lying valleys and basins and in areas bordering the Alps that have good access to transport routes. Tourism is not as widespread as generally assumed and is usually characterized by a punctate pattern. Only in the western part of the Eastern Alps does tourism account for widespread population growth at higher altitudes; elsewhere the Alps have not been affected by modern development and the economy and population are declining, with some areas in danger of becoming completely abandoned. The results challenge the earlier concept of the Alps as a rural region, once populated by peasants, where tourism now plays a major role." (EXCERPT)

Structurally controlled 'teleconnection' of large-scale mass wasting (Eastern Alps)

NASA Astrophysics Data System (ADS)

Ostermann, Marc; Sanders, Diethard

2015-04-01

In the Brenner Pass area (Eastern Alps) , closely ahead of the most northward outlier ('nose') of the Southern-Alpine continental indenter, abundant deep-seated gravitational slope deformations and a cluster of five post-glacial rockslides are present. The indenter of roughly triangular shape formed during Neogene collision of the Southern-Alpine basement with the Eastern-Alpine nappe stack. Compression by the indenter activated a N-S striking, roughly W-E extensional fault northward of the nose of the indenter (Brenner-normal fault; BNF), and lengthened the Eastern-Alpine edifice along a set of major strike-slip faults. These fault zones display high seismicity, and are the preferred locus of catastrophic rapid slope failures (rockslides, rock avalanches) and deep-seated gravitational slope deformations. The seismotectonic stress field, earthquake activity, and structural data all indicate that the South-Alpine indenter still - or again - exerts compression; in consequence, the northward adjacent Eastern Alps are subject mainly to extension and strike-slip. For the rockslides in the Brenner Pass area, and for the deep-seated gravitational slope deformations, the fault zones combined with high seismic activity predispose massive slope failures. Structural data and earthquakes mainly record ~W-E extension within an Eastern Alpine basement block (Oetztal-Stubai basement complex) in the hangingwall of the BNF. In the Northern Calcareous Alps NW of the Oetztal-Stubai basement complex, dextral faults provide defacement scars for large rockfalls and rockslides. Towards the West, these dextral faults merge into a NNW-SSE striking sinistral fault zone that, in turn, displays high seismic activity and is the locus of another rockslide cluster (Fern Pass cluster; Prager et al., 2008). By its kinematics dictated by the South-Alpine indenter, the relatively rigid Oetztal-Stubai basement block relays faulting and associated mass-wasting over a N-S distance of more than 60

Kinematic evolution of Internal Getic nappes (Serbian Carpathians, eastern Serbia)

NASA Astrophysics Data System (ADS)

Krstekanic, Nemanja; Stojadinovic, Uros; Toljic, Marinko; Matenco, Liviu

2017-04-01

The tectonic evolution of the Carpatho - Balkanides Mountains is less understood in the critical segment of the Serbian Carpathians due to lack of available kinematic data. We have performed a field kinematic analysis combined with existing information from previous local and regional studies by focusing on the internal part of this orogenic segment, where the three highest most units of the nappe stack are exposed and separated by large offsets thrusts, i.e. the Supragetic, Upper Getic and Lower Getic. These units expose their metamorphic basement and Permo-Mesozoic cover penetrated by syn- and post-kinematic plutons and overlain or otherwise in structural contact with the Neogene fill of intramontane basins and the one of the Morava river corridor located in the prolongation of the much larger Pannonian basin. The kinematic analysis demonstrates seven superposed tectonic events of variable magnitudes and effects. Available superposition criteria and the correlation with the regional evolution demonstrate that four events are major tectonic episodes, while three others have a more limited influence or are local effects of strain partitioning and rotations. The first deformation event observed is the late Early Cretaceous cataclastic to brittle thrusting and shearing associated with the emplacement of the Supragetic nappe over the Getic unit. The observed paleostress NW-SE to SW-NE compressional directions were affected by the subsequent Cenozoic oroclinal bending of the Carpathians nappe stack. The first event was followed by Late Cretaceous E-W compression associated with significant strike-slip and transpression, the paleostress orientation being affected by the same subsequent rotations. The Paleogene - Early Miocene activation of the Cerna - Jiu and Timok faults system that cumulates an observed offset of 100 km is associated with large strikes-slip deformation with presently observed NNE-SSW oriented compressional directions in the study area. The formation

Noninvasive molecular tracking of colonizing wolf (Canis lupus) packs in the western Italian Alps.

PubMed

Lucchini, V; Fabbri, E; Marucco, F; Ricci, S; Boitani, L; Randi, E

2002-05-01

We used noninvasive methods to obtain genetic and demographic data on the wolf packs (Canis lupus), which are now recolonizing the Alps, a century after their eradication. DNA samples, extracted from presumed wolf scats collected in the western Italian Alps (Piemonte), were genotyped to determine species and sex by sequencing parts of the mitochondrial DNA (mtDNA) control-region and ZFX/ZFY genes. Individual genotypes were identified by multilocus microsatellite analyses using a multiple tubes polymerase chain reaction (PCR). The performance of the laboratory protocols was affected by the age of samples. The quality of excremental DNA extracts was higher in samples freshly collected on snow in winter than in samples that were older or collected during summer. Preliminary mtDNA screening of all samples allowed species identification and was a good predictor of further PCR performances. Wolf, and not prey, DNA targets were preferentially amplified. Allelic dropout occurred more frequently than false alleles, but the probability of false homozygote determinations was always < 0.001. A panel of six to nine microsatellites would allow identification of individual wolf genotypes, also whether related, with a probability of identity of < 0.015. Genealogical relationships among individuals could be determined reliably if the number of candidate parents was 6-8, and most of them had been sampled and correctly genotyped. Genetic data indicate that colonizing Alpine wolves originate exclusively from the Italian source population and retain a high proportion of its genetic diversity. Spatial and temporal locations of individual genotypes, and kinship analyses, suggest that two distinct packs of closely related wolves, plus some unrelated individuals, ranged in the study areas. This is in agreement with field observations.

Local Environmental Factors Drive Divergent Grassland Soil Bacterial Communities in the Western Swiss Alps

PubMed Central

Pinto-Figueroa, Eric; Buri, Aline; Spangenberg, Jorge E.; Adatte, Thierry; Guisan, Antoine; van der Meer, Jan Roelof

2016-01-01

ABSTRACT Mountain ecosystems are characterized by a diverse range of climatic and topographic conditions over short distances and are known to shelter a high biodiversity. Despite important progress, still little is known on bacterial diversity in mountain areas. Here, we investigated soil bacterial biogeography at more than 100 sampling sites randomly stratified across a 700-km2 area with 2,200-m elevation gradient in the western Swiss Alps. Bacterial grassland communities were highly diverse, with 12,741 total operational taxonomic units (OTUs) across 100 sites and an average of 2,918 OTUs per site. Bacterial community structure was correlated with local climatic, topographic, and soil physicochemical parameters with high statistical significance. We found pH (correlated with % CaO and % mineral carbon), hydrogen index (correlated with bulk gravimetric water content), and annual average number of frost days during the growing season to be among the groups of the most important environmental drivers of bacterial community structure. In contrast, bacterial community structure was only weakly stratified as a function of elevation. Contrasting patterns were discovered for individual bacterial taxa. Acidobacteria responded both positively and negatively to pH extremes. Various families within the Bacteroidetes responded to available phosphorus levels. Different verrucomicrobial groups responded to electrical conductivity, total organic carbon, water content, and mineral carbon contents. Alpine grassland bacterial communities are thus highly diverse, which is likely due to the large variety of different environmental conditions. These results shed new light on the biodiversity of mountain ecosystems, which were already identified as potentially fragile to anthropogenic influences and climate change. IMPORTANCE This article addresses the question of how microbial communities in alpine regions are dependent on local climatic and soil physicochemical variables. We benefit

Local Environmental Factors Drive Divergent Grassland Soil Bacterial Communities in the Western Swiss Alps.

PubMed

Yashiro, Erika; Pinto-Figueroa, Eric; Buri, Aline; Spangenberg, Jorge E; Adatte, Thierry; Niculita-Hirzel, Hélène; Guisan, Antoine; van der Meer, Jan Roelof

2016-11-01

Mountain ecosystems are characterized by a diverse range of climatic and topographic conditions over short distances and are known to shelter a high biodiversity. Despite important progress, still little is known on bacterial diversity in mountain areas. Here, we investigated soil bacterial biogeography at more than 100 sampling sites randomly stratified across a 700-km 2 area with 2,200-m elevation gradient in the western Swiss Alps. Bacterial grassland communities were highly diverse, with 12,741 total operational taxonomic units (OTUs) across 100 sites and an average of 2,918 OTUs per site. Bacterial community structure was correlated with local climatic, topographic, and soil physicochemical parameters with high statistical significance. We found pH (correlated with % CaO and % mineral carbon), hydrogen index (correlated with bulk gravimetric water content), and annual average number of frost days during the growing season to be among the groups of the most important environmental drivers of bacterial community structure. In contrast, bacterial community structure was only weakly stratified as a function of elevation. Contrasting patterns were discovered for individual bacterial taxa. Acidobacteria responded both positively and negatively to pH extremes. Various families within the Bacteroidetes responded to available phosphorus levels. Different verrucomicrobial groups responded to electrical conductivity, total organic carbon, water content, and mineral carbon contents. Alpine grassland bacterial communities are thus highly diverse, which is likely due to the large variety of different environmental conditions. These results shed new light on the biodiversity of mountain ecosystems, which were already identified as potentially fragile to anthropogenic influences and climate change. This article addresses the question of how microbial communities in alpine regions are dependent on local climatic and soil physicochemical variables. We benefit from a unique 700

Driving factors for torrential mass-movements occurrence in the Western Alps

NASA Astrophysics Data System (ADS)

Tiranti, Davide; Cremonini, Roberto; Asprea, Irene; Marco, Federica

2016-02-01

To understand the behaviour of torrential processes in the alpine environment, the conditions mainly responsiblefor the occurrence of these phenomena have to be identified and distinguished(classified) aspredisposing and triggering factors. In this regard, this study is aimed to understanding which factors lead to the occurrence of a given torrential processes in alpine catchments in the Western Alps, where information on past events are exhaustive and characterized by a long historical series. More than 769 documented torrential eventsoccurred from 1728 to 2015 within 78 catchments. Datasets concerning climate, geology and morphology, land use and the presence of historical landslide activity have been elaborated as input for multivariate statistical analysis to characterize the behaviour of the catchments. The results pinpoint the factors that mainly drive the type of torrential dominant process occurring in a given catchment, its occurrence probability, and its frequency. This study has demonstrated that catchments characterized by a significant percentage of outcropping rocks show a greater occurrence of torrential processes, especially hyperconcentrated flows and debris flows; on the contrary highly vegetated catchments are typically subject to water flows. This result can be a useful tool for the evaluation of hazards related to this specific phenomenon, making it possible to predict the most likely torrential processes that can be generated in a specific basin, given the characteristics of outcropping rock and vegetation cover.

The role of serpentinite melanges in the unroofing of UHPM rocks: An example from the Western Alps of Italy: Chapter 6

USGS Publications Warehouse

Blake, M. Clark; Moore, D.E.; Jayko, A.S.; Coleman, Robert G.

1995-01-01

The ultrahigh pressure metamorphic rocks (UHPM) of the Dora-Maira continental massif are overlain by a stack of oceanic nappes. Metamorphic grade appears to increase downward but with marked discontinuities between each of the nappes, suggesting that section has been removed along the bounding faults. This apparent omission of section is greatest in the lowest oceanic unit where a serpentinite melange containing blocks and slabs of eclogite, metamorphosed at 12–19 kbar, lies on the UHPM rocks. We suggest that this serpentinite melange represents a highly attenuated upper mantle section that structurally overlay the UHP rocks during subduction. Similar serpentinite melanges are known from other high-pressure (HP) and UHPM areas and may have a similar origin.

Contrasting serpentinization processes in the eastern Central Alps

USGS Publications Warehouse

Burkhard, D.J.M.; O'Neil, J.R.

1988-01-01

Stable isotope compositions have been determined for serpentinites from between Davos (Arosa-Platta nappe, Switzerland) and the Valmalenco (Italy). ??D and ??18O values (-120 to -60 and 6-10???, respectively) in the Arosa-Platta nappe indicate that serpentinization took place on the continent at relatively low temperatures in the presence of limited amounts of metamorphic fluids that contained a component of meteoric water. One sample of chrysotile has a ??18O value of 13??? providing evidence of high W/R ratios and low formation temperature of lizardite-chrysotile in this area. In contrast, relatively high ??D values (-42 to -34???) and low ??18O values (4.4-7.4???) for serpentine in the eastern part of the Valmalenco suggest a serpentinization process that took place at moderate temperatures in fluids that were dominated by ocean water. The antigorite in the Valmalenco is the first reported example of continental antigorite with an ocean water signature. An amphibole sample from a metasomatically overprinted contact zone to metasediments (??D=-36???) indicates that the metasomatic event also took place in the presence of ocean water. Lower ??D values (-93 to -60???) of serpentines in the western part of the Valmalenco suggest a different alteration history possibly influenced by fluids associated with contact metamorphism. Low water/rock ratios during regional metamorphism (and metasomatism) have to be assumed for both regions. ?? 1988 Springer-Verlag.

Slab detachment under the Eastern Alps seen by seismic anisotropy

PubMed Central

Qorbani, Ehsan; Bianchi, Irene; Bokelmann, Götz

2015-01-01

We analyze seismic anisotropy for the Eastern Alpine region by inspecting shear-wave splitting from SKS and SKKS phases. The Eastern Alpine region is characterized by a breakdown of the clear mountain-chain-parallel fast orientation pattern that has been previously documented for the Western Alps and for the western part of the Eastern Alps. The main interest of this paper is a more detailed analysis of the anisotropic character of the Eastern Alps, and the transition to the Carpathian–Pannonian region. SK(K)S splitting measurements reveal a rather remarkable lateral change in the anisotropy pattern from the west to the east of the Eastern Alps with a transition area at about 12°E. We also model the backazimuthal variation of the measurements by a vertical change of anisotropy. We find that the eastern part of the study area is characterized by the presence of two layers of anisotropy, where the deeper layer has characteristics similar to those of the Central Alps, in particular SW–NE fast orientations of anisotropic axes. We attribute the deeper layer to a detached slab from the European plate. Comparison with tomographic studies of the area indicates that the detached slab might possibly connect with the lithosphere that is still in place to the west of our study area, and may also connect with the slab graveyard to the East, at the depth of the upper mantle transition zone. On the other hand, the upper layer has NW–SE fast orientations coinciding with a low-velocity layer which is found above a more-or-less eastward dipping high-velocity body. The anisotropy of the upper layer shows large-scale NW–SE fast orientation, which is consistent with the presence of asthenospheric flow above the detached slab foundering into the deeper mantle. PMID:25843968

Slab detachment under the Eastern Alps seen by seismic anisotropy

NASA Astrophysics Data System (ADS)

Qorbani, Ehsan; Bianchi, Irene; Bokelmann, Götz

2015-01-01

We analyze seismic anisotropy for the Eastern Alpine region by inspecting shear-wave splitting from SKS and SKKS phases. The Eastern Alpine region is characterized by a breakdown of the clear mountain-chain-parallel fast orientation pattern that has been previously documented for the Western Alps and for the western part of the Eastern Alps. The main interest of this paper is a more detailed analysis of the anisotropic character of the Eastern Alps, and the transition to the Carpathian-Pannonian region. SK(K)S splitting measurements reveal a rather remarkable lateral change in the anisotropy pattern from the west to the east of the Eastern Alps with a transition area at about 12°E. We also model the backazimuthal variation of the measurements by a vertical change of anisotropy. We find that the eastern part of the study area is characterized by the presence of two layers of anisotropy, where the deeper layer has characteristics similar to those of the Central Alps, in particular SW-NE fast orientations of anisotropic axes. We attribute the deeper layer to a detached slab from the European plate. Comparison with tomographic studies of the area indicates that the detached slab might possibly connect with the lithosphere that is still in place to the west of our study area, and may also connect with the slab graveyard to the East, at the depth of the upper mantle transition zone. On the other hand, the upper layer has NW-SE fast orientations coinciding with a low-velocity layer which is found above a more-or-less eastward dipping high-velocity body. The anisotropy of the upper layer shows large-scale NW-SE fast orientation, which is consistent with the presence of asthenospheric flow above the detached slab foundering into the deeper mantle.

Consistent earthquake catalog derived from changing network configurations: Application to the Rawil Depression in the southwestern Helvetic Alps

NASA Astrophysics Data System (ADS)

Lee, Timothy; Diehl, Tobias; Kissling, Edi; Wiemer, Stefan

2017-04-01

Earthquake catalogs derived from several decades of observations are often biased by network geometries, location procedures, and data quality changing with time. To study the long-term spatio-temporal behavior of seismogenic fault zones at high-resolution, a consistent homogenization and improvement of earthquake catalogs is required. Assuming that data quality and network density generally improves with time, procedures are needed, which use the best available data to homogeneously solve the coupled hypocenter - velocity structure problem and can be as well applied to earlier network configurations in the same region. A common approach to uniformly relocate earthquake catalogs is the calculation of a so-called "minimum 1D" model, which is derived from the simultaneous inversion for hypocenters and 1D velocity structure, including station specific delay-time corrections. In this work, we will present strategies using the principles of the "minimum 1D" model to consistently relocate hypocenters recorded by the Swiss Seismological Service (SED) in the Swiss Alps over a period of 17 years in a region, which is characterized by significant changes in network configurations. The target region of this study is the Rawil depression, which is located between the Aar and Mont Blanc massifs in southwestern Switzerland. The Rhone-Simplon Fault is located to the south of the Rawil depression and is considered as a dextral strike-slip fault representing the dominant tectonic boundary between Helvetic nappes to the north and Penninic nappes to the south. Current strike-slip earthquakes, however, occur predominantly in a narrow, east-west striking cluster located in the Rawil depression north of the Rhone-Simplon Fault. Recent earthquake swarms near Sion and Sierre in 2011 and 2016, on the other hand, indicate seismically active dextral faults close to the Rhone valley. The region north and south of the Rhone-Simplon Fault is one of the most seismically active regions in

The nappes of the Lepontine dome: the influence of tectonic inheritance on their deformation style

NASA Astrophysics Data System (ADS)

Schenker, Filippo Luca; Ambrosi, Christian; Scapozza, Cristian; Czerki, Dorota; Castelletti, Claudio; Maino, Matteo; Gouffon, Yves

2017-04-01

The Lepontine dome exposes the tectonostratigraphy of the Central Alps, from bottom-to-top, the subpenninic gneissic nappes of the Leventina, Simano, Adula/Cima-Lunga and Maggia. These units were part of a post-Variscan gneissic crust, which was intensely intruded by several generations of granitoids forming laccoliths and dikes of different shapes and sizes within paragneisses, augengneisses and amphibolites. During the Alpine orogenic cycle this initial and complex geological architecture was reshaped into a fold and thrust belt. We present the effect of these initial rheological anomalies along the Leventina, Simano and Adula/Cima-Lunga units through the geological map of the Osogna sheet (Swiss National Map no. 1293,1:25'000) together with structural and metamorphic data. The geological map shows that the Simano and Adula/Cima-Lunga units have an internal and lateral lithological variation at different scales as illustrated by the geological cross-sections. All lithologies present a penetrative amphibolite-facies foliation, which can vary in intensity among the rock-types. On the foliation plane a mineral and stretching lineation is visible dipping NW or SE, depending on the plane dip direction. The kinematic analysis indicates a top-to-the NW shearing. Despite this consistent structural data showing a regional dominant fabric, the folds (generally with a fold-axis parallel to the lineation) show different styles, depending on the thickness and the rock-type of the folded horizon and matrix, do not form laterally continuous structures and often are not cylindrical. As a consequence, such structures are interpreted as local perturbation rather than structures of regional importance. Furthermore, the Leventina and the Simano boundary is locally incongruent with the tectonic contact of the published maps. The amphibolite and paragneisses, used in the past as nappe divider, result to be deformed magmatic xenoliths. Therefore we present evidence (i) of a bottom

Contrasting serpentinization processes in the eastern Central Alps

NASA Astrophysics Data System (ADS)

Burkhard, Dorothee J. M.; O'Neil, James R.

1988-08-01

Stable isotope compositions have been determined for serpentinites from between Davos (Arosa-Platta nappe, Switzerland) and the Valmalenco (Italy). δD and δ 18O values (-120 to -60 and 6 10‰, respectively) in the Arosa-Platta nappe indicate that serpentinization took place on the continent at relatively low temperatures in the presence of limited amounts of metamorphic fluids that contained a component of meteoric water. One sample of chrysotile has a δ 18O value of 13‰ providing evidence of high W/R ratios and low formation temperature of lizardite-chrysotile in this area. In contrast, relatively high δD values (-42 to -34‰) and low δ 18O values (4.4 7.4‰) for serpentine in the eastern part of the Valmalenco suggest a serpentinization process that took place at moderate temperatures in fluids that were dominated by ocean water. The antigorite in the Valmalenco is the first reported example of continental antigorite with an ocean water signature. An amphibole sample from a metasomatically overprinted contact zone to metasediments ( δD=-36‰) indicates that the metasomatic event also took place in the presence of ocean water. Lower δD values (-93 to -60‰) of serpentines in the western part of the Valmalenco suggest a different alteration history possibly influenced by fluids associated with contact metamorphism. Low water/rock ratios during regional metamorphism (and metasomatism) have to be assumed for both regions.

On the age of sinistral shearing along the southern border of the Tauern Window (Eastern Alps).

NASA Astrophysics Data System (ADS)

Kitzig, C.; Schneider, S.; Hammerschmidt, K.

2009-04-01

The first-order structure of the western Tauern Window consists of three upright, ENE-striking antiforms of large amplitude, whose flanks are overprinted by sinistral shear zones, striking parallel to the axial planes of the antiforms. Analogue modelling suggests that these shear zones accommodate part of the shortening of the South Alpine indenter (Rosenberg et al., 2004). The age of sinistral shearing in the western Tauern Window and immediately south of it is still controversial. Mancktelow et al. (2001) suggested that sinistral shearing at the southern border of the Tauern Window terminated at 30 Ma. Based on monazite spot dates ranging between 29.0-20.3 Ma (n=10) of dextral shear zones, which cross-cut the sinistral Greiner shear zone, Barnes et al. (2004) argued that the switch from sinistral to dextral shear occurred shortly after the thermal peak of the Alpine orogeny (c.~ 30 Ma). Recent dating of mica-bearing marble suggested that the activity of the southernmost sinistral shear zone of the Tauern Window (the Ahrntal shear zone) was 19.8±0.4 Ma ago (Glodny et al. 2008). Sinistral shearing is commonly interpreted as part of the 2nd Alpine phase of deformation that affected the Tauern Window. The main foliation (S1) of the Tauern Window was acquired during a first phase, which resulted in the present day nappe stack. Only along some of the later shear zones a second Alpine foliation (S2) was formed. At present no attempt has been made, to distinguish the two and directly date the S2 mylonitic foliation. In the present work we use the Rb/Sr method to date mineral pairs formed under greenschist to lower amphibolite facies conditions from the tonalitic Zentral Gneiss. We dated four samples, two from the inferred undeformed tonalite protolith, one from the strongly foliated tonalitic gneiss and one from an outcrop-scale sinistral shear zone within the foliated tonalitic gneiss. Generally biotite and feldspar define isochrones for the four samples. The

Changing patterns of exhumation and denudation in front of an advancing crustal indenter, Tauern Window (Eastern Alps)

NASA Astrophysics Data System (ADS)

Favaro, S.; Handy, M. R.; Scharf, A.; Schuster, R.

2017-06-01

The changing shape of indenting crustal blocks during northward motion of the Adriatic microplate induced migration of Miocene doming and orogen-parallel extension of orogenic crust in the Tauern Window. New structural and kinematic data indicate that initial shortening of the Penninic nappe pile in the Tauern Window by upright folding and strike-slip faulting was transitional to coeval north-south shortening and east-west extension; the latter was accommodated by normal faulting at the eastern and western margins of the window. Retrodeforming these post-nappe structures in map view yields a map-view reconstruction of the orogenic crust back to 30 Ma, including the onset of pronounced indentation at 21 Ma. This model supports the notion that indentation involved approximately equal amounts of north-south shortening and orogen-parallel stretching and extrusion toward the Pannonian Basin, as measured from the indenter tip to the European foreland in the north and Austroalpine units in the east. Comparison of areal denudation of the orogenic crust before and after indentation indicates that erosion associated with upright folding was the primary agent of denudation, whereas extensional unroofing and limited erosion along normal faults at the eastern and western ends of the Tauern Window accounted for only about a third of the total denudation.

Consistent Top-to-the-foreland Directed Deformation from Floor to Roof in the Seve Nappe Complex (SNC), Jämtland, Sweden

NASA Astrophysics Data System (ADS)

Bender, H.; Ring, U.; Almqvist, B. S. G.; Glodny, J.; Grasemann, B.; Stephens, M. B.

2016-12-01

The recent COSC-1 drilling programme (Lorenz et al., 2015), discovery of microdiamonds (Majka et al., 2014) and discussion of extrusion-wedge tectonics (Grimmer et al., 2015) outline the importance of the Seve Nappe Complex (SNC) and its key role during the Caledonian orogeny. The kinematic evolution of the SNC is crucial for better understanding the entire mountain belt. Thorough structural mapping of the SNC and adjacent units was conducted in western and northern Jämtland, central Sweden. Complementary microstructural investigations strengthen the field observations and show consistent top-to-the-SE directed movement through all studied tectonic units. Amphibolite-facies deformation can be inferred from fabrics in the SNC, which are overprinted by greenschist-facies structures showing the same kinematics throughout the studied section of the nappe stack. These data indicate persistence of the same foreland-directed kinematics over a wide range of pressure-temperature conditions in space and time. Currently proposed models for exhuming high-grade metamorphic rocks in collisional orogens fail to explain these observations and highlight the need for discussing new tectonic concepts for the Scandinavian Caledonides. References: Grimmer et al., 2015, Geology 43 (4); Lorenz et al., 2015, Scientific Drilling 19; Majka et al. 2014, Geology 42 (12).

Review of metamorphic and kinematic data from Internal Crystalline Massifs (Western Alps): PTt paths and exhumation history

NASA Astrophysics Data System (ADS)

Gasco, Ivano; Gattiglio, Marco; Borghi, Alessandro

2013-01-01

Detailed geological mapping combined with micro-structural and petrological investigation allowed to clarify the tectono-metamorphic relationships between continental and oceanic units transition in the Penninic domain of the Western Alps. The three study areas (Gressoney, Orco and Susa sections) take into consideration the same structural level across the axial metamorphic belt of the Western Italian Alps, i.e., a geological section across the Internal Crystalline Massifs vs Piedmont Zone boundary. The units outcropping in these areas can be grouped into two Tectonic Elements according to their tectono-metamorphic evolution. The Lower Tectonic Element (LTE) consists of the Internal Crystalline Massifs and the Lower Piedmont Zone (Zermatt-Saas like units), both showing well preserved eclogite facies relics. Instead, the Upper Tectonic Element (UTE) consists of the Upper Piedmont Zone (Combin like units) lacking evidence of eclogite facies relics. In the Lower Tectonic Element two main Alpine tectono-metamorphic stages were identified: M1/D1 developed under eclogite facies conditions and M2/D2 is related to the development of the regional foliation under greenschist to epidote-albite amphibolite facies conditions. In the Upper Tectonic Element the metamorphic stage M1/D1 developed under bluschist to greenschist facies conditions and M2/D2 stage under greenschist facies conditions. These two Tectonic Elements are separated by a tectonic contact of regional importance generally developed along the boundary between the Lower and the Upper Piedmont zone under greenschist facies conditions. PT data compared to geochronology indicate that the first exhumation of ICM can be explained by buoyancy forces acting along the subduction channel that occurred during the tectonic coupling between the continental and oceanic eclogite units. These buoyancy forces vanished at the base of the crust where the density difference between the subducted crustal units and the surroundings

Differential Properties of Human ALP+ Periodontal Ligament Stem Cells vs Their ALP- Counterparts

PubMed Central

Tran, Quynh T; El-Ayachi, Ikbale; Bhatti, Fazal-Ur-Rehman; Bahabri, Rayan; Al-Habib, Mey; Huang, George TJ

2015-01-01

Characterizing subpopulations of stem cells is important to understand stem cell properties. Tissue-nonspecific alkaline phosphatase (ALP) is associated with mineral tissue forming cells as well as stem cells. Information regarding ALP subpopulation of human periodontal ligament stem cells (hPDLSCs) is limited. In the present study, we examined ALP+ and ALP− hPDLSC subpopulations, their surface markers STRO-1 and CD146, and the expression of stemness genes at various cell passages. We found that ALP+ subpopulation had higher levels of STRO-1 (30.6 ± 5.6%) and CD146 (90.4 ± 3.3%) compared to ALP− (STRO-1: 0.5 ± 0.1%; CD146: 75.3 ± 7.2%). ALP+ cells expressed significantly higher levels of stemness associated genes, NANOG, OCT4 and SOX than ALP− cells at low cell passages of 2-3 (p<0.05). ALP+ and ALP− cells had similar osteogenic, chondrogenic and neurogenic potential while ALP−, not ALP+ cells, lacked adipogenic potential. Upon continuous culturing and passaging, ALP+ continued to express higher stemness genes and STRO-1 and CD146 than ALP− cells at ≥passage 19. Under conditions (over-confluence and vitamin C treatment) when ALP+ subpopulation was increased, the stemness gene levels of ALP+ was no longer significantly higher than those in ALP− cells. In conclusion, ALP+ hPDLSCs possess differential properties from their ALP− counterparts. PMID:26807329

How steep are the Alps?

NASA Astrophysics Data System (ADS)

Robl, Jörg; Prasicek, Günther; Stüwe, Kurt; Hergarten, Stefan

2014-05-01

time and process rates in transient landscapes are predominantly governed by the lithological inventory. Areas belonging to the same structural unit show similar characteristics in the slope-elevation distribution independent from their spatial position within the orogen (e.g. external massifs). These similarities are probably caused by the vertical position of the Pleistocene equilibrium line altitude - an observation well in line with the glacial "buzz saw" hypothesis. However, several non-glaciated regions at the eastern and south-western border of the Alps show a slope-elevation relation similar to formerly glaciated domains. However, in contrast to the glaciated realm, the inflection point in the slope-elevation distribution is located at various elevation levels and is consistent with a reported recent pulse of uplift with spatial and/or temporal variations in uplift rate and initiation. Therefore, we interpret the slope-elevation distribution of the European Alps to be mainly caused by glacial erosion. The morphological record of a recent uplift event in the Alps has probably been overprinted by Pleistocene glaciations and may therefore only be detectable in non-glaciated regions of the peripheral parts of the Alps and in subsurface structures.

3D modelling of the Austroalpine-Penninic collisional wedge of the NW Alps: dataset management and preliminary results

NASA Astrophysics Data System (ADS)

Monopoli, Bruno; Bistacchi, Andrea; Bertolo, Davide; Dal Piaz, Giovanni; Gouffon, Yves; Massironi, Matteo; Sartori, Mario; Vittorio Dal Piaz, Giorgio

2016-04-01

We know since the beginning of the 20th century, thanks to mapping and structural studies by the Italian Regio Servizio Geologico (Franchi et al., 1908) and Argand's work (1909; 1911; 1916), that the Austroalpine-Penninic collisional wedge of the NW Alps is spectacularly exposed across the Aosta Valley and Valais ranges (Italy and Switzerland). In the 150th anniversary of the first ascent to Ruskin's "most noble cliff in Europe" - the Cervino/Matterhorn (Whymper, July 14th 1865), first described in a geological profile by Giordano (1869) and in a detailed map by Gerlach (1869; 1871), we have seen the conclusion of very detailed mapping projects carried out in the last years over the two regions, with collaborative efforts across the Italy-Switzerland border, constellated by 4000 m-high peaks. These projects have pictured with an unprecedented detail (up to 1:10.000 scale) the geology of this complex region, resulting from pre-Alpine events, Alpine subduction- and collision-related ductile deformations, and finally late-Alpine brittle deformations from the Oligocene to the Present. Based on this dataset, we use up-to-date technology and software to undertake a 3D modelling study aimed at: i) reconstructing the 3D geometry of the principal tectonic units, ii) detecting and unravelling problems and incongruences in the 2D geometrical models, iii) modelling the kinematics of the Oligocene and Miocene brittle fault network using 2D and 3D balancing and palinspastic restoration techniques. In this contribution we mainly discuss the prerequisites of the project. Common geomodelling paradigms (mainly developed for the hydrocarbon industry) cannot be applied in this project due to (i) the little scale, (ii) the source of the data - fieldwork, and (iii) the polyphase ductile and brittle deformations in the metamorphic nappe stack. Our goals at the moment are to model the post-metamorphic fault network and the boundaries of the principal tectonic units, which will be

The Schistes à Blocs Fm: the ultimate member of the Annot Sandstones in the Southern Alps (France); slope gullies or canyon system?

NASA Astrophysics Data System (ADS)

Rubino, Jean-Loup; Mercier, Louison; Daghdevirenian, Laurent; Migeon, Sébastien; Bousquet, Romain; Broucke, Olivier; Raisson, Francois; Joseph, Philippe; Deschamp, Remi; Imbert, Patrice

2017-04-01

Described since a long time, the Schistes à Blocs Fm is the ultimate member of the famous tertiary Grès d'Annot Sandstones in southern alpine foredeep basin in SE France. It mainly consists of shales, silty shales, debris flows, olistoliths and a subordinate amount of sandstones. Since their introduction, and because of their location down to major thrust sheet, they have been considered as a tectono-sedimentary unit linked to the nappe's emplacement and refer as an olistostrome, (Kerckove 1964-1969). However they are separated from the underlying Annot Sandstones by a major erosional surface which deeply cuts, up to 500m, into the sandy turbidites; this surface definitively predates the infill and the nappe emplacement. This is supported by the fact that imbricates affect the upper part of the Schistes and also because of the age; the Schistes à Blocs being Upper Eocene to Lower Oligocene whilst the nappe is latest Oligocene to Lower Miocene. A detailed analysis of the erosional surface in la Bonette area reveals a complex geometry which shows obvious similarities with these observed either on submarine canyons or in slope dissected by gullies as shown by numerous seabeams or 3D seismic images. The infill is quite complex, no basal lag have been observed, however bioturbations suggest occurrence of by pass. Most commonly the lower part of the infill is made of muddy or silty sediments. In some areas, decametric to pluri hectometric olistoliths are interbedded within these deposits. Debris flows are also common with a muddy matrix and finally isolated turbidite channels including the same material than in the Annot Sandstones occur. The reworked material into the debris flows and in the olistoliths suggests that it doesn't only derived from canyon flanks (sandstones) but includes elements belonging to older tethyan series such as Triassic and Liassic carbonates which must be exposed on the sea floor on local highs in the more internal part of the Alps but much

Seismic anisotropy and large-scale deformation of the Eastern Alps

NASA Astrophysics Data System (ADS)

Bokelmann, Götz; Qorbani, Ehsan; Bianchi, Irene

2013-12-01

Mountain chains at the Earth's surface result from deformation processes within the Earth. Such deformation processes can be observed by seismic anisotropy, via the preferred alignment of elastically anisotropic minerals. The Alps show complex deformation at the Earth's surface. In contrast, we show here that observations of seismic anisotropy suggest a relatively simple pattern of internal deformation. Together with earlier observations from the Western Alps, the SKS shear-wave splitting observations presented here show one of the clearest examples yet of mountain chain-parallel fast orientations worldwide, with a simple pattern nearly parallel to the trend of the mountain chain. In the Eastern Alps, the fast orientations do not connect with neighboring mountain chains, neither the present-day Carpathians, nor the present-day Dinarides. In that region, the lithosphere is thin and the observed anisotropy thus resides within the asthenosphere. The deformation is consistent with the eastward extrusion toward the Pannonian basin that was previously suggested based on seismicity and surface geology.

Virtual tours as a new teaching tool in geoscience: an example from the Western Alps

NASA Astrophysics Data System (ADS)

Berger, Antoine; Champagnac, Jean-Daniel; Nomade, Jérome

2013-04-01

, these panorama can be linked together to travel from place to place. Last, but not least, the display of any type of information (video of the last year teachers' explanation, close up of a structure, graphic plot, text content, interpreted geological sections etc.) can be integrated in the virtual tour. From this, it is easy to build a full educational virtual tour that can include the information provided in the field book, and even become the field book itself. These virtual tours can be used with any device (laptop, tablet, smartphone...), hence have the potential become key players in field teaching. Finally, these virtual tours can help physically impaired students to complete their geological curriculum with the indispensable field experience they would not have had otherwise. Here we present an example of such a virtual tour build in 2012 across the European Alps during the 1st International Field Course organized by Grenoble University, ETH Zürich and Milano University. This virtual tour covers the Grimsel Pass Aar Massif Hercynian Basement (granite, shear zone and the underground NAGRA test site), the Zermatt area (two continents and two oceans packed together), the Aiguille du Midi incredible overview on most of the W-Alps, and the back limb of the Nappe de Morcles and its relation with the surrounding blocks. Link to the virtual tour: http://www.alpesphoto.com/temp/visites/Suisse/build/virtualtour.swf

6-kyr record of flood frequency and intensity in the western Mediterranean Alps - Interplay of solar and temperature forcing

NASA Astrophysics Data System (ADS)

Sabatier, Pierre; Wilhelm, Bruno; Ficetola, Gentile Francesco; Moiroux, Fanny; Poulenard, Jérôme; Develle, Anne-Lise; Bichet, Adeline; Chen, Wentao; Pignol, Cécile; Reyss, Jean-Louis; Gielly, Ludovic; Bajard, Manon; Perrette, Yves; Malet, Emmanuel; Taberlet, Pierre; Arnaud, Fabien

2017-08-01

The high-resolution sedimentological and geochemical analysis of a sediment sequence from Lake Savine (Western Mediterranean Alps, France) led to the identification of 220 event layers for the last 6000 years. 200 were triggered by flood events and 20 by underwater mass movements possibly related to earthquakes that occurred in 5 clusters of increase seismicity. Because human activity could influence the flood chronicle, the presence of pastures was reconstructed through ancient DNA, which suggested that the flood chronicle was mainly driven by hydroclimate variability. Weather reanalysis of historical floods allow to identify that mesoscale precipitation events called "East Return" events were the main triggers of floods recorded in Lake Savine. The first part of this palaeoflood record (6-4 kyr BP) was characterized by increases in flood frequency and intensity in phase with Northern Alpine palaeoflood records. By contrast, the second part of the record (i.e., since 4 kyr BP) was phased with Southern Alpine palaeoflood records. These results suggest a palaeohydrological transition at approximately 4 kyr BP, as has been previously described for the Mediterranean region. This may have resulted in a change of flood-prone hydro-meteorological processes, i.e., in the balance between occurrence and intensity of local convective climatic phenomena and their influence on Mediterranean mesoscale precipitation events in this part of the Alps. At a centennial timescale, increases in flood frequency and intensity corresponded to periods of solar minima, affecting climate through atmospheric changes in the Euro-Atlantic sector.

Large scale displacements and internal deformations of the Outer Western Carpathians during the Cenozoic as manifested in paleomagnetic rotations and in the magnetic fabrics

NASA Astrophysics Data System (ADS)

Márton, Emö; Tokarski, Antek K.

2016-04-01

The paleomagnetic and magnetic anisotropy results interpreted in this presentation in terms of tectonics were obtained on the fine grained members, mostly mudstones/claystones, of the flysch from the Magura, the Silesian and the Dukla rootless nappes. The results are the best from the Upper Oligocene Krosno beds, which were affected by compression soon after deposition. These beds were available for sampling in the Silesian and Dukla nappes, but absent in the Magura nappe. Thus, in the latter older Paleogene strata were tested. A common feature of all sampled sediments is the low susceptibility (in the range of 10-4 SI or lower), weak remanence and the presence of pyrite. AMS measurements point to quite strong and probably repeated deformation in the Magura nappe, and the remanence is of-post-folding age. The AMS of the Silesian and Dukla nappes indicate weaker deformation, the orientations of the AMS lineations reflect compression. The remanence is of pre-folding age in the western and central segments of the Silesian nappe and is a mixture of pre and post-folding magnetization in the eastern segment. All the so far mentioned areas must have been affected by about 60° CCW rotation which followed the internal deformation. The Dukla nappe also rotated in the CCW sense, but the angle is far from well-defined. This can be attributed to the complicated internal structure of the nappe (e.g. presence of olistoliths) and non-removable overprint magnetizations. The relationship between local tectonic strikes and AMS lineations seems to imply that the ductile deformation responsible for the AMS lineations were acquired first, and the map-scale structures came into being during the CCW rotation of the studied segment of the nappe. AARM measurements documented that the fabrics of the ferrimagnetic minerals are often different from the orientation of the AMS fabrics. In such cases, they either fail to define an ellipsoid or the general orientations of the maxima are different

Pressure - temperature estimates of a phengite eclogite from the Grapesvåre Nappe, Norrbotten, Swedish Caledonides

NASA Astrophysics Data System (ADS)

Bukała, Michał; Majka, Jarosław; Walczak, Katarzyna; Barnes, Christopher; Klonowska, Iwona

2017-04-01

The Seve Nappe Complex (SNC) of the Scandinavian Caledonides has well documented history of high pressure (HP) and ultra-high pressure (UHP) metamorphism (e.g. Klonowska et al. 2014). Eclogites of the SNC occur in two areas in Sweden, namely Jämtland and Norrbotten. The Jämtland eclogites and associated rocks are well studied and provide evidence for the Late Ordovician UHP metamorphism, whereas the Norrbotten eclogites, formed during the Late Cambrian/Early Ordovician, have not been studied in detail, especially in terms of pressure-temperature (P-T) conditions of their formation. Within the SNC in Norrbotten, eclogites are limited to two tectonic lenses - Vaimok and Tsäkkok (e.g. Albrecht, 2000). Within the Vaimok Lens three nappes have been distinguished: (1) the eclogite-free Lower Seve Nappe, (2) the Grapesvåre Nappe and (3) the Maddåive Nappe. The two latter nappes are eclogite-bearing. For this study eclogites were collected from the lowermost part of the Grapesvåre Nappe (from the highly heterogeneous Daunasvagge unit dominated by garnet-bearing mica schists, quartzites and marbles). Eclogite boudins (former dolerite dikes and sills) are usually highly altered due to retrogressive recrystallization. Rare fresh eclogites occur within large boudins (>5m in diameter) and display only minor alteration limited to the scarce veinlets composed of amphibole + feldspar + garnet + zoisite + biotite + rutile + titanite. Metamorphic peak conditions mineral assemblage consists of garnet + omphacite + phengite + quartz + rutile. For P-T estimates the geothermobarometric method of Ravna & Terry (2004) has been used. The garnet-clinopyroxene Fe2+-Mg exchange thermometer and the net-transfer reaction barometer based on the garnet-phengite-omphacite equilibrium yielded a maximum pressure of 26.7 kbar and temperature of 677°C. The obtained temperature might be underestimated due to uncertainties in Fe2+/Fe3+ ratio in pyroxene. Therefore Zr-in-rutile geothermometer by

No erosional control on the lateral growth of the Alps

NASA Astrophysics Data System (ADS)

Rosenberg, C. L.; Berger, A.

2009-04-01

of the deformation front of the Jura Mountains (Nivière and Winter, 2000; Giamboni et al., 2004; Madritsch et al., 2008), the westward shift of the Chaines Subalpines (Lickorisch and Ford, 1998) on the western side of the orogen, and the southward migration of the active front in the eastern sector of the Southern Alps (Benedetti et al., 2000). The reduced erosional efficiency of the orogen, which started at 17 Ma and continued until the Messinian (Kuhlemann, 2000) also did not coincide to a phase of lateral growth of the orogen. Out-of sequence thrusting in the Southern Alps (Schönborn, 1992) reduced the width of the chain well before the Messinian crisis, i.e. during the phase of fading erosion efficiency. Therefore, erosion does not seem to have been the prime control on the changes of width of the orogen. Alternatively, the effect of erosion on the lateral growth of the orogen can be tested by comparing the timing and the type of shifts of the active deformation front from different parts of the orogen. If climate changes are inferred to control changes in the erosional efficiency of the Alps (Willett et al., 2006), the tectonic response to a given change of climate is expected to be coeval and of similar type in all parts of the chain. This is especially true for an orogen as small as the Alps, whose different portions are all affected by the same climatic conditions. However, the mode of exhumation of the Eastern Alps is very different than that of the Western and Central Alps. The exhumation front progressively shifted towards the foreland in the latter case, whereas it remained focused in the axial zone of the orogen in the former case (Rosenberg and Berger, 2009). As a consequence, a broad metamorphic belt, with cooling ages younging from the axial zone towards the foreland formed in the western Alps, and a narrow metamorphic belt with cooling ages younging towards the axial zone of the orogen formed in the Eastern Alps. These first-order differences

Relation between grain size and modal composition in deep-sea gravity-flow deposits. Example from the Voirons Flysch (Gurnigel nappe, Chablais Prealps, France)

NASA Astrophysics Data System (ADS)

Ragusa, Jérémy; Kindler, Pascal

2016-04-01

A coupled analysis of modal composition, grain size and sedimentary features of gravity-flow deposits in the Gurnigel nappe shows that the transition from coarse proximal to fine distal deposits is accompanied by a change in composition from siliciclastic to calcareous. Such compositional variation should be taken into account when interpretating deep-sea deposits if sampling is restricted to a single part of the fan. The Chablais Prealps (Haute-Savoie, France) represent a well-preserved accretionary wedge in the Western Alps. They comprise a stack of northward-thrusted sedimentary cover nappes originating from the Ultrahelvetic realm (distal part of the European margin) to the southern part of the Piemont Ocean. The present study focuses on the Voirons Flysch, belonging to the Gurnigel nappe, which includes four formations consisting of gravity-flow deposits (from bottom to top): (1) the Voirons Sandstone Fm., composed of channel to lobe deposits; (2) the Vouan Conglomerate Fm., represented by the proximal part of a channel system; (3) the Boëge Marls Fm., constituted by distal lobe deposits; finally, (4) the Bruant Sandstone Fm., which consists in channel to lobe deposits. Recent biostratigraphic results using planktonic foraminifers attributed a Middle to Late Eocene age to the Voirons Flysch, which was formerly believed to range from the Paleocene to the Middle Eocene (based on calcareous nannofossils). A total of 270 thin sections with stained feldspars were prepared, representing the four formations of the Voirons Flysch. Circa 300 extrabasinal grains were counted per thin section using the classic Indiana method. In addition, the quantity of intrabasinal grains (i.e. bioclasts, glauconite), cement and porosity was analysed. Cement was stained with alizarine and potassium ferrocyanide. 200 grain-size measurements on ca. 100 samples were performed using 3D conversion and statistical moment analysis. Sedimentary observations for each sampled bed were

Study geomorphology, past and present, linear trench, tectonics relationship between Pyrenees and Alps

NASA Technical Reports Server (NTRS)

Guillemot, J. (Principal Investigator)

1974-01-01

The author has identified the following significant results. ERTS-1 images obviously show up some large linear features trending N 80 E or N 30 E common to both Alps and Pyrenees. One of them, the Ligurian Fault, had been previously forecast by Laubscher in an interpretation of the Alps by the plate tectonic theory, but it extends westward farthest from the Alps, cutting the Pyrenees axis. These lineaments have been interpreted as reflections of deep seated wrench faults in the surficial part of the sedimentary series. A large set of such lineaments is perceptible in western Europe, such as the Guadalquivir Fault in southern Spain, Ligurian Fault, Insubrian Fault, Northern-Jura Fault, Metz Fault. Perhaps these may be interpreted as transform faults of the mid-Atlantic ridge or of a paleo-rift seated in the Rhine-Rhone graben.

Cathodoluminescence, fluid inclusion and stable C-O isotope study of tectonic breccias from thrusting plane of a thin-skinned calcareous nappe

NASA Astrophysics Data System (ADS)

Milovský, Rastislav; van den Kerkhof, Alfons; Hoefs, Jochen; Hurai, Vratislav; Prochaska, Walter

2012-03-01

Basal hydraulic breccias of alpine thin-skinned Muráň nappe were investigated by means of cathodoluminescence petrography, stable isotope geochemistry and fluid inclusions analysis. Our study reveals an unusual dynamic fluid regime along basal thrust plane during final episode of the nappe emplacement over its metamorphic substratum. Basal thrusting fluids enriched in 18O, silica, alumina, alkalies and phosphates were generated in the underlying metamorphosed basement at epizonal conditions corresponding to the temperatures of 400-450°C. The fluids fluxed the tectonized nappe base, leached evaporite-bearing formations in hangingwall, whereby becoming oversaturated with sulphates and chlorides. The fluids further modified their composition by dedolomitization and isotopic exchange with the host carbonatic cataclasites. Newly formed mineral assemblage of quartz, phlogopite, albite, potassium feldspar, apatite, dravite tourmaline and anhydrite precipitated from these fluids on cooling down to 180-200°C. Finally, the cataclastic mush was cemented by calcite at ambient anchizonal conditions. Recurrent fluid injections as described above probably enhanced the final motion of the Muráň nappe.

Stress field variations in the Swiss Alps and the northern Alpine foreland derived from inversion of fault plane solutions

USGS Publications Warehouse

Kastrup, U.; Zoback, M.L.; Deichmann, N.; Evans, Kenneth F.; Giardini, D.; Michael, A.J.

2004-01-01

This study is devoted to a systematic analysis of the state of stress of the central European Alps and northern Alpine foreland in Switzerland based on focal mechanisms of 138 earthquakes with magnitudes between 1 and 5. The most robust feature of the results is that the azimuth of the minimum compressive stress, S3, is generally well constrained for all data subsets and always lies in the NE quadrant. However, within this quadrant, the orientation of S3 changes systematically both along the structural strike of the Alpine chain and across it. The variation in stress along the mountain belt from NE to SW involves a progressive, counterclockwise rotation of S3 and is most clear in the foreland, where it amounts to 45??-50??. This pattern of rotation is compatible with the disturbance to the stress field expected from the indentation of the Adriatic Block into the central European Plate, possibly together with buoyancy forces arising from the strongly arcuate structure of the Moho to the immediate west of our study area. Across the Alps, the variation in azimuth of S3 is defined by a progressive, counterclockwise rotation of about 45?? from the foreland in the north across the Helvetic domain to the Penninic nappes in the south and is accompanied by a change from a slight predominance of strike-slip mechanisms in the foreland to a strong predominance of normal faulting in the high parts of the Alps. The observed rotation can be explained by the perturbation of the large-scale regional stress by a local uniaxial deviatoric tension with a magnitude similar to that of the regional differential stress and with an orientation perpendicular to the strike of the Alpine belt. The tensile nature and orientation of this stress is consistent with the "spreading" stress expected from lateral density changes due to a crustal root beneath the Alps. Copyright 2004 by the American Geophysical Union.

Interdependency of fission yeast Alp14/TOG and coiled coil protein Alp7 in microtubule localization and bipolar spindle formation.

PubMed

Sato, Masamitsu; Vardy, Leah; Angel Garcia, Miguel; Koonrugsa, Nirada; Toda, Takashi

2004-04-01

The Dis1/TOG family plays a pivotal role in microtubule organization. In fission yeast, Alp14 and Dis1 share an essential function in bipolar spindle formation. Here, we characterize Alp7, a novel coiled-coil protein that is required for organization of bipolar spindles. Both Alp7 and Alp14 colocalize to the spindle pole body (SPB) and mitotic spindles. Alp14 localization to these sites is fully dependent upon Alp7. Conversely, in the absence of Alp14, Alp7 localizes to the SPBs, but not mitotic spindles. Alp7 forms a complex with Alp14, where the C-terminal region of Alp14 interacts with the coiled-coil domain of Alp7. Intriguingly, this Alp14 C terminus is necessary and sufficient for mitotic spindle localization. Overproduction of either full-length or coiled-coil region of Alp7 results in abnormal V-shaped spindles and stabilization of interphase microtubules, which is induced independent of Alp14. Alp7 may be a functional homologue of animal TACC. Our results shed light on an interdependent relationship between Alp14/TOG and Alp7. We propose a two-step model that accounts for the recruitment of Alp7 and Alp14 to the SPB and microtubules.

The Ortles ice cores: uncovering an extended climate archive from the Eastern Alps

NASA Astrophysics Data System (ADS)

Dreossi, Giuliano; Barbante, Carlo; Bertò, Michele; Carturan, Luca; De Blasi, Fabrizio; Gabrieli, Jacopo; Gabrielli, Paolo; Seppi, Roberto; Spolaor, Andrea; Stenni, Barbara; Zanoner, Thomas

2017-04-01

During the last half century, oxygen and hydrogen stable isotope content of ice cores has been extensively used for air temperature reconstructions. The most suitable glaciers of the Alpine area, most exclusively in the Western Alps, have been utilized for ice coring for more than four decades. The paleoclimatic potential of the Eastern Alps is still largely unexploited and was scarcely utilized in the past mainly because of the lower elevation (compared to Western Alps) and hence the difficulty to find glaciers in cold conditions. The warming temperature trend appears to be particularly pronounced in the Alps, threatening the preservation of the glaciated areas and creating a sense of urgency in retrieving climatic archives before it is too late. In autumn 2011, four deep cores were drilled on Mt Ortles, South Tyrol, Italy, at 3859 m a.s.l. An extensive reconstructed temperature record for the Ortles summit, based on the surrounding meteorological station data, is available for the last 150 years, while an automatic weather station had been operating from 2011 to 2015 in proximity of the drilling site. The new ice core chronology, based on 210Pb, tritium, beta emissions analysis and 14C measurements of the particulate organic carbon, indicates that the bottom ice is 7000 years old, making it the second most extended glaciological archive ever retrieved in the Alps. The three equally long ice cores have been analyzed for oxygen and hydrogen stable isotopes throughout their length, and the goal is to create an Ortles stacked record for d18O and dD and compare the isotopic data to instrumental temperatures and to other Alpine records. Since 2008, several snow pits were dug in proximity of the drilling site during summer, when the temperature can often exceed the melting point. The isotopic profiles of the 2015 snow pit, dug at the end of an exceptionally warm summer, show how the isotope signal is now affected by the post-depositional processes that have occurred

Pseudo- and real-inverted metamorphism caused by the superposition and extrusion of a stack of nappes: a case study of the Southern Brasília Orogen, Brazil

NASA Astrophysics Data System (ADS)

da Motta, Rafael Gonçalves; Moraes, Renato

2017-10-01

The Southern Brasília Orogen is a Neoproterozoic belt that occurs along the southernmost border of the São Francisco Craton where the Andrelândia Nappe System represents the subducted sedimentary domain and is divided into three allochthonous groups, of which the ages and P-T conditions of metamorphism are studied here. The basal unit, the Andrelândia Nappe, exhibits an inverted metamorphic pattern. The base of the structure, composed of staurolite, garnet, biotite, kyanite, quartz, and muscovite, marks the metamorphic peak, whereas at the top, the association of the metamorphic peak does not contain staurolite. The Liberdade Nappe, the middle unit, presents a normal metamorphic pattern; its base, close to the Andrelândia Nappe, shows paragneiss with evidence of in situ partial melting, and towards the top, coarse-grained staurolite schist is found. The staurolite-out and melt-in isograds are coincident and parallel to the main foliation. Thus, the shear zone that limits the nappes is syn-metamorphic, reheating the underlying Andrelândia Nappe and influencing the establishment of metamorphic inversion. This suggestion is supported by the monazite chemical ages, which indicates that the Andrelândia Nappe metamorphic peak (586 ± 15 Ma) is younger than that of the Liberdade Nappe (622.3 ± 7.6 Ma). The upper unit, the Serra da Natureza Klippe, bears a typical high-pressure granulite mineral assemblage that is composed of kyanite, garnet, K-feldspar, rutile, and leucosome, as well as a metamorphic peak at 604.5 ± 6.1 Ma. This tectonic assembly, with inverted and non-inverted metamorphic patterns and generation of klippen structures, is consistent with exhumation models and a strong indentor located in the lower continental crust.

Interdependency of Fission Yeast Alp14/TOG and Coiled Coil Protein Alp7 in Microtubule Localization and Bipolar Spindle FormationD⃞

PubMed Central

Sato, Masamitsu; Vardy, Leah; Angel Garcia, Miguel; Koonrugsa, Nirada; Toda, Takashi

2004-01-01

The Dis1/TOG family plays a pivotal role in microtubule organization. In fission yeast, Alp14 and Dis1 share an essential function in bipolar spindle formation. Here, we characterize Alp7, a novel coiled-coil protein that is required for organization of bipolar spindles. Both Alp7 and Alp14 colocalize to the spindle pole body (SPB) and mitotic spindles. Alp14 localization to these sites is fully dependent upon Alp7. Conversely, in the absence of Alp14, Alp7 localizes to the SPBs, but not mitotic spindles. Alp7 forms a complex with Alp14, where the C-terminal region of Alp14 interacts with the coiled-coil domain of Alp7. Intriguingly, this Alp14 C terminus is necessary and sufficient for mitotic spindle localization. Overproduction of either full-length or coiled-coil region of Alp7 results in abnormal V-shaped spindles and stabilization of interphase microtubules, which is induced independent of Alp14. Alp7 may be a functional homologue of animal TACC. Our results shed light on an interdependent relationship between Alp14/TOG and Alp7. We propose a two-step model that accounts for the recruitment of Alp7 and Alp14 to the SPB and microtubules. PMID:14742702

ALPS - A LINEAR PROGRAM SOLVER

NASA Technical Reports Server (NTRS)

Viterna, L. A.

1994-01-01

Linear programming is a widely-used engineering and management tool. Scheduling, resource allocation, and production planning are all well-known applications of linear programs (LP's). Most LP's are too large to be solved by hand, so over the decades many computer codes for solving LP's have been developed. ALPS, A Linear Program Solver, is a full-featured LP analysis program. ALPS can solve plain linear programs as well as more complicated mixed integer and pure integer programs. ALPS also contains an efficient solution technique for pure binary (0-1 integer) programs. One of the many weaknesses of LP solvers is the lack of interaction with the user. ALPS is a menu-driven program with no special commands or keywords to learn. In addition, ALPS contains a full-screen editor to enter and maintain the LP formulation. These formulations can be written to and read from plain ASCII files for portability. For those less experienced in LP formulation, ALPS contains a problem "parser" which checks the formulation for errors. ALPS creates fully formatted, readable reports that can be sent to a printer or output file. ALPS is written entirely in IBM's APL2/PC product, Version 1.01. The APL2 workspace containing all the ALPS code can be run on any APL2/PC system (AT or 386). On a 32-bit system, this configuration can take advantage of all extended memory. The user can also examine and modify the ALPS code. The APL2 workspace has also been "packed" to be run on any DOS system (without APL2) as a stand-alone "EXE" file, but has limited memory capacity on a 640K system. A numeric coprocessor (80X87) is optional but recommended. The standard distribution medium for ALPS is a 5.25 inch 360K MS-DOS format diskette. IBM, IBM PC and IBM APL2 are registered trademarks of International Business Machines Corporation. MS-DOS is a registered trademark of Microsoft Corporation.

Younger Dryas equilibrium line altitudes and precipitation patterns in the Alps

NASA Astrophysics Data System (ADS)

Kerschner, Hanns; Moran, Andrew; Ivy-Ochs, Susan

2016-04-01

Moraine systems of the "Egesen Stadial" are widespread and easily identifiable features in the Alps. Absolute dating with terrestrial cosmogenic radionuclides shows that the maximum extent was reached during the early Younger Dryas (YD), probably as a reaction to the intense climatic downturn subsequent to Lateglacial Interstadial. In recent years, several new studies and the availability of high-quality laser-scan hillshades and orthophotos allowed a significant extension of the database of YD glaciers as "palaeoprecipitation gauges" to large hitherto unmapped regions in the Austrian and Swiss Alps. The equilibrium line altitude (ELA) of the glaciers and its lowering relative to the Little Ice Age ELA (dELA) shows a distinct and systematic spatial pattern. Along the northern slope of the Alps, dELAs are usually large (around 400 m and perhaps even more), while dELAs range around 200 m in the well sheltered areas of the central Alps, e.g. in the Engadine and in western Tyrol. Both stochastic glacier-climate models (e.g. Ohmura et al. 1992) and the heat- and mass balance equation (Kuhn 1981) allow the reconstruction of precipitation change under the assumption of a spatially constant summer temperature depression, which in turn can be estimated from biological proxies. This allows to draw the spatial pattern of precipitation change with considerable detail. Precipitation change is clearly controlled by the local relief like high mountain chains, deeply incised and long valleys and mountain passes. Generally the contrast between the northern fringe of the Alps and the interior was more pronounced than today. Climate in the Northern and and Northwestern Alps was rather wet with precipitation totals eventually exceeding modern annual sums. The central Alps received 20 - 30% less precipitation than today, mainly due to reduced winter precipitation. In the southern Alps, still scarce spatial information points to precipitation sums which were approximately similar to

Reconstructing the Alps-Carpathians-Dinarides as a key to understanding switches in subduction polarity, slab gaps and surface motion

NASA Astrophysics Data System (ADS)

Handy, Mark R.; Ustaszewski, Kamil; Kissling, Eduard

2015-01-01

Palinspastic map reconstructions and plate motion studies reveal that switches in subduction polarity and the opening of slab gaps beneath the Alps and Dinarides were triggered by slab tearing and involved widespread intracrustal and crust-mantle decoupling during Adria-Europe collision. In particular, the switch from south-directed European subduction to north-directed "wrong-way" Adriatic subduction beneath the Eastern Alps was preconditioned by two slab-tearing events that were continuous in Cenozoic time: (1) late Eocene to early Oligocene rupturing of the oppositely dipping European and Adriatic slabs; these ruptures nucleated along a trench-trench transfer fault connecting the Alps and Dinarides; (2) Oligocene to Miocene steepening and tearing of the remaining European slab under the Eastern Alps and western Carpathians, while subduction of European lithosphere continued beneath the Western and Central Alps. Following the first event, post-late Eocene NW motion of the Adriatic Plate with respect to Europe opened a gap along the Alps-Dinarides transfer fault which was filled with upwelling asthenosphere. The resulting thermal erosion of the lithosphere led to the present slab gap beneath the northern Dinarides. This upwelling also weakened the upper plate of the easternmost part of the Alpine orogen and induced widespread crust-mantle decoupling, thus facilitating Pannonian extension and roll-back subduction of the Carpathian oceanic embayment. The second slab-tearing event triggered uplift and peneplainization in the Eastern Alps while opening a second slab gap, still present between the Eastern and Central Alps, that was partly filled by northward counterclockwise subduction of previously unsubducted Adriatic continental lithosphere. In Miocene time, Adriatic subduction thus jumped westward from the Dinarides into the heart of the Alpine orogen, where northward indentation and wedging of Adriatic crust led to rapid exhumation and orogen-parallel escape of

Pleistocene permafrost features in soils in the South-western Italian Alps

NASA Astrophysics Data System (ADS)

D'Amico, Michele; Catoni, Marcella; Bonifacio, Eleonora; Zanini, Ermanno

2015-04-01

Because of extensive Pleistocenic glaciations which erased most of the previously existing soils, slope steepness and climatic conditions favoring soil erosion, most soils observed on the Alps (and in other mid-latitude mountain ranges) developed only during the Holocene. However, in few sites, particularly in the outermost sections of the Alpine range, Pleistocene glaciers covered only small and scattered surfaces because of the low altitude reached in the basins, and ancient soils could be preserved for long periods of time on particularly stable surfaces. In some cases, these soils retain good memories of past periglacial activity. We described and sampled soils on stable surfaces in the Upper Tanaro valley, Ligurian Alps (Southwestern Piemonte, Italy). The sampling sites were between 600 to 1600 m of altitude, under present day lower montane Castanea sativa/Ostrya carpinifolia forests, montane Fagus sylvatica and Pinus uncinata forests or montane heath/grazed grassland, on different quartzitic substrata. The surface morphology often showed strongly developed, fossil periglacial patterned ground forms, such as coarse stone circles on flat surfaces, or stone stripes on steeper slopes. The stone circles could be up to 5 m wide, while the sorted stripes could be as wide as 12-15 m. A strong lateral cryogenic textural sorting characterized the fine fraction too, with sand dominating close to the stone rims of the patterned ground features and silt and clay the central parts. The surface 60-120 cm of the soils were podzolized during the Holocene; as a result of the textural lateral sorting, the thickness of the podzolic E and Bs horizons varied widely across the patterns. The lower boundary of the Holocene Podzols was abrupt, and corresponded with dense layers with thick coarse laminar structure and illuvial silt accumulation (Cjj horizons). Dense Cjj diapiric inclusions were sometimes preserved in the central parts of the patterns. Where cover beds were developed

A transect through the base of the Bronson Hill Terrane in western New Hampshire

USGS Publications Warehouse

Walsh, Gregory J.; Valley, Peter M.; Sicard, Karri R.; Thompson, Thelma Barton; Thompson, Peter J.

2012-01-01

This trip will present the preliminary results of ongoing bedrock mapping in the North Hartland and Claremont North 7.5-minute quadrangles in western New Hampshire. The trip will travel from the Lebanon pluton to just north of the Sugar River pluton (Fig. 1) with the aim of examining the lower structural levels of the Bronson Hill anticlinorium (BHA), and the nature of the boundary with the rocks of the Connecticut Valley trough (CVT). Spear and others (2002, 2003, 2008) proposed that western New Hampshire was characterized by five major faults bounding five structural levels including, from lowest to highest, the “chicken yard line”, Western New Hampshire Boundary Thrust, Skitchewaug nappe, Fall Mountain nappe, and Chesham Pond nappe. Lyons and others (1996, 1997) showed the lowest level cored by the Cornish nappe and floored by the Monroe fault. Thompson and others (1968) explained the geometry of units by folding without major thrust faults, and described the second level as the Skitchewaug nappe. This trip will focus on the two lowest levels which we have revised to call the Monroe and Skitchewaug Mountain thrust sheets. Despite decades of geologic mapping in the northeastern United States at various scales, little 1:24,000-scale (or larger scale) modern bedrock mapping has been published for the state of New Hampshire. In fact, of the New England states, New Hampshire contains the fewest published, modern bedrock geologic maps. Conversely, adjacent Vermont has a relatively high percentage of modern bedrock maps due to focused efforts to create a new state-wide bedrock geologic map over the last few decades. The new Vermont map (Ratcliffe and others, 2011) has identified considerable gaps in our knowledge of the bedrock geology in adjacent New Hampshire where published maps are, in places, more than 50 years old and at scales ranging from 1:62,500 to 1:250,000. Fundamental questions remain concerning the geology across the Connecticut River, especially in

Hydrocarbon potential of the Early Oligocene Menilite shales in the Eastern Outer Carpathians (Tarcău and Vrancea Nappes, Romania)

NASA Astrophysics Data System (ADS)

Wendorff, Małgorzata; Rospondek, Mariusz; Kluska, Bartosz; Marynowski, Leszek

2017-04-01

During Oligocene to early Miocene time an extensive accumulation of organic-rich sedimentary rocks occurred in entire Paratethyan Basin, including its central part, i.e. the Carpathian Foredeep basin. Rocks of so-called Menilite facies formed there, burying significant amounts of organic matter (OM). These Menilite shales are now widely considered as a source of hydrocarbons throughout the Carpathian region. For the purpose of presented study, rock samples of the Menilite facies (mainly of the Lower Menilite and Bituminous Marl Members) were collected from two sections located in the different tectonic units (the Tarcău and Vrancea Nappes, Romania) of the Outer Carpathians. The main goal of the study was to assess and compare their hydrocarbon potential by examination of bulk geochemistry (total organic carbon content, pyrolysis Rock-Eval), vitrinite reflectance (Ro) and application of lipid biomarker parameters. The data show high variability in OM quantity and quality. Total organic carbon (TOC) content reaches peak values in the siliceous facies of the Lower Menilite Member (up to 8.6 wt% TOC), which contains type II kerogen represented by mainly marine OM type. Such results are confirmed by the presence of short-chain n-alkanes and hopanes. Mixed type II/III kerogen gains importance together with increasing contribution of turbiditic sedimentation. Terrigenous input is marked by occurrence of conifer aromatic biomarkers (such as simonellite, retene and 1,2,3,4-tetrahydroretene) and odd over even long chain n-alkanes predominance, characteristic for epicuticular leaf waxes. The analysed source rocks can be classified as oil-prone and subordinately mixed oil/gas-prone. OM in the inner tectonic unit (Tarcău Nappe; Tmax 430° C, Ro 0.5%) reaches onset of hydrocarbon generation, while in the outer unit (Vrancea Nappe) OM is immature (Tmax 425° C, Ro 0.4%). This maturity trend may be an effect of different burial histories of these units, as well as variation in

ALPS: A Linear Program Solver

NASA Technical Reports Server (NTRS)

Ferencz, Donald C.; Viterna, Larry A.

1991-01-01

ALPS is a computer program which can be used to solve general linear program (optimization) problems. ALPS was designed for those who have minimal linear programming (LP) knowledge and features a menu-driven scheme to guide the user through the process of creating and solving LP formulations. Once created, the problems can be edited and stored in standard DOS ASCII files to provide portability to various word processors or even other linear programming packages. Unlike many math-oriented LP solvers, ALPS contains an LP parser that reads through the LP formulation and reports several types of errors to the user. ALPS provides a large amount of solution data which is often useful in problem solving. In addition to pure linear programs, ALPS can solve for integer, mixed integer, and binary type problems. Pure linear programs are solved with the revised simplex method. Integer or mixed integer programs are solved initially with the revised simplex, and the completed using the branch-and-bound technique. Binary programs are solved with the method of implicit enumeration. This manual describes how to use ALPS to create, edit, and solve linear programming problems. Instructions for installing ALPS on a PC compatible computer are included in the appendices along with a general introduction to linear programming. A programmers guide is also included for assistance in modifying and maintaining the program.

Sedimentary connection between rock glaciers and torrential channels: definition, inventory and quantification from a test area in the south-western Swiss Alps

NASA Astrophysics Data System (ADS)

Kummert, Mario; Barboux, Chloé; Delaloye, Reynald

2017-04-01

order to validate these estimations, the resulting sediment transfer rates are compared to transfer rates calculated from repeated terrestrial LiDAR surveys on selected study cases. This contribution presents results from the application of this methodology in a test study area in the south-western Swiss Alps. The methodology reveals itself suitable to identify rock glaciers connected to the torrential network. For each of the detected rock glaciers, an estimation of the sediment yield is proposed. The transfer rates range from tens of cubic meters per year for some slow moving and/or partially connected landforms, to several thousands of cubic meters per year. References: Delaloye R. (2004). Contribution à l'étude du pergélisol de montagne en zone marginale. GeoFocus vol. 10, Thèse, Département de Géosciences/Géographie, Université de Fribourg. Delaloye, R., Lambiel, C., Gärtner-Roer, I. (2010). Overview of rock glacier kinematics research in the Swiss Alps. Seasonal rhythm, interannual variations and trends over several decades. Geogr. Helv., 65: 2, 135-145. Delaloye, R., Morard, S., Barboux, C., Abbet, D., Gruber, V., Riedo, M. & Gachet, S. (2013). Rapidly moving rock glaciers in Mattertal. In: Graf, C. (Eds). Mattertal - ein Tal in Bewegung. Publikation zur Jahrestagung der Schweizerischen Geomorphologischen Gesellschaft 29. Juni - 1. Juli 2011, St. Niklaus, Birmensdorf, Eidg. Forschungsanstalt WSL, 113 - 124. Gärtner-Roer, I. (2012). Sediment transfer rates of two active rockglaciers in the Swiss Alps. Geomorphology, 167-168, 45-50. Lugon, R. & Stoffel, M. (2010). Rock glacier dynamics and magnitude-frequency relations of debris flows in a high-elevation watershed : Ritigraben, Swiss Alps. Global and Planetary Change, 73, 202-210.

Influence of Prescribed Herbal and Western Medicine on Patients with Abnormal Liver Function Tests: A Retrospective Quasi-Experimental Study

PubMed Central

Lee, Ah-Ram; Yim, Je-Min; Kim, Won-Il

2012-01-01

Objectives: The aim of this study was to investigate the safety and the efficacy of Korean herbal, western and combination medicine use in patients with abnormal liver function tests. Methods: We investigated nerve disease patients with abnormal liver function tests who were treated with Korean herbal, western and combination medicine at Dong-Eui University Oriental Hospital from January 2011 to August 2011. We compared aspartic aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP) and total bilirubin (T-bil) levels before and after taking medicine and excluded patients who had liver-related disease when admitted. Results: AST and ALT were decreased significantly in patients who had taken herbal, western medicine. AST, ALT and ALP were decreased significantly in patients who had taken combination medicine. Compare to herbal medicine, AST, ALT and ALP were decreased significantly in patients who had taken western medicine, and ALT and ALP were decreased significantly in patients who had taken combination medicine. There were no significant differences between western and combination medicine. Conclusions: This study suggests that prescribed Korean herbal medicine, at least, does not injure liver function for patients’, moreover, it was shown to be effective in patients with abnormal liver function tests. PMID:25780634

Pre-Alpine evolution of the Seckau Complex (Austroalpine basement/Eastern Alps): Constraints from in-situ LA-ICP-MS Usbnd Pb zircon geochronology

NASA Astrophysics Data System (ADS)

Mandl, Magdalena; Kurz, Walter; Hauzenberger, Christoph; Fritz, Harald; Klötzli, Urs; Schuster, Ralf

2018-01-01

The Variscan European Belt is a complex orogen with its southern margin partly obscured by Alpine tectonics and metamorphism. We present a study of one of the units, the Seckau Complex, that constitute the southern part of the Variscan European Belt in the Eastern Alps in order to clarify its origin, age and lithostratigraphy. The magmatic and geochronological evolution of this Complex in the northwestern part of the Seckau Nappe (as part of the Austroalpine Silvretta-Seckau Nappe System) was investigated by zircon Usbnd Pb dating of paragneisses and metagranitoids coupled with petrological and geochemical data. This reveals the distinction of three newly defined lithostratigraphic/lithodemic sub-units: (1) Glaneck Metamorphic Suite, (2) Hochreichart Plutonic Suite and (3) Hintertal Plutonic Suite. The Glaneck Metamorphic Suite is mainly composed of fine-grained paragneisses that yield Usbnd Pb zircon ages in the range between 2.7 Ga and 2.0 Ga, as well as concordia ages from 572 ± 7 Ma to 559 ± 11 Ma. All of these ages are interpreted as detrital zircon ages originating from an igneous source. The paragneisses are the host rock for the large volumes of metagranitoids of the Hochreichart Plutonic Suite and the Hintertal Plutonic Suite. The Hochreichart Plutonic Suite comprises highly fractionated melts with mainly S-type characteristics and late Cambrian to Early Ordovician Usbnd Pb zircon ages (508 ± 9 Ma to 486 ± 9 Ma), interpreted as magmatic protolith ages. The Hintertal Plutonic Suite is composed of metagranitoids with Late Devonian to early Carboniferous (365 ± 11 Ma and 331 ± 10 Ma) protolith ages, that intruded during an early phase of the Variscan tectonometamorphic event. The metagranitoids of the Hintertal Plutonic Suites define a magmatic fractionation trend, seen in variable Rb/Sr ratios. On this base they can be further subdivided into (a) the Griessstein Pluton characterized by S-type metagranitoids and (b) the Pletzen Pluton distinguished by

Quantifying the Eocene to Pleistocene topographic evolution of the southwestern Alps, France and Italy

NASA Astrophysics Data System (ADS)

Fauquette, Séverine; Bernet, Matthias; Suc, Jean-Pierre; Grosjean, Anne-Sabine; Guillot, Stéphane; van der Beek, Peter; Jourdan, Sébastien; Popescu, Speranta-Maria; Jiménez-Moreno, Gonzalo; Bertini, Adele; Pittet, Bernard; Tricart, Pierre; Dumont, Thierry; Schwartz, Stéphane; Zheng, Zhuo; Roche, Emile; Pavia, Giulio; Gardien, Véronique

2015-02-01

We evaluate the topographic evolution of the southwestern Alps using Eocene to Pleistocene pollen data combined with existing sedimentological, petrographic and detrital geo- and thermochronological data. We report 32 new pollen analyses from 10 sites completed by an existing dataset of 83 samples from 14 localities situated across the southwestern Alps, including both the pro- and the retro-foreland basins. The presence of microthermic tree pollen (mainly Abies, Picea) indicates that this part of the mountain belt attained elevations over 1900 m as early as the Oligocene. Inferred rapid surface uplift during the mid-Oligocene coincided with a previously documented brief phase of rapid erosional exhumation, when maximum erosion rates may have reached values of up to 1.5-2 km/Myr. Slower long-term average exhumation rates of ∼0.3 km/Myr since the Late Oligocene helped maintaining the high Alpine topography of the southwestern Alps until today. The relative abundances of meso-microthermic tree pollen (Cathaya, Cedrus and Tsuga) and microthermic tree pollen (Abies, Picea) in the pro- and retro-foreland basin deposits, indicate that the present-day asymmetric topography, with a relatively gentle western flank and steeper eastern flank, was established early in the southwestern Alps, at least since the Early Miocene, and possibly since the Oligocene or Late Eocene. Therefore, the high topography and asymmetric morphology of this part of the Alps has been maintained throughout the past ∼30 Ma.

Steady-State ALPS for Real-Valued Problems

NASA Technical Reports Server (NTRS)

Hornby, Gregory S.

2009-01-01

The two objectives of this paper are to describe a steady-state version of the Age-Layered Population Structure (ALPS) Evolutionary Algorithm (EA) and to compare it against other GAs on real-valued problems. Motivation for this work comes from our previous success in demonstrating that a generational version of ALPS greatly improves search performance on a Genetic Programming problem. In making steady-state ALPS some modifications were made to the method for calculating age and the method for moving individuals up layers. To demonstrate that ALPS works well on real-valued problems we compare it against CMA-ES and Differential Evolution (DE) on five challenging, real-valued functions and on one real-world problem. While CMA-ES and DE outperform ALPS on the two unimodal test functions, ALPS is much better on the three multimodal test problems and on the real-world problem. Further examination shows that, unlike the other GAs, ALPS maintains a genotypically diverse population throughout the entire search process. These findings strongly suggest that the ALPS paradigm is better able to avoid premature convergence then the other GAs.

New Zealand's Southern Alps

NASA Technical Reports Server (NTRS)

2001-01-01

The rugged Southern Alps extend some 650 kilometers along the western side of New Zealand's South Island. The mountains are often obscured by clouds, which is probably why the Maoris called New Zealand 'Aotearoa', the long white cloud. The higher peaks are snow-covered all year round. Westerly winds bring clouds that drop over 500 centimeters of rain annually on luxuriant rain forest along the west coast. The drier eastern seaboard is home to the majority of the island's population.

This pair of MISR images is from April 13, 2000 (Terra orbit 1712). The upper image is a natural color view from the instrument's vertical-viewing (nadir) camera. It is presented at a resolution of 550 meters per pixel. The lower image is a stereo anaglyph generated from the instrument's 46-degree and 26-degree forward-viewing cameras, and is presented at 275-meter per pixel resolution to show the portion of the image containing the Southern Alps in greater detail. Viewing the anaglyph in 3-D requires the use of red/blue glasses with the red filter over your left eye. To facilitate stereoscopic viewing, both images have been oriented with north at the left.

The tallest mountain in the Southern Alps is Mt. Cook, at an elevation of 3754 meters. Its snow-covered peak is visible to the left of center in each of these MISR images. From the high peaks, glaciers have gouged long, slender mountain lakes and coastal fiords. Immediately to the southeast of Mt. Cook (to the right in these images), the glacial pale-blue water of Lake Pukaki stands out. Further to the south in adjacent valleys you can easily see Lakes Hawea and Wanaka, between which (though not visible here) is the Haast Pass Road, the most southerly of the few links between the east and west coast road systems. Further to the south is the prominent 'S' shape of Lake Wakatipu, 83 kilometers long, on the northern shore of which is Queenstown, the principal resort town of the island. The remote and spectacular Fiordland National

13 CFR 120.840 - Accredited Lenders Program (ALP).

Code of Federal Regulations, 2011 CFR

2011-01-01

... (ALP). (a) General. Under the ALP program, SBA designates qualified CDCs as ALP CDCs, gives them... approval and servicing actions. (b) Application. A CDC must apply for ALP status to the Lead SBA Office.... (c) Eligibility. In order for a CDC to be eligible to receive ALP status, its application must show...

13 CFR 120.840 - Accredited Lenders Program (ALP).

Code of Federal Regulations, 2014 CFR

2014-01-01

... (ALP). (a) General. Under the ALP program, SBA designates qualified CDCs as ALP CDCs, gives them... approval and servicing actions. (b) Application. A CDC must apply for ALP status to the Lead SBA Office.... (c) Eligibility. In order for a CDC to be eligible to receive ALP status, its application must show...

13 CFR 120.840 - Accredited Lenders Program (ALP).

Code of Federal Regulations, 2012 CFR

2012-01-01

... (ALP). (a) General. Under the ALP program, SBA designates qualified CDCs as ALP CDCs, gives them... approval and servicing actions. (b) Application. A CDC must apply for ALP status to the Lead SBA Office.... (c) Eligibility. In order for a CDC to be eligible to receive ALP status, its application must show...

13 CFR 120.840 - Accredited Lenders Program (ALP).

Code of Federal Regulations, 2010 CFR

2010-01-01

... (ALP). (a) General. Under the ALP program, SBA designates qualified CDCs as ALP CDCs, gives them... approval and servicing actions. (b) Application. A CDC must apply for ALP status to the Lead SBA Office.... (c) Eligibility. In order for a CDC to be eligible to receive ALP status, its application must show...

13 CFR 120.840 - Accredited Lenders Program (ALP).

Code of Federal Regulations, 2013 CFR

2013-01-01

... (ALP). (a) General. Under the ALP program, SBA designates qualified CDCs as ALP CDCs, gives them... approval and servicing actions. (b) Application. A CDC must apply for ALP status to the Lead SBA Office.... (c) Eligibility. In order for a CDC to be eligible to receive ALP status, its application must show...

Hot Alps (Invited)

NASA Astrophysics Data System (ADS)

Speranza, F.; Minelli, L.; Pignatelli, A.; Gilardi, M.

2013-12-01

Although it is frequently assumed that crust of Alpine orogens is hot due to the occurrence of thick and young (hence radiogenic) crust, evidence on the thermal ranking of orogens is contradictory. Heat flow measurements from shallow wells (depth ≤ 1 km) in the Alps yield a relatively cold thermal regime of 50-80 mW/m2, but data are likely biased by meteoric cold-water circulation. Here we report on the spectral analysis of the aeromagnetic residuals of northern Italy to derive the Curie point depth (CPD), assumed to represent the 600°C isotherm depth. Airborne magnetics were acquired on whole Italy during the 1970s by the national oil company AGIP (now Eni). Data were gathered by several surveys carried out at 1000-13,300 feet (300-4000 m) altitude, with flight line spacing of 2-10 km. Surveys of the Alps and Po Plain (northern Italy) were obtained both with a line spacing of 5 km (and 5 km tie lines), at an altitude of 4000-5000 and 13,300 feet, respectively. To evaluate CPDs we used the centroid method (routinely adopted in recent CPD studies on East Asia and central-southern Europe) on 72 square windows of 100-110 km edge, with a 50% degree of superposition. CPDs vary between 16 and 38 km (22 km on average) in the Po Plain, located south of the Alps and representing the Adriatic-African foreland area. Conversely, the Alps yield very shallow CPDs, ranging between 6 and 15 km (10 km on average). CPDs fall systematically above local Moho depths, implying that magnetic source bottoms documented in this study do not represent a lithological boundary over non-magnetic peridotitic mantle, but can be safely associated with CPDs and the 600°C isotherm. CPDs from the Po Plain are in rough agreement with reported heat flow values of 25-60 mW/m2, and imply and average thermal conductivity (k) of the Po Plain crust of 1.5 W/m°K, at the lower bound of k values measured and inferred for the crust. Conversely, the average 10 km CPD documented in the Alps translates into

Orogen-scale anticline revealed in the Southern Alps of New Zealand by structural thermochronology

NASA Astrophysics Data System (ADS)

Zhou, Renjie; Brandon, Mark

2017-04-01

A dense set of cooling ages from the Southern Alps reveals an orogen-scale anticline of cooling-age isosurfaces (isochrones) and provides an interesting example of structural thermochronology, where isochrones are used as structural markers. The isochrone concept is an integral aspect of the age-elevation method, but the latter implicitly assumes that all isochrones are horizontal. Our experience in New Zeland and elsewhere is that isochrones are commonly tilted after formation. We use a more general approach that solves for orientation of the isochrone surfaces, and also the slope of the age-elevation trend, where "elevation" is measured normal to the isochrone surfaces. In New Zealand, collision and convergence between the Pacific and Australian plates have resulted in the formation and continuing growth of the Southern Alps, a prototypical orogenic wedge. In the western side, the Southern Alps is bounded by the Alpine fault, along with deeply exhumed rocks from depths up to 25 km. There are 150 apatite and 200 zircon fission-track (AFT, ZFT) ages that cover the vast region of the South Island of New Zealand from Lake Summer to Lake Wanaka. The AFT ages range from <0.5 to 140 Ma, and the ZFT ages, from <0.5 to 400 Ma. Our approach was initiated by McPhillips and Brandon (Earth and Planetary Science Letters, 2010, doi: 10.1016/j.epsl.2010.05.022). We use a least-squares method to solve for a best-fit sequence of dipping isochrone surfaces. The solution specifies the strike, dip and spacing of the parallel isochrones, the last of which indicates the velocity of the isochrones passing through the closure depth. We find that the calculation of the entire dataset failed to yield reasonable results, implying nonplanar structures at the regional scale. Using subsets of data, we observed three distinct zones of isochrones from E to W across the South Island. 1) The large area east of the Southern Alps in the central South Island contains ZFT isochrones that dip shallowly

Effects of large deep-seated landslides on hillslope morphology, western Southern Alps, New Zealand

NASA Astrophysics Data System (ADS)

Korup, Oliver

2006-03-01

Morphometric analysis and air photo interpretation highlight geomorphic imprints of large landslides (i.e., affecting ≥1 km2) on hillslopes in the western Southern Alps (WSA), New Zealand. Large landslides attain kilometer-scale runout, affect >50% of total basin relief, and in 70% are slope clearing, and thus relief limiting. Landslide terrain shows lower mean local relief, relief variability, slope angles, steepness, and concavity than surrounding terrain. Measuring mean slope angle smoothes out local landslide morphology, masking any relationship between large landslides and possible threshold hillslopes. Large failures also occurred on low-gradient slopes, indicating persistent low-frequency/high-magnitude hillslope adjustment independent of fluvial bedrock incision. At the basin and hillslope scale, slope-area plots partly constrain the effects of landslides on geomorphic process regimes. Landslide imprints gradually blend with relief characteristics at orogen scale (102 km), while being sensitive to length scales of slope failure, topography, sampling, and digital elevation model resolution. This limits means of automated detection, and underlines the importance of local morphologic contrasts for detecting large landslides in the WSA. Landslide controls on low-order drainage include divide lowering and shifting, formation of headwater basins and hanging valleys, and stream piracy. Volumes typically mobilized, yet still stored in numerous deposits despite high denudation rates, are >107 m3, and theoretically equal to 102 years of basin-wide debris production from historic shallow landslides; lack of absolute ages precludes further estimates. Deposit size and mature forest cover indicate residence times of 101-104 years. On these timescales, large landslides require further attention in landscape evolution models of tectonically active orogens.

Fission track ages and Exhumation mechanisms of the Tauern Window, Eastern Alps

NASA Astrophysics Data System (ADS)

Bertrand, Audrey; Rosenberg, Claudio; Garcia, Sebastian

2010-05-01

The Tauern Window (TW) is a thermal and structural dome which exposes Penninic basement, its cover units as well as parts of the overlying Austroalpine basement in the central part of the Eastern Alps. The peak of metamorphism was attained approximately at 30Ma (Selverstone et .al, 1992), followed by cooling and exhumation throughout Miocene time. Most of the tertiary exhumation of the Eastern Alps was localized in the TW, from Early Oligocene to late Miocene time. A current debate centers on the exhumation mechanisms of Penninic rocks in the core of the TW, namely to assess whether orogen-parallel extension (e.g., Selverstone, 1988) or a combination of folding and erosion (eg., Rosenberg et al., 2004) with subordinate extension were the controlling processes. E-W extension is well documented at the western (Brenner Fault) and eastern (Katschberg Fault) margins of the window (e.g., Behrmann, 1988; Selverstone, 1988; Genser and Neubauer, 1989). In contrast, upright folding dominates the internal structure of the dome, and in particular along its western part, where fold amplitudes, mostly eroded during folding, attained up to 10 km. This study attempts to assess the relative importance of folding and erosion and of orogen-parallel extension during exhumation by analyzing the spatial and temporal cooling patterns of apatite and zircon fission track ages. The compilation of published apatite and zircon fission track ages indicates a concentric younging of both the apatite and zircon ages toward the core of the TW. The concentric isochrones follow the map trace of the axial planes of the upright folds of the western and eastern TW. This cooling pattern is in contrast to the one expected by a process of extensional unroofing, which in map view would results in isochrons parallel to the extensional faults and progressively younging towards them (e.g., Foster et al., 2001). We therefore propose that folding and erosion were primarily responsible for exhuming the Penninic

Discovery of a landscape-wide drape of late-glacial aeolian silt in the western Northern Calcareous Alps (Austria): First results and implications

NASA Astrophysics Data System (ADS)

Gild, Charlotte; Geitner, Clemens; Sanders, Diethard

2018-01-01

Aeolian deposits record palaeoenvironmental conditions and may coin soil properties. Whereas periglacial loess is extensively investigated for 200 years, the study of the intramontane wind-blown deposits of the Alps has just stuttered along. Herein, we describe a drape of polymictic siliciclastic silt interpreted as an aeolian deposit that veneers extensive areas in the western Northern Calcareous Alps (NCA), from kames terraces near valley floors up to last-glacial nunataks. The NCA - part of the Eastern Alps mountain range - consist mainly of Triassic carbonate rocks; these are overlain by deposits of the Last Glacial Maximum (LGM) and its deglacial-paraglacial aftermath (e.g., glacial tills, fluvio-lacustrine successions, alluvial fans, scree slopes) - and a regional drape of polymictic silt newly described herein. The drape is typically a few decimeters in thickness and slightly modified by soil formation; it consists mainly of well-sorted silt of quartz, feldspars, phyllosilicates (muscovite, chlorite, biotite), amphiboles and, rarely, calcite or dolomite. The drape is unrelated to the substrate: it overlies carbonate bedrock and - in lateral continuity - abandoned deposystems such as colluvial slopes of redeposited till, kames, alluvial fans, scree slopes, and rock avalanche deposits. The drape was spotted from near the present valley floors up to LGM nunataks, over a vertical range of some 2000 m; it is also present in catchments of the NCA that were not overridden by far-travelled ice streams and that lack metamorphic rock fragments. Two OSL quartz ages of the drape from two distinct locations (18.77 ± 1.55 ka; 17.81 ± 1.68 ka) fall into the early Alpine late-glacial interval shortly after the collapse of pleniglacial ice streams; this fits with geological and geomorphological evidence, respectively, that the drape should be of early late-glacial age, and that it accumulated during a specific interval of time. In the NCA, localized minor deposition of

Climate Change and Human Disturbance Can Lead to Local Extinction of Alpine Rock Ptarmigan: New Insight from the Western Italian Alps

PubMed Central

Imperio, Simona; Bionda, Radames; Viterbi, Ramona; Provenzale, Antonello

2013-01-01

Alpine grouses are particularly vulnerable to climate change due to their adaptation to extreme conditions and to their relict distributions in the Alps where global warming has been particularly marked in the last half century. Grouses are also currently threatened by habitat modification and human disturbance, and an assessment of the impact of multiple stressors is needed to predict the fate of Alpine populations of these birds in the next decades. We estimated the effect of climate change and human disturbance on a rock ptarmigan population living in the western Italian Alps by combining an empirical population modelling approach and stochastic simulations of the population dynamics under the a1B climate scenario and two different disturbance scenarios, represented by the development of a ski resort, through 2050.The early appearance of snow-free ground in the previous spring had a favorable effect on the rock ptarmigan population, probably through a higher reproductive success. On the contrary, delayed snowfall in autumn had a negative effect possibly due to a mismatch in time to molt to white winter plumage which increases predation risk. The regional climate model PROTHEUS does not foresee any significant change in snowmelt date in the study area, while the start date of continuous snow cover is expected to be significantly delayed. The net effect in the stochastic projections is a more or less pronounced (depending on the model used) decline in the studied population. The addition of extra-mortality due to collision with ski-lift wires led the population to fatal consequences in most projections. Should these results be confirmed by larger studies the conservation of Alpine populations would deserve more attention. To counterbalance the effects of climate change, the reduction of all causes of death should be pursued, through a strict preservation of the habitats in the present area of occurrence. PMID:24260581

Climate change and human disturbance can lead to local extinction of Alpine rock ptarmigan: new insight from the western Italian Alps.

PubMed

Imperio, Simona; Bionda, Radames; Viterbi, Ramona; Provenzale, Antonello

2013-01-01

Alpine grouses are particularly vulnerable to climate change due to their adaptation to extreme conditions and to their relict distributions in the Alps where global warming has been particularly marked in the last half century. Grouses are also currently threatened by habitat modification and human disturbance, and an assessment of the impact of multiple stressors is needed to predict the fate of Alpine populations of these birds in the next decades. We estimated the effect of climate change and human disturbance on a rock ptarmigan population living in the western Italian Alps by combining an empirical population modelling approach and stochastic simulations of the population dynamics under the a1B climate scenario and two different disturbance scenarios, represented by the development of a ski resort, through 2050.The early appearance of snow-free ground in the previous spring had a favorable effect on the rock ptarmigan population, probably through a higher reproductive success. On the contrary, delayed snowfall in autumn had a negative effect possibly due to a mismatch in time to molt to white winter plumage which increases predation risk. The regional climate model PROTHEUS does not foresee any significant change in snowmelt date in the study area, while the start date of continuous snow cover is expected to be significantly delayed. The net effect in the stochastic projections is a more or less pronounced (depending on the model used) decline in the studied population. The addition of extra-mortality due to collision with ski-lift wires led the population to fatal consequences in most projections. Should these results be confirmed by larger studies the conservation of Alpine populations would deserve more attention. To counterbalance the effects of climate change, the reduction of all causes of death should be pursued, through a strict preservation of the habitats in the present area of occurrence.

A low-temperature ductile shear zone: The gypsum-dominated western extension of the brittle Fella-Sava Fault, Southern Alps.

PubMed

Bartel, Esther Maria; Neubauer, Franz; Heberer, Bianca; Genser, Johann

2014-12-01

Based on structural and fabric analyses at variable scales we investigate the evaporitic gypsum-dominated Comeglians-Paularo shear zone in the Southern Alps (Friuli). It represents the lateral western termination of the brittle Fella-Sava Fault. Missing dehydration products of gypsum and the lack of annealing indicate temperatures below 100 °C during development of the shear zone. Despite of such low temperatures the shear zone clearly exhibits mylonitic flow, thus evidencing laterally coeval activity of brittle and viscous deformation. The dominant structures within the gypsum rocks of the Lower Bellerophon Formation are a steeply to gently S-dipping foliation, a subhorizontal stretching lineation and pure shear-dominated porphyroclast systems. A subordinate simple shear component with dextral displacement is indicated by scattered σ-clasts. Both meso- and microscale structures are characteristic of a subsimple shear type of deformation with components of both coaxial and non-coaxial strain. Shortening in a transpressive regime was accommodated by right-lateral displacement and internal pure shear deformation within the Comeglians-Paularo shear zone. The shear zone shows evidence for a combination of two stretching faults, where stretching occurred in the rheologically weaker gypsum member and brittle behavior in enveloping lithologies.

Mapping Asbestos-Cement Roofing with Hyperspectral Remote Sensing over a Large Mountain Region of the Italian Western Alps

PubMed Central

Frassy, Federico; Candiani, Gabriele; Rusmini, Marco; Maianti, Pieralberto; Marchesi, Andrea; Nodari, Francesco Rota; Via, Giorgio Dalla; Albonico, Carlo; Gianinetto, Marco

2014-01-01

The World Health Organization estimates that 100 thousand people in the world die every year from asbestos-related cancers and more than 300 thousand European citizens are expected to die from asbestos-related mesothelioma by 2030. Both the European and the Italian legislations have banned the manufacture, importation, processing and distribution in commerce of asbestos-containing products and have recommended action plans for the safe removal of asbestos from public and private buildings. This paper describes the quantitative mapping of asbestos-cement covers over a large mountainous region of Italian Western Alps using the Multispectral Infrared and Visible Imaging Spectrometer sensor. A very large data set made up of 61 airborne transect strips covering 3263 km2 were processed to support the identification of buildings with asbestos-cement roofing, promoted by the Valle d'Aosta Autonomous Region with the support of the Regional Environmental Protection Agency. Results showed an overall mapping accuracy of 80%, in terms of asbestos-cement surface detected. The influence of topography on the classification's accuracy suggested that even in high relief landscapes, the spatial resolution of data is the major source of errors and the smaller asbestos-cement covers were not detected or misclassified. PMID:25166502

Relationships between botanical and chemical composition of forages: a multivariate approach to grasslands in the Western Italian Alps.

PubMed

Ravetto Enri, Simone; Renna, Manuela; Probo, Massimiliano; Lussiana, Carola; Battaglini, Luca M; Lonati, Michele; Lombardi, Giampiero

2017-03-01

Plant composition of species-rich mountain grasslands can affect the sensorial and chemical attributes of dairy and meat products, with implications for human health. A multivariate approach was used to analyse the complex relationships between vegetation characteristics (botanical composition and plant community variables) and chemical composition (proximate constituents and fatty acid profile) in mesophilic and dry vegetation ecological groups, comprising six different semi-natural grassland types in the Western Italian Alps. Mesophilic and dry grasslands were comparable in terms of phenology, biodiversity indices and proportion of botanical families. The content of total fatty acids and that of the most abundant fatty acids (alpha-linolenic, linoleic and palmitic acids) were mainly associated to nutrient-rich plant species, belonging to the mesophilic grassland ecological group. Mesophilic grasslands showed also higher values of crude protein, lower values of fibre content and they were related to higher pastoral values of vegetation compared to dry grasslands. The proximate composition and fatty acid profile appeared mainly single species dependent rather than botanical family dependent. These findings highlight that forage from mesophilic grasslands can provide higher nutritive value for ruminants and may be associated to ruminant-derived food products with a healthier fatty acid profile. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Deformation of ``Villafranchian'' lacustrine sediments in the Chisone Valley (Western Alps, Italy)

NASA Astrophysics Data System (ADS)

Collo, Giovanni; Giardino, Marco

1997-09-01

The Chisone Valley is located in the internal NW Alps, in the Pinerolese District, an area characterized by present low to medium seismicity. Fine-grained sediments (sand, silt and clay with interbedded gravel) crop out in the lower Chisone Valley: they were first interpreted as glaciolacustrine deposits, and then as a lacustrine infilling of the valley floor probably due to differential uplifting of the valley mouth. Review of this data, together with new field and palynological observations, lead us to refer the lacustrine deposits to approximately the Lower Pleistocene (Villafranchian). In many outcrops, the lacustrine deposits show strong soft-sediment deformation such as convolute laminations, water-escape structures and disrupted beds, some of them associated with folds and faults (cm to dm in size); only two sites show metric to decametric folds and faults trending E-W and N-S. Detailed structural analysis conducted along a recently exposed section (Rio Gran Dubbione site) shows several soft-sediment deformation features on the limbs of mesoscale folds. Because of their intimate structural association, the origin of these minor structures seems to be connected to synsedimentary activity on reverse and normal faults (m to dm in size) affecting the lacustrine deposits in the same locality. Soft-sediment deformation features can be interpreted as possible paleoseismites. If so, the present seismicity of the Pinerolese District, which is the major area of such activity in NW Italy, cannot be considered an isolated episode in the geological evolution of the region; even if there is no supporting evidence for continuous seismicity, the deformations in the lacustrine sediments of the Chisone Valley testify to Early Pleistocene seismic activity, probably related to the recent tectonic evolution of the internal side of the NW Alps.

Re-evaluation of polyphase kinematic and 40Ar/39Ar cooling history of Moldanubian hot nappe at the eastern margin of the Bohemian Massif

NASA Astrophysics Data System (ADS)

Racek, M.; Lexa, O.; Schulmann, K.; Corsini, M.; Štípská, P.; Maierová, P.

2017-03-01

A structural and geochronological 40Ar/39Ar study was performed in kilometre-scale middle and lower crustal lens-shaped domains dominated by a preserved subvertical foliation, surrounded by horizontally foliated migmatites. These domains occur within the Moldanubian nappe overlying the Brunia microcontinent at the eastern margin of the European Variscides. Three main deformation phases were recognized: subvertical S2 fabric trending NW-SE in lower crustal rocks and NE-SW in mid-crustal rocks. It is reworked by HT/MT horizontal fabric S3 along margins of crustal domains and in surrounding migmatites. S3 bears a prolate NE lineation parallel to the S2-S3 intersection in the lower crustal domain. In the middle crustal units, L3 is weak, connected to oblate strain and trends NE-SW parallel to the S2-S3 intersection. D4 non-coaxial shear deformation is mainly localized at the boundary between the Moldanubian nappe and Brunia and bears strong top to the NNE shear criteria. In order to constrain kinematics of the D3 deformation, strain modelling was performed to show that the Moldanubian hot nappe was frontally thrust over the Brunia indentor. The renewed D4 tangential movement only heterogeneously reactivates the horizontal S3. This evolution is recorded in 40Ar/39Ar amphibole cooling ages, which show two statistically significant Carboniferous peaks at 342 and 332 Ma, which are also reflected by published detrital muscovite 40Ar/39Ar ages in the adjacent foreland basin. This geochronological record is correlated with progressive erosion of the topographically elevated upper crustal part of the Moldanubian nappe during D3 frontal thrusting, followed by greenschist facies D4 transpressive reactivation and subsequent erosion of high-grade parts of the nappe.

Low temperature thermochronology in the Eastern Alps: Implications for structural and topographic evolution

PubMed Central

Wölfler, Andreas; Stüwe, Kurt; Danišík, Martin; Evans, Noreen J.

2012-01-01

According to new apatite fission track, zircon- and apatite (U–Th)/He data, we constrain the near-surface history of the southeastern Tauern Window and adjacent Austrolapine units. The multi-system thermochronological data demonstrate that age-elevation correlations may lead to false implications about exhumation and cooling in the upper crust. We suggest that isothermal warping in the Penninic units that are in the position of a footwall, is due to uplift, erosion and the buildup of topography. Additionally we propose that exhumation rates in the Penninic units did not increase during the Middle Miocene, thus during the time of lateral extrusion. In contrast, exhumation rates of the Austroalpine hangingwall did increase from the Paleogene to the Neogene and the isotherms in this unit were not warped. The new zircon (U–Th)/He ages as well as zircon fission track ages from the literature document a Middle Miocene exhumation pulse which correlates with a period of enhanced sediment accumulation during that time. However, enhanced sedimentation- and exhumation rates at the Miocene/Pliocene boundary, as observed in the Western- and Central Alps, cannot be observed in the Eastern Alps. This contradicts a climatic trigger for surface uplift, and makes a tectonic trigger and/or deep-seated mechanism more obvious to explain surface uplift in the Eastern Alps. In combination with already published geochronological ages, our new data demonstrate Oligocene to Late Miocene fault activity along the Möll valley fault that constitutes a major shear zone in the Eastern Alps. In this context we suggest a geometrical and temporal relationship of the Katschberg-, Polinik–Möll valley- and Mur–Mürz faults that define the extruding wedge in the eastern part of the Eastern Alps. Equal deformation- and fission track cooling ages along the Katschberg–Brenner- and Simplon normal faults demonstrate overall Middle Miocene extension in the whole alpine arc. PMID:27065501

Interpreting Intra-site Spatial Patterns in Seasonal Contexts: an Ethnoarchaeological Case Study from the Western Alps.

PubMed

Carrer, Francesco

2017-01-01

This paper deals with the ethnoarchaeological analysis of the spatial pattern of artefacts and ecofacts within two traditional pastoral huts (a dwelling and a seasonal dairy) in the uplands of Val Maudagna (Cuneo province, Italian western Alps). The composition of the ethnoarchaeological assemblages of the two huts was studied and compared; point pattern analysis was applied to identify spatial processes mirrored in the interactions between objects; Moran's I correlogram and empirical variogram were used to investigate the effects of trampling on the displacement of objects on the floor. The results were compared with information provided by the herder who still used the huts. The quantitative and ethnographical data enabled inferences to be made that can help in the interpretation of archaeological seasonal sites. The function of a seasonal site can be recognized, as can the impact of delayed curation on the composition of the assemblage and the importance of the intensity of occupation compared with the frequency of occupation. The spatial organization of activities is reflected in the spatial patterns of objects, with clearer identification of activity areas in intensively occupied sites, and there is evidence for the behaviour behind the spatial segregation of activities. Trampling is a crucial post-depositional factor in the displacement of artefacts and ecofacts, especially in non-intensively exploited sites. From a methodological point of view, this research is another example that highlights the importance of integrating quantitative methods (especially spatial analysis and geostatistical methods) and ethnoarchaeological data in order to improve the interpretation of archaeological sites and assemblages.

Pre-Alpine (Variscan) Inheritance: A Key for the Location of the Future Valaisan Basin (Western Alps)

NASA Astrophysics Data System (ADS)

Ballèvre, M.; Manzotti, P.; Dal Piaz, G. V.

2018-03-01

The boundary between the Helvetic and the Penninic (=Briançonnais) Zones has long been recognized as a major fault ("Penninic Front") in the Western Alps. A narrow oceanic domain has been postulated at least along part of this boundary (the Valaisan Basin). However, the information provided by the pre-Triassic basement has not been fully exploited and will be discussed here in detail. The igneous and metamorphic history of the pre-Triassic basement shows significant differences between the External Massifs from the Helvetic Zone, with abundant Late Carboniferous granites, and the basement of the Briançonnais Zone, including the Internal Massifs (Dora-Maira, Gran Paradiso, and Monte Rosa), devoid of Carboniferous granites. A major coal-bearing basin, the "Zone Houillère," opened along this boundary. This limnic intramontane basin has never been properly investigated. The Zone Houillère is not comparable with the external, paralic, flexural, basins on both sides of the Variscan belt but shows similarities with the Saar-Saale Basin. Like the latter, we interpret the Zone Houillère as a transtensional basin opened along a major, crustal-scale, fault zone, namely, the East Variscan Shear Zone. The Permian magmatism and sedimentation displays contrasting distributions, being absent or very localized in the Helvetic Zone, and widespread in the Penninic Zone. The above data indicate that the structural inheritance from the Variscan belt plays a major role in defining the future location of the Valaisan Basin, that is, the boundary between the European paleomargin and the Briançonnais microcontinent.

The ALP miracle: unified inflaton and dark matter

NASA Astrophysics Data System (ADS)

Daido, Ryuji; Takahashi, Fuminobu; Yin, Wen

2017-05-01

We propose a scenario where both inflation and dark matter are described by a single axion-like particle (ALP) in a unified manner. In a class of the minimal axion hilltop inflation, the effective masses at the maximum and mimimum of the potential have equal magnitude but opposite sign, so that the ALP inflaton is light both during inflation and in the true vacuum. After inflation, most of the ALPs decay and evaporate into plasma through a coupling to photons, and the remaining ones become dark matter. We find that the observed CMB and matter power spectrum as well as the dark matter abundance point to an ALP of mass mphi = Script O(0.01) eV and the axion-photon coupling gphi γ γ = Script O(10-11) GeV-1: the ALP miracle. The suggested parameter region is within the reach of the next generation axion helioscope, IAXO, and high-intensity laser experiments in the future. Furthermore, thermalized ALPs contribute to hot dark matter and its abundance is given in terms of the effective number of extra neutrino species, Δ Neff simeq 0.03, which can be tested by the future CMB and BAO observations. We also discuss a case with multiple ALPs, where the coupling to photons can be enhanced in the early Universe by an order of magnitude or more, which enlarges the parameter space for the ALP miracle. The heavy ALP plays a role of the waterfall field in hybrid inflation, and reheats the Universe, and it can be searched for in various experiments such as SHiP.

Age and prematurity of the Alps

NASA Astrophysics Data System (ADS)

Hergarten, Stefan; Stüwe, Kurt; Wagner, Thomas

2010-05-01

Although the Alps are among the best studied mountain ranges on Earth, the age of their topography is almost unknown. Even their relative stage of evolution is unclear: Are the Alps still growing, in a steady state or even decaying? Using the mean slope at given catchment size as a new geomorphic parameter we analyse the topography of the Alps. Our analysis provides one of the first quantitative constraints that shows that the range is still in its infancy: In contrast to several other mountain ranges, the Alps have still more than half of their evolution to a geomorphic steady state to go. Combining our results with sediment data from the surrounding accumulation spaces we infer that the formation of substantial topography began only 5-6 million years ago. Our results challenge a general consensus that the topographic evolution is distributed over much of the Miocene.

Middle Ordovician subduction of continental crust in the Scandinavian Caledonides: an example from Tjeliken, Seve Nappe Complex, Sweden

NASA Astrophysics Data System (ADS)

Fassmer, Kathrin; Klonowska, Iwona; Walczak, Katarzyna; Andersson, Barbro; Froitzheim, Nikolaus; Majka, Jarosław; Fonseca, Raúl O. C.; Münker, Carsten; Janák, Marian; Whitehouse, Martin

2017-12-01

The Seve Nappe Complex of the Scandinavian Caledonides is thought to be derived from the distal passive margin of Baltica which collided with Laurentia in the Scandian Phase of the Caledonian Orogeny at 430-400 Ma. Parts of the Seve Nappe Complex were affected by pre-Scandian high- and ultrahigh-pressure metamorphism, in a tectonic framework that is still unclear, partly due to uncertainties about the exact timing. Previous age determinations yielded between 505 and 446 Ma, with a general trend of older ages in the North (Norrbotten) than in the South (Jämtland). New age determinations were performed on eclogite and garnet-phengite gneiss at Tjeliken in northern Jämtland. Thermodynamic modelling yielded peak metamorphic conditions of 25-27 kbar/680-760 °C for the garnet-phengite gneiss, similar to published peak metamorphic conditions of the eclogite (25-26 kbar/650-700 °C). Metamorphic rims of zircons from the garnet-phengite gneiss were dated using secondary ion mass spectrometry and yielded a concordia age of 458.9 ± 2.5 Ma. Lu-Hf garnet-whole rock dating yielded 458 ± 1.0 Ma for the eclogite. Garnet in the eclogite shows prograde major-element zoning and concentration of Lu in the cores, indicating that this age is related to garnet growth during pressure increase, i.e. subduction. The identical ages from both rock types, coinciding with published Sm-Nd ages from the eclogite, confirm subduction of the Seve Nappe Complex in Northern Jämtland during the Middle Ordovician in a fast subduction-exhumation cycle.

Geological structure, recharge processes and underground drainage of a glacierised karst aquifer system, Tsanfleuron-Sanetsch, Swiss Alps

NASA Astrophysics Data System (ADS)

Gremaud, Vivian; Goldscheider, Nico; Savoy, Ludovic; Favre, Gérald; Masson, Henri

2009-12-01

The relationships between stratigraphic and tectonic setting, recharge processes and underground drainage of the glacierised karst aquifer system ‘Tsanfleuron-Sanetsch’ in the Swiss Alps have been studied by means of various methods, particularly tracer tests (19 injections). The area belongs to the Helvetic nappes and consists of Jurassic to Palaeogene sedimentary rocks. Strata are folded and form a regional anticlinorium. Cretaceous Urgonian limestone constitutes the main karst aquifer, overlain by a retreating glacier in its upper part. Polished limestone surfaces are exposed between the glacier front and the end moraine of 1855/1860 (Little Ice Age); typical alpine karrenfields can be observed further below. Results show that (1) large parts of the area are drained by the Glarey spring, which is used as a drinking water source, while marginal parts belong to the catchments of other springs; (2) groundwater flow towards the Glarey spring occurs in the main aquifer, parallel to stratification, while flow towards another spring crosses the entire stratigraphic sequence, consisting of about 800 m of marl and limestone, along deep faults that were probably enlarged by mass movements; (3) the variability of glacial meltwater production influences the shape of the tracer breakthrough curves and, consequently, flow and transport in the aquifer.

A Development Testbed for ALPS-Based Systems

DTIC Science & Technology

1988-10-01

alloted to tile application because of size or power constraints). Given an underlying support ALPS architecture such as the d-ALPS architecture, a...resource on which it is assigned at runtime. A second representation problem is that most graph analysis algorithms treat either graphs with weighted links...subtask) associated with it but is treated like other links. In d-ALPS, as a priority precedence link, it would cause the binding of a pro- cessor: as a

"Fast pedogenesis" on proglacial areas: examples from the north-western Italian Alps

NASA Astrophysics Data System (ADS)

D'Amico, Michele; Freppaz, Michele; Zanini, Ermanno

2013-04-01

Climate changes have huge impacts on alpine ecosystems. One of the most visible effects is glacial retreat since the end of the Little Ice Age (LIA: 190-190 years ago), which caused the exposure of previously glaciated surfaces. These surfaces are open-air laboratories, verifying theories regarding ecosystem and soil development. In order to increase our knowledge on the effect of time and vegetation primary succession on soil development in proglacial areas, we sampled soils and surveyed plant communities on stable points on the proglacial areas of the Lys and Verra Grande glaciers, in the Italian north-western Alps (Valle d'Aosta). Sampling sites were located on dated sites (6-260 years), on the basis of literature or historical photographs). Glacial till is attacked by weathering processes immediately after deposition and stabilization, such as loss of soluble compounds, acidification, primary mineral weathering. The speed of these processes are largely increased after the establishment of a continuous vegetation cover, thanks to surface stabilization, organic matter accumulation caused by litter input and root decomposition below the soil surface. On sialic glacial tills (Lys forefield), below timberline and under a larch - Rhododendron forest, a fast and steady decrease in pH values, increase in organic matter content and horizon differentiation were observed. In particular, genetic eluvial horizons formed in just 60 years, while diagnostic albic horizons were developed after ca. 90 years, evidencing an early start of the podzolization processes. Cheluviation of Fe and, secondarily, Al were analytically verified. However, illuviation of Fe, Al and organic matter in incipient B horizons was not sufficient to obtain diagnostic spodic horizons on LIA materials. Under grazed grassland below timberline and alpine prairie above timberline, acidification and weathering were slightly slower, and no redistribution with depth of Fe and Al oxi-hydroxides was observed. A

Precambrian tholeiitic-dacitic rock-suites and Cambrian ultramafic rocks in the Pennine nappe system of the Alps: Evidence from Sm-Nd isotopes and rare earth elements

USGS Publications Warehouse

Stille, P.; Tatsumoto, M.

1985-01-01

Major element, trace element and Sm-Nd isotope analyses were made of polymetamorphic hornblendefelses, plagioclase amphibolites and banded amphibolites from the Berisal complex in the Simplon area (Italy, Switzerland) to determine their age, origin and genetic relationships. In light of major and rare earth element data, the hornblendefelses are inferred to have originally been pyroxene-rich cumulates, the plagioclase amphibolites and the dark layers of the banded amphibolites to have been tholeiitic basalts and the light layers dacites. The Sm-Nd isotope data yield isochron ages of 475??81 Ma for the hornblendefelses, 1,018??59 Ma for the plagioclase amphibolites and 1,071??43 Ma for the banded amphibolites. The 1 Ga magmatic event is the oldest one ever found in the crystalline basement of the Pennine nappes. The Sm -Nd isotope data support the consanguinity of the tholeiitic dark layers and the dacitic light layers of the banded amphibolites with the tholeiitic plagioclase amphibolites and the ultramafic hornblendefelses. The initial e{open}Nd values indicate that all three rock types originated from sources depleted in light rare earth elements. We suggest that plagioclase and banded amphibolites were a Proterozoic tholeiite-dacite sequence that was strongly deformed and flattened during subsequent folding. The hornblendefelses are thought to be Cambrian intrusions of pyroxene-rich material. ?? 1985 Springer-Verlag.

Precambrian tholeiitic-dacitic rock-suites and Cambrian ultramafic rocks in the Pennine nappe system of the Alps: Evidence from Sm-Nd isotopes and rare earth elements

NASA Astrophysics Data System (ADS)

Stille, P.; Tatsumoto, M.

1985-04-01

Major element, trace element and Sm-Nd isotope analyses were made of polymetamorphic hornblendefelses, plagioclase amphibolites and banded amphibolites from the Berisal complex in the Simplon area (Italy, Switzerland) to determine their age, origin and genetic relationships. In light of major and rare earth element data, the hornblendefelses are inferred to have originally been pyroxene-rich cumulates, the plagioclase amphibolites and the dark layers of the banded amphibolites to have been tholeiitic basalts and the light layers dacites. The Sm-Nd isotope data yield isochron ages of 475±81 Ma for the hornblendefelses, 1,018±59 Ma for the plagioclase amphibolites and 1,071±43 Ma for the banded amphibolites. The 1 Ga magmatic event is the oldest one ever found in the crystalline basement of the Pennine nappes. The Sm -Nd isotope data support the consanguinity of the tholeiitic dark layers and the dacitic light layers of the banded amphibolites with the tholeiitic plagioclase amphibolites and the ultramafic hornblendefelses. The initial ɛ Nd values indicate that all three rock types originated from sources depleted in light rare earth elements. We suggest that plagioclase and banded amphibolites were a Proterozoic tholeiite-dacite sequence that was strongly deformed and flattened during subsequent folding. The hornblendefelses are thought to be Cambrian intrusions of pyroxene-rich material.

Paleotopographic control of landslides in lacustrine deposits (Trièves plateau, French western Alps)

NASA Astrophysics Data System (ADS)

Bièvre, Grégory; Kniess, Ulrich; Jongmans, Denis; Pathier, Erwan; Schwartz, Stéphane; van Westen, Cees J.; Villemin, Thierry; Zumbo, Vilma

2011-01-01

Paleotopography in Quaternary sedimentary environments can be an important factor that controls landslide movement. This study investigates the relation between paleotopography and landslide activity in two adjacent landslides in glaciolacustrine sediments located in the Trièves area (French western Alps). Although both are in slopes underlain by the same lacustrine deposits, the Avignonet and Harmalière landslides exhibit major differences in morphology and displacement rates. Through a combination of geological mapping, airborne light detection and ranging (LiDAR) data, aerial photographs, global positioning system (GPS), and seismic noise measurements, a three-dimensional impression was made of both landslides. The analysis reveals that the difference in kinematics between the two mass movements can be traced back to at least 50 years ago. The results show that the Harmalière slide, which failed catastrophically in 1981, is still much more active than the Avignonet landslide. The fear was that the Avignonet landslide might develop in a similar catastrophic manner, threatening a number of houses constructed on the landslide. A geophysical survey based on ambient noise measurements allowed us to map the base of the lacustrine clays, and the results indicate the presence of a N-S ridge of hard sediments (Jurassic bedrock and/or compact alluvial layers) on the eastern side of the Avignonet landslide. This ridge disappears when approaching the Harmalière landslide and makes a place to what can be interpreted as a NW-SE oriented paleovalley of the river Drac. We proposed that the ridge acts as a buttress that could mechanically prevent the Avignonet landslide from evolving as fast as the Harmalière. Furthermore, the NW-SE paleovalley located under the Harmalière landslide corresponds to the motion direction of the slide. Therefore, the different behaviour of the two landslides is partly controlled by the paleotopographic setting of Lake Trièves during the last

Lithospheric structure of the Western Alps as seen by full-waveform inversion of CIFALPS teleseismic data

NASA Astrophysics Data System (ADS)

Beller, Stephen; Monteiller, Vadim; Operto, Stéphane; Nolet, Guust; Paul, Anne; Zhao, Liang

2017-04-01

Full-waveform inversion (FWI) is a powerful but constitutionally intensive technique that aims to recover 3D multiparameter images of the subsurface by minimising the waveform difference between the full recorded and modelled seismograms. This method has recently been adapted and successfully applied in lithospheric settings by tackling teleseismic waveform modelling with hybrid methods. For each event, a global scale simulation is performed once and for all to store the wavefield solutions on the edges of the lithospheric target. Then, for each modelling involved in the FWI process, these global scale solutions are injected within the lithospheric medium from the boundaries. We present the results of the application of teleseismic FWI to the data acquired by the CIFALPS experiment that was conducted in the Western Alps to gain new insights its lithospheric structure and geodynamic evolution of the alpine range. Nine teleseismic events were inverted to infer 3D models of density, P-wave velocity and S-wave velocity of the crust and the upper-mantle down to 200 km depth. Our models show clear evidences of continental subduction during the alpine orogeny. They outline a dipping European Moho down to 75 km depth and finely delineate the geometry of the Ivrea body at the suture between European and Adriatic plates. Deeper, in the mantle a slow S-wave velocity anomaly might indicate the location of the European slab detachment. Overall, FWI models give access to new seismic images that fill the resolution gap between smooth tomographic model and sharp receiver function images of the lithosphere and enable integrated interpretations of crustal and upper-mantle structures.

Potential toxicity of nonregulated asbestiform minerals: balangeroite from the western Alps. Part 1: Identification and characterization.

PubMed

Groppo, Chiara; Tomatis, Maura; Turci, Francesco; Gazzano, Elena; Ghigo, Dario; Compagnoni, Roberto; Fubini, Bice

2005-01-08

In the Italian western Alps, asbestos mineralization (both chrysotile and tremolite amphibole) takes place from serpentinites, together with other less common asbestiform minerals not regulated by the current legislation. In the context of a study on the evaluation of the asbestos risk in this area, the possible role played by the associated asbestiform minerals in the overall toxicity of the airborne fraction has been examined. The first mineral investigated was balangeroite [(Mg,Fe2+,Fe3+,Mn2+)42Si16O54(OH)36], an iron-rich asbestiform contaminant of chrysotile from the Balangero mine (Piedmont), which crystallizes as rigid and brittle fibers. In order to prepare a sample in a form appropriate for chemical and cellular tests, the fibers were separated from the rock and comminuted without damage to their crystalline structure and surface state (as confirmed by X-ray diffraction [XRD] and ultraviolet-visible [UV-Vis] spectroscopy). The first properties examined were durability in simulated body fluids (Gamble's solution) and toxicity to epithelial cells. When compared to UICC crocidolite (the amphibole blue asbestos, regarded as the most pathogenic form), balangeroite appears even more durable than crocidolite. Balangeroite and UICC crocidolite showed a similar in vitro cytotoxic effect on a human epithelial cell line, as evidenced by leakage of intracellular lactate dehydrogenase (LDH) activity, which, observed after a 24-h incubation, was dose dependent and maximal at 12 microg/cm2 for each fiber type. Data show that chemical composition, form, durability, and cell toxicity indicate balangeroite as a potentially harmful fibrous mineral that needs to be examined by further chemical and cellular tests.

SKS splitting results in central Italy and Dinaric region inside the AlpArray-CASE project

NASA Astrophysics Data System (ADS)

Salimbeni, S.; Prevolnik, S.; Pondrelli, S.; Molinari, I.; Stipcevic, J.; Kissling, E.; Šipka, V.; Herak, M.

2017-12-01

In the framework of the AlpArray project (AlpArray Seismic Network, 2015), the complementary "Central Adriatic Seismic Experiment" (CASE; AlpArray Seismic Network, 2016) was established as collaboration between ETH Zürich, University of Zagreb, INGV and Republic Hydrometeorological Service of Republic of Srpska. The CASE project consists of 9 temporary stations, installed in October 2016, located in Bosnia and Herzegovina, Croatia and Italy. Temporary broadband seismic stations, with the permanent stations present in the region shared by the Croatian Seismological Service and INGV, make an almost continuous transect cutting the Central-Southern Appenines, the central Adriatic region, central External Dinarides and finishing at the eastern margin of the Internal Dinarides. The presence of the the Apenninic and Dinarides slabs, verging in opposite directions and plunging along the opposite sides of the Adriatic plate, make this area a peculiar spot to understand the complex dynamic of the region. Various tomographic images (e.g. Bijwaard and Spakman, 2000; Piromallo and Morelli, 2003) shows not continuous slabs under the Appenines and the Dinarides, suggesting the presence of slab-gaps right beneath the region covered by the CASE experiment. Here we present the preliminary results of the SKS splitting analysis performed on the data recorded by the temporary and permanent seismic stations included in the CASE project. The new results, in combination with previous interpretation, will provide clues about how Northern and Southern Apennines are connected at depth, how the slab rollback of the Apennines thrust belt acted and if and how the Apennines are in relation with the Dinaric region. Together with the measurements from previous studies and from the AlpArray project, our new data will support the mapping of the seismic anisotropy deformation pattern from Western Alps to Pannonian region.

Late Cenozoic extensional faulting in Central-Western Peloponnesus, Greece

NASA Astrophysics Data System (ADS)

Skourtsos, E.; Fountoulis, I.; Mavroulis, S.; Kranis, H.

2012-04-01

A series of forearc-dipping, orogen-parallel extensional faults are found in the central-western Peloponnesus, (south-western Aegean) which control the western margin of Mt Mainalon. The latter comprises HP/LT rocks of the Phyllites-Quartzites Unit (PQ), overlain by the carbonates and flysch of the Tripolis Unit while the uppermost nappe is the Pindos Unit, a sequence of Mesozoic pelagic sequence, topped by a Paleocene flysch. Most of the extensional structures were previously thought of as the original thrust between the Pindos and Tripolis Units. However, the cross-cutting relationships among these structures indicate that these are forearc (SW-dipping) extensional faults, downthrowing the Pindos thrust by a few tens or hundreds of meters each, rooting onto different levels of the nappe pile. In SW Mainalon the lowermost of the extensional faults is a low-angle normal fault dipping SW juxtaposing the metamorphic rocks of the PQ Unit against the non-metamorphic sequence of the Tripolis Unit. High-angle normal faults, found further to the west, have truncated or even sole onto the low-angle ones and control the eastern margin of the Quaternary Megalopolis basin. All these extensional structures form the eastern boundary of a series of Neogene-Quaternary tectonic depressions, which in turn are separated by E-W horsts. In the NW, these faults are truncated by NE to NNE-striking, NW-dipping faults, which relay the whole fault activity to the eastern margin of the Pyrgos graben. The whole extensional fault architecture has resulted (i) in the Pindos thrust stepping down from altitudes higher than 1000 m in Mainalon in the east, to negative heights in North Messinia and Southern Ilia in the west; and (ii) the gradual disappearance of the Phyllite-Quartzite metamorphics of Mainalon towards the west. The combination of these extensional faults (which may reach down to the Ionian décollement) with the low-angle floor thrusts of the Pindos, Tripolis and Ionian Units leads

Cretaceous to Tertiary paleogeographic reconstructions of the Alps-Pyrenees linking zone

NASA Astrophysics Data System (ADS)

Frasca, Gianluca; Dielforder, Armin; Ford, Mary; Vergés, Jaume

2017-04-01

The northwestern Mediterranean subduction systems underwent an important phase of reorganization between Late Cretaceous and Eocene. The mode and timing of this reorganization are still under debate. Great uncertainties mainly derive from the poorly preserved record of the early phases of orogenic evolution in both the Alps and Pyrenees and the distruction of the orogenic system between the Pyrenees and Alps by the Oligo-Miocene opening of the Gulf of Lion due to backarc rifting. Vestiges are nevertheless preserved in the Pyreneo-Provençal fold-and-thrust belt and associated basins in southern France and Corsica-Sardinia. In this work we first review published plate kinematic models for Iberia, Apulia and Europe from 83 Ma, focusing in particular on the restoration of the Corso-Sardinia block using the free software GPlates. Second, we characterize the Upper Cretaceous to Eocene depositional systems at the junction between the Alps, Pyrenees and Apennines, reviewing previous paleogeographic restorations for the Western Alpine and Eastern Pyrenean foreland basins. Last, we compare the kinematic models with reconstructed basin dynamics. We critically assess the implications of newly proposed paleogeographic reconstructions (at 83, 65, 50, 37 and 30 Ma) for the validity of various plate kinematic models. The information derived from the sedimentary basins help to define the mode and timing of the subduction reorganization that occurred between 83 and 30 Ma in the northwestern Mediterranean. This study is part of the Orogen research program funded by Total, the BRGM (Bureau de Recherches Géologiques et Minières), the CNRS (Centre National de la Recherche Scientifique).

The Pan-African nappe tectonics in the Shackleton Range

USGS Publications Warehouse

Buggisch, W.; Kleinschmidt, G.

2007-01-01

In memory of Campbell Craddock: When J. Campbell Craddock (1972) published his famous 1:5 000 000 map of the Geology of Antarctica, he established major units such as the East Antarctic Craton, the early Palaeozoic Ross, the Mesozoic Ellsworth, and the Cenozoic Andean orogens. It is already evident from this map, that the strike of the Ellsworth Mountains and the Shackleton Range is perpendicular to palaeo-Pacific and modern Pacific margins. While the Ellsworth-Whitmore block is classified as a rotated terrane, the Ross-aged orogen of the Shackleton Range requires another interpretation. The discovery of extended tectonic nappes with south directed transport in the southern Shackleton Range and west transport in the north established a plate tectonic scenery with a subduction dominated Ross Orogen in the Transantarctic Mountains and a transpressive tectonic regime in the Shackleton Range during the final closing of the Mozambique Ocean.

Potential toxicity of nonregulated asbestiform minerals: balangeroite from the western Alps. Part 2: Oxidant activity of the fibers.

PubMed

Turci, Francesco; Tomatis, Maura; Gazzano, Elena; Riganti, Chiara; Martra, Gianmario; Bosia, Amalia; Ghigo, Dario; Fubini, Bice

2005-01-08

The asbestiform mineral balangeroite [(Mg,Fe2+,Fe3+,Mn2+)42Si16O54(OH)36], whose toxic potential is unknown, is associated with chrysotile asbestos in the western Alps (Balangero mine, Piedmont, Italy). In order to examine whether such fibers may contribute to the oxidative damage produced by local asbestos dusts when inhaled, balangeroite was studied by means of both cell-free and cellular tests, comparing the results with those concerning the most pathogenic asbestos form, crocidolite. Similarly to the crocidolite surface, iron was mobilized from balangeroite by chelators, to a different extent: deferoxamine > ascorbic acid > ferrozine. Poorly coordinated surface ions, as evaluated from the adsorption of NO as a probe molecule (by both calorimetry and infrared spectroscopy), are even more abundant on balangeroite than on crocidolite. The spin trapping technique shows that surface iron-derived Fenton activity (HO* from H2O2) is similar for the two fiber types, while a pretreatment in ascorbic acid, by reducing previously oxidized surface iron, activates the potential to cleave a C-H bond (yielding *CO2- from formate anion). Balangeroite, like crocidolite, produces nitrite accumulation, lipid peroxidation, and NO synthase activation in a human lung epithelial cell line (A549). All these findings, regarded as features related to the toxic potential of asbestos, suggest that balangeroite may be a potentially hazardous fiber per se and could be partly responsible for lung diseases reported in epidemiological studies in exposed miners.

A Wrench fault system and nappe emplacement in Southern Kenya and Northern Tanzania.- A key area for Pan-African continental collision in East Africa?

NASA Astrophysics Data System (ADS)

Bauernhofer, A.; Wallbrecher, E.; Hauzenberger, C.; Fritz, H.; Loizenbauer, J.; Hoinkes, G.; Muhongo, S.; Mathu, E.

2003-04-01

In the Voi Area of Southern Kenya, the granulite facies rocks of the Taita Hills and the Tsavo East National Park (Galana River) can be divided into three structural domains: The Galana-East unit consists of an intercalation of flat lying metapelites and marbles of continental margin origin. These metasediments can be traced further east to the Umba Steppe (Between Mombasa and Tanga). Galana-West consists of a N-S oriented wrench fault zone with vertical foliation planes and horizontal stretching lineation. Numerous shear sense indicators always show sinistral shear sense. Amphibolites of MORB affinity are involved in this wrench fault zone. To the west, this zone is bordered by calc-alkaline metatonalites of the Sagala Hills. The westernmost unit consists of the Taita Hills. They form an imbricated pile of southwestward thrusted nappe sheets containing metapelites, marbles, and ultramafics. The Taita Hills may be explained as part of an accretionary wedge. Southwestward nappe thrusting is also the prominent structure in the Pare and Usambara Mountains of Northern Tanzania. The following model may may explain these observations: The Southern Kenya -- Northern Tanzania section of the Mozambique Belt is the result of continental collision tectonics. Remnants of an island arc and of an accretionary wedge that occur at least in the Voi area may be part of a former subduction zone. An oceanic domain between an eastern passive continental margin and a western terrane, now represented by the Tanzanian granulite belt has been closed incorporating island arc and accretionary wedge material. Oblique convergence of two continental blocks is suggested from wrench tectonics. The age of convergent tectonics is 530 -- 580 Ma, dated by Sm-Nd garnet-whole rock analysis. This is interpreted as the age of peak metamorphism.

The Variscan evolution in the External massifs of the Alps and place in their Variscan framework

NASA Astrophysics Data System (ADS)

von Raumer, Jürgen F.; Bussy, François; Stampfli, Gérard M.

2009-02-01

In the general discussion on the Variscan evolution of central Europe the pre-Mesozoic basement of the Alps is, in many cases, only included with hesitation. Relatively well-preserved from Alpine metamorphism, the Alpine External massifs can serve as an excellent example of evolution of the Variscan basement, including the earliest Gondwana-derived microcontinents with Cadomian relics. Testifying to the evolution at the Gondwana margin, at least since the Cambrian, such pieces took part in the birth of the Rheic Ocean. After the separation of Avalonia, the remaining Gondwana border was continuously transformed through crustal extension with contemporaneous separation of continental blocks composing future Pangea, but the opening of Palaeotethys had only a reduced significance since the Devonian. The Variscan evolution in the External domain is characterised by an early HP-evolution with subsequent granulitic decompression melts. During Visean crustal shortening, the areas of future formation of migmatites and intrusion of monzodioritic magmas in a general strike-slip regime, were probably in a lower plate situation, whereas the so called monometamorphic areas may have been in an upper plate position of the nappe pile. During the Latest Carboniferous, the emplacement of the youngest granites was associated with the strike-slip faulting and crustal extension at lower crustal levels, whereas, at the surface, detrital sediments accumulated in intramontaneous transtensional basins on a strongly eroded surface.

Kyanite-garnet gneisses of the Kåfjord Nappe - North Norwegian Caledonides: P-T conditions and monazite Th-U-Pb dating

NASA Astrophysics Data System (ADS)

Ziemniak, Grzegorz; Kośmińska, Karolina; Majka, Jarosław; Janák, Marian; Manecki, Maciej

2016-04-01

The Kåfjord Nappe is the part of the Skibotn Nappe Complex traditionally ascribed to the Upper Allochthon of the North Norwegian Caledonides. Pressure-temperature (P-T) conditions and metamorphic age of the Kåfjord Nappe are not well constrained, geochronological data are limited to a single Rb-Sr age of c. 440 Ma (Dangla et al. 1978). Metamorphic evolution of kyanite-garnet gneisses of the Kåfjord Nappe is presented here. The kyanite-garnet gneisses are associated with a few meters thick amphibolite lenses. The gneisses mainly consist of quartz, plagioclase, biotite, muscovite, garnet, kyanite, and rutile. Retrograde minerals are represented by sillimanite and chlorite. Garnet occurs as two textural types. Garnet-I forms euhedral porphyroblasts with multiple small inclusions. Profiles through garnet-I show chemical zonation in all components. The composition varies from Alm64-68Prp11-16Grs13-18Sps2-8 in the core to Alm68-70Prp17-18Grs10-13Sps1-3 in the rim. Garnet-II is subhedral to anhedral, its core is inclusion-rich, whereas rim contains only single inclusions. Chemical composition of garnet-II is similar to that of the garnet-I rim. P-T conditions have been estimated using the garnet-biotite-muscovite-plagioclase (GBPM) geothermobarometer (Holdaway, 2001; Wu, 2014). Calculated peak P-T metamorphic conditions are 610-625 °C and 7.6-8.2 kbar corresponding to the amphibolite facies conditions. Phase equilibrium modelling in the NCKFMMnASH system yields peak metamorphic conditions of c. 620 °C at 8 kbar. Growth conditions of garnet-I core modelled in the NCKFMMnASH system are c. 570 °C at 9.7 kbar. Chemical Th-U-total Pb monazite dating has been performed. Preliminary dating results from the kyanite-garnet gneiss of the Kåfjord Nappe yield an array of dates from 468 Ma to 404 Ma. There is a correlation between an increase of yttrium content and decrease of monazite single dates. Compositional maps confirm an increase of yttrium towards the rim of the

QUANTIFICATION OF GLACIAL EROSION IN THE ALPS USING VERY LOW-TEMPERATURE THERMOCHRONOLOGY (OSL & AHe)

NASA Astrophysics Data System (ADS)

Champagnac, J.; Herman, F.; Rhodes, E. J.; Fellin, M.; Jaiswal, M.; Schwenninger, J.; Reverman, R. L.

2009-12-01

The impact of glaciations on the topography of the Alps is still unclear: Long-term denudation rate determined by low-T thermochronology are in the range of 0.2 to 1 mm/yr, and increased during the Plio-Quaternary by 3 fold (Vernon et al., 2008). Such an increase is also documented by peri-alpine sediment budget (Kuhleman, 2000), with a similar increase in sediment yields since 5-3 Ma. This increase was considered as evidence of a climatically-driven surface process change, attributed to increased precipitation (Cederbom et al., 2004) and erosion by glacial processes (Champagnac et al., 2007). The timing of the onset of intense glacial erosion as well as its rates are still ambiguous. The glacial erosion seems to have accelerated around 0.9 Ma as suggested by the ten fold increase of incision rates of a valley in the Central Alps (Häuselmann et al., 2007), and by information about vegetation and sedimentologic changes (Muttoni et al., 2003). There is however no direct quantification of topographic change during the Plio-Quaternary. We present here how we use OSL-thermochronology, a new thermochronometer of exceptionally low closure temperature (about 30°-40°C) (Herman et al subm.), new {U-Th}/He on apatites data, and a glacial erosion model (Herman and Braun 2008) to estimate topographic changes in the Alps in response to glaciations. Because of their low closure temperature, OSL and AHe thermochronology enables quantification of events of less than 1 Ma at very small wavelength of the topography. We collected two vertical profiles, one in the Zermatt Valley (Valais) and one in Maurienne Valley (Savoy). We infer from these results changes in topography, date and quantify relief creation under glacial-interglacial cycles. Cederbom, C.E, et al., Climate induced rebound and exhumation of the European Alps. Geology 32, 709-712 (2000). Champagnac, J.-D., et al., Quaternary erosion-induced isostatic rebound in the western Alps. Geology 35, 195-198 (2007). Ha

Extragalactic photon-ALP conversion at CTA energies

DOE PAGES

Kartavtsev, A.; Raffelt, G.; Vogel, H.

2017-01-12

Magnetic fields in extragalactic space between galaxy clusters may induce conversions between photons and axion-like particles (ALPs), thereby shielding the photons from absorption on the extragalactic background light. For TeV gamma rays, the oscillation length (l osc) of the photon-ALP system becomes inevitably of the same order as the coherence length of the magnetic field l and the length over which the field changes significantly (transition length l t) due to refraction on background photons. We derive exact statistical evolution equations for the mean and variance of the photon and ALP transfer functions in the non-adiabatic regime (l osc ~more » l >> l t). We also make analytical predictions for the transfer functions in the quasi-adiabatic regime (l osc ALP masses.« less

Brittle/Ductile deformation at depth during continental crust eclogitization (Mont-Emilius klippe, Western Internal Alps).

NASA Astrophysics Data System (ADS)

Hertgen, Solenn; Yamato, Philippe; Morales, Luiz; Angiboust, Samuel

2016-04-01

Eclogitic rocks are important for understanding tectonics at large scale as they provide key constraints on both the evolution (P-T-t-ɛ paths) and the deformation modes of the crust along the subduction interface. We herein focus our study on eclogitized mafic dykes remnants exposed within granulites from the continental basement silver of the Mt. Emilius klippe (Western Internal Alps, Italy). These eclogites exhibit highly deformed garnetite and clinopyroxenite levels. In some places, these rocks with a ± mylonitic aspect can be found as clasts within meter-thick brecciated fault rocks formed close to metamorphic peak conditions in eclogite facies. Especially, the garnet-rich levels tend to behave in a brittle fashion while deformation within clinopyroxene-rich levels is mostly accommodated by creep. This is evidenced by the presence of elongated grains, subgrain boundaries and intense grain size reduction close to rigid garnets. Crystallographic preferred orientation (CPO) measurements in garnets indicate a quasi-random distribution. In most of the clinopyroxenes levels nevertheless, the CPO is relatively strong, with multiples of uniform distribution varying from 4 to 5.5 (value of 1 is random texture). This CPO is characterized by a strong alignment of poles (001) parallel to the lineation and (100) and [010] distributed along girdles cross-cutting the foliation plane. Our study thus attests that the materials along the subduction interface at P~2.0-2.5 GPa and T~500-550°C can locally be brittle where deformation is classically envisioned as ductile. In addition to this deformation analysis, we present a petrological study of these eclogites, from the outcrop to the microscopic scale, tracking the chemical evolution associated to the observed deformation. Based on all these data, we finally propose a tectono-metamorphic history for these rocks allowing to explain the co-existence of ductile and brittle features developed in the same metamorphic facies, and

Climate anomalies associated with the occurrence of rockfalls at high-elevation in the Italian Alps

NASA Astrophysics Data System (ADS)

Paranunzio, Roberta; Laio, Francesco; Chiarle, Marta; Nigrelli, Guido; Guzzetti, Fausto

2016-09-01

Climate change is seriously affecting the cryosphere in terms, for example, of permafrost thaw, alteration of rain / snow ratio, and glacier shrinkage. There is concern about the increasing number of rockfalls at high elevation in the last decades. Nevertheless, the exact role of climate parameters in slope instability at high elevation has not been fully explored yet. In this paper, we investigate 41 rockfalls listed in different sources (newspapers, technical reports, and CNR IRPI archive) in the elevation range 1500-4200 m a.s.l. in the Italian Alps between 1997 and 2013 in the absence of an evident trigger. We apply and improve an existing data-based statistical approach to detect the anomalies of climate parameters (temperature and precipitation) associated with rockfall occurrences. The identified climate anomalies have been related to the spatiotemporal distribution of the events. Rockfalls occurred in association with significant temperature anomalies in 83 % of our case studies. Temperature represents a key factor contributing to slope failure occurrence in different ways. As expected, warm temperatures accelerate snowmelt and permafrost thaw; however, surprisingly, negative anomalies are also often associated with slope failures. Interestingly, different regional patterns emerge from the data: higher-than-average temperatures are often associated with rockfalls in the Western Alps, while in the Eastern Alps slope failures are mainly associated with colder-than-average temperatures.

Gene Expression of Lytic Endopeptidases AlpA and AlpB from Lysobacter sp. XL1 in Pseudomonads.

PubMed

Tsfasman, Irina M; Lapteva, Yulia S; Krasovskaya, Ludmila A; Kudryakova, Irina V; Vasilyeva, Natalia V; Granovsky, Igor E; Stepnaya, Olga A

2015-01-01

Development of an efficient expression system for (especially secreted) bacterial lytic enzymes is a complicated task due to the specificity of their action. The substrate for such enzymes is peptidoglycan, the main structural component of bacterial cell walls. For this reason, expression of recombinant lytic proteins is often accompanied with lysis of the producing bacterium. This paper presents data on the construction of an inducible system for expression of the lytic peptidases AlpA and AlpB from Lysobacter sp. XL1 in Pseudomonas fluorescens Q2-87, which provides for the successful secretion of these proteins into the culture liquid. In this system, the endopeptidase gene under control of the T7lac promoter was integrated into the bacterial chromosome, as well as the Escherichia coli lactose operon repressor protein gene. The T7 pol gene under lac promoter control, which encodes the phage T7 RNA polymerase, is maintained in Pseudomonas cells on the plasmids. Media and cultivation conditions for the recombinant strains were selected to enable the production of AlpA and AlpB by a simple purification protocol. Production of recombinant lytic enzymes should contribute to the development of new-generation antimicrobial drugs whose application will not be accompanied by selection of resistant microorganisms. © 2015 S. Karger AG, Basel.

Mantle wedge exhumation beneath the Dora-Maira (U)HP dome unravelled by local earthquake tomography (Western Alps)

NASA Astrophysics Data System (ADS)

Solarino, Stefano; Malusà, Marco G.; Eva, Elena; Guillot, Stéphane; Paul, Anne; Schwartz, Stéphane; Zhao, Liang; Aubert, Coralie; Dumont, Thierry; Pondrelli, Silvia; Salimbeni, Simone; Wang, Qingchen; Xu, Xiaobing; Zheng, Tianyu; Zhu, Rixiang

2018-01-01

In continental subduction zones, the behaviour of the mantle wedge during exhumation of (ultra)high-pressure [(U)HP] rocks provides a key to distinguish among competing exhumation mechanisms. However, in spite of the relevant implications for understanding orogenic evolution, a high-resolution image of the mantle wedge beneath the Western Alps is still lacking. In order to fill this gap, we perform a detailed analysis of the velocity structure of the Alpine belt beneath the Dora-Maira (U)HP dome, based on local earthquake tomography independently validated by receiver function analysis. Our results point to a composite structure of the mantle wedge above the subducted European lithosphere. We found that the Dora-Maira (U)HP dome lays directly above partly serpentinized peridotites (Vp 7.5 km/s; Vp/Vs = 1.70-1.72), documented from 10 km depth down to the top of the eclogitized lower crust of the European plate. These serpentinized peridotites, possibly formed by fluid release from the subducting European slab to the Alpine mantle wedge, are juxtaposed against dry mantle peridotites of the Adriatic upper plate along an active fault rooted in the lithospheric mantle. We propose that serpentinized mantle-wedge peridotites were exhumed at shallow crustal levels during late Eocene transtensional tectonics, also triggering the rapid exhumation of (U)HP rocks, and were subsequently indented under the Alpine metamorphic wedge in the early Oligocene. Our findings suggest that mantle-wedge exhumation may represent a major feature of the deep structure of exhumed continental subduction zones. The deep orogenic levels here imaged by seismic tomography may be exposed today in older (U)HP belts, where mantle-wedge serpentinites are commonly associated with coesite-bearing continental metamorphic rocks.

Collision in the Central Alps: 2. Exhumation of high-pressure fragments

NASA Astrophysics Data System (ADS)

Brouwer, F. M.; Burri, T.; Berger, A.; Engi, M.

2003-04-01

In the Central Alps high-pressure metamorphic rocks are confined to but a few tectonic units. In the Adula nappe pressures range from about 12 kbar in the north, to 20 kbar in the south [1]. The Southern Steep Belt (SSB) is a high-strain zone at the contact between rocks deriving from Apulia and Eurasia. The SSB contains a tectonic composite of ortho and paragneisses, with widespread bands and lenses of mafic and ultramafic composition. Many of the mafic fragments are garnet-amphibolites or eclogites, with a highly variable degree of retrogression. Our petrological studies indicate that the HP rocks in the SSB show extensive variation in metamorphic pressure. In mafic fragments, pressures retained by assemblages predating the amphibolite facies overprint range from 8 to 21 kbar, while pressure estimates for some peridotites are >30 kbar. Some HP fragments show evidence of substantial heating during decompression. New Lu-Hf and Sm-Nd geochronology, in conjunction with previously published data, indicates a spread in ages obtained from the high-pressure metamorphic assemblage. Thermal models based on simplified kinematics produce computed PTt histories that resemble those documented in individual HP fragments [2]. The SSB is interpreted to represent an exhumed part of a Tectonic Accretion Channel (TAC, cf. [3]), assembled of numerous, relatively small fragments which reflect a variety of paths. The different residence times and exhumation rates reflect a protracted history of subduction and extrusion, in which the fragments moved independently from their current neighbours. Combination of thermal modelling and field-based studies improve our conceptual thinking on the dynamics of exhumation of high-pressure rocks in a convergent orogen. [1] Heinrich (1986) J. Pet. 27: 123-154 [2] Roselle et al. (2002) Amer. J. Sci. 302: 381-409 [3] Engi et al. (2001) Geology 29: 1143-1146

The XMAP215 Ortholog Alp14 Promotes Microtubule Nucleation in Fission Yeast.

PubMed

Flor-Parra, Ignacio; Iglesias-Romero, Ana Belén; Chang, Fred

2018-06-04

The organization and number of microtubules (MTs) in a cell depend on the proper regulation of MT nucleation. Currently, the mechanism of nucleation is the most poorly understood aspect of MT dynamics. XMAP215/chTOG/Alp14/Stu2 proteins are MT polymerases that stimulate MT polymerization at MT plus ends by binding and releasing tubulin dimers. Although these proteins also localize to MT organizing centers and have nucleating activity in vitro, it is not yet clear whether these proteins participate in MT nucleation in vivo. Here, we demonstrate that in the fission yeast Schizosaccharomyces pombe, the XMAP215 ortholog Alp14 is critical for efficient MT nucleation in vivo. In multiple assays, loss of Alp14 function led to reduced nucleation rate and numbers of interphase MT bundles. Conversely, activation of Alp14 led to increased nucleation frequency. Alp14 associated with Mto1 and γ-tubulin complex components, and artificially targeting Alp14 to the γ-tubulin ring complexes (γ-TuRCs) stimulated nucleation. In imaging individual nucleation events, we found that Alp14 transiently associated with a γ-tubulin particle shortly before the appearance of a new MT. The transforming acidic coiled-coil (TACC) ortholog Alp7 mediated the localization of Alp14 at nucleation sites but not plus ends, and was required for efficient nucleation but not for MT polymerization. Our findings provide the strongest evidence to date that Alp14 serves as a critical MT nucleation factor in vivo. We suggest a model in which Alp14 associates with the γ-tubulin complex in an Alp7-dependent manner to facilitate the assembly or stabilization of the nascent MT. Copyright © 2018 Elsevier Ltd. All rights reserved.

Deep thermal disturbances related to the sub-surface groundwater flow (Western Alps, France)

NASA Astrophysics Data System (ADS)

Mommessin, Grégoire; Dzikowski, Marc; Menard, Gilles; Monin, Nathalie

2013-04-01

In mountain area, the bedrock of the valley side is affected by a thickness of decompressed rock in subsurface (decompressed zone). Groundwater flowing in this zone disrupts the depth geothermal gradients. The evolution of thermal gradients under the decompressed zone depends of groundwater temperature changes into the decompressed zone. In this study, the phenomenon is studied from data acquired in exploration drilling prior to the construction of the France - Italy transalpine tunnel (High Speed Line project between Lyon and Turin). The study area is located in the Vanoise siliceous series between Modane and Avrieux (Western Alps, France). Of 31 boreholes, we selected 14 wells showing a natural thermal disturbance (not due to the drilling) linked to the groundwater flow in decompressed zone. The drill holes have a length between 200 and 1380m and well logs were carried out (gamma log, acoustic log, temperature log, flowmeter log). The rocks are constituted mainly by quartzite with high thermal conductivity or by schist and gneiss with low thermal conductivity. The decompressed zone concerns the quartzite with thicknesses ranging from 50m to 750m where groundwater flow imposes a constant temperature throughout the rock thickness. In the very low permeability rocks under the decompressed zone, the thermal gradient shows variations with depth. These variations suggest a water temperature change in the decompressed zone probably due to a paleoclimate event. We used the derived of the equation describing the propagation of a temperature in a 1D semi-infinite, in response to a sudden temperature disturbance at the boundary of the medium, to estimate the age and the amplitude of temperature change in the decompressed zone. The medium under the decompressed zone is supposed to be initially in a steady state and only conductive. Numerical tests assess that the 1D model is applicable in the slope context. The results obtained from 13 wells data show a few warming degrees

Structural and exhumational response to oroclinal bending at the Eastern Alps - Western Carpathian transition

NASA Astrophysics Data System (ADS)

Heberer, Bianca; Neubauer, Franz

2017-04-01

Curvature is an intriguing feature within many mountain belts worldwide. Several proposals have been made for deciphering the origin of curvature, however, there is still significant debate about the bend-forming mechanisms, the consequences as well as on how bending is accommodated within the lithosphere. Only few of the worldwide oroclines have been studied in detail and a variety of alternative controlling factors, such as the role of inherited structures, the rheological coupling between lower and upper plates, the presence of a basement promontory in the foreland and its particular geometry, and lateral orogen-parallel extrusion are likely underestimated or not considered at all. This study focuses on oroclinal bending at the transition from the W-E trending Eastern Alps to the SW-NE oriented Western Carpathians. There, the orogenic front is concave towards the Alpine foreland and the greatest degree of curvature (ca. 55°) is found adjacent to the Bohemian massif. The oroclinal axis runs from the Bohemian promontory to the South Burgenland high. Various competing mechanisms occurred, i.e. rotation around a stiff foreland promontory and lateral extrusion induced by tectonic escape due to the indentation of a microplate and extensional collapse due to slab-rollback beneath the Carpathians. Little is known for such cases, where bending around as well as overriding of a promontory occurs, particularly on how it controls the exhumational and structural architecture within the orogen itself. Based on a synthesis of low-T thermochronology and structural data we find a significant impact of oroclinal bending on exhumation and structures: Highest amounts of erosion occur in the immediate vicinity of the Bohemian promontory and along its prolongation in the South Burgenland high, corroborating that shortening and exhumation are most pronounced there and should decrease along-strike of the orogenic front. In the outer bend strong Miocene extensional thinning parallel to

SALMON-TRINITY ALPS WILDERNESS, CALIFORNIA.

USGS Publications Warehouse

Hotz, Preston E.; Thurber, Horace K.

1984-01-01

The Salmon-Trinity Alps Wilderness in the Klamath Mountains province occupies an area of about 648 sq mi in parts of Trinity, Siskiyou, and Humboldt Counties, northwestern California. As a result of field studies it was determined that the Salmon-Trinity Alps Wilderness has an area with substantiated potential for gold resources in known lode deposits. Small amounts of quicksilver have been produced from one mine but there is little promise for the discovery of additional mercury resources. Geochemical sampling showed that anomalously high amounts of several other metals occur in a few places, but there is little promise for the discovery of energy or mineral resources other than mercury and gold.

Basement diapirism associated with the emplacement of major ophiolite nappes: Some constraints

NASA Astrophysics Data System (ADS)

Andrews-Speed, C. P.; Johns, C. C.

1985-09-01

The association of basement uplifts with major ophiolite nappes in some Phanerozoic orogenic belts suggests that gravitational instability results in the local diapiric uplift of the basement following ophiolite emplacement. In previous analyses of diapirism in crustal silicate rocks, viscous behaviour of rocks has been assumed. It is argued that this assumption is not valid. An alternative analysis is offered to determine whether or not the stress would be sufficient for diapirism to occur. The negative buoyancy stress resulting from the emplacement of an ophiolite nappe 5-15 km thick onto continental basement may be in the range 10-50 MPa. If the horizontal deviatoric stress is zero, this will be the maximum principal compressive stress. After ophiolite emplacement the thermal profile through the ophiolite and the basement will relax from a saw-tooth form to an equilibrium profile. If the ophiolite is young and thick there will be a zone of ductile strain in the lower part of the ophiolite and in the upper part of the continental basement. Results from steady-state creep experiments suggest that temperatures in this zone may be high enough for a short time after ophiolite emplacement (3 Ma or more) for the rocks in this zone to deform at geologically significant strain rates (10 -14 or greater) in response to the negative buoyancy stress. A thin ophiolite or rapid erosion will result in this ductile zone being absent or too short-lived for significant strain. Aquaeous fluids may reduce the strength of brittle rocks by decreasing the effective normal stress or by encouraging pressure solution creep. Evidence suggests that the deviatoric stress across presently active faults may be as low at 10 MPa. Thus diapirism in response to ophiolite emplacement may occur through brittle strain. Gravity spreading within the ophiolite is an alternative mechanism for accommodating the gravitational instability. The critical evidence lies in the field.

Fission yeast Alp14 is a dose-dependent plus end–tracking microtubule polymerase

PubMed Central

Al-Bassam, Jawdat; Kim, Hwajin; Flor-Parra, Ignacio; Lal, Neeraj; Velji, Hamida; Chang, Fred

2012-01-01

XMAP215/Dis1 proteins are conserved tubulin-binding TOG-domain proteins that regulate microtubule (MT) plus-end dynamics. Here we show that Alp14, a XMAP215 orthologue in fission yeast, Schizosaccharomyces pombe, has properties of a MT polymerase. In vivo, Alp14 localizes to growing MT plus ends in a manner independent of Mal3 (EB1). alp14-null mutants display short interphase MTs with twofold slower assembly rate and frequent pauses. Alp14 is a homodimer that binds a single tubulin dimer. In vitro, purified Alp14 molecules track growing MT plus ends and accelerate MT assembly threefold. TOG-domain mutants demonstrate that tubulin binding is critical for function and plus end localization. Overexpression of Alp14 or only its TOG domains causes complete MT loss in vivo, and high Alp14 concentration inhibits MT assembly in vitro. These inhibitory effects may arise from Alp14 sequestration of tubulin and effects on the MT. Our studies suggest that Alp14 regulates the polymerization state of tubulin by cycling between a tubulin dimer–bound cytoplasmic state and a MT polymerase state that promotes rapid MT assembly. PMID:22696680

The AlpArray-CASE project: temporary broadband seismic network deployment and characterization

NASA Astrophysics Data System (ADS)

Dasović, Iva; Molinari, Irene; Stipčević, Josip; Šipka, Vesna; Salimbeni, Simone; Jarić, Dejan; Prevolnik, Snježan; Kissling, Eduard; Clinton, John; Giardini, Domenico

2017-04-01

While the northern part of the Adriatic microplate will be accurately imaged within the AlpArray project, its central and southern parts deserve detailed studies to obtain a complete picture of its structure and evolution. The Adriatic microplate forms the upper plate in the Western and Central Alps whereas it forms the lower plate in the Apennines and the Dinarides. However, the tectonics of Adriatic microplate is not well constrained and remains controversial, especially with regard to its contact with the Dinarides. The primary goal of the Central Adriatic Seismic Experiment (CASE) is to provide high quality seismological data and to shed light on seismicity and 3D lithospheric structure of the central Adriatic microplate and its boundaries. The CASE project is an international AlpArray Complementary Experiment carried out by four institutions: Department of Earth Sciences and Swiss Seismological Service of ETH Zürich (CH), Department of Geophysics and Croatian Seismological Service of Faculty of Science at University of Zagreb (HR), Republic Hydrometeorological Service of Republic of Srpska (BIH) and Istituto Nazionale di Geofisica e Vulcanologia (I). It establishes a temporary seismic network, expected to be operational at least for one year, composed by existing permanent and temporary seismic stations operated by the institutions involved and newly deployed temporary seismic stations, installed in November and December 2016, provided by ETH Zürich and INGV: five in Croatia, four in Bosnia and Herzegovina and two in Italy. In this work, we present stations sites and settings and discuss their characteristics in terms of site-effects and noise level of each station. In particular, we analyse the power spectral density estimates in order to investigate major sources of noise and background noise.

Any Light Particle Search (ALPS)

NASA Astrophysics Data System (ADS)

Spector, Aaron; Any Light Particle Search (ALPS) Collaboration

2016-03-01

High power laser fields enabled by technologies developed for ground-based gravitational-wave observatories open up new opportunities for fundamental physics studies. One of these options is the search for axions and axion-like particles in a pure laboratory experiment. The axion is a solution to the strong CP-problem and a potential dark matter candidate. The axion has also been proposed as an additional channel to cool stars as well as a potential explanation for the TeV transparency problem. The German-US ALPS collaboration is setting up a light-shining-through-walls (LSW) experiment at DESY. LSW experiments are based on the simple idea that a high power laser field traversing a static magnetic field will transform partly into a relativistic axion field. This axion field will travel through an opaque wall into a second static magnetic field region where it turns partly back into an electromagnetic wave field with the same frequency as the laser. The ALPS collaboration is working towards a large scale LSW experiment at DESY in Hamburg, Germany. I will report on the status of the ALPS experiment. This work is supported by the Deutsche Forschungsgemeinschaft, PRISMA, the Helmholtz Association, the National Science Foundation and the Heising-Simons Foundation.

A Bi-hemispheric perspective on the last glacial termination from the Southern Alps of New Zealand and the Altai Mountains of western Mongolia

NASA Astrophysics Data System (ADS)

Strand, P.; Putnam, A. E.; Schaefer, J. M.; Denton, G.; Putnam, D.; Barrell, D.; Schwartz, R.; Sambuu, O.

2016-12-01

The last glacial termination ( 18,000 - 11,000 yrs ago) represents the last great global warming and the last time CO2 rose by a substantial amount before the industrial period. Understanding the processes that drove this glacial to interglacial transition will help refine the global climate system sensitivity to CO2 and will place ongoing global warming into a paleoclimatic context. Here, we test possible drivers of the last glacial termination by comparing chronologies of mountain glacier recession in the middle latitudes of both polar hemispheres. Extra-polar mountain glaciers are highly sensitive to changes in atmospheric temperature. Thus glacier landforms, such as moraine ridges constructed along glacier margins, afford quantitative insight into past climate conditions. We present 10Be surface-exposure chronologies and glacial geomorphologic maps of mountain glacier recession since the Last Glacial Maximum in the Southern Alps of New Zealand (44°S, 170°E) and in the Altai Mountains of western Mongolia (49°N, 88°E). On the basis of these chronologies from opposing hemispheres, we will evaluate the relative roles of rising atmospheric CO2, local insolation forcing, and ocean-atmosphere reorganizations in driving the warming that ended the last ice age.

Thermochronometry Across the Austroalpine-Pennine Boundary, Central Alps, Switzerland: Orogen-Perpendicular Normal Fault Slip on a Major "Overthrust" and Its Implications for Orogenesis

NASA Astrophysics Data System (ADS)

Price, Jason B.; Wernicke, Brian P.; Cosca, Michael A.; Farley, Kenneth A.

2018-03-01

Fifty-one new and 309 published thermochronometric ages (nine systems with closure temperatures ranging from 450 to 70°C) from the Graubünden region of the Central Alps demonstrate that a pronounced thermal mismatch between the Austroalpine allochthon (Alpine "orogenic lid") and the Pennine zone persisted until at least 29 Ma and, allowably, until circa 18 Ma. The observed mismatch supports previous suggestions that the famous "overthrust" between the Austroalpine allochthon and the Pennine zone, historically regarded as primarily an Eocene top-north thrust fault, is in fact primarily an Oligocene-Miocene normal fault that has a minimum of 60 km of displacement with top-south or top-southeast sense of shear. Two hallmarks of Alpine geology, deposition of the foredeep Molasse and emplacement of the Helvetic nappes, appear to be coeval, peripheral manifestations of crustal thickening via the interposition of the Pennine zone as a northward intruding wedge between the Austroalpine "lid" and the European cratonic margin, with the Helvetic system (European margin) acting as the "floor" of the wedge. We presume the Penninic wedge is driven by the buoyant rise of subducted crust no longer able to remain attached to the descending slab. If so, emplacement of the Pennine wedge could have occurred mainly after Adria was juxtaposed against cratonic Europe.

Detecting glacier-bed overdeepenings for glaciers in the Western Italian Alps using the GlabTop2 model: the test site of the Rutor Glacier, Aosta Valley

NASA Astrophysics Data System (ADS)

Viani, Cristina; Machguth, Horst; Huggel, Christian; Perotti, Luigi; Giardino, Marco

2016-04-01

detecting the overdeepenings (6 were identified) and their location. Regarding their size, it seems to be influenced by the resolution of input data: the total overdeepended area covers about 1,3 km2 in the case of 25m pixel size and about 0,6 km2 in the 75m one. Based on the results obtained with model application and verification at Rutor Glacier, GlapTop2 will be applied over larger areas of the Western Italian Alps (Piemonte and Aosta Valley) in order to assess locations of possible future lakes to facilitate identification of potentially hazardous conditions and dynamics.

Younger Dryas Age advance of Franz Josef Glacier in the Southern Alps of New Zealand

DOE Office of Scientific and Technical Information (OSTI.GOV)

Denton, G.H.; Hendy, C.H.

1994-06-03

A corrected radiocarbon age of 11,050 [+-] 14 years before present for an advance of the Franz Josef Glacier to the Waiho Loop terminal moraine on the western flank of New Zealand's Southern Alps shows that glacier advance on a South Pacific island was synchronous with initiation of the Younger Dryas in the North Atlantic region. Hence, cooling at the beginning of the Younger Dryas probably reflects global rather than regional forcing. The source for Younger Dryas climatic cooling may thus lie in the atmosphere rather than in a North Atlantic thermohaline switch. 36 refs., 2 figs., 1 tab.

Evidence for brittle deformation events at eclogite-facies P-T conditions (example of the Mt. Emilius klippe, Western Alps)

NASA Astrophysics Data System (ADS)

Hertgen, Solenn; Yamato, Philippe; Morales, Luiz F. G.; Angiboust, Samuel

2017-06-01

Eclogitic rocks are crucial for the understanding of tectonic processes as they provide key constraints on both the P-T-t evolutions and the deformation modes sustained by rocks in subduction zones. Here we focus on eclogitised and deformed mafic bodies that are exposed within granulites from the continental basement slice of the Mt. Emilius klippe (Western Alps, Italy). These eclogites exhibit highly deformed garnetite and clinopyroxenite layers. In some places, these deformed rocks (up to mylonitic grade) can be found as clasts within meter-thick brecciated fault rocks that formed close to the lawsonite-eclogite facies peak P-T conditions. Garnet-rich layers are dominated by brittle features, whereas deformation within clinopyroxene-rich layers is accommodated by both creep and fracturing. We present a petro-structural study of these eclogites, that allows to track the brittle deformation history associated with chemical evolution. Based on these data, we propose a new tectono-metamorphic model for these rocks, related to the alpine eclogitic stage. This model is consistent with the coexistence of both ductile and brittle features that developed at similar P-T conditions (i.e., at P 2.15-2.40 GPa and T 500-550 °C), and closely associated with fluid circulations. Our study demonstrates that crustal material, buried along the subduction interface at HP-LT conditions, can record several successive brittle events in places where deformation is classically envisioned as ductile. We suggest, based on our observations, that strain-rate increase along plate interface shear zones may trigger fracturing and fluid infiltration which in turn enables brittle-ductile instabilities along these deformation networks.

Palaeoglaciology of the Central European Uplands - a link between the former ice masses over the Alps and Scandinavia

NASA Astrophysics Data System (ADS)

Hauzenberger, B.; Fickert, T.

2009-04-01

The Central European Uplands are located northeast of the Alps along the western edge of the Czech border. A horseshoe shaped range of low mountains contains the Bavarian Forest Mountains, the Fichtel Mountains, the Erz Mountains and the Giant Mountains, with highest summit altitudes ranging from 1051 m a.s.l. (Fichtel Mountains) to 1603 m a.s.l. (Giant Mountains). The location north of the Alps makes these mountains highly interesting as a possible link between the Scandinavian ice sheet and the Alps. Although the glacial traces of the Central European Uplands have been investigated for more than 100 years, the glacial history is still elusive. While the highest mountains (the Bavarian Forest and the Giant Mountains) hold evidence of valley glaciers, the lower mountains (the Fichtel and the Erz Mountains) lack unambiguous glacial traces. As a first step towards a palaeoglaciological reconstruction for the Central European Uplands, we present a digital map of glacier termini with elevation data from the SRTM elevation model, compiled from previous investigations of the area. The glacial map of the Central European Uplands presents the pattern of glacial traces over an extensive area in central Europe and forms the basis for reconstructing the extent of former glaciers. We compare the glacial evidence with modern day climate data (from the high resolution WorldClim database), from which we can estimate the climate change needed to produce Central European Upland glaciers. The glacial traces of the Central European Uplands hold information on past climate of the region and this may be a key to link the glacial record of the Alps with the Scandinavian ice sheet.

Investigation of the Sultan Alp Arslan tomb with geophysical methods, in the historical Merv city (Turkestan)

NASA Astrophysics Data System (ADS)

Kadioglu, Selma; Kagan Kadioglu, Yusuf

2016-04-01

Sultan Alp Arslan (1029-1072) was the second Sultan of the Seljuq Empire and great-grandson of Seljuq the eponymous founder of the dynasty. Sultan Alp Arslan's victories changed the balance in near Asia completely in favour of the Seljuq Turks and Sunni Muslims. His victory at Manzikert (26 August 1071) is often cited as the beginning of the end of Byzantine power in Anatolia, and the beginning of Turkish identity in Anatolia. Sultan Alp Arslan eliminated theobstacles to the conquest of Anatolia and played a major role in making this territory a homeland for the Seljuqs. By taking the Emperor captive, Sultan Alp Arslan gained great fame but in 1072, on an expedition to Western Turkestan, he met with death in an unexpected way and at a relatively early age, in his 42nd year. There have been found different stories of the death of this great Turkish Sultan in certain sources. Unfortunately, there has not been found The Sultan's resting place until now. This paper is concerned with the investigation of the Sultan Alp Arslan Tomb in the historical Merv (Marv) city in Turkestan, by using Ground Penetrating Radar (GPR) and gradiometer methods. The GPR and gradiometer surveys have been realized in Gavur Fortress, Sultan Fortress, Er Fortress districts and between two big Fortresses in old Merv city in selected nine study areas. We also gathered data in and around Sultan Sancar Tomb. GPR surveys were performed during January 2014 employing Ramac CU-II system equipped with a 250 MHz shielded antenna, on one meter spaced profiles. Similarly a Geoscan system was used to take magnetic data. The results of all these investigation revealed that there were possible traces for the buried tomb of the Sultan Alparslan in Gavur Kale around Cuma Mosque and around Sultan Sancar Tomb in the study region. However, the project team was changed after our study, and the new team did not excavated our determined areas. Acknowledgement This project has been supported by Republic of Turkey

Structure of Accelerated Learning Program (ALP) Efforts, 2000-01.

ERIC Educational Resources Information Center

Baenen, Nancy; Yaman, Kimberly

This report focuses on the structure of instructional assistance available through the Accelerated Learning Program (ALP) to students who show low achievement in the Wake County Public School System (WCPSS), North Carolina. Context information is also provided on other programs available to these students. Reports on ALP student participation,…

End of the Little Ice Age in the Alps forced by industrial black carbon

PubMed Central

Painter, Thomas H.; Flanner, Mark G.; Kaser, Georg; Marzeion, Ben; VanCuren, Richard A.; Abdalati, Waleed

2013-01-01

Glaciers in the European Alps began to retreat abruptly from their mid-19th century maximum, marking what appeared to be the end of the Little Ice Age. Alpine temperature and precipitation records suggest that glaciers should instead have continued to grow until circa 1910. Radiative forcing by increasing deposition of industrial black carbon to snow may represent the driver of the abrupt glacier retreats in the Alps that began in the mid-19th century. Ice cores indicate that black carbon concentrations increased abruptly in the mid-19th century and largely continued to increase into the 20th century, consistent with known increases in black carbon emissions from the industrialization of Western Europe. Inferred annual surface radiative forcings increased stepwise to 13–17 W⋅m−2 between 1850 and 1880, and to 9–22 W⋅m−2 in the early 1900s, with snowmelt season (April/May/June) forcings reaching greater than 35 W⋅m−2 by the early 1900s. These snowmelt season radiative forcings would have resulted in additional annual snow melting of as much as 0.9 m water equivalent across the melt season. Simulations of glacier mass balances with radiative forcing-equivalent changes in atmospheric temperatures result in conservative estimates of accumulating negative mass balances of magnitude −15 m water equivalent by 1900 and −30 m water equivalent by 1930, magnitudes and timing consistent with the observed retreat. These results suggest a possible physical explanation for the abrupt retreat of glaciers in the Alps in the mid-19th century that is consistent with existing temperature and precipitation records and reconstructions. PMID:24003138

End of the Little Ice Age in the Alps forced by industrial black carbon.

PubMed

Painter, Thomas H; Flanner, Mark G; Kaser, Georg; Marzeion, Ben; VanCuren, Richard A; Abdalati, Waleed

2013-09-17

Glaciers in the European Alps began to retreat abruptly from their mid-19th century maximum, marking what appeared to be the end of the Little Ice Age. Alpine temperature and precipitation records suggest that glaciers should instead have continued to grow until circa 1910. Radiative forcing by increasing deposition of industrial black carbon to snow may represent the driver of the abrupt glacier retreats in the Alps that began in the mid-19th century. Ice cores indicate that black carbon concentrations increased abruptly in the mid-19th century and largely continued to increase into the 20th century, consistent with known increases in black carbon emissions from the industrialization of Western Europe. Inferred annual surface radiative forcings increased stepwise to 13-17 W⋅m(-2) between 1850 and 1880, and to 9-22 W⋅m(-2) in the early 1900s, with snowmelt season (April/May/June) forcings reaching greater than 35 W⋅m(-2) by the early 1900s. These snowmelt season radiative forcings would have resulted in additional annual snow melting of as much as 0.9 m water equivalent across the melt season. Simulations of glacier mass balances with radiative forcing-equivalent changes in atmospheric temperatures result in conservative estimates of accumulating negative mass balances of magnitude -15 m water equivalent by 1900 and -30 m water equivalent by 1930, magnitudes and timing consistent with the observed retreat. These results suggest a possible physical explanation for the abrupt retreat of glaciers in the Alps in the mid-19th century that is consistent with existing temperature and precipitation records and reconstructions.

Phylogeography and recolonization of the Swiss Alps by the Valais shrew (Sorex antinorii), inferred with autosomal and sex-specific markers.

PubMed

Yannic, G; Basset, P; Hausser, J

2008-09-01

Using one male-inherited, one female-inherited and eight biparentally inherited markers, we investigate the population genetic structure of the Valais shrew (Sorex antinorii) in the Swiss Alps. Bayesian analysis on autosomal microsatellites suggests a clear genetic differentiation between two groups of populations. This geographically based structure is consistent with two separate postglacial recolonization routes of the species into Switzerland from Italian refugia after the last Pleistocene glaciations. Sex-specific markers also confirm genetic structuring among western and eastern areas, since very few haplotypes for either Y chromosome or mtDNA genome are shared between the two regions. Overall, these results suggest that two already well-differentiated genetic lineages colonized the Swiss Alps and came into secondary contact in the Rhône Valley. Low level of admixture between the two lineages is likely explained by the mountainous landscape structure of lateral valleys orthogonal to the main Rhône valley.

Mature vs. Active Deep-Seated Landslides: A Comparison Through Two Case Histories in the Alps

NASA Astrophysics Data System (ADS)

Delle Piane, Luca; Perello, Paolo; Baietto, Alessandro; Giorza, Alessandra; Musso, Alessia; Gabriele, Piercarlo; Baster, Ira

2016-06-01

Two case histories are presented, concerning the still poorly known alpine deep-seated gravitational slope deformations (DSD) located nearby Lanzada (central Italian Alps), and Sarre (north-western Italian Alps). The Lanzada DSD is a constantly monitored, juvenile, and active phenomenon, partly affecting an existing hydropower plant. Its well-developed landforms allow a precise field characterization of the instability-affected area. The Sarre DSD is a mature, strongly remodeled phenomenon, where the only hazard factor is represented by secondary instability processes at the base of the slope. In this case, the remodeling imposed the adoption of complementary analytical techniques to support the field work. The two presented studies had to be adapted to external factors, namely (a) available information, (b) geological and geomorphological setting, and (c) final scope of the work. The Lanzada case essentially relied upon accurate field work; the Sarre case was mostly based on digital image and DTM processing. In both cases a sound field structural analysis formed the necessary background to understand the mechanisms leading to instability. A back-analysis of the differences between the study methods adopted in the two cases is finally presented, leading to suggestions for further investigations and design.

A Chronologic Dual-Hemisphere Approach to the Last Glacial Termination from the Southern Alps of New Zealand and the Altai Mountains of Western Mongolia

NASA Astrophysics Data System (ADS)

Strand, P.; Putnam, A. E.; Schaefer, J. M.; Denton, G.; Barrell, D.; Putnam, D.; Schwartz, R.; Sambuu, O.; Radue, M. J.; Lindsay, B. J.; Stevens, J.

2017-12-01

Understanding the processes that drove the last glacial termination in the tropics and mid-latitudes is a major unresolved problem in paleoclimate. The most recent glacial to interglacial transition represents the last great global warming and the last time CO2 rose by a substantial amount before the industrial period. Determining the speed of this warming will help refine the global climate system sensitivity to CO2 and will place ongoing global warming into a paleoclimatic context. Here, we test possible drivers of the last glacial termination by comparing chronologies of mountain glaciers, which are highly sensitive to changes in atmospheric temperature, in the middle latitudes of both polar hemispheres. The dating of glacier landforms, such as moraine ridges constructed along glacier margins, affords quantitative insight into past climate conditions. We present 10Be surface-exposure chronologies and glacial geomorphologic maps of mountain glacier recession since the Last Glacial Maximum in the Southern Alps of New Zealand (44°S, 170°E) and in the Altai Mountains of western Mongolia (49°N, 88°E). On the basis of these chronologies from opposing hemispheres, we evaluate the relative roles of rising atmospheric CO2, local insolation forcing, and ocean-atmosphere reorganizations in driving the global warming that ended the last ice age.

Metamorphic sole genesis at the base of ophiolite nappes: Insights from numerical models

NASA Astrophysics Data System (ADS)

Yamato, Philippe; Agard, Philippe; Duretz, Thibault

2015-04-01

Obduction emplaces oceanic lithosphere on top of continental lithosphere. Although a number of studies have focused on this enigmatic process, the initial stages of obduction remain poorly understood. Field, petrological, and geochronological data reveal that during the first stages of the obduction (i.e., during the first 1-2 Myrs) a HT-LP metamorphic sole (~700-800 ° C and ~1 GPa) is systematically welded at the base of ophiolite nappes. However, the reason why such welding of the ophiolite soles occurs at these particular P-T conditions, and only at the onset of obduction, is still an open issue. The aim of this study is to explore the conditions required to explain the genesis of metamorphic soles. For this, we employ two-dimensional numerical modelling, constrained by the wealth of available data from the Oman ophiolite. We first present a thermo-kinematic model in which the velocity field is prescribed in order to simulate obduction initiation. The heat advection-diffusion equation is solved at each time step. The model is intentionally kept simple in order to control each parameter (e.g., convergence rate, dip angle, thermal age) and to test its influence on the resulting P-T conditions obtained through time along the obduction interface. Results show that the key factor allowing the formation of metamorphic soles is the age of the oceanic lithosphere involved. Moreover, we speculate that the reason why metamorphic soles are always welded at the same P-T conditions is due to the fact that, at these particular conditions, strength jumps occur within the oceanic lithosphere. These jumps lead to changes in strain localisation and allow the spalling of oceanic crust and its juxtaposition to the ophiolite nappe. This hypothesis is further tested using thermo-mechanical models in which the obduction initiates dynamically (only initial and boundary conditions are prescribed). The interplay between the temperature evolution and the mechanical behaviour is then

Morphological expression of active tectonics in the Southern Alps

NASA Astrophysics Data System (ADS)

Robl, Jörg; Heberer, Bianca; Neubauer, Franz; Hergarten, Stefan

2015-04-01

rates are not well constrained for the entire domain. Despite of that, extensive karstification in some areas limits the validity of a morphometric analysis in particular of the upper reaches of the drainage system and leads to a long term persistence of landforms (e.g. plateaus). In this study we focus on the drainage pattern of the eastern Southern Alps and the adjacent southern foreland basin. We use a high-resolution digital elevation model and a novel numerical approach to extract characteristic parameters of the morphology for the entire eastern Southern Alps with a high spatial resolution. We explore deviations in the steepness of channels from an equilibrium state and knick-points in longitudinal channel profiles and interpret these features in terms of (a) active tectonics, and variable uplift rates, (b) lithological effects like erodibility contrasts and karstification, and (c) base level lowering caused by glacial erosion and Messinian preconditioning. The drainage system of the Adige shows the most significant deviations from a fluvial equilibrium. This is documented in the normalized steepness index of the main channel and all tributaries as well as in the longitudinal channel profile. The main channel shows several sections of downstream steepening and extremely low channel gradients in the lower reach. Similar deviations are also observed in the Brenta catchment situated east of the Adige drainage system. In contrast to the two large western catchments of the study region, the Piave and particularly the Tagliamento catchment show well graded channel profiles and uniform normalized steepness indices despite of the glacial history. This clear west to east trend from highly disturbed to overall well graded channels has never been documented before and may be explained in the light of increased uplift rates in the east and differences in onset and timing of topography formation between the western and eastern sector of the study region.

Late Maastrichtian foraminiferids and diatoms from the Polish Carpathians (Ropianka Formation, Skole Nappe): a case study from the Chmielnik-Grabówka composite section

NASA Astrophysics Data System (ADS)

Gasiński, M. Adam; Olshtynska, Alexandra; Uchman, Alfred

2013-12-01

Gasiński, M.A., Olshtynska, A. and Uchman, A. 2013. Late Maastrichtian foraminiferids and diatoms from the Polish Carpathians (Ropianka Formation, Skole Nappe): a case study from the Chmielnik-Grabowka composite section. Acta Geologica Polonica, 63(4), 515-525. Warszawa. Well-preserved foraminiferids have been found in the Chmielnik-Grabowka section (Skole Nappe, Polish Carpathians). The Abathomphalus mayaroensis (late Maastrichtian) and Racemiguembelina fructicosa (earlylate Maastrichtian) standard planktonic foraminiferal biozones have been recognized, based on the occurrence of their respective index species. Sediments of the R. fructicosa Zone contain diatoms, which are a rare component of Cretaceous flysch microfossil assemblages in the Carpathians. The diatom frustules and some foraminiferid tests are pyritized, probably after burial in the sediment, below the redox boundary or in the oxygen- deficient microenvironment inside the frustules or tests of microfossils; the presence of trace fossils and bioturbational structures in the same bed indicate an oxygenated sea floor.

Constraints on the Miocene landscape evolution of the Eastern Alps from the Kalkspitze region, Niedere Tauern (Austria)

NASA Astrophysics Data System (ADS)

Dertnig, Florian; Stüwe, Kurt; Woodhead, Jon; Stuart, Finlay M.; Spötl, Christoph

2017-12-01

In order to unravel aspects of the Miocene landscape evolution of the eastern European Alps, we present geomorphic and isotopic data from the western Niedere Tauern region (Austria). The region is critical for such interpretations, because it is one of the few regions along the topographic axis of the Eastern Alps where the highest peaks (up to 2500 m a.s.l.) are dominated by limestone. As such, the region contains a record of Miocene landscape-forming events that survived the Pleistocene glaciations, not preserved elsewhere in the central Eastern Alps. This record includes karst caves, karstified planation surfaces and crystalline fluvial pebbles (Augenstein Formation) preserved on planation surfaces and in karst caves. Caves in the region occur in three distinct levels that correlate with well-known cave levels in the Northern Calcareous Alps, although they are somewhat higher in the Niedere Tauern. In part, these cave elevations also correlate with three planation surfaces and knickpoints of major streams draining the region, testifying their pre-glacial origin. We report details of a karst cave (Durchgangshöhle) from the highest cave level located at 2340 m a.s.l. In this cave, allochthonous fluvial gravels are present, overgrown by speleothems. One speleothem yielded an early middle Pleistocene U-Pb age (682 ± 17 ka). We regard this as a minimum age for the erosion of the fluvial cave deposits during Marine Isotope Stages 17 or 16. Carbon and oxygen isotope data of these speleothems imply a climate that is consistent with this interpretation. Cosmogenic 21Ne data of fluvial quartz clasts collected from the surface on plateaus of the Northern Calcareous Alps suggest minimum exposure durations of 115 and 262 ka. They probably reflect successive exposure since removal of the sediment cover of the Oligocene Augenstein Formation during the Pleistocene. While our geochronological data fail to record aspects of the earlier Miocene uplift history, they are

Nuclear translocation of the cytoskeleton-associated protein, smALP, upon induction of skeletal muscle differentiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cambier, Linda; Pomies, Pascal, E-mail: pascal.pomies@crbm.cnrs.fr

2011-06-17

Highlights: {yields} The cytoskeleton-associated protein, smALP, is expressed in differentiated skeletal muscle. {yields} smALP is translocated from the cytoplasm to the nucleus of C2C12 myoblasts upon induction of myogenesis. {yields} The differentiation-dependent nuclear translocation of smALP occurs in parallel with the nuclear accumulation of myogenin. {yields} The LIM domain of smALP is essential for the nuclear accumulation of the protein. {yields} smALP might act in the nucleus to control some critical aspect of the muscle differentiation process. -- Abstract: The skALP isoform has been shown to play a critical role in actin organization and anchorage within the Z-discs of skeletalmore » muscles, but no data is available on the function of the smALP isoform in skeletal muscle cells. Here, we show that upon induction of differentiation a nuclear translocation of smALP from the cytoplasm to the nucleus of C2C12 myoblasts, concomitant to an up-regulation of the protein expression, occurs in parallel with the nuclear accumulation of myogenin. Moreover, we demonstrate that the LIM domain of smALP is essential for the nuclear translocation of the protein.« less

Climate warming and the recent treeline shift in the European alps: the role of geomorphological factors in high-altitude sites.

PubMed

Leonelli, Giovanni; Pelfini, Manuela; di Cella, Umberto Morra; Garavaglia, Valentina

2011-05-01

Global warming and the stronger regional temperature trends recently recorded over the European Alps have triggered several biological and physical dynamics in high-altitude environments. We defined the present treeline altitude in three valleys of a region in the western Italian Alps and reconstructed the past treeline position for the last three centuries in a nearly undisturbed site by means of a dendrochronological approach. We found that the treeline altitude in this region is mainly controlled by human impacts and geomorphological factors. The reconstruction of the altitudinal dynamics at the study site reveals that the treeline shifted upwards of 115 m over the period 1901-2000, reaching the altitude of 2505 m in 2000 and 2515 m in 2008. The recent treeline shift and the acceleration of tree colonization rates in the alpine belt can be mainly ascribed to the climatic input. However, we point out the increasing role of geomorphological factors in controlling the future treeline position and colonization patterns in high mountains.

Algorithms used in the Airborne Lidar Processing System (ALPS)

USGS Publications Warehouse

Nagle, David B.; Wright, C. Wayne

2016-05-23

The Airborne Lidar Processing System (ALPS) analyzes Experimental Advanced Airborne Research Lidar (EAARL) data—digitized laser-return waveforms, position, and attitude data—to derive point clouds of target surfaces. A full-waveform airborne lidar system, the EAARL seamlessly and simultaneously collects mixed environment data, including submerged, sub-aerial bare earth, and vegetation-covered topographies.ALPS uses three waveform target-detection algorithms to determine target positions within a given waveform: centroid analysis, leading edge detection, and bottom detection using water-column backscatter modeling. The centroid analysis algorithm detects opaque hard surfaces. The leading edge algorithm detects topography beneath vegetation and shallow, submerged topography. The bottom detection algorithm uses water-column backscatter modeling for deeper submerged topography in turbid water.The report describes slant range calculations and explains how ALPS uses laser range and orientation measurements to project measurement points into the Universal Transverse Mercator coordinate system. Parameters used for coordinate transformations in ALPS are described, as are Interactive Data Language-based methods for gridding EAARL point cloud data to derive digital elevation models. Noise reduction in point clouds through use of a random consensus filter is explained, and detailed pseudocode, mathematical equations, and Yorick source code accompany the report.

Significance of the precambrian basement and late Cretaceous thrust nappes on the location of tertiary ore deposits in the Oquirrh Mountains, Utah

USGS Publications Warehouse

Tooker, Edwin W.

2005-01-01

buttress east of the Salt Lake area. The accretion suture along the north flank of the Uinta Anticline overlaps an earlier Precambrian east-west mobile zone, the Uinta trend (Erickson, 1976, Bryant and Nichols, 1988 and John, 1989), which extends westward across western Utah and into Nevada. A trace of the trend underlies the middle part of the Oquirrh Mountains. Its structure is recognized by disrupted Paleozoic stratigraphic units and fold and fault evidence of thrust faulting, intermittent local uplift and erosion, the alignment of Tertiary intrusives and associated ore deposits. Geologic readjustments along the trend continued intermittently through the Paleozoic, Cenozoic, Tertiary, and the development of clastic deposits along the shores of Pleistocene Lake Bonneville. Paleozoic sedimentary rocks were deposited on the craton platform shelf in westernmost Utah and eastern Nevada as the shelf subsided gradually and differentially. Debris was shed into two basins separated by the uplifted Uinta trend, the Oquirrh Basin on the south and Sublette Basin on the north. Sediments were derived from the craton to the east, the Antler orogenic zone on the west (Roberts, 1964), and locally from uplifted parts of the trend itself. Thick accumulations of clastic calcareous quartzite, shale, limestone, and dolomite of Lower and Upper Paleozoic ages are now exposed in the Oquirrh Mountains, the result of thrust faults. Evidence of decollement thrust faults in in the Wasatch Mountains during the Late Cretaceous Sevier orogeny, recognized by Baker and others (1949) and Crittenden (1961, is also recognized in the Oquirrh Mountains by Roberts and others (1965). During the late Cretaceous Sevier Orogeny, nappes were thrust sequentially along different paths from their western hinterland to the foreland. Five distinct nappes converged over the Uinta trend onto an uplifted west-plunging basement buttress east of the Oquirrh Mountains area: the Pass Canyon, Bingham,

Si3 AlP: A New Promising Material for Solar Cell Absorber

NASA Astrophysics Data System (ADS)

Yang, Jihui; Zhai, Yingteng; Liu, Hengrui; Xiang, Hongjun; Gong, Xingao; Wei, Suhuai

2014-03-01

First-principles calculations are performed to study the structural and optoelectronic properties of the newly synthesized nonisovalent and lattice-matched (Si2)0.6(AlP)0.4 alloy [T. Watkins et al., J. Am. Chem. Soc. 2011, 133, 16212.] The most stable structure of Si3AlP is a superlattice along the <111>direction with separated AlP and Si layers, which has a similar optical absorption spectrum to silicon. The ordered C1c1-Si3AlP is found to be the most stable one among all the structures with -AlPSi3- motifs, in agreement with the experimental suggestions. We predict that C1c1-Si3AlP has good optical properties, i.e., it has a larger fundamental band gap and a smaller direct band gap than Si, thus it has much higher absorption in the visible light region, making it a promising candidate for improving the performance of the existing Si-based solar cells.

Alpine Palaeogeography: new constraints from detrital zircon geochronology

NASA Astrophysics Data System (ADS)

Galster, Federico; Stockli, Daniel

2017-04-01

Schardt's (1898) discovery of the "allochtony" of the Préalpes Médianes and its exotic character, provided Alpine geologist with a first picture of Alpine palaeogeography: a Middle Jurassic sea divided in two branches by the rise of an emerged island. Later on, Schardt's island had been recognized at the scale of the Alpine belt and took the name of Briançonnais "geoanticline". In many Alpine palaeogeographic reconstructions, the Briançonnais and its exotic character have played a crucial role (e.g. Stampfli 1993; Manatschal et al., 2006;). In particular some of them explained the exotic character of the Briançonnais facies by proposing a pre-Cretaceous position located far from the Helvetic domain. In this view, the Briançonnais terrain was related to the Iberian plate and entered the Central Alpine system only after a Lower Cretaceous eastward drift associated with anticlockwise rotation of Iberia, opening of the northern Atlantic and closure of the Vardar ocean. In the Central Alps, the remnants of the northern Jurassic margin of the Alpine Tethys (sensu Stampfli) are contained in the Helvetic (s.l.) and Lower Penninic units. The basements and original substrate of these nappes are exposed in the crystalline external massifs and in the gneissic Lepontine dome. The highest, more internal, gneissic units within this dome are the Monte Leone, the Maggia and the Adula nappe. Theses units, as well as the autochthonous basement of the European margin, are characterized by large "Variscan" granitoids with ages between 290 and 330 Ma. The "ophiolite-bearing" units thrust on top of the Adula nappe are composed of Cretaceous and younger sedimentary rocks, with thin soles of Triassic and Jurassic strata. In addition to Variscan, Cambro-Ordovician and Proterozoic ages, detrital zircons in these soles show a peak at 260-280 Ma accompanied by a cluster of ca. 230 Ma zircons, similarly to what is observed in the Schams and Préalpes Médianes nappes (Briançonnais s

10Be exposure dating of the timing of Neoglacial glacier advances in the Ecrins-Pelvoux massif, southern French Alps

NASA Astrophysics Data System (ADS)

Le Roy, Melaine; Deline, Philip; Carcaillet, Julien; Schimmelpfennig, Irene; Ermini, Magali; Aster Team

2017-12-01

Alpine glacier variations are known to be reliable proxies of Holocene climate. Here, we present a terrestrial cosmogenic nuclide (TCN)-based glacier chronology relying on 24 new 10Be exposure ages, which constrain maximum Neoglacial positions of four small to mid-sized glaciers (Rateau, Lautaret, Bonnepierre and Etages) in the Ecrins-Pelvoux massif, southern French Alps. Glacier advances, marked by (mainly lateral) moraine ridges that are located slightly outboard of the Little Ice Age (LIA, c. 1250-1860 AD) maximum positions, were dated to 4.25 ± 0.44 ka, 3.66 ± 0.09 ka, 2.09 ± 0.10 ka, c. 1.31 ± 0.17 ka and to 0.92 ± 0.02 ka. The '4.2 ka advance', albeit constrained by rather scattered dates, is to our knowledge exposure-dated here for the first time in the Alps. It is considered as one of the first major Neoglacial advance in the western Alps, in agreement with other regional paleoclimatological proxies. We further review Alpine and Northern Hemisphere mid-to-high latitude evidence for climate change and glacier activity concomitant with the '4.2 ka event'. The '2.1 ka advance' was not extensively dated in the Alps and is thought to represent a prominent advance in early Roman times. Other Neoglacial advances dated here match the timing of previously described Alpine Neoglacial events. Our results also suggest that a Neoglacial maximum occurred at Etages Glacier 0.9 ka ago, i.e. during the Medieval Climate Anomaly (MCA, c. 850-1250 AD). At Rateau Glacier, discordant results are thought to reflect exhumation and snow cover of the shortest moraine boulders. Overall, this study highlights the need to combine several sites to develop robust Neoglacial glacier chronologies in order to take into account the variability in moraine deposition pattern and landform obliteration and conservation.

Geological history of the Cretaceous ophiolitic complexes of northwestern South America (Colombian Andes)

NASA Astrophysics Data System (ADS)

Bourgois, Jacques; Toussaint, Jean-François; Gonzalez, Humberto; Azema, Jacques; Calle, Bernardo; Desmet, Alain; Murcia, Luis A.; Acevedo, Alvaro P.; Parra, Eduardo; Tournon, Jean

1987-12-01

The Western Cordillera of Colombia was formed by intense alpine-type nappe-forming folding and thrusting. The Cretaceous (80-120 Ma B.P.) tholeiitic material of the Western Cordilleran nappes has been obducted onto the Paleozoic and Precambrian polymetamorphic micaschists and gneiss of the Central Cordillera. Near Yarumal, the Antioquia batholith (60-80 Ma B.P.) intrudes both obducted Cretaceous oceanic material and the polymetamorphic basement rock of the Central Cordillera. Therefore, nappe emplacement and obduction onto the Central Cordillera occurred during Late Senonian to Early Paleocene. The nappes travelled from northwest to southeast so that the highest unit, the Rio Calima nappe therefore has the most northwestern source, whereas the lowest units originated from a more southeastward direction. Sedimentological analysis of the volcanoclastic and sandy turbidite material from each unit suggests a marginal marine environment. During Cretaceous times the opening of this marginal sea, from now on called the "Colombia marginal basin", probably originated by detachment of a block from the South American continent related to the Farallon-South America plate convergence. In the Popayan area (southern Colombia), the Central Cordilleran basement exhibits glaucophane schist facies metamorphism. This high pressure low temperature metamorphism is of Early Cretaceous (125 Ma B.P.) age and is related to an undated metaophiolitic complex. The ophiolitic material originating from the Western Cordilleran is thrust over both the blueschist belt and the metaophiolitic complex. These data suggest that the "Occidente Colombiano" suffered at least two phases of ophiolitic obduction during Mesozoic time.

ALP-RISK, a smartphone app for collecting data on geomorphic phenomena at high altitude in the Mont Blanc region

NASA Astrophysics Data System (ADS)

Ravanel, Ludovic; Deline, Philip

2014-05-01

A network of observers (mountain guides, hut keepers and mountaineers) has been created from 2005 for the Mont Blanc massif in order to acquire data on rockfall in permafrost-affected rock walls. This network, fully operational since 2007, is based on observation sheets or oral communications and has documented nearly 350 events with volume between 100 and 45,000 m3. Their analysis confirmed and helped to better understand the role of the permafrost degradation as main triggering factor. To i) reinforce this network, ii) facilitate its observation work and iii) develop it as well in space (the whole Mont Blanc region, or eventually the whole western Alps) as in a thematic point of view (all glacial and periglacial brutal phenomena), the Alp-Risk app has been created in the framework of the Alcotra PrévRisk Mont-Blanc project. The latter (2011-13) has been developed to improve the prevention of individual and collective natural hazards around the Mont Blanc massif. The app was created for I-Phones and Androids in three languages (French, English and Italian) and allows, as intuitively and quickly as possible, transmitting data on natural hazards in high mountain (snow and ice avalanche, landslides and rockfalls, landslides, moraine destabilization, water pocket outburst flood, torrential flood, and others) to both practitioners (observations available directly on the app via an interface web), scientists, and possibly local managers. Alp-Risk thus constitutes a new step for participatory science in the Mont Blanc region.

Thermochronometry across the Austroalpine-Pennine boundary, Central Alps, Switzerland: Orogen-perpendicular normal fault slip on a major ‘overthrust’ and its implications for orogenesis

USGS Publications Warehouse

Price, Jason B.; Wernicke, Brian P.; Cosca, Michael A.; Farley, Kenneth A.

2018-01-01

Fifty‐one new and 309 published thermochronometric ages (nine systems with closure temperatures ranging from ~450 to 70°C) from the Graubünden region of the Central Alps demonstrate that a pronounced thermal mismatch between the Austroalpine allochthon (Alpine “orogenic lid”) and the Pennine zone persisted until at least 29 Ma and, allowably, until circa 18 Ma. The observed mismatch supports previous suggestions that the famous “overthrust” between the Austroalpine allochthon and the Pennine zone, historically regarded as primarily an Eocene top‐north thrust fault, is in fact primarily an Oligocene‐Miocene normal fault that has a minimum of 60 km of displacement with top‐south or top‐southeast sense of shear. Two hallmarks of Alpine geology, deposition of the foredeep Molasse and emplacement of the Helvetic nappes, appear to be coeval, peripheral manifestations of crustal thickening via the interposition of the Pennine zone as a northward intruding wedge between the Austroalpine “lid” and the European cratonic margin, with the Helvetic system (European margin) acting as the “floor” of the wedge. We presume the Penninic wedge is driven by the buoyant rise of subducted crust no longer able to remain attached to the descending slab. If so, emplacement of the Pennine wedge could have occurred mainly after Adria was juxtaposed against cratonic Europe.

From Permo-Triassic lithospheric thinning to Jurassic rifting at the Adriatic margin: Petrological and geochronological record in Valtournenche (Western Italian Alps)

NASA Astrophysics Data System (ADS)

Manzotti, Paola; Rubatto, Daniela; Darling, James; Zucali, Michele; Cenki-Tok, Bénédicte; Engi, Martin

2012-08-01

Slices of polycyclic metasediments (marbles and meta-cherts) are tectonically amalgamated with the polydeformed basement of the Dent Blanche tectonic system along a major Alpine shear zone in the Western Alps (Becca di Salé area, Valtournenche Valley). A combination of techniques (structural analysis at various scales, metamorphic petrology, geochronology and trace element geochemistry) was applied to determine the age and composition of accessory phases (titanite, allanite and zircon) and their relation to major minerals. The results are used to reconstruct the polyphase structural and metamorphic histories, comprising both pre-Alpine and Alpine cycles. The pre-Alpine evolution is associated with low-pressure high-temperature metamorphism related to Permo-Triassic lithospheric thinning. In meta-cherts, microtextural relations indicate coeval growth of allanite and garnet during this stage, at ~ 300 Ma. Textures of zircon also indicate crystallisation at HT conditions; ages scatter from 263 to 294 Ma, with a major cluster of data at ~ 276 Ma. In impure marble, U-Pb analyses of titanite domains (with variable Al and F contents) yield apparent 206Pb/238U dates range from Permian to Jurassic. Chemical and isotopic data suggest that titanite formed at Permian times and was then affected by (extension-related?) fluid circulation during the Triassic and Jurassic, which redistributed major elements (Al and F) and partially opened the U-Pb system. The Alpine cycle lead to early blueschist facies assemblages, which were partly overprinted under greenschist facies conditions. The strong Alpine compressional overprint disrupted the pre-Alpine structural imprint and/or reactivated earlier structures. The pre-Alpine metamorphic record, preserved in these slices of metasediments, reflects the onset of the Permo-Triassic lithospheric extension to Jurassic rifting.

Probabilistic Seismic Risk Model for Western Balkans

NASA Astrophysics Data System (ADS)

Stejskal, Vladimir; Lorenzo, Francisco; Pousse, Guillaume; Radovanovic, Slavica; Pekevski, Lazo; Dojcinovski, Dragi; Lokin, Petar; Petronijevic, Mira; Sipka, Vesna

2010-05-01

A probabilistic seismic risk model for insurance and reinsurance purposes is presented for an area of Western Balkans, covering former Yugoslavia and Albania. This territory experienced many severe earthquakes during past centuries producing significant damage to many population centres in the region. The highest hazard is related to external Dinarides, namely to the collision zone of the Adriatic plate. The model is based on a unified catalogue for the region and a seismic source model consisting of more than 30 zones covering all the three main structural units - Southern Alps, Dinarides and the south-western margin of the Pannonian Basin. A probabilistic methodology using Monte Carlo simulation was applied to generate the hazard component of the model. Unique set of damage functions based on both loss experience and engineering assessments is used to convert the modelled ground motion severity into the monetary loss.

Strain partitioning in the footwall of the Somiedo Nappe: structural evolution of the Narcea Tectonic Window, NW Spain

NASA Astrophysics Data System (ADS)

Gutiérrez-Alonso, Gabriel

1996-10-01

The Somiedo Nappe is a major thrust unit in the Cantabrian Zone, the external foreland fold and thrust belt of the North Iberian Variscan orogen. Exposed at the Narcea Tectonic Window are Precambrian rocks below the basal decollement of the Somiedo Nappe, which exhibit a different deformation style than the overlying Paleozoic rocks above the basal decollement. During Variscan deformation, folding and widespread subhorizontal, bedding-parallel decollements were produced in the hanging wall within the Paleozoic rocks. Vertical folding, with related axial-planar cleavage at a high angle to the decollement planes, developed simultaneously in the upper Proterozoic Narcea Slates of the footwall, below the detachment. The relative magnitude of finite strain, measured in the footwall rocks, diminishes towards the foreland. These observations indicate that (1) significant deformation may occur in the footwall of foreland fold and thrust belts, (2) the shortening mechanism in the footwall may be different from that of the hanging wall, and (3) in this particular case, the partitioning of the deformation implies the existence of a deeper, blind decollement surface contemporaneous with the first stages of the foreland development, that does not crop out in the region. This implies a significant shortening in the footwall, which must be taken into account when restoration and balancing of cross-sections is attempted. A sequential diagram of the evolution of the Narcea Tectonic Window with a minimum shortening of 85 km is proposed, explaining the complete Variscan evolution of the foreland to hinterland transition in the North Iberian Variscan orogen.

Tourmaline's record of Alpine metamorphism and segregation formation in the Pfitsch Formation, Western Tauern Window

NASA Astrophysics Data System (ADS)

Berryman, E. J.; Kutzschbach, M.; Trumbull, R. B.; Meixner, A.; van Hinsberg, V.; Kasemann, S.; Franz, G.

2017-12-01

Tourmaline, a common accessory mineral in the metasedimentary units of the Pfitsch Formation in the Western Tauern Window, Eastern Alps, records the variation in fluid composition and B mobilization during Alpine metamorphism. These post-Variscan metasediments are part of the Subpenninic nappes, the former European distal margin, and experienced peak metamorphic conditions of 550°C, 1.0 GPa. In all investigated units, tourmaline is predominantly dravitic, with high Fe contents. Charge balance calculations combined with Fe-Mg and Fe-Al variation suggest a significant proportion of ferric iron. Tourmaline's composition reflects its host rock assemblage, with the relative predominance of Fe-Mg or Fe-Al exchange in tourmaline from different units corresponding to the presence of biotite/chlorite or muscovite, respectively. Boron content and correspondingly tourmaline abundance is highest in a 25 m thick unit of feldspathic gneiss ( 20-200 ppm B). The abundance and size of the tourmaline crystals increases near coarse-grained quartzofeldspathic segregations ( 1200 ppm B), reflecting the mobilization and concentration of B by the metamorphic fluid. Tourmaline crystals near segregations have up to three growth zones, recording pro- ( 350-500°C, 0.7-1.0 GPa) and retrograde (400°C, 0.2 GPa) growth. They show the largest amount of compositional variation, covering the range of compositional space represented by tourmaline occurring away from segregations. Tourmaline near segregations has the highest inferred ferric iron content, which decreases across growth zones, potentially reflecting the gradual reduction of the fluid during metamorphism. Whole rock δ11B values (-15 to -34‰) vary with the heaviest values found near B-rich segregations, and the lightest values in B-depleted samples. This correlation reflects the preferential mobilization of 11B towards the segregations. Isotopic zonation of individual tourmaline crystals with -11‰ in their cores and -20‰ in

Assessment and selection of geomorphosites and trails in the Miage Glacier area (Western Italian alps).

PubMed

Bollati, Irene; Smiraglia, Claudio; Pelfini, Manuela

2013-04-01

Glacial environments are considered geomorphosites because they exhibit all of the features that characterise sites of geomorphological interest. The Miage Glacier, in particular, is the most important debris-covered glacier of the Italian Alps, and it has been extensively studied since the 18th century because of its scientific features. In this area, the geomorphological and geological attributes are evaluated at 11 sites that have been individuated along the three main touristic trails, which allow an exploration of the surroundings of the glacial tongue and its two main lobes. Using a methodology previously tested in a fluvial environment, single sites and trails are quantitatively assessed to determine the most suitable trail for educational purposes. Hazards that could potentially affect the trails are considered in terms of both risk education and final selection of the most suitable trails for the various possible user groups. The richness of scientific data in this area should increase its importance as a geomorphosite by increasing the educational value of the Miage Glacier and the Veny Valley.

Assessment and Selection of Geomorphosites and Trails in the Miage Glacier Area (Western Italian Alps)

NASA Astrophysics Data System (ADS)

Bollati, Irene; Smiraglia, Claudio; Pelfini, Manuela

2013-04-01

Glacial environments are considered geomorphosites because they exhibit all of the features that characterise sites of geomorphological interest. The Miage Glacier, in particular, is the most important debris-covered glacier of the Italian Alps, and it has been extensively studied since the 18th century because of its scientific features. In this area, the geomorphological and geological attributes are evaluated at 11 sites that have been individuated along the three main touristic trails, which allow an exploration of the surroundings of the glacial tongue and its two main lobes. Using a methodology previously tested in a fluvial environment, single sites and trails are quantitatively assessed to determine the most suitable trail for educational purposes. Hazards that could potentially affect the trails are considered in terms of both risk education and final selection of the most suitable trails for the various possible user groups. The richness of scientific data in this area should increase its importance as a geomorphosite by increasing the educational value of the Miage Glacier and the Veny Valley.

Contrasting cooling and exhumation histories of tectonic blocks in the eastern part of the Eastern Alps and its possible relationships with lithospheric dynamics

NASA Astrophysics Data System (ADS)

Wölfler, Andreas; Glotzbach, Christoph

2017-04-01

In the European Alps two fundamental changes in the lithospheric structure controlled the geodynamic evolution of the orogen: (1) Late Eocene to Early Oligocene rupturing of the European slab and (2) Early Miocene change in subduction polarity between the Western and Eastern Alps. In particular, the eastern part of the Eastern Alps is a key area which will provide both, information about the surface response to the Eocene/Oligocene slab breakoff and the response to a proposed isostatic rebound due to slab detachment of the European lithosphere in the Miocene (Handy et al., 2015). The eastern part of the Eastern Alps is characterized by fault-bounded blocks with different thermochronological ages, mean elevations and hillslope angles, indicating a variable spatial and temporal evolution throughout the Cenozoic era. The topographic pattern of the study area can be described in terms of (1) high relief with a rugged surface and steep slopes in the Niedere Tauern and (2) lower relief and distinctly smoother topography in the Seckauer Tauern, the Gurktal, Saualpe and Koralpe blocks. Generally, tectonic blocks with higher relief and rugged topography display the youngest apatite fission track (AFT) and apatite (U-Th)/He data (AHe); the Niedere Tauern concurs with middle Miocene AFT and late Miocene/Pliocene AHe ages (Wölfler et al., 2016). The other tectonic blocks generally show Eocene to Oligocene AFT ages (Wölfler et al., 2016 and references therein) and Oligocene to early Miocene AHe ages (Legrain et al., 2014, own preliminary work). New AFT and AHe data from the Gurktal block and Seckauer Tauern indicate that substantial parts of the study area where at near-surface conditions since the Eocene and Oligocene. Thermal history models suggest fast cooling through the AFT and AHe closure temperatures in the Oligocene as a possible response to slab breakoff that was followed by thermal stagnation until the present. In contrast, the neighboring Niedere Tauern experienced

Regulation of the Synthesis of the Angucyclinone Antibiotic Alpomycin in Streptomyces ambofaciens by the Autoregulator Receptor AlpZ and Its Specific Ligand▿

PubMed Central

Bunet, Robert; Mendes, Marta V.; Rouhier, Nicolas; Pang, Xiuhua; Hotel, Laurence; Leblond, Pierre; Aigle, Bertrand

2008-01-01

Streptomyces ambofaciens produces an orange pigment and the antibiotic alpomycin, both of which are products of a type II polyketide synthase gene cluster identified in each of the terminal inverted repeats of the linear chromosome. Five regulatory genes encoding Streptomyces antibiotic regulatory proteins (alpV, previously shown to be an essential activator gene; alpT; and alpU) and TetR family receptors (alpZ and alpW) were detected in this cluster. Here, we demonstrate that AlpZ, which shows high similarity to γ-butyrolactone receptors, is at the top of a pathway-specific regulatory hierarchy that prevents synthesis of the alp polyketide products. Deletion of the two copies of alpZ resulted in the precocious production of both alpomycin and the orange pigment, suggesting a repressor role for AlpZ. Consistent with this, expression of the five alp-located regulatory genes and of two representative biosynthetic structural genes (alpA and alpR) was induced earlier in the alpZ deletion strain. Furthermore, recombinant AlpZ was shown to bind to specific DNA sequences within the promoter regions of alpZ, alpV, and alpXW, suggesting direct transcriptional control of these genes by AlpZ. Analysis of solvent extracts of S. ambofaciens cultures identified the existence of a factor which induces precocious production of alpomycin and pigment in the wild-type strain and which can disrupt the binding of AlpZ to its DNA targets. This activity is reminiscent of γ-butyrolactone-type molecules. However, the AlpZ-interacting molecule(s) was shown to be resistant to an alkali treatment capable of inactivating γ-butyrolactones, suggesting that the AlpZ ligand(s) does not possess a lactone functional group. PMID:18296523

Regulation of the synthesis of the angucyclinone antibiotic alpomycin in Streptomyces ambofaciens by the autoregulator receptor AlpZ and its specific ligand.

PubMed

Bunet, Robert; Mendes, Marta V; Rouhier, Nicolas; Pang, Xiuhua; Hotel, Laurence; Leblond, Pierre; Aigle, Bertrand

2008-05-01

Streptomyces ambofaciens produces an orange pigment and the antibiotic alpomycin, both of which are products of a type II polyketide synthase gene cluster identified in each of the terminal inverted repeats of the linear chromosome. Five regulatory genes encoding Streptomyces antibiotic regulatory proteins (alpV, previously shown to be an essential activator gene; alpT; and alpU) and TetR family receptors (alpZ and alpW) were detected in this cluster. Here, we demonstrate that AlpZ, which shows high similarity to gamma-butyrolactone receptors, is at the top of a pathway-specific regulatory hierarchy that prevents synthesis of the alp polyketide products. Deletion of the two copies of alpZ resulted in the precocious production of both alpomycin and the orange pigment, suggesting a repressor role for AlpZ. Consistent with this, expression of the five alp-located regulatory genes and of two representative biosynthetic structural genes (alpA and alpR) was induced earlier in the alpZ deletion strain. Furthermore, recombinant AlpZ was shown to bind to specific DNA sequences within the promoter regions of alpZ, alpV, and alpXW, suggesting direct transcriptional control of these genes by AlpZ. Analysis of solvent extracts of S. ambofaciens cultures identified the existence of a factor which induces precocious production of alpomycin and pigment in the wild-type strain and which can disrupt the binding of AlpZ to its DNA targets. This activity is reminiscent of gamma-butyrolactone-type molecules. However, the AlpZ-interacting molecule(s) was shown to be resistant to an alkali treatment capable of inactivating gamma-butyrolactones, suggesting that the AlpZ ligand(s) does not possess a lactone functional group.

The rising greenhouse effect: experiments and observations in and around the Alps

NASA Astrophysics Data System (ADS)

Philipona, R.

2010-09-01

The rapid temperature increase of more than 1°C in central Europe over the last three decades is larger than expected from anthropogenic greenhouse warming. Surface radiation flux measurements in and around the Alps in fact confirm that not only thermal longwave radiation but also solar shortwave radiation increased since the 1980s. Surface energy budget analyses reveal the rising surface temperature to be well correlated with the radiative forcing, and also show an increase of the kinetic energy fluxes explaining the rise of atmospheric water vapor. Solar radiation mainly increased due to a strong decline of anthropogenic aerosols since mid of the 1980s. While anthropogenic aerosols were mainly accumulated in the boundary layer, this reduction let solar radiation to recover (solar brightening after several decades of solar dimming) mainly at low altitudes around the Alps. At high elevations in the Alps, solar forcing is much smaller and the respective temperature rise is also found to be smaller than in the lowlands. The fact that temperature increases less in the Alps than at low elevations is unexpected in the concept of greenhouse warming, but the radiation budget analyses clearly shows that in the plains solar forcing due to declining aerosols additionally increased surface temperature, whereas in the Alps temperature increased primarily due to greenhouse warming that is particularly manifested by a strong water vapor feedback.

Evidence for ongoing extensional deformation in the western Swiss Alps and thrust-faulting in the southwestern Alpine foreland

NASA Astrophysics Data System (ADS)

Eva, Elena; Pastore, Stefania; Deichmann, Nicholas

1998-09-01

To verify the discordant orientations of P- and T-axes found by earlier studies in the Penninic domain of the southern Valais, Switzerland, and in the surrounding regions of France and Italy, we have evaluated the focal mechanisms of 11 of the best-recorded earthquakes that occurred in this area between 1985 and 1990. By employing two-dimensional ray-tracing techniques, we have made use of what is known about the lateral variations of the crustal structure to obtain constraints on the possible focal-depth range of the hypocenters and on the take-off angles at the source. In addition, we have been able to identify one of the two nodal planes as the actual fault plane of one of the events, based on high-resolution relative locations of its aftershocks. The resulting normal faulting and oblique-slip focal mechanisms show that, down to depths of about 10 km, the compressional structures of the Penninic nappes, which were formed during the Alpine orogeny, are presently undergoing extensional deformation and that a significant component of this extension is perpendicular to the Alpine arc. Thrust faulting focal mechanisms from events at the northwestern margin of the Po plain, however, indicate that the southern Alpine foreland is still subject to compressional deformation consistent with the large-scale stress field expected from the convergence of the African and European plates. Thus, our results lend support to geodynamic models that predict extensional deformation across the crest of a mountain range, while the flanks and lowlands continue to undergo crustal shortening.

Photometric transit search for planets around cool stars from the western Italian Alps: a pilot study

NASA Astrophysics Data System (ADS)

Giacobbe, P.; Damasso, M.; Sozzetti, A.; Toso, G.; Perdoncin, M.; Calcidese, P.; Bernagozzi, A.; Bertolini, E.; Lattanzi, M. G.; Smart, R. L.

2012-08-01

We present the results of a year-long photometric monitoring campaign of a sample of 23 nearby (d < 60 pc), bright (J < 12) dM stars carried out at the Astronomical Observatory of the Autonomous Region of the Aosta Valley, in the western Italian Alps. This programme represents a 'pilot study' for a long-term photometric transit search for planets around a large sample of nearby M dwarfs, due to start with an array of identical 40-cm class telescopes by the Spring of 2012. In this study, we set out to (i) demonstrate the sensitivity to <4 R⊕ transiting planets with periods of a few days around our programme stars, through a two-fold approach that combines a characterization of the statistical noise properties of our photometry with the determination of transit detection probabilities via simulations; and (ii) where possible, improve our knowledge of some astrophysical properties (e.g. activity, rotation) of our targets by combining spectroscopic information and our differential photometric measurements. We achieve a typical nightly root mean square (RMS) photometric precision of ˜5 mmag, with little or no dependence on the instrumentation used or on the details of the adopted methods for differential photometry. The presence of correlated (red) noise in our data degrades the precision by a factor of ˜1.3 with respect to a pure white noise regime. Based on a detailed stellar variability analysis (i) we detected no transit-like events (an expected result, given the sample size); (ii) we determined photometric rotation periods of ˜0.47 and ˜0.22 d for LHS 3445 and GJ 1167A, respectively; (iii) these values agree with the large projected rotational velocities (˜25 and ˜33 km s-1, respectively) inferred for both stars based on the analysis of archival spectra; (iv) the estimated inclinations of the stellar rotation axes for LHS 3445 and GJ 1167A are consistent with those derived using a simple spot model; and (v) short-term, low-amplitude flaring events were

Climate change impacts on mass movements--case studies from the European Alps.

PubMed

Stoffel, M; Tiranti, D; Huggel, C

2014-09-15

This paper addresses the current knowledge on climate change impacts on mass movement activity in mountain environments by illustrating characteristic cases of debris flows, rock slope failures and landslides from the French, Italian, and Swiss Alps. It is expected that events are likely to occur less frequently during summer, whereas the anticipated increase of rainfall in spring and fall could likely alter debris-flow activity during the shoulder seasons (March, April, November, and December). The magnitude of debris flows could become larger due to larger amounts of sediment delivered to the channels and as a result of the predicted increase in heavy precipitation events. At the same time, however, debris-flow volumes in high-mountain areas will depend chiefly on the stability and/or movement rates of permafrost bodies, and destabilized rock glaciers could lead to debris flows without historic precedents in the future. The frequency of rock slope failures is likely to increase, as excessively warm air temperatures, glacier shrinkage, as well as permafrost warming and thawing will affect and reduce rock slope stability in the direction that adversely affects rock slope stability. Changes in landslide activity in the French and Western Italian Alps will likely depend on differences in elevation. Above 1500 m asl, the projected decrease in snow season duration in future winters and springs will likely affect the frequency, number and seasonality of landslide reactivations. In Piemonte, for instance, 21st century landslides have been demonstrated to occur more frequently in early spring and to be triggered by moderate rainfalls, but also to occur in smaller numbers. On the contrary, and in line with recent observations, events in autumn, characterized by a large spatial density of landslide occurrences might become more scarce in the Piemonte region. Copyright © 2014 Elsevier B.V. All rights reserved.

Evolution of quartz microstructure and c-axis crystallographic preferred orientation within ductilely deformed granitoids (Arolla unit, Western Alps)

NASA Astrophysics Data System (ADS)

Menegon, Luca; Pennacchioni, Giorgio; Heilbronner, Renee; Pittarello, Lidia

2008-11-01

We have studied quartz microstructures and the c-axis crystallographic preferred orientations (CPOs) in four granitoid samples representative of increasing ductile shear deformation, from a weakly deformed granitoid (stage 1) to a mylonitic granitoid (stage 4). The quartz c-axis CPO measured in the mylonitic granitoid has been compared with the one observed in a fully recrystallized quartz mylonite from the same area. All the samples belong to the Austroalpine Arolla unit (Western Alps) and were deformed at greenschist facies conditions. The quartz c-axis CPO was analyzed using a U-stage and the optical orientation imaging technique. The magmatic plagioclase, forming more than 50% of the volume of the granitoid, is extensively replaced by a mica-rich aggregate even in weakly deformed samples of stage 1. These aggregates flow to form an interconnected weak matrix with increasing deformation, wrapping relatively less strained quartz grains that undergo dominantly coaxial strain. Recrystallization of quartz ranges from less than 1% in the weakly deformed granitoid to up to 85% in the mylonitic granitoid, with average grain strain of 41% and 64%, respectively. With increasing strain and recrystallization, quartz grains in the granitoids show a sequence of transient microstructures and CPOs. Crystal plastic deformation is initially accomplished by dislocation glide with limited recovery, and at 50% grain strain it results in a CPO consistent with dominantly basal < a> slip. At 60% grain strain, recrystallization is preferentially localized along shear bands, which appear to develop along former intragranular cracks, and the recrystallized grains develop a strong c-axis CPO with maxima orthogonal to the shear band boundaries and independent of the host grain orientation. Within the granitoid mylonite, at an average quartz grain strain of 64%, recrystallization is extensive and the c-axis CPO of new grains displays maxima overlapping the host c-axis orientation and

Climbing walls as multitasking sites of geo(morpho)logical interests: Italian examples from the Western Alps and Sardinia

NASA Astrophysics Data System (ADS)

Bollati, Irene; Fossati, Maria; Panizza, Valeria; Pelfini, Manuela; Zanoletti, Enrico; Zucali, Michele

2015-04-01

Geosites and in particular geomorphosites have been recently more and more used as base for educational activities in Earth Sciences and to enhance the geodiversity of a territory. Their attributes acquire a greater value and become especially appreciable when associated with field and outdoor activities. Frequently rock walls represent key sites for geological and gemorphological researches due to the wide outcrops of rocks where mineralogical composition and structures are very evident as well as landforms deriving from the modeling of outcrops surfaces. Where the rock walls are equipped for climbing activities they may be considered open-air laboratories useful to get in touch with the different features of rocks that condition progression on climbing routes. Due to these two aspects, geohistorical importance and educational exemplarity contribute to the increase of the scientific value and, as a consequence, of the global value of these sites as geosites. Geomorphosites from climbing sites allow to realize educational projects with different goals: 1) Recent researches in the Western Italian Alps have been conducted to make a census of climbing rock cliffs along the Ossola Valley (Verbanio-Cusio-Ossola Province, Italy) and to operate a choice of the ones characterized by high educational value (considering easy accessibility, grades for experts and beginners and the good exposition of rock features), representativeness, geohistorical importance, high cultural and socio-economic values, in order to propose an educational project addressed to students of an Italian secondary school aimed at introducing the three great families of rocks (magmatic, metamorphic and sedimentary); 2) The Eclogitic Micaschist Complex of the Austroalpine Domain (Montestrutto climbing wall, Turin Province, Italy) has been investigated in order to i) reconstruct the deformation stages at local scales along the sport climbing wall and the relationships between geological elements and

The AlpArray Seismic Network: current status and next steps

NASA Astrophysics Data System (ADS)

Hetényi, György; Molinari, Irene; Clinton, John; Kissling, Edi

2016-04-01

The AlpArray initiative (http://www.alparray.ethz.ch) is a large-scale European collaboration to study the entire Alpine orogen at high resolution and in 3D with a large variety of geoscientific methods. The core element of the initiative is an extensive and dense broadband seismological network, the AlpArray Seismic Network (AASN), which complements the permanent seismological stations to ensure homogeneous coverage of the greater Alpine area. The some 260 temporary stations of the AlpArray Seismic Network are operated as a joint effort by a number of institutions from Austria, Bosnia-Herzegovina, Croatia, Czech Republic, France, Germany, Hungary, Italy, Slovakia and Switzerland. The first stations were installed in Spring 2015 and the full AASN is planned to be operational by early Summer 2016. In this poster we present the actual status of the deployment, the effort undertaken by the contributing groups, station performance, typical noise levels, best practices in installation as well as in data management, often encountered challenges, and planned next steps including the deployment of ocean bottom seismometers in the Ligurian Sea.

Authigenic potassium feldspar: a tracer for the timing of palaeofluid flow in carbonate rocks, Northern Calcareous Alps, Austria

USGS Publications Warehouse

Spotl, C.; Kunk, Michael J.; Ramseyer, K.; Longstaffe, F.J.

1998-01-01

This paper is included in the Special Publication entitled 'Dating and duration of fluid flow and fluid-rock interaction', edited by J. Parnell. Feldspar is a common authigenic constituent in Permian carbonate rocks which occur as tectonically isolated blocks within the evaporitic Haselgebirge melange in the Northern Calcareous Alps (NCA). Coexisting with pyrite, anhydrite, (saddle) dolomite, magnesite, fluorite and calcite, K-feldspar and minor albite record an event of regionally extensive interaction of hot brines with carbonate rocks. Detailed petrographic, crystallographic and geochemical studies reveal a variability in crystal size and shape, Al-Si ordering, elemental and stable isotopic compositions of the K-feldspar, which is only partially consistent with the traditional view of authigenic feldspar as a well-ordered, compositionally pure mineral. 40Ar-39Ar step- heating measurements of authigenic potassium feldspar from several localities yield two age populations, an older one of 145-154 Ma, and a younger one of c.90-97 Ma. Most age spectra reflect cooling through the argon retention temperature interval, which was rapid in some localities (as indicated by plateau ages) and slower in others. Rb-Sr isotope data are more difficult to interpret, because in many K-feldspar samples they are controlled largely by Sr-bearing inclusions. The Jurassic 40Ar-39Ar dates are interpreted as minimum ages of feldspar growth and hence imply that fluid-rock interaction is likely to be simultaneous with or to slightly predate melange formation. Deformation associated with the closure and subduction of the Meliata-Hallstatt ocean south of the NCA during the Upper Jurassic is regarded as the principal geodynamic driving force for both enhanced fluid circulation and melange formation. Some localities were reheated beyond the argon retention temperature for microcline during mid-Cretaceous nappe stacking of the NCA, thus obliterating the older signal.

Glacial isostatic uplift of the European Alps

PubMed Central

Mey, Jürgen; Scherler, Dirk; Wickert, Andrew D.; Egholm, David L.; Tesauro, Magdala; Schildgen, Taylor F.; Strecker, Manfred R.

2016-01-01

Following the last glacial maximum (LGM), the demise of continental ice sheets induced crustal rebound in tectonically stable regions of North America and Scandinavia that is still ongoing. Unlike the ice sheets, the Alpine ice cap developed in an orogen where the measured uplift is potentially attributed to tectonic shortening, lithospheric delamination and unloading due to deglaciation and erosion. Here we show that ∼90% of the geodetically measured rock uplift in the Alps can be explained by the Earth’s viscoelastic response to LGM deglaciation. We modelled rock uplift by reconstructing the Alpine ice cap, while accounting for postglacial erosion, sediment deposition and spatial variations in lithospheric rigidity. Clusters of excessive uplift in the Rhône Valley and in the Eastern Alps delineate regions potentially affected by mantle processes, crustal heterogeneity and active tectonics. Our study shows that even small LGM ice caps can dominate present-day rock uplift in tectonically active regions. PMID:27830704

Glacial isostatic uplift of the European Alps.

PubMed

Mey, Jürgen; Scherler, Dirk; Wickert, Andrew D; Egholm, David L; Tesauro, Magdala; Schildgen, Taylor F; Strecker, Manfred R

2016-11-10

Following the last glacial maximum (LGM), the demise of continental ice sheets induced crustal rebound in tectonically stable regions of North America and Scandinavia that is still ongoing. Unlike the ice sheets, the Alpine ice cap developed in an orogen where the measured uplift is potentially attributed to tectonic shortening, lithospheric delamination and unloading due to deglaciation and erosion. Here we show that ∼90% of the geodetically measured rock uplift in the Alps can be explained by the Earth's viscoelastic response to LGM deglaciation. We modelled rock uplift by reconstructing the Alpine ice cap, while accounting for postglacial erosion, sediment deposition and spatial variations in lithospheric rigidity. Clusters of excessive uplift in the Rhône Valley and in the Eastern Alps delineate regions potentially affected by mantle processes, crustal heterogeneity and active tectonics. Our study shows that even small LGM ice caps can dominate present-day rock uplift in tectonically active regions.

ATM Coastal Topography-Florida 2001: Western Panhandle

USGS Publications Warehouse

Yates, Xan; Nayegandhi, Amar; Brock, John C.; Sallenger, A.H.; Bonisteel, Jamie M.; Klipp, Emily S.; Wright, C. Wayne

2009-01-01

These remotely sensed, geographically referenced elevation measurements of Lidar-derived first surface (FS) topography were produced collaboratively by the U.S. Geological Survey (USGS), Florida Integrated Science Center (FISC), St. Petersburg, FL, and the National Aeronautics and Space Administration (NASA), Wallops Flight Facility, VA. This project provides highly detailed and accurate datasets of the western Florida panhandle coastline, acquired October 2-4 and 7-10, 2001. The datasets are made available for use as a management tool to research scientists and natural resource managers. An innovative scanning Lidar instrument originally developed by NASA, and known as the Airborne Topographic Mapper (ATM), was used during data acquisition. The ATM system is a scanning Lidar system that measures high-resolution topography of the land surface and incorporates a green-wavelength laser operating at pulse rates of 2 to 10 kilohertz. Measurements from the laser-ranging device are coupled with data acquired from inertial navigation system (INS) attitude sensors and differentially corrected global positioning system (GPS) receivers to measure topography of the surface at accuracies of +/-15 centimeters. The nominal ATM platform is a Twin Otter or P-3 Orion aircraft, but the instrument may be deployed on a range of light aircraft. Elevation measurements were collected over the survey area using the ATM system, and the resulting data were then processed using the Airborne Lidar Processing System (ALPS), a custom-built processing system developed in a NASA-USGS collaboration. ALPS supports the exploration and processing of Lidar data in an interactive or batch mode. Modules for presurvey flight line definition, flight path plotting, Lidar raster and waveform investigation, and digital camera image playback have been developed. Processing algorithms have been developed to extract the range to the first and last significant return within each waveform. ALPS is routinely used

Fi Investigations On Hp-Rocks From The Lower Engadine Window New Insights On Its Late Tectono-Metamorphic Evolution

NASA Astrophysics Data System (ADS)

Bertle, R. J.; Götzinger, M. A.; Koller, F.

2003-04-01

Fluid inclusions studies in metamorphic rocks allow to reconstruct not only the chemistry of the fluids enabling and/or supporting metamorphic reactions but also the late metamorphic evolution of orogenesis. Therefore late, discordant quarz-calcite veins were investigated using FI-techniques. The Engadine Window which is exposed at the Swiss-Austrian-border exposes the penninic units of the Western Alps as a tectonic window within the Austroalpine nappes of the Eastern Alps. The nappes of the Engadine window underwent metamorphism and deformation during Tertiary times (THÖNI 1981, BERTLE 2000). The highest unit (Fimber unit) and the core of the window (= Zone of Pfunds) suffered HP-LT-metamorphism. P-T-conditions for parts of the Zone of Pfunds at the region of Piz Mundin are at 13-15 kbar at 380^oC (BOUSQUET et al. 2002) indicated by the occurrence of carpholite and glaucophane. The late metamorphic history is not very well constrained. There exist only a few FI-data published in an abstract by STÖCKHERT et al. 1990 and some unpublished data in RING 1989. During the ongoing mapping campaign of the first author samples from the Fimber unit and the Zone of Pfunds were collected and investigated using a LINKHAM freezing-cooling-stage. The investigated veins are discordant in respect to the main-foliation of the rocks and show nice cristalls of quarz, calcite and sometimes feldspar (adularia). Structural data implie that the investigated veins correspond to a set of ac-joints that correlate to the late updoming of the large "Engadiner Gewölbe" (Engadin anticlinal structure, MATTMÜLLER 1996). All investigated veins (from all tectonic units) show the same relationship to the anticlinal structure. FI-investigations show, that a large amount of the primary FI are decrepitated, however it was possible to find enough to provide a serious statistical data set. FI from Piz Mundin in the core of the Engadine window exhibit at the base of the vein quarz at the contact to

Changes of forest cover and disturbance regimes in the mountain forests of the Alps.

PubMed

Bebi, P; Seidl, R; Motta, R; Fuhr, M; Firm, D; Krumm, F; Conedera, M; Ginzler, C; Wohlgemuth, T; Kulakowski, D

2017-03-15

Natural disturbances, such as avalanches, snow breakage, insect outbreaks, windthrow or fires shape mountain forests globally. However, in many regions over the past centuries human activities have strongly influenced forest dynamics, especially following natural disturbances, thus limiting our understanding of natural ecological processes, particularly in densely-settled regions. In this contribution we briefly review the current understanding of changes in forest cover, forest structure, and disturbance regimes in the mountain forests across the European Alps over the past millennia. We also quantify changes in forest cover across the entire Alps based on inventory data over the past century. Finally, using the Swiss Alps as an example, we analyze in-depth changes in forest cover and forest structure and their effect on patterns of fire and wind disturbances, based on digital historic maps from 1880, modern forest cover maps, inventory data on current forest structure, topographical data, and spatially explicit data on disturbances. This multifaceted approach presents a long-term and detailed picture of the dynamics of mountain forest ecosystems in the Alps. During pre-industrial times, natural disturbances were reduced by fire suppression and land-use, which included extraction of large amounts of biomass that decreased total forest cover. More recently, forest cover has increased again across the entire Alps (on average +4% per decade over the past 25-115 years). Live tree volume (+10% per decade) and dead tree volume (mean +59% per decade) have increased over the last 15-40 years in all regions for which data were available. In the Swiss Alps secondary forests that established after 1880 constitute approximately 43% of the forest cover. Compared to forests established previously, post-1880 forests are situated primarily on steep slopes (>30°), have lower biomass, a more aggregated forest structure (primarily stem-exclusion stage), and have been more strongly

Pre-Alpine contrasting tectono-metamorphic evolutions within the Southern Steep Belt, Central Alps

NASA Astrophysics Data System (ADS)

Roda, Manuel; Zucali, Michele; Li, Zheng-Xiang; Spalla, Maria Iole; Yao, Weihua

2018-06-01

In the Southern Steep Belt, Italian Central Alps, relicts of the pre-Alpine continental crust are preserved. Between Valtellina and Val Camonica, a poly-metamorphic rock association occurs, which belongs to the Austroalpine units and includes two classically subdivided units: the Languard-Campo nappe (LCN) and the Tonale Series (TS). The outcropping rocks are low to medium grade muscovite, biotite and minor staurolite-bearing gneisses and micaschists, which include interlayered garnet- and biotite-bearing amphibolites, marbles, quartzites and pegmatites, as well as sillimanite-bearing gneisses and micaschists. Permian intrusives (granitoids, diorites and minor gabbros) emplaced in the metamorphic rocks. We performed a detailed structural, petrological and geochronological analysis focusing on the two main lithotypes, namely, staurolite-bearing micaschists and sillimanite-bearing paragneisses, to reconstruct the Variscan and Permian-Triassic history of this crustal section. The reconstruction of the tectono-metamorphic evolution allows for the distinction between two different tectono-metamorphic units during the early pre-Alpine evolution (D1) and predates the Permian intrusives, which comprise rocks from both TS and LCN. In the staurolite-bearing micaschists, D1 developed under amphibolite facies conditions (P = 0.7-1.1 GPa, T = 580-660 °C), while in the sillimanite-bearing paragneisses formed under granulite facies conditions (P = 0.6-1.0 GPa, T> 780 °C). The two tectono-metamorphic units coupled together during the second pre-Alpine stage (D2) under granulite-amphibolite facies conditions at a lower pressure (P = 0.4-0.6 GPa, T = 620-750 °C) forming a single tectono-metamorphic unit (Languard-Tonale Tectono-Metamorphic Unit), which comprised the previously distinguished LCN and TS. Geochronological analyses on zircon rims indicate ages ranging between 250 and 275 Ma for D2, contemporaneous with the emplacement of Permian intrusives. This event developed under

Characterization and Manipulation of the Pathway-Specific Late Regulator AlpW Reveals Streptomyces ambofaciens as a New Producer of Kinamycins ▿ †

PubMed Central

Bunet, Robert; Song, Lijiang; Mendes, Marta Vaz; Corre, Christophe; Hotel, Laurence; Rouhier, Nicolas; Framboisier, Xavier; Leblond, Pierre; Challis, Gregory L.; Aigle, Bertrand

2011-01-01

The genome sequence of Streptomyces ambofaciens, a species known to produce the congocidine and spiramycin antibiotics, has revealed the presence of numerous gene clusters predicted to be involved in the biosynthesis of secondary metabolites. Among them, the type II polyketide synthase-encoding alp cluster was shown to be responsible for the biosynthesis of a compound with antibacterial activity. Here, by means of a deregulation approach, we gained access to workable amounts of the antibiotics for structure elucidation. These compounds, previously designated as alpomycin, were shown to be known members of kinamycin family of antibiotics. Indeed, a mutant lacking AlpW, a member of the TetR regulator family, was shown to constitutively produce kinamycins. Comparative transcriptional analyses showed that expression of alpV, the essential regulator gene required for activation of the biosynthetic genes, is strongly maintained during the stationary growth phase in the alpW mutant, a stage at which alpV transcripts and thereby transcripts of the biosynthetic genes normally drop off. Recombinant AlpW displayed DNA binding activity toward specific motifs in the promoter region of its own gene and that of alpV and alpZ. These recognition sequences are also targets for AlpZ, the γ-butyrolactone-like receptor involved in the regulation of the alp cluster. However, unlike that of AlpZ, the AlpW DNA-binding ability seemed to be insensitive to the signaling molecules controlling antibiotic biosynthesis. Together, the results presented in this study reveal S. ambofaciens to be a new producer of kinamycins and AlpW to be a key late repressor of the cellular control of kinamycin biosynthesis. PMID:21193612

Preserved organic matter in the Serpentinized Ocean-Continent Transition of Alpine Tethys

NASA Astrophysics Data System (ADS)

Mateeva, T.; Wolff, G. A.; Kusznir, N.; Manatschal, G.; Wheeler, J.

2017-12-01

Serpentinization occurs at slow-spreading ocean ridges and magma-poor rifted continental margins. At modern hydrothermal vents, serpentinization has been observed to support hydrogen-driven microbial environments including methanotrophic biosystems. An important question is: "Are such bio-systems locally restricted to hydrothermal vents or are they more pervasive, being linked with the exhumation of serpentinized mantle at the seafloor?" Fieldwork sampling of km scale exposures of orogenically exhumed serpentinized mantle in the Alps allows 3D mantle sampling that is not possible at ocean ridges and provides an opportunity to investigate the organic matter in an ophiolite sequence relative to the seafloor. Samples from the fossil Tethyan OCT, exhumed during Alpine collisional orogeny, have been examined for the presence or absence of biomarkers typical of methanotrophy within serpentinized exhumed mantle. Samples from the Totalp unit, Tasna nappe and Platta unit of the Eastern Swiss Alps and Chenaillet in the Western Alps from the Tethyan magma-poor OCT were selected for analysis because they have little Alpine deformation and underwent only low-grade Alpine metamorphism. Hand specimens and cores taken from these locations have been analysed to search for the presence or absence of biomarkers in the serpentinite and its overlying lithologies. Thin sections of samples from these OCT locations reveal multiple serpentinization events and calcification phases. All the lithologies sampled show the presence of hydrocarbons such as n-alkanes, low molecular weight polynuclear aromatic hydrocarbons (PAHs, of mixed petrogenic and pyrogenic source), hopanes, steranes (of marine origin), and branched alkanes (pristane and phytane, non-specific marine origin). The identifiable biomarkers and the isotopic data are consistent with organic matter of a marine origin and do not provide any evidence for a methanotrophic bio-system. It is noteworthy that basement mantle rocks still

Pleistocene alterations of drainage network between the Alps and the Pannonian Basin

NASA Astrophysics Data System (ADS)

Kovács, G.

2012-04-01

markers (wide alluvial valleys with relatively small streams, terrace levels and wind gaps) and the different height of the scarps we roughly elaborated the geomorphological development of the area, including relative age of drainage network elements, tectonic features and river captures. Results indicate a detailed but still regionally dissected timeline about drainage network alterations, including phases of gravel sedimentation, incision and beheadings. The abstract titled "Pleistocene alteration of drainage network and surface morphology caused by basement structure in the foreland of Eastern Alps" determine the origin of the investigated scarps. This paper was supported by Hungarian Scientific Research Fund (OTKA NK83400). Joó, I. (1992): Recent vertical surface movements in the Carpathian Basin. Tectonophysics 202: 129-134. Kovács, G., Telbisz, T., Székely, B. (2010) Faulted and eroded gravel deposit in western Hungary. - Geophysical Research Abstracts Vol. 12. EGU General Assembly 2010. Kovács, G., Telbisz, T., Székely, B. (2011) Quaternary alterations of drainage network in a transition area between the Alps and the Pannonian Basin. - Geophysical Research Abstracts Vol. 13. EGU General Assembly 2011. Tari, G. and Horváth, F. (1995): Middle Miocene extensional collapse in the Alpine-Pannonian transitional zone, in: Horváth, F., Tari, G., and Bokor, K. (Eds.): Extensional collapse of the Alpine orogene and hydrocarbon prospects in the basement and fill of the western Pannonian Basin, AAPG Inter. Conf. and Exhib., Nice, France, Guidebook to fieldtrip No. 6, 75-105

Revealing heterogeneous nucleation of primary Si and eutectic Si by AlP in hypereutectic Al-Si alloys.

PubMed

Li, Jiehua; Hage, Fredrik S; Liu, Xiangfa; Ramasse, Quentin; Schumacher, Peter

2016-04-28

The heterogeneous nucleation of primary Si and eutectic Si can be attributed to the presence of AlP. Although P, in the form of AlP particles, is usually observed in the centre of primary Si, there is still a lack of detailed investigations on the distribution of P within primary Si and eutectic Si in hypereutectic Al-Si alloys at the atomic scale. Here, we report an atomic-scale experimental investigation on the distribution of P in hypereutectic Al-Si alloys. P, in the form of AlP particles, was observed in the centre of primary Si. However, no significant amount of P was detected within primary Si, eutectic Si and the Al matrix. Instead, P was observed at the interface between the Al matrix and eutectic Si, strongly indicating that P, in the form of AlP particles (or AlP 'patch' dependent on the P concentration), may have nucleated on the surface of the Al matrix and thereby enhanced the heterogeneous nucleation of eutectic Si. The present investigation reveals some novel insights into heterogeneous nucleation of primary Si and eutectic Si by AlP in hypereutectic Al-Si alloys and can be used to further develop heterogeneous nucleation mechanisms based on adsorption.

Fast and sensitive near-infrared fluorescent probes for ALP detection and 3d printed calcium phosphate scaffold imaging in vivo.

PubMed

Park, Chul Soon; Ha, Tai Hwan; Kim, Moonil; Raja, Naren; Yun, Hui-Suk; Sung, Mi Jeong; Kwon, Oh Seok; Yoon, Hyeonseok; Lee, Chang-Soo

2018-05-15

Alkaline phosphatase (ALP) is a critical biological marker for osteoblast activity during early osteoblast differentiation, but few biologically compatible methods are available for its detection. Here, we describe the discovery of highly sensitive and rapidly responsive novel near-infrared (NIR) fluorescent probes (NIR-Phos-1, NIR-Phos-2) for the fluorescent detection of ALP. ALP cleaves the phosphate group from the NIR skeleton and substantially alters its photophysical properties, therefore generating a large "turn-on" fluorescent signal resulted from the catalytic hydrolysis on fluorogenic moiety. Our assay quantified ALP activity from 0 to 1.0UmL -1 with a 10 -5 -10 -3 UmL -1 limit of detection (LOD), showing a response rate completed within 1.5min. A potentially powerful approach to probe ALP activity in biological systems demonstrated real-time monitoring using both concentration- and time-dependent variations of endogenous ALP in live cells and animals. Based on high binding affinity to bone tissue of phosphate moiety, bone-like scaffold-based ALP detection in vivo was accessed using NIR probe-labeled three-dimensional (3D) calcium deficient hydroxyapatite (CDHA) scaffolds. They were subcutaneously implanted into mice and monitored ALP signal changes using a confocal imaging system. Our results suggest the possibility of early-stage ALP detection during neo-bone formation inside a bone defect, by in vivo fluorescent evaluation using 3D CDHA scaffolds. Copyright © 2018 Elsevier B.V. All rights reserved.

Palinspastic reconstruction of the Alpine thrust belt at the Alpine-Carpathian transition - A geological Sudoku

NASA Astrophysics Data System (ADS)

Beidinger, A.; Decker, K.; Zamolyi, A.; Hölzel, M.; Hoprich, M.; Strauss, P.

2009-04-01

The palinspastic reconstruction of the Austroalpine thrust belt is part of the project Karpatian Tectonics, which is funded by OMV Austria. The objective is to reconstruct the evolution of the thrust belt through the Early to Middle Miocene in order to obtain information on the palaeogeographic position of the Northern Calcareous Alps (NCA) in the region of the present Vienna Basin. A particular goal of the study is to constrain the position of reservoir rocks within the Rhenodanubic Flysch units and the NCA with respect to the autochthonous Malmian source rocks overlying the European basement below the Alpine-Carpathian thrust wedge, and to constrain the burial history of these source rocks. Reconstruction uses regional 2D seismic lines crossing from the European foreland into the fold-thrust belt, 3D seismic data covering the external thrust sheets, and lithostratigraphic data from a total of 51 selected wells, which were drilled and provided by OMV Austria. The main criterion, whether a well was suitable for palinspastic reconstruction or not, was its penetration of Alpine thrust sheets down to the Autochthonous Molasse of the foreland. Additional wells, which do not penetrate the entire Alpine thrust complex but include the Allochthonous Molasse or the external Alpine-Carpathian nappes (Waschberg and Roseldorf thrust unit, Rhenodanubic Flysch nappes) in their well path, were also taken into account. The well data in particular comprise stratigraphic information on the youngest overthrust sediments of the different thrust units and the underlying Autochthonous foreland Molasse. These data allow constraining the timing of thrust events in the allochthonous thrust units and overthrusting of the Autochthonous Molasse. In the particular case of overthrust Autochthonous Molasse, additionally to the timing of overthrusting, which can be derived from the youngest overthrust sediments, the palaeogeographic position of the Alpine Carpathian thrust front could directly be

The onset of alpine pastoral systems in the Eastern Alps

NASA Astrophysics Data System (ADS)

Oeggl, Klaus; Festi, Daniela; Putzer, Andreas

2015-04-01

Since the discovery of the Neolithic glacier mummy "Ötzi" in the nival belt of the main Alpine ridge, the onset of alpine pasture is matter of a highly controversial debate both in archaeology and in palaeo-ecology of the Eastern Alps. The implication is that his sojourn in the high-altitudes of the Alps is considered to be connected with pastoral nomadism. Regrettably any archaeological evidence for the existence of such Neolithic alpine pastoral systems is missing up to now and the assumption is based on palynological data only. However, also the palynological record is ambiguous, because pasture indicators in the alpine regions react positive on grazing as well as on fertilization induced by a higher runoff of precipitation. Thus alpine pasture indicators reflect both grazing pressure and climatic change. Anyhow, alpine pastoral systems are a common practice in Alpine animal husbandry, but from an economic point of view such a seasonal vertical transhumance is costly. There are three main reasons for its practice: i) climatic, ii) economic (mainly in connection with population pressure or mining activities), and iii) cultural ideology. In this study we tested the above mentioned reasons in an interdisciplinary study on the beginning of pastoral activities in high altitudes in the central part of the Eastern Alps. This is conducted by palynological analyses of peat deposits situated in the vicinity of the timberline (1600 - 2400 m a.s.l.) combined with archaeological surveys. The investigated sites are located in traditional Alpine transhumance regions and aligned on a transect through the central part of the Eastern Alps. The studies reveal that grazing pressure is reflected since the Bronze Age, which is corroborated by archaeological findings in the vicinity of the investigated sites.

Last Glacial Maximum Dated by Means of 10Be in the Maritime Alps (Italy)

NASA Astrophysics Data System (ADS)

Granger, D. E.; Spagnolo, M.; Federici, P.; Pappalardo, M.; Ribolini, A.; Cyr, A. J.

2006-12-01

Relatively few exposure dates of LGM moraines boulders are available for the European Alps, and none on the southern flank. Ponte Murato (PM) is a frontal moraine at 860 m asl in the Gesso Basin (Maritime Alps, SW European Alps). The PM moraine dams the 157 km2 Gesso della Barra Valley and it represents the lowermost frontal moraine of the entire Gesso Valley, near the outlet of the valley in the Po Plain. Its ELA, determined from the paleo- shape of the supposed Gesso della Barra glacier, is 1746 m asl. Tetti Bandito (TB) is a small and badly preserved glacial deposit, tentatively attributed to a lateral-frontal moraine, that is positioned 5 km downvalley from the PM deposit at 800 m asl. There are no other glacial deposits downvalley from the TB moraine in the Gesso Basin or farther NE in the piedmont region of the upper Po Plain. Boulders sampled on the PM and on the TB moraine crests gave a 10Be cosmogenic age of respectively 16300 ± 880 ka (average value) and 18798 ± 973 ka. This result constrains the PM frontal moraine within the LGM interval but also suggests that the maximum expansion of the Gesso Basin glacier was more downvalley at some point during the last glaciation. If the TB is a lateral-frontal moraine as supposed, the two TB and PM moraines would represent the outer and inner moraine crests of the same LGM stadial, with the outer moraine much less pronounced than the inner moraine, similarly to the maximalstand and the hochstand described in the Eastern Alps (Van Husen, 1997). Within this perspective, the PM and TB dates are consistent with a European Alps LGM corresponding to MIS 2 (Ivy-Ochs et al., 2004). This study of the Maritime Alps moraines is also in agreement with the Upper Würm climatic theory (Florineth and Schlüchter, 2000) of a stronger influence of the W and SW incoming humid airflows in the European Alps, differently from the nearby Vosges and Pyrenees mountain chains where more dry conditions were probably responsible for a very

Coupled effects of wind-storms and drought on tree mortality across 115 forest stands from the Western Alps and the Jura mountains.

PubMed

Csilléry, Katalin; Kunstler, Georges; Courbaud, Benoît; Allard, Denis; Lassègues, Pierre; Haslinger, Klaus; Gardiner, Barry

2017-12-01

Damage due to wind-storms and droughts is increasing in many temperate forests, yet little is known about the long-term roles of these key climatic factors in forest dynamics and in the carbon budget. The objective of this study was to estimate individual and coupled effects of droughts and wind-storms on adult tree mortality across a 31-year period in 115 managed, mixed coniferous forest stands from the Western Alps and the Jura mountains. For each stand, yearly mortality was inferred from management records, yearly drought from interpolated fields of monthly temperature, precipitation and soil water holding capacity, and wind-storms from interpolated fields of daily maximum wind speed. We performed a thorough model selection based on a leave-one-out cross-validation of the time series. We compared different critical wind speeds (CWSs) for damage, wind-storm, and stand variables and statistical models. We found that a model including stand characteristics, drought, and storm strength using a CWS of 25 ms -1 performed the best across most stands. Using this best model, we found that drought increased damage risk only in the most southerly forests, and its effect is generally maintained for up to 2 years. Storm strength increased damage risk in all forests in a relatively uniform way. In some stands, we found positive interaction between drought and storm strength most likely because drought weakens trees, and they became more prone to stem breakage under wind-loading. In other stands, we found negative interaction between drought and storm strength, where excessive rain likely leads to soil water saturation making trees more susceptible to overturning in a wind-storm. Our results stress that temporal data are essential to make valid inferences about ecological impacts of disturbance events, and that making inferences about disturbance agents separately can be of limited validity. Under projected future climatic conditions, the direction and strength of these

Structure and U-Pb zircon geochronology of an Alpine nappe stack telescoped by extensional detachment faulting (Kulidzhik area, Eastern Rhodopes, Bulgaria)

NASA Astrophysics Data System (ADS)

Georgiev, Neven; Froitzheim, Nikolaus; Cherneva, Zlatka; Frei, Dirk; Grozdev, Valentin; Jahn-Awe, Silke; Nagel, Thorsten J.

2016-10-01

The Rhodope Metamorphic Complex is a stack of allochthons assembled during obduction, subduction, and collision processes from Jurassic to Paleogene and overprinted by extensional detachment faults since Middle Eocene. In the study area, the following nappes occur in superposition (from base to top): an orthogneiss-dominated unit (Unit I), garnet-bearing schist with amphibolite and serpentinite lenses (Unit II), greenschist, phyllite, and calcschist with reported Jurassic microfossils (Unit III), and muscovite-rich orthogneiss (Unit IV). U-Pb dating of zircons from a K-feldspar augengneiss (Unit I) yielded a protolith age of ca. 300 Ma. Garnet-bearing metasediment from Unit II yielded an age spectrum with distinct populations between 310 and 250 Ma (detrital), ca. 150 Ma, and ca. 69 Ma (the last two of high-grade metamorphic origin). An orthogneiss from Unit IV yielded a wide spectrum of ages. The youngest population gives a concordia age of 581 ± 5 Ma, interpreted as the age of the granitic protolith. Unit I represents the Lower Allochthon (Byala Reka-Kechros Dome), Unit II the Upper Allochthon (Krumovitsa-Kimi Unit), Unit III the Uppermost Allochthon (Circum-Rhodope Belt), and Unit IV a still higher, far-travelled unit of unknown provenance. Telescoping of the entire Rhodope nappe stack to a thickness of only a few 100 m is due to Late Eocene north directed extensional shearing along the newly defined Kulidzhik Detachment which is part of a major detachment system along the northern border of the Rhodopes. Older top-to-the south mylonites in Unit I indicate that Tertiary extension evolved from asymmetric (top-to-the-south) to symmetric (top-to-the-south and top-to-the-north), bivergent unroofing.

ALP conversion and the soft X-ray excess in the outskirts of the Coma cluster

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kraljic, David; Rummel, Markus; Conlon, Joseph P., E-mail: David.Kraljic@physics.ox.ac.uk, E-mail: Markus.Rummel@physics.ox.ac.uk, E-mail: j.conlon1@physics.ox.ac.uk

2015-01-01

It was recently found that the soft X-ray excess in the center of the Coma cluster can be fitted by conversion of axion-like-particles (ALPs) of a cosmic axion background (CAB) to photons. We extend this analysis to the outskirts of Coma, including regions up to 5 Mpc from the center of the cluster. We extract the excess soft X-ray flux from ROSAT All-Sky Survey data and compare it to the expected flux from ALP to photon conversion of a CAB. The soft X-ray excess both in the center and the outskirts of Coma can be simultaneously fitted by ALP tomore » photon conversion of a CAB. Given the uncertainties of the cluster magnetic field in the outskirts we constrain the parameter space of the CAB. In particular, an upper limit on the CAB mean energy and a range of allowed ALP-photon couplings are derived.« less

Reaching and abandoning the furthest ice extent during the Last Glacial Maximum in the Alps

NASA Astrophysics Data System (ADS)

Ivy-Ochs, Susan; Wirsig, Christian; Zasadni, Jerzy; Hippe, Kristina; Christl, Marcus; Akçar, Naki; Schluechter, Christian

2016-04-01

During the Last Glacial Maximum (LGM) in the European Alps (late Würm) local ice caps and extensive ice fields in the high Alps fed huge outlet glaciers that occupied the main valleys and extended onto the forelands as piedmont lobes. Records from numerous sites suggest advance of glaciers beyond the mountain front by around 30 ka (Ivy-Ochs 2015 and references therein). Reaching of the maximum extent occurred by about 27-26 ka, as exemplified by dates from the Rhein glacier area (Keller and Krayss, 2005). Abandonment of the outermost moraines at sites north and south of the Alps was underway by about 24 ka. In the high Alps, systems of transection glaciers with transfluences over many of the Alpine passes dominated, for example, at Grimsel Pass in the Central Alps (Switzerland). 10Be exposure ages of 23 ± 1 ka for glacially sculpted bedrock located just a few meters below the LGM trimline in the Haslital near Grimsel Pass suggest a pulse of ice surface lowering at about the same time that the foreland moraines were being abandoned (Wirsig et al., 2016). Widespread ice surface lowering in the high Alps was underway by no later than 18 ka. Thereafter, glaciers oscillated at stillstand and minor re-advance positions on the northern forelands for several thousand years forming the LGM stadial moraines. Final recession back within the mountain front took place by 19-18 ka. Recalculation to a common basis of all published 10Be exposure dates for boulders situated on LGM moraines suggests a strong degree of synchrony for the timing of onset of ice decay both north and south of the Alps. Ivy-Ochs, S., 2015, Cuadernos de investigación geográfica 41: 295-315. Keller, O., Krayss, E., 2005, Vierteljahrschr. Naturforsch. Gesell. Zürich 150: 69-85. Wirsig, C. et al., 2016, J. Quat. Sci. 31: 46-59.

13 CFR 120.841 - Qualifications for the ALP.

Code of Federal Regulations, 2014 CFR

2014-01-01

.... An applicant for ALP status must show that it substantially meets the following criteria: (a) CDC staff experience. The CDC's staff must have well-trained, qualified loan officers who are knowledgeable concerning SBA's lending policies and procedures for the 504 program. The CDC must have at least one loan...

13 CFR 120.841 - Qualifications for the ALP.

Code of Federal Regulations, 2012 CFR

2012-01-01

.... An applicant for ALP status must show that it substantially meets the following criteria: (a) CDC staff experience. The CDC's staff must have well-trained, qualified loan officers who are knowledgeable concerning SBA's lending policies and procedures for the 504 program. The CDC must have at least one loan...

13 CFR 120.841 - Qualifications for the ALP.

Code of Federal Regulations, 2013 CFR

2013-01-01

.... An applicant for ALP status must show that it substantially meets the following criteria: (a) CDC staff experience. The CDC's staff must have well-trained, qualified loan officers who are knowledgeable concerning SBA's lending policies and procedures for the 504 program. The CDC must have at least one loan...

13 CFR 120.841 - Qualifications for the ALP.

Code of Federal Regulations, 2011 CFR

2011-01-01

.... An applicant for ALP status must show that it substantially meets the following criteria: (a) CDC staff experience. The CDC's staff must have well-trained, qualified loan officers who are knowledgeable concerning SBA's lending policies and procedures for the 504 program. The CDC must have at least one loan...

Cutting-edge Kinetic Physics with Parker Solar Probe and Solar Orbiter: The Arbitrary Linear Plasma Solver (ALPS)

NASA Astrophysics Data System (ADS)

Verscharen, D.; Klein, K. G.; Chandran, B. D. G.; Stevens, M. L.; Salem, C. S.; Bale, S. D.

2017-12-01

The Arbitrary Linear Plasma Solver (ALPS) is a parallelized numerical code that solves the dispersion relation in a hot (even relativistic) magnetized plasma with an arbitrary number of particle species with arbitrary gyrotropic equilibrium distribution functions for any direction of wave propagation with respect to the background field. In this way, ALPS retains generality and overcomes the shortcomings of previous (bi-)Maxwellian solvers for the plasma dispersion relations. The unprecedented high-resolution particle and field data products from Parker Solar Probe (PSP) and Solar Orbiter (SO) will require novel theoretical tools. ALPS is one such tool, and its use will make possible new investigations into the role of non-Maxwellian distributions in the near-Sun solar wind. It can be applied to numerous high-velocity-resolution systems, ranging from current space missions to numerical simulations. We will briefly discuss the ALPS algorithm and demonstrate its functionality based on previous solar-wind measurements. We will then highlight our plans for future applications of ALPS to PSP and SO observations.

The tectono-thermal evolution of the Waterbury dome, western Connecticut, based on U-Pb and 40Ar/39Ar ages

USGS Publications Warehouse

Dietsch, Craig; Kunk, Michael J.; Aleinikoff, John; Sutter, John F.

2010-01-01

Level 3 nappes were emplaced over the Waterbury dome along an Acadian décollement synchronous with the formation of a D3 thrust duplex in the dome. The décollement truncates the Ky + Kfs-in (migmatite) isograd in the dome core and a St-in isograd in level 3 nappes, indicating that peak metamorphic conditions in the dome core and nappe cover rocks formed in different places at different times. Metamorphic overgrowths on zircon from the felsic orthogneiss in the Waterbury dome have an age of 387 ± 5 Ma. Rocks of all levels and the décollement are folded by D4 folds that have a strongly developed, regional crenulation cleavage and D5 folds. The Waterbury dome was formed by thrust duplexing followed by fold interference during the Acadian orogeny. The 40Ar/39Ar ages of amphibole, muscovite, biotite, and K-feldspar from above and below the décollement are ca. 378 Ma, 355 Ma, 360 Ma (above) and 340 (below), and 288 Ma, respectively. Any kilometer-scale vertical movements between dome and nappe rocks were over by ca. 378 Ma. Core and cover rocks of the Waterbury dome record synchronous, post-Acadian cooling.

Use of Rituximab for Refractory Cytopenias Associated with Autoimmune Lymphoproliferative Syndrome (ALPS)

PubMed Central

Rao, V. Koneti; Price, Susan; Perkins, Katie; Aldridge, Patricia; Tretler, Jean; Davis, Joie; Dale, Janet K.; Gill, Fred; Hartman, Kip R.; Stork, Linda C.; Gnarra, David J.; Krishnamurti, Lakshmanan; Newburger, Peter E.; Puck, Jennifer; Fleisher, Thomas

2009-01-01

Background ALPS is a disorder of apoptosis resulting in accumulation of autoreactive lymphocytes, leading to marked lymphadenopathy, hepatosplenomegaly and multilineage cytopenias due to splenic sequestration and/or autoimmune destruction often presenting in childhood. We summarize our experience of rituximab use during the last 8 years in twelve patients, 9 children and 3 adults, out of 259 individuals with ALPS, belonging to 166 families currently enrolled in studies at the National Institutes of Health. Methods Refractory immune thrombocytopenia (platelet count <20,000) in 9 patients and autoimmune hemolytic anemia (AIHA) in 3 patients led to treatment with rituximab. Among them, 7 patients had undergone prior surgical splenectomy; 3 had significant splenomegaly; and 2 had no palpable spleen. Results In 7 out of 9 patients with ALPS and thrombocytopenia, rituximab therapy led to median response duration of 21months (range 14–36 months). In contrast, none of the 3 children treated with rituximab for AIHA responded. Noted toxicities included profound and prolonged hypogammaglobulinemia in 3 patients requiring replacement IVIG, total absence of antibody response to polysaccharide vaccines lasting up to 4 years after rituximab infusions in 1 patient and prolonged neutropenia in 1 patient. Conclusion Toxicities including hypogammaglobulinemia and neutropenia constitute an additional infection risk burden, especially in asplenic individuals, and may warrant avoidance of rituximab until other immunosuppressive medication options are exhausted. Long term follow up of ALPS patients with cytopenias after any treatment is necessary to determine relative risks and benefits. PMID:19214977

Effects of atmospheric and climate change at the timberline of the Central European Alps

PubMed Central

Wieser, Gerhard; Matyssek, Rainer; Luzian, Roland; Zwerger, Peter; Pindur, Peter; Oberhuber, Walter; Gruber, Andreas

2011-01-01

This review considers potential effects of atmospheric change and climate warming within the timberline ecotone of the Central European Alps. After focusing on the impacts of ozone (O3) and rising atmospheric CO2 concentration, effects of climate warming on the carbon and water balance of timberline trees and forests will be outlined towards conclusions about changes in tree growth and treeline dynamics. Presently, ambient ground-level O3 concentrations do not exert crucial stress on adult conifers at the timberline of the Central European Alps. In response to elevated atmospheric CO2 Larix decidua showed growth increase, whereas no such response was found in Pinus uncinata. Overall climate warming appears as the factor responsible for the observed growth stimulation of timberline trees. Increased seedling re-establishment in the Central European Alps however, resulted from invasion into potential habitats rather than upward migration due to climate change, although seedlings will only reach tree size upon successful coupling with the atmosphere and thus loosing the beneficial microclimate of low stature vegetation. In conclusion, future climate extremes are more likely than the gradual temperature increase to control treeline dynamics in the Central European Alps. PMID:21379395

Holocene geological records of flood regime in French Alps

NASA Astrophysics Data System (ADS)

Arnaud, Fabien; Wilhelm, Bruno; Giguet-Covex, Charline; Jenny, Jean-Philippe; Fouinat, Laurent; Sabatier, Pierre; Debret, Maxime; Révillon, Sidonie; Chapron, Emmanuel; Revel, Marie

2014-05-01

In this paper we present a review of a ca. 10-years research effort (1-9) aiming at reconstructing floods dynamics in in French Alps through the Holocene, based on lake sediment records. We will particularly discuss how such geological records can be considered as representative of past climate. This implies a wise interpretation of data in order to really understand "what does the core really says". Namely, we showed that different lake systems record different types of flood events. Low altitude lakes, fed by large-scale catchment areas are more sensitive to regional heavy rainfall events (2-5), whereas high altitude small lakes record local extreme rainfall events (6). Moreover, human societies' development must be taken into account as it is susceptible to modulate the climate-geological record relationship (7). Altogether our data permit the establishment of a Holocene-long perspective upon both regional heavy rainfall and torrential activities in high elevation sites. We hence show that both types of events frequency co-evolve in Northern as well as Southern French Alps where Holocene colder spells generally present higher flood frequencies (6-9). On the other hand, intensities of torrential events present a North-South opposite pattern: during warm spells (e.g. the Medieval Warm Period or nowadays), northern Alps are subject to rare but extremely intense heavy rainfall events, whereas in the southern Alps torrential floods are both rare and weak. During cold spells (e.g. the Little Ice Age), the inverse pattern is observed: torrential floods are more frequent everywhere and above-average intensity in Southern Alps. This point is particularly important for risk management in mountain areas in a context of global warming. Our results point out how complex can be the response of regional system to global climate changes. We are hence far from completely understanding this complexity which is moreover imperfectly simulated by climate models. As geological

Brittle deformation and exhumation mechanisms in the core of the Eastern Alps, The Tauern Window

NASA Astrophysics Data System (ADS)

Bertrand, Audrey; Garcia, Sebastian; Rosenberg, Claudio

2010-05-01

. Taken together, our results suggest that the brittle crust of the TW was mostly affected by a strike-slip state of stress, which grades into extension at the eastern and western margins of the dome. This suggests that the inverse regime associated with the upright folds terminated before these structures entered the brittle field. Hence, the strike-slip regime postdates in a short time-span the reverse one. The brittle crust of the TW affected by the pure-compressional regime may have been eroded or perhaps there was never any compression after the crust was exhumed to above the ductile-brittle transition. References Grundmann, G., and Morteani, G., 1985, The young uplift and thermal history of the central Eastern Alps (Austria/Italy), evidence from apatite fission track ages. Jahrb. der Geo. Bundesanstalt, 128, 197-216. Ratschbacher, L., Frisch, W., Neubauer, F., Schmid, S. M., and Neugebauer, J., 1989, Extension in compressional orogenic belts: The eastern Alps. Geology, 17, 404-407. Rosenberg, C. L., Brun, J.-P., and Gapais, D., 2004, An indentation model of the Eastern Alps and the origin of the Tauern Window. Geology, 32, 997-1000. Schneider, S., Bertrand, A. & Rosenberg, C.L. The Jaufental Fault: a kinematic link between the Tauern Window and south-Alpine Indentation. Abstract EGU2010. Selverstone, J., 1988, Evidence for East-West crustal extension in the eastern Alps: implications for the unroofing history of the Tauern Window. Tectonics, 7, 87-105. Selverstone, J., Franz, G., Thomas, S., Getty, S., 1992. Fluid variability in 2 GPa eclogites as an indicator of fluid behavior during subduction. Contributions to Mineralogy and Petrology 112, 341-357.

Wolf survival and population trend using non-invasive capture-recapture techniques in the Western Alps

Treesearch

Francesca Marucco; Daniel H. Pletscher; Luigi Boitani; Michael K. Schwartz; Kristy L. Pilgrim; Jean-Dominique Lebreton

2009-01-01

Population abundance and related parameters need to be assessed to implement effective wildlife management. These essential parameters are often very hard to obtain for rare, wide-ranging and elusive species, particularly those listed as endangered or threatened (IUCN 2001). In Italy, wolves Canis lupus Linnaeus 1758, now a fully protected species in Western Europe,...

Organic petrology of Paleocene Marcelina Formation coals, Paso Diablo mine, western Venezuela: Tectonic controls on coal type

USGS Publications Warehouse

Hackley, P.C.; Martinez, M.

2007-01-01

About 7??Mt of high volatile bituminous coal are produced annually from the four coal zones of the Upper Paleocene Marcelina Formation at the Paso Diablo open-pit mine of western Venezuela. As part of an ongoing coal quality study, we have characterized twenty-two coal channel samples from the mine using organic petrology techniques. Samples also were analyzed for proximate-ultimate parameters, forms of sulfur, free swelling index, ash fusion temperatures, and calorific value. Six of the samples represent incremental benches across the 12-13??m thick No. 4 bed, the stratigraphically lowest mined coal, which is also mined at the 10??km distant Mina Norte open-pit. Organic content of the No. 4 bed indicates an upward increase of woody vegetation and/or greater preservation of organic material throughout the life of the original mire(s). An upward increase in telovitrinite and corresponding decrease in detrovitrinite and inertinite illustrate this trend. In contrast, stratigraphically higher coal groups generally exhibit a 'dulling upward' trend. The generally high inertinite content, and low ash yield and sulfur content, suggest that the Paso Diablo coals were deposited in rain-fed raised mires, protected from clastic input and subjected to frequent oxidation and/or moisture stress. However, the two thinnest coal beds (both 0.7??m thick) are each characterized by lower inertinite and higher telovitrinite content relative to the rest of Paso Diablo coal beds, indicative of less well-established raised mire environments prior to drowning. Foreland basin Paleocene coals of western Venezuela, including the Paso Diablo deposit and time-correlative coal deposits of the Ta??chira and Me??rida Andes, are characterized by high inertinite and consistently lower ash and sulfur relative to Eocene and younger coals of the area. We interpret these age-delimited coal quality characteristics to be due to water availability as a function of the tectonic control of subsidence rate. It

From Tethyan Oceans to the Western Mediterranean I - Plate reconstructions from the Present back to the Early Mesozoic

NASA Astrophysics Data System (ADS)

Schmid, Stefan; Handy, Mark; Bousquet, Romain; Kissling, Eduard; Bernoulli, Daniel

2010-05-01

A new reconstruction of the branches of Alpine Tethys combines available plate kinematic models of Africa-Europe motion with a wealth of new geological and geophysical data (seismic tomography and paleomagnetics) to shed light the evolution of the Western Mediterranean-Alps system, from sea-floor spreading through subduction to collision. Unlike previous models which relate the fate of Alpine Tethys solely to relative motions of the African plate with respect to Europe during opening of the Atlantic, our reconstruction invokes motions and rotations of four additional and temporarily independent microplates: Adria, Iberia, Alcapia and Alkapecia. Translations and rotations of these microplates with respect to Europe are constrained in the following way: (1) The retro-translations of Adria back to 94 Ma are obtained from shortening estimates in the Alps along geological-geophysical transects of the Alpine orogen and from geobarometric estimates of subduction depth in tectonic units that underwent high-pressure and ultrahigh-pressure metamorphism. Rotations are based on paleomagnetic data of Márton et al. (in press); (2) Iberia follows the motion paths of Savostin et al. (1986), based on magnetic anomalies in the Central and Northern Atlantic; the Corsica-Sardinia block later rifted from Iberia leading to Burdigalian opening of the Liguria-Provençal basin (Serranne 1999). (3) The Alcapia microplate, whose name is derived from the acronym ALCAPA (Alps-Carpathians-Pannonian Basin), separated from Adria in Cretaceous times. Its movement with respect to Adria was absorbed by Cretaceous orogeny in the Eastern Alps, constrained by the Adria-Europe displacement and rotation path; later, during Cenozoic orogeny in the Alps, associated with the closing of the Alpine Tethys, it became part of the Adria microplate again. (4) The introduction of an independent Alkapekia continental fragment and independent microplate during the Late Cenozoic only (Alboran

Contrasting environmental memories by ancient soils on different parent rocks in the South-western Italian Alps

NASA Astrophysics Data System (ADS)

D'Amico, Michele; Catoni, Marcella; Bonifacio, Eleonora; Zanini, Ermanno

2014-05-01

Ancient soils (pre-Holocenic paleosols and vetusols) are uncommon on the Alps, because of the extensive Pleistocenic glaciations which erased most of the previously existing soils, the slope steepness and climatic conditions favoring soil erosion. However, in few sites, particularly in the outermost sections of the Alpine range, Pleistocene glaciers covered only small and scattered surfaces because of the low altitude reached in the basins, and ancient soils could be preserved for long periods of time on particularly stable surfaces. We described and sampled soils on 11 stable surfaces in the Upper Tanaro valley, Ligurian Alps (Southwestern Piemonte, Italy). The sampling sites were characterized by low steepness and elevation between 600 to 1600 m, under present day lower montane Castanea sativa/Ostrya carpinifolia forests, montane Fagus sylvatica and Pinus uncinata forests or montane heath/grazed grassland, on different substrata. In particular, we sampled soils developed on dolomite, limestone, quartzite, gneiss and shales. The soils were always well representative of the pedogenic trends active on the respective parent materials, i.e. the skeletal fraction in each soil was always composed of just one rock type, despite the proximity of lithological boundaries and the small dimensions of the different outcrops, often coexisting on the same stable surface. All the considered profiles showed signs of extremely long pedogenesis and/or different phases of intense pedogenesis interrupted by the deposition of periglacial cover beds in the steepest sites. Up to four phases of intense pedogenesis were recognized where cover beds were developed, presumably during cold Pleistocene phases, as present-day climate is not cold enough to create such periglacial morphologies. In such cases, each cover bed underwent similar pedogenesis, strongly dependent on the parent material: on quartzite, podzols with thick E horizons and well developed placic ones were formed in all phases

Possible future lakes resulting from continued glacier shrinkage in the Aosta Valley Region (Western Alps, Italy)

NASA Astrophysics Data System (ADS)

Viani, Cristina; Machguth, Horst; Huggel, Christian; Godio, Alberto; Perotti, Luigi; Giardino, Marco

2017-04-01

Aosta Valley (NW-Alps, Italy) is the region with the largest glaciarized area of Italy (133.73 km2). Like the other alpine regions it has shown a significant glacier retreat starting from the end of the Little Ice Age (LIA, ca. 1850 AD), by losing about 60% of its glaciarized area. As a direct consequence of glacier shrinkage, within glacially-sculpted landscapes, glacier-bed overdeepenings become exposed, offering suitable conditions for glacier lakes formation. In the Aosta Valley region, about 200 glacier lakes have been recognized in different time periods within LIA maximum extent boundaries, mainly dammed by bedrock landforms. With respect to human activities, glacier lakes represent both opportunities (e.g. Miage lake for tourism) and risks (e.g. outburst flood of the Gran Croux lake above Cogne in August 2016) in such a densely populated and developed region. The objective of this contribution is to assess locations of possible future glacier lakes in the Aosta Valley by using the GlabTop2 model (Glacier Bed Topography model version 2). Understanding where future lakes will appear is of fundamental importance for the identification of potential hazards and the interpretation of conditioning factors and dynamics. We first assessed ice thickness and consequently glacier bed topography over large glaciated areas of the region, by using both glaciers outlines related to 1999 (provided by the GlaRiskAlp project) and the regional DEM of 1990 (provided by the Aosta Valley Region) as input data. We performed several runs by varying different input parameters (e,g.: pixel size and basal shear stress). Then we compared modelled results on selected test glaciers (Rutor and Grand Etrèt) with available GPR data. As a validation, we also carried out a GPR survey during summer 2016 on the central area of Indren Glacier (Monte Rosa massif) where GlabTop2 shows the presence of a possible subglacial overdeepening morphology. We found that ice thickness and consequently the

Continuous micro-earthquake catalogue of the central Southern Alps, New Zealand

NASA Astrophysics Data System (ADS)

Michailos, Konstantinos; Townend, John; Savage, Martha; Chamberlain, Calum

2017-04-01

The Alpine Fault is one of the most prominent tectonic features in the South Island, New Zealand, and is inferred to be late in its seismic cycle of M 8 earthquakes based on paleoseismological evidence. Despite this, the Alpine Fault displays low levels of contemporary seismic activity, with little documented on-fault seismicity. This low magnitude seismicity, often below the completeness level of the GeoNet national seismic catalogue, may inform us of changes in fault character along-strike and might be used for rupture simulations and hazard planning. Thus, compiling a micro-earthquake catalogue for the Southern Alps prior to an expected major earthquake is of great interest. Areas of low seismic activity, like the central part of the Alpine Fault, require data recorded over a long duration to reveal temporal and spatial seismicity patterns and provide a better understanding for the processes controlling seismogenesis. The continuity and density of the Southern Alps Microearthquake Borehole Array (SAMBA; deployed in late 2008) allows us to study seismicity in the Southern Alps over a more extended time period than has ever been done previously. Furthermore, by using data from other temporary networks (e.g. WIZARD, ALFA08, DFDP-10) we are able to extend the region covered. To generate a spatially and temporally continuous catalogue of seismicity in New Zealand's central Southern Alps, we used automatic detection and phase-picking methods. We used an automatic phase-picking method for both P- and S- wave arrivals (kPick; Rawles and Thurber, 2015). Using almost 8 years of seismic data we calculated about 9,000 preliminary earthquake. The seismicity is clustered and scattered and a previously observed seismic gap between the Wanganui and Whataroa rivers is also identified.

Bergsteigen in den Alpen (Mountain Climbing in the Alps).

ERIC Educational Resources Information Center

Hawrysz, Ilse; Budzinski, Elisabeth

German second language instructional materials contain a short text in German on mountain climbing in the Alps, a vocabulary list with translation, a simple German climbing song, a recipe for goulash soup in English, and a short text in English on mountain climbing. (MSE)

Seismic anisotropy in localized shear zones versus distributed tectonic fabrics: examples from geologic and seismic observations in western North America and the European Alps

NASA Astrophysics Data System (ADS)

Mahan, Kevin H.; Schulte-Pelkum, Vera; Condit, Cailey; Leydier, Thomas; Goncalves, Philippe; Raju, Anissha; Brownlee, Sarah; Orlandini, Omero F.

2017-04-01

Modern methods for detecting seismic anisotropy offer an array of promising tools for imaging deep crustal deformation but also present challenges, especially with respect to potential biases in both the detection methods themselves as well as in competing processes for localized versus distributed deformation. We address some of these issues from the geophysical perspective by employing azimuthally dependent amplitude and polarity variations in teleseismic receiver functions combined with a compilation of published rock elasticity tensors from middle and deep crustal rocks, and from the geological perspective through studies of shear zone deformation processes. Examples are highlighted at regional and outcrop scales from western North America and the European Alps. First, in regional patterns, strikes of seismically detected fabric from receiver functions in California show a strong alignment with current strike-slip motion between the Pacific and North American plates, with high signal strength near faults and from depths below the brittle-ductile transition suggesting these faults have deep ductile roots. In contrast, despite NE-striking shear zones being the most prominent features portrayed on Proterozoic tectonic maps of the southwestern USA, receiver function anisotropy from the central Rocky Mountain region appears to more prominently reflect broadly distributed Proterozoic fabric domains that preceded late-stage localized shear zones. Possible causes for the discrepancy fall into two categories: those that involve a) bias in seismic sampling and/or b) deformation processes that lead to either weaker anisotropy in the shear zones compared to adjacent domains or to a symmetry that is different from that conventionally assumed. Most of these explanations imply that the seismically sampled domains contain important structural information that is distinct from the shear zones. The second set of examples stem from studies of outcrop-scale shear zones in upper

Hypogeous fungi at tree line in the Australian Alps

Treesearch

James M. Trappe; Andrew W Claridge

2006-01-01

The tree line of the continental Australian Alps yielded eighteen species of hypogeous fungi, all probably . forming ectomycorrhizae with Eucalyptus niphophila, the tree species characteristic of that habitat. Six of the species were undescribed. These collections represented six families and twelve genera: Boletaceae (with Chamonixia), Gallaceaceae...

A Hannibal's Treck Across The Alps: Geomorphological Analysis Of Sites Of Geoarchaeologicals Interest

NASA Astrophysics Data System (ADS)

Mahaney, William C.; Kalm, Volli; Dirszowsky, Randy W.; Milner, Michael W.; Sodhi, Rana; Beukens, Roelf; Dorn, Ron; Tricart, Pierre; Schwartz, Stéphane; Chamorro-Perez, Eva; Boccia, Sal; Barendregt, René W.; Krinsley, D. H.; Seaquist, E. R.; Merrick, David; Kapran, Barbara

A ~2200 year-old question related to Hannibal's invasion route across the Alps into Italia, has been argued by classicists without recovery of material evidence. A comparison of topographical descriptions in the ancient literature with environmental parameters in the Alps, attempted here for the first time, provides a database against which various pathways can be assessed. Identification of sites using geological, geomorphological, astronomical, chemical and petrological methods leads to the exclusion of certain transit points and targeting of others where geoarchaeological excavation might yield important evidence related to the military culture of ancient Carthage.

Thin visous sheet modelling of orogen scale deformation. The Eastern Alps in plan view

NASA Astrophysics Data System (ADS)

Robl, J.; Stuewe, K.

2003-04-01

We present first results of a new numerical model to describe the dynamic evolution of the eastern Alps in plan view on the orogen scale. We investigate the influence of boundary conditions, gravitational potential energy, rheology contrast of major tectonic units and internal structures on the deformation field. We aim at estimating the Argan number of the Eastern Alps and to calculate slip rates along big lineaments that represent the northern and southern border of the Austro-Alpine extrusion corridor. A further aim is to predict the position and the activity of major faults where they disappear below quartenary sediments. All calculation are perfomed with the mechanical finite element code BASIL that allows computation on a thin visous sheet. The starting conditons are controlled by the varying crustal thickness of the region and by the rheolgy of the Adriatic indenter in the south, the Bohemian massif in the north and the Eastern Alps inbetween. We assume that the Eastern Alps are fixed to the north and the west while the southern boundary moves northward at a rate of 6-8 mm /y. The geodynamic setting in the east changed over the last 5 my. While a roll back subduction zone beneath the Carparthian belt accompanied by extension, crustal thinning and basin formation controlled the deformation of the Eastern Alps until the Miocene. Later on subduction stopped and the overall stress field changed from extension to compression resulting in uplift of many basins and the lack sediments younger than Pliocene. This well known variation of plate tectonic scenarios over the last 5 my allows us to place tight constraints for the boundary conditions of our model. Although our work is only now in progress, we can report some promising results: some of the kinematics and mechaniscs predicted by our modelling are consistent with field observations of the structural geologists and geodeticists.

Ice-borne prehistoric finds in the Swiss Alps reflect Holocene glacier fluctuations

NASA Astrophysics Data System (ADS)

Grosjean, Martin; Suter, Peter J.; Trachsel, Mathias; Wanner, Heinz

2007-03-01

During the hot summer of 2003, reduction of an ice field in the Swiss Alps (Schnidejoch) uncovered spectacular archaeological hunting gear, fur, leather and woollen clothing and tools from four distinct windows of time: Neolithic Age (4900 to 4450 cal. yr BP), early Bronze Age (4100-3650 cal. yr BP), Roman Age (1st-3rd century AD), and Medieval times (8-9th century AD and 14-15th century AD). Transalpine routes connecting northern Italy with the northern Alps during these slots is consistent with late Holocene maximum glacier retreat. The age cohorts of the artefacts are separated which is indicative of glacier advances when the route was difficult and not used for transit. The preservation of Neolithic leather indicates permanent ice cover at that site from ca. 4900 cal. yr BP until AD 2003, implying that the ice cover was smaller in 2003 than at any time during the last 5000 years. Current glacier retreat is unprecedented since at least that time. This is highly significant regarding the interpretation of the recent warming and the rapid loss of ice in the Alps. Copyright

Petrologic and stable isotopic studies of a fossil hydrothermal system in ultramafic environment (Chenaillet ophicalcites, Western Alps, France): Processes of carbonate cementation

NASA Astrophysics Data System (ADS)

Lafay, Romain; Baumgartner, Lukas P.; Stephane, Schwartz; Suzanne, Picazo; German, Montes-Hernandez; Torsten, Vennemann

2017-12-01

The Late Jurassic Chenaillet ophiolitic complex (Western Alps) represents parts of an oceanic core-complex of the Liguria-Piemonte domain. A model for the origin and evolution of the Chenaillet ophicalcites based on textural and isotopic characterization is presented. The Chenaillet ophicalcites correspond to brecciated serpentinized peridotites that record seafloor shallow serpentinization at a minimum temperatures of 150 °C followed by authigenic carbonation. Carbonation starts with a network of micrometric to millimetric pre- or syn-clast formation calcite veins accompanied by a pervasive carbonation of residual olivine and serpentine inside the serpentinite mesh core. A matrix of small calcite (< 50 μm, 12 μm in average) cemented clasts after their individualization. Texture of the breccia, grain size distribution within the matrix, and chrysotile clusters support rapid cementation from a strongly oversaturated fluid due most likely to hydrothermal fluid cooling and decompression. Later fluids infiltrated by multiple crack formation and some dolomite locally formed along serpentinite-calcite interfaces. Carbonates have δ13C (VPDB) values that range between - 5‰ and + 0.4‰. The lower values were obtained for calcite within the serpentinite clasts. The δ18O (VSMOW) values have a range between + 11‰ and + 16‰ in carbonated clasts. The δ18O values in the matrix are fairly homogeneous with an average at + 12‰ and the late calcite veins have values between + 12.5 and + 15.5‰. These values suggest a relatively high temperature of formation for all the carbonates. Carbonates within clast are mainly characterized by a formation temperature in the range of 110 °C to 180 °C assuming a δ18O value of seawater of 0‰, the matrix forms at a temperature of ca. 165 °C. Late veins are characterized by a formation temperature ranging between 120and 155 °C. We propose a model where serpentinization is followed by discrete carbonation then brecciation and

White mica K-Ar geochronology of HP-UHP units in the Lago di Cignana area, western Alps, Italy: Tectonic implications for exhumation

NASA Astrophysics Data System (ADS)

Gouzu, Chitaro; Yagi, Koshi; Thanh, Ngo Xuan; Itaya, Tetsumaru; Compagnoni, Roberto

2016-04-01

High-pressure and ultra-high pressure (HP-UHP) blueschist- and eclogite-facies metabasaltic and metasedimentary rocks occur in four different tectonic units near Lago di Cignana, western Alps. We have determined K-Ar ages for white micas (matrix phengite and paragonite) from the Lago di Cignana UHP unit (LCU; 39-41 Ma); the lower and upper units of the Zermatt-Saas meta-ophiolite (LU and UU; 37-38 Ma and 38-41 Ma respectively), and the Combin unit (CU; 36-40 Ma). These K-Ar ages overlap with single-grain Ar-Ar plateau ages (36-42 Ma) previously determined for phengites from LCU metasediments. Matrix white micas have been severely deformed during exhumation, and their chemistries differ from those of micas included in garnet. Although individual mica grains in the matrix could have experienced different degrees of deformation which have reset their K-Ar systems, "bulk" white mica separates provide the average age of all the individual grains in the separate. The similarity of ages determined for white micas from the LCU, LU, UU and CU units, regardless of rock type and mineral species, suggests that these four units were metamorphosed together as part of a single metamorphic sequence in the Piemonte-Liguria paleosubduction zone and were subsequently exhumed together. However, present-day structural relationship among those units and the limited occurrence of UHP minerals in LCU suggests that the exhumation of LCU was more rapid than that for LU, UU and CU. The age gaps between the youngest value of white mica K-Ar ages in each unit and the inferred timing of the metamorphic peak (U-Pb age: 44 Ma) is 5, 7, 6 and 8 Myr for LCU, LU, UU and CU, respectively. These intervals are considerably shorter than that determined for the Sanbagawa HP metamorphic belt of Southwest Japan (> 31 Myr). The short interval observed for the Lago di Cignana units that we have studied is consistent with the model of rapid exhumation of the UHP-bearing metamorphic domain, suggesting the

Vulnerability and adaptation to water scarcity in the European Alps

NASA Astrophysics Data System (ADS)

Isoard, S.; McCallum, S.; Prutsch, A.; Benno Hain, B.; Schauser, I.

2009-04-01

The European Environment Agency (EEA) has recently undertaken a project addressing vulnerability and adaptation to water availability in the European Alps. Mountains are indeed one of the most vulnerable regions to climate change in Europe (EEA 2008, IPCC 2007).The Alps, in particular, can be presented as the ‘water towers' of Europe (the amount of water delivered by the Alps allocates 40% of EU consumption) where changes in water availability affect all socio-economical sectors. This therefore makes adaptation actions a regional topic with an outstanding European dimension. The specific objectives of the study were to highlight the importance of the Alps in their function as ‘water towers' for Europe and analyse the vulnerability of the Alpine Region with regard to impacts of climate change (but also to global change as a whole) focussing on water availability. Given the EU and regional policy background with regard to adaptation and water issues, the study assessed the possible needs, constraints and opportunities for adaptation to the adverse impacts for various sectors pending on water resources. Findings of this activity expanded the knowledge base, fed into the preparation of European Commission's 2009 White Paper and the Alpine Convention 2009 Report on the State of the Alps, and complemented other recent studies (e.g. OECD 2007, European Parliament Committee on Agriculture & Rural Development 2008). The method used for the study relied on the one hand on findings from recent key publications on climate change impacts (EEA 2008, IPCC 2007) and EU research projects (e.g. ClimChAlp, ProClim); on the other side it was based on selected case studies chosen within the four climatic regions of the eight Alpine countries for which an extensive series of interviews with local and regional stakeholders and decision makers has been undertaken. The interviewees had been directly involved in designing and implementing water availability-related adaptation measures

The AlpArray Seismic Network: status and operation

NASA Astrophysics Data System (ADS)

Hetényi, György; Molinari, Irene; Clinton, John; Kissling, Edi

2017-04-01

The AlpArray initiative (http://www.alparray.ethz.ch) is a large-scale European collaboration to study the entire Alpine orogen at high resolution and in 3D with a large variety of geoscientific methods. The core element of the initiative is an extensive and dense broadband seismological network, the AlpArray Seismic Network (AASN). Over 300 temporary stations complement the permanent seismological stations to ensure homogeneous coverage of the greater Alpine area. The AASN has officially started operation in January 2016 and is now complete on land. It is operated in a joint effort by a number of institutions from Austria, Bosnia-Herzegovina, Croatia, Czech Republic, France, Germany, Hungary, Italy, Slovakia and Switzerland. In the Ligurian Sea, a 32-station OBS campaign is planned from June 2017 until March 2018. This will complete the coverage of the greater Alpine area at an unprecedented resolution. In this poster we present the actual status of the deployment, the effort undertaken by the contributing groups, station performance, best practices, data management as well as often encountered challenges, and provide a meeting and discussion point during the conference.

Exhumation rates in the Gran Paradiso Massif (Western Alps) constrained by in situ U-Th-Pb dating of accessory phases (monazite, allanite and xenotime)

NASA Astrophysics Data System (ADS)

Manzotti, Paola; Bosse, Valérie; Pitra, Pavel; Robyr, Martin; Schiavi, Federica; Ballèvre, Michel

2018-03-01

Exhumation rates for high-pressure metamorphic rocks need to be carefully estimated to decipher tectonic processes in subduction/collision belts. In the Gran Paradiso Massif (Western Alps), the Money Unit crops out as a tectonic window below the Gran Paradiso Unit. According to previous studies, the Gran Paradiso and Money Units reached peak pressure conditions at 18 to 20 kbar, 480-520 °C and 17 to 18 kbar, 500-550 °C, respectively. This yields a maximum difference of 9 to 10 km in the subduction depth reached by these two units during the Alpine history. Thrusting of the Gran Paradiso Unit over the Money Unit led to the simultaneous development of the main foliation under the same metamorphic conditions ( 12.5 to 14.5 kbar and 530-560 °C) in both units. The thrust contact was subsequently folded and then both units were exhumed together. The relative timing of the growth and dissolution of the accessory phases was assessed by combining thermodynamic modelling with inclusion, textural and chemical (major and trace element) data from both major and accessory phases. The age of monazite constrained the high-pressure metamorphism in both the Gran Paradiso Unit and the Money Unit at 41.5 ± 0.3 and 42.0 ± 0.6 Ma, respectively. Allanite replacing monazite in the matrix has been dated at 32.7 ± 4.2 Ma. The late growth of xenotime associated with the crystallization of biotite pseudomorphs at the expense of garnet (at about 10 kbar) was dated at 32.3 ± 1.0 Ma. Our petrochronological data indicate about 10 m.y. between the peak pressure conditions and the crystallization of xenotime leading to an exhumation rate of the order of 2.2-5 mm/year. The new ages allow to better constrain the timing of the displacement of the thrust defining the lower boundary of the extruding wedge of eclogite-facies rocks.

Pre-Variscan evolution of the Western Tatra Mountains: new insights from U-Pb zircon dating.

PubMed

Burda, Jolanta; Klötzli, Urs

In situ LA-MC-ICP-MS U-Pb zircon geochronology combined with cathodoluminescence imaging were carried out to determine protolith and metamorphic ages of orthogneisses from the Western Tatra Mountains (Central Western Carpathians). The metamorphic complex is subdivided into two units (the Lower Unit and the Upper Unit). Orthogneisses of the Lower Unit are mostly banded, fine- to medium-grained rocks while in the Upper Unit varieties with augen structures predominate. Orthogneisses show a dynamically recrystallised mineral assemblage of Qz + Pl + Bt ± Grt with accessory zircon and apatite. They are peraluminous (ASI = 1.20-1.27) and interpreted to belong to a high-K calc-alkaline suite of a VAG-type tectonic setting. LA-MC-ICP-MS U-Pb zircon data from samples from both units, from crystals with oscillatory zoning and Th/U > 0.1, yield similar concordia ages of ca. 534 Ma. This is interpreted to reflect the magmatic crystallization age of igneous precursors. These oldest meta-magmatics so far dated in the Western Tatra Mountains could be linked to the fragmentation of the northern margin of Gondwana. In zircons from a gneiss from the Upper Unit, cores with well-developed oscillatory zoning are surrounded by weakly luminescent, low contrast rims (Th/U < 0.1). These yield a concordia age of ca. 387 Ma corresponding to a subsequent, Eo-Variscan, high-grade metamorphic event, connected with the formation of crustal-scale nappe structures and collision-related magmatism.

Investigations on socio economic indicators of French Alps ski industry from an explicit spatial modelling of managed snow on ski slopes

NASA Astrophysics Data System (ADS)

Spandre, Pierre; François, Hugues; Morin, Samuel; George-Marcelpoil, Emmanuelle; Lafaysse, Matthieu

2017-04-01

Investigations of the capacity of ski resorts to anticipate, cope with and recover from the impact of natural snow scarcity through snow management (grooming, snowmaking) have been realized in most of the major regions in terms of international ski offer although not in the French Alps hitherto. The present work therefore introduces an innovative approach for the investigation of socio economic implications of changes in snow conditions for the French Alps ski resorts based on a panel of 129 resorts representing 96% of the total French Alps ski lifts infrastructures. We integrated detailed spatial representations of ski resorts (including priority areas for snowmaking equipment) along with physically based snowpack modelling (including the physical impact of grooming and snowmaking). The viability of ski resorts was further adressed thanks to a commonly used rule based on the snow season duration at the village and ski lifts average elevations along with the development of original viability indicators of snow conditions in the French Alps ski resorts based on the specific periods for the economic success of winter sports: Christmas and February school holidays. Such indicators were correlated to the number of ski lifts tickets sales over the 2001 - 2014 period and proved to be relevant to investigate and predict the evolutions of ski lifts tickets sales under the current ski market conditions in the French Alps. Our results outlined the contrast of snow conditions between French Alps ski resorts, even when accounting for snow management, particularly regarding the geographical location of resorts (Southern versus Northern Alps), the size and related elevation range of ski resorts. Our physically based approach also allowed to compute the water and energy requirements for the production of Machine Made snow since the start of the development of snowguns in the French Alps. Our computations proved to be strongly correlated to the observed amounts of water from the

Adapting the ALP Model for Student and Institutional Needs

ERIC Educational Resources Information Center

Sides, Meredith

2016-01-01

With the increasing adoption of accelerated models of learning comes the necessary step of adapting these models to fit the unique needs of the student population at each individual institution. One such college adapted the ALP (Accelerated Learning Program) model and made specific changes to the target population, structure and scheduling, and…

Medical ethnobotany of the Albanian Alps in Kosovo.

PubMed

Mustafa, Behxhet; Hajdari, Avni; Krasniqi, Feriz; Hoxha, Esat; Ademi, Hatixhe; Quave, Cassandra L; Pieroni, Andrea

2012-01-28

Ethnobotanical studies are crucial in South-Eastern Europe for fostering local development and also for investigating the dynamics of Traditional Environmental Knowledge (TEK) related to plants in one of the most crucial European hotspots for biocultural diversity. The current medico-ethnobotanical survey was conducted in rural alpine communities in Kosovo. The aims of the study were twofold: 1) to document the state of TEK of medicinal plants in these communities; 2) to compare these findings with that of similar field studies previously conducted among local populations inhabiting the Montenegrin and Albanian side of the same Alpine range. Field research was conducted in 36 villages on the Kosovar side of the Albanian Alps. Snowball sampling techniques were used to recruit 91 elderly informants (≥ 50 years-old) for participation in semi-structured interviews and structured surveys regarding the use of the local flora for medicinal and food purposes. Standard ethnobotanical methods were employed and prior informed consent was obtained for all study participants. The uses of 98 plants species belonging to 39 families were recorded; the most quoted botanical families were Rosaceae, Asteraceae, and Lamiaceae. Mainly decoctions and infusions were quoted as folk medicinal preparations and the most common uses referred to gastrointestinal and respiratory disorders, as well as illnesses of the uro-genital system. Among the most uncommon medicinal taxa quoted by the informants, Carduus nutans L., Echinops bannaticus Rochel ex Schrad., and Orlaya grandiflora Hoffm. may merit phytochemical and phytopharmacological investigations.Comparison of the data with other ethnobotanical field studies recently conducted on the Albanian and Montenegrin sides of the same Alps has shown a remarkable link between the medical ethnobotany of Montenegrin and Kosovar side of the Albanian Alps. Moreover, folk uses of the most quoted wild medicinal taxa recorded in Kosovo often include those

Seismic source study of the Racha-Dzhava (Georgia) earthquake from aftershocks and broad-band teleseismic body-wave records: An example of active nappe tectonics

USGS Publications Warehouse

Fuenzalida, H.; Rivera, L.; Haessler, H.; Legrand, D.; Philip, H.; Dorbath, L.; McCormack, D.; Arefiev, S.; Langer, C.; Cisternas, A.

1997-01-01

The Racha-Dzhava earthquake (Ms = 7.0) that occurred on 1991 April 29 at 09:12:48.1 GMT in the southern border of the Great Caucasus is the biggest event ever recorded in the region, stronger than the Spitak earthquake (Ms = 6.9) of 1988. A field expedition to the epicentral area was organised and a temporary seismic network of 37 stations was deployed to record the aftershock activity. A very precise image of the aftershock distribution is obtained, showing an elongated cloud oriented N105??, with one branch trending N310?? in the western part. The southernmost part extends over 80 km, with the depth ranging from 0 to 15 km, and dips north. The northern branch, which is about 30 km long, shows activity that ranges in depth from 5 to 15 km. The complex thrust dips northwards. A stress-tensor inversion from P-wave first-motion polarities shows a state of triaxial compression, with the major principal axis oriented roughly N-S, the minor principal axis being vertical. Body-waveform inversion of teleseismic seismograms was performed for the main shock, which can be divided into four subevents with a total rupture-time duration of 22 s. The most important part of the seismic moment was released by a gentle northerly dipping thrust. The model is consistent with the compressive tectonics of the region and is in agreement with the aftershock distribution and the stress tensor deduced from the aftershocks. The focal mechanisms of the three largest aftershocks were also inverted from body-wave records. The April 29th (Ms = 6.1) and May 5th (Ms = 5.4) aftershocks have thrust mechanisms on roughly E-W-oriented planes, similar to the main shock. Surprisingly, the June 15th (Ms = 6.2) aftershock shows a thrust fault striking N-S. This mechanism is explained by the structural control of the rupture along the east-dipping geometry of the Dzirula Massif close to the Borzhomi-Kazbeg strike-slip fault. In fact, the orientation and shape of the stress tensor produce a thrust on a N

Fluid regimes during late stages of a continental collision: Physical, chemical, and stable isotope measurements of fluid inclusions in fissure quartz from a geotraverse through the Central Alps, Switzerland

NASA Astrophysics Data System (ADS)

Mullis, Josef; Dubessy, Jean; Poty, Bernard; O'Neil, James

1994-05-01

Fluid evolution during neo-alpine metamorphism during late stages of the continental collision between Europe and Africa was studied by analyzing fluid inclusions in alpine fissure quartz collected in forty-nine localities along a geotraverse through the Central Alps, Switzerland. The methods employed include microthermometry, micro-Raman spectroscopy, K/Na thermometry, and stable isotope analysis. Early fluid inclusions provide evidence of close to peak metamorphic temperatures of the late Tertiary or neo-alpine metamorphic event. Fluid composition evolved along the geotraverse from north to south as follows: higher hydrocarbons were dominant in the low- and medium-grade diagenetic zones, methane was the main volatile in the high-grade diagenetic and low-grade anchizone, water dominated in the highgrade anchizone and low-grade epizone, with CO2 > 10 mol% in the high-grade epizone and in the mesozone. Higher hydrocarbons and CH 4 were the products of kerogen maturation and cracking of preexisting petroleum. Large water supplies originated from the dehydration of cooler metasedimentary rocks that were overthrust by crystalline basements of the Lepontines, Aar, and Gotthard massifs. Carbon isotope analyses suggest that the CO 2 component was derived from oxidation of graphitic matter, especially in the vicinity of sulfate-bearing metasediments and from decarbonation reactions. In the Aar and Gotthard massifs as well as in the Helvetic Axen nappe and its underlying North Helvetic flysch, high fluid pressures prevailed and favored nappe transport. By contrast, in the southern Lepontine area, very low early fluid pressures were probably related to dry rocks and scarce metasediments, and to high geothermal gradients that resulted from intense uplift and erosion between 26 and 18 Ma. Retrograde fluid evolution was recorded by a succession of fluid inclusion populations in each alpine fissure. It was controlled by uplift and cooling and characterized by decreasing contents

Deformation partitioning and fabric development during shearing of felsic migmatites (Valpelline Series, NW Alps)

NASA Astrophysics Data System (ADS)

Pariani, Federico; Menegon, Luca; Bistacchi, Andrea; Malaspina, Nadia

2014-05-01

The relationships between partial melting and deformation in the continental lower crust are critical for understanding lithosphere rheology and the processes leading to melt segregation. In metapelitic rocks in the lower portions of the crust partial melting typically occurs via dehydration of biotite and is generally characterized by a negative volume change when garnet is produced as a peritectic phase. As a result, segregation of biotite-derived melt by fracturing resulting from dilational strain is not common. Hence segregation of biotite-derived melts in the lower crust is likely to be controlled by active deformation via creation of structural anisotropies (fabric), which define migration pathways from the grain-size to the kilometre scale. This study investigates the relations between deformation mechanisms of minerals, fabric development and grain- and meso-scale deformation partitioning in felsic migmatites. The study area is located in the Valpelline Series of the Dent Blanche Nappe in the north-western Alps, which represents a slice of pre-Alpine lower crust dominated by metapelitic migmatites (i.e. 'kinzigites' in the Alpine literature). The migmatites are stromatic and show a leucosome-melanosome interlayering defining the dominant foliation (S2), which forms along a sinistral shear zone at least 1 km thick and laterally continuous for at least 8 km. Ti-in biotite geothermometry, mineral inclusions in garnet, and literature data indicate that S2 formed at P, T conditions of 800-820°C, 0.4-0.7 GPa, during dehydration melting of biotite. The melanosomes have about 80 vol% of garnet + biotite + sillimanite and are very poor in quartz and feldspars, indicating almost complete removal of melt. Garnet forms slightly elongated grains wrapped by biotite and sillimanite layers. Compositional maps of the elongated garnet do not show any zonation. EBSD analysis indicates that the elongated garnets are actually clusters of individual grains with no internal

The lichens of the Alps – an annotated checklist

PubMed Central

Nimis, Pier Luigi; Hafellner, Josef; Roux, Claude; Clerc, Philippe; Helmut Mayrhofer; Martellos, Stefano; Bilovitz, Peter O.

2018-01-01

Abstract This is the first attempt to provide an overview of the lichen diversity of the Alps, one of the biogegraphically most important and emblematic mountain systems worldwide. The checklist includes all lichenised species, plus a set of non- or doubtfully lichenised taxa frequently treated by lichenologists, excluding non-lichenised lichenicolous fungi. Largely based on recent national or regional checklists, it provides a list of all infrageneric taxa (with synonyms) hitherto reported from the Alps, with data on their distribution in eight countries (Austria, France, Germany, Liechtenstein, Monaco, Italy, Slovenia, Switzerland) and in 42 Operational Geographic Units, mostly corresponding to administrative subdivisions within the countries. Data on the main substrates and on the altitudinal distribution are also provided. A short note points to the main ecological requirements of each taxon and/or to open taxonomic problems. Particularly poorly known taxa are flagged and often provided with a short description, to attract the attention of specialists. The total number of infrageneric taxa is 3,163, including 117 non- or doubtfully lichenised taxa. The richness of the lichen biota fairly well corresponds with the percent of the Alpine area occupied by each country: Austria (2,337 taxa), Italy (2,169), France (2,028), Switzerland (1,835), Germany (1,168), Slovenia (890) and Lichtenstein (152), no lichen having ever been reported from Monaco. The number of poorly known taxa is quite high (604, 19.1% of the total), which indicates that, in spite of the Alps being one of the lichenologically most studied mountain systems worldwide, much work is still needed to reach a satisfactory picture of their real lichen diversity. Thirteen new combinations are proposed in the genera Agonimia, Aspicilia, Bagliettoa, Bellemerea, Carbonea, Lepra, Miriquidica, Polysporina, Protothelenella, Pseudosagedia and Thelidium. PMID:29706791

French Alps, Mont Blanc, French/Italian Border

NASA Image and Video Library

1992-04-02

In this southeast looking view, Mont Blanc, on the French/Italian border, (48.0N, 4.5E) the highest mountain peak in all of Europe, is just below and right of center (below the end of the prominent valley of the Aosta River, in the center of the photo. The rivers flow out of the Alps into Italy toward Turin. Chamonix, the famous resort town and center of Alpine mountain climbing, lies in the valley just below Mont Blanc.

Tectono-metamorphic evolution of meta-ophiolitic units along Susa Valley (Italian Western Alps): new suggestions for the exhumation processes

NASA Astrophysics Data System (ADS)

Ghignone, Stefano; Borghi, Alessandro; Balestro, Gianni; Gattiglio, Marco

2017-04-01

In the inner Western Alps, meta-ophiolite units (i.e., the Piemonte Zone) show different stages of the tectono-metamorphic evolution, since the early phases of subduction to the latest exhumation steps. Tectono-metamorphic data collected through the meta-ophiolite units of the Piemonte Zone along the middle Susa Valley allowed to infer new ideas about the exhumation processes that developed in the (U)HP units. In this area, Zermatt-Saas-like meta-ophiolite unit (i.e., the eclogite-facies Internal Piemonte Zone, IPZ) are tectonically overlain by Combin-like ones (i.e., the blueschist-facies External Piemonte Zone, EPZ), through a thick shear zone (i.e., the Susa Shear Zone, SSZ). Metamorphic history was achieved by analyzing basic rocks (metabasalt and Fe-Ti metagabbro) and sedimentary rocks derived from reworking basic rocks in oceanic environment (basic sandstones and conglomerates, and ophiolitic breccia). Different P-T paths were inferred for IPZ and EPZ, according with mineral assemblages and realizations of pseudosections. In the IPZ, four tectono-metamorphic events, developed under variables metamorphic conditions, were recognized. The first (peak-P) event shows (U)HP conditions, defined by the occurrence of relic mineral assemblage (Grt I+ Omp I + Rt). The paragenesis is completed by Zo + Pg pseudomorphs, implying that Lws-eclogite facies were reached. The discovery in Grt (and Rt) relics inclusions of black euhedral pseudomorphs of disordered graphite, suggesting to be derived from original microdiamonds, agree with other petrologic constrains. The second event, marked by the Grt II + Omp II + Ph + Gln + Zo assemblage, developed under epidote-eclogite facies conditions. Following a retrograde and decompressional trajectory, the IPZ was then re-equilibrated under greenschist-facies conditions and a new assemblage (Ab + Chl + Mu + Czo + Ttn + Act) overprinted HP paragenesis. The last event is marked by a weak heating, with crystallization of Bt + Ep + Olig

Early Late Triassic Subduction in the Northern Branch of Neotethys?: Petrological and Paleontological Constraints from the middle Carnian basalts in the Lycian Nappes

NASA Astrophysics Data System (ADS)

Sayit, K.; Göncüoglu, M. C.; Tekin, U. K.

2015-12-01

The Lycian Nappes, SW Anatolia, are represented by a stack of thrust sheets derived from the northern branch of Neotethys (i.e. Izmir-Ankara Ocean) and the northern margin of the Tauride-Anatolide platform. The Turunç Unit, which is now preserved within a tectonic slice of the Lycian Nappes, includes among others the Neotethys-derived basalt blocks with pelagic intra-pillow carbonate infillings of middle Carnian age (early Late Triassic). Here, we focus on the geochemistry of the Turunç basalts to shed light into their petrogenetic evolution within the Neotethyan framework. Immobile trace element systematics indicate that the Turunç lavas are sub-alkaline basalts, with geochemical signatures resembling to those generated above subduction zones. Detailed examination of the Turunç volcanics reveals two chemical groups. Both groups are variably enriched in Th and La relative to Nb, and exhibit depleted Zr and Hf contents relative to N-MORB. Of the two groups, however, Group 2 is more enriched in Th, but with a similar Nb content, which results in higher Th/Nb ratios (0.21-0.27) compared to those of Group 1 (0.08-0.11). Both groups reflect similar REE systematics; they display marked enrichment in LREE relative to HREE ([La/Yb]N = 4.8-8.9). Trace element characteristics of the Turunç basalts indicate that their mantle source has been modified by slab-derived component(s). Taking into account that the Turunc Unit includes no continent-derived detritus, we suggest that the Turunç lavas represent fragments of a Late Triassic island arc formed on the Neotethyan oceanic lithosphere. This may further imply that the Neotethyan oceanic lithosphere had already been formed by the early Late Triassic, thus suggesting a pre-early Late Triassic oceanization of the northern branch of Neotethys.

Synthesis and effect of Ce and Mn co-doping on photoluminescence characteristics of Ca6AlP5O20:Eu novel phosphors.

PubMed

Shinde, K N; Dhoble, S J

2013-01-01

A series of Ca6AlP5O20 doped with rare earths (Eu and Ce) and co-doped (Eu, Ce and Eu,Mn) were prepared by combustion synthesis. Under Hg-free excitation, Ca6AlP5O20:Eu exhibited Eu(2+) (486 nm) emission in the blue region of the spectrum and under near Hg excitation (245 nm), Ca6AlP5O20:Ce phosphor exhibited Ce(3+) emission (357 nm) in the UV range. Photoluminescence (PL) peak intensity increased in Ca6AlP5O20:Eu,Ce and Ca6AlP5O20:Eu, Mn phosphors due to co-activators of Ce(3+) and Mn(2+) ions. As a result, these ions played an important role in PL emission in the present matrix. Ca6AlP5O20:Eu, Ce and Ca6AlP5O20:Eu, Mn phosphors provided energy transfer mechanisms via Ce(3+) → Eu(2+) and Eu(2+) → Mn(2+), respectively. Eu ions acted as activators and Ce ions acted as sensitizers. Ce emission energy was well matched with Eu excitation energy in the case of Ca6AlP5O20:Eu, Ce and Eu ions acted as activators and Mn ions acted as sensitizers in Ca6AlP5O20:Eu, Mn. This study included synthesis of new and efficient phosphate phosphors. The impact of doping and co-doping on photoluminescence properties and energy transfer mechanisms were investigated and we propose a feasible interpretation. Copyright © 2012 John Wiley & Sons, Ltd.

Analog Modeling of the Interplay between Subduction and Lateral Extrusion in the European Alps

NASA Astrophysics Data System (ADS)

van Gelder, I. E.; Willingshofer, E.; Sokoutis, D.

2014-12-01

In the European Alps lateral extrusion is traditionally viewed as a lithospheric scale process that is related to northward indentation of a weak orogenic wedge (the eastern Alps) by a rigid indenter in upper plate position (the Adriatic plate). Critical for the efficiency of the extrusion process is the presence of a 'free boundary' at high angle to the indentation direction. The 'free boundary' in the eastern Alps is the result of the eastward extending Pannonian realm synchronous to indentation. However, indentation has become debatable as recent high-resolution tomography suggests that the Adriatic mantle lithosphere subducted under the extruding Alps. These findings raise first order questions related to: (a) the partitioning of deformation between lateral extrusion of the upper plate and coeval subduction of Adria, (b) the rheology of the lower and upper plates, and (c) the rheology of the plate contact controlling the amount of extrusion on the upper plate vs. accretion on the lower plate.In this analog modeling study, we couple for the first time lateral extrusion tectonics to subduction of the lower plate; thus, extrusion taking place in the upper plate. Within the lithospheric scale models, the lithospheres of the two plates are weakly coupled along an inclined boundary and have contrasting mantle lithosphere strength (stronger in the subducting plate). The interplay of extrusion vs subduction is inferred by varying the mechanical boundary conditions, e.g. the degree of resistance at the 'unconstrained' margin, the strength contrast between the upper and the lower plates and the width of the indented region.The experimental results emphasize that extrusion in the eastern Alps is compatible with coeval subduction of the Adriatic plate. The first experimental series suggests that the following mechanical conditions play a key role in the interplay between extrusion and subduction: (a) the extruding plate is weaker than the subducting plate, (b) the plate

On-demand Simulation of Atmospheric Transport Processes on the AlpEnDAC Cloud

NASA Astrophysics Data System (ADS)

Hachinger, S.; Harsch, C.; Meyer-Arnek, J.; Frank, A.; Heller, H.; Giemsa, E.

2016-12-01

The "Alpine Environmental Data Analysis Centre" (AlpEnDAC) develops a data-analysis platform for high-altitude research facilities within the "Virtual Alpine Observatory" project (VAO). This platform, with its web portal, will support use cases going much beyond data management: On user request, the data are augmented with "on-demand" simulation results, such as air-parcel trajectories for tracing down the source of pollutants when they appear in high concentration. The respective back-end mechanism uses the Compute Cloud of the Leibniz Supercomputing Centre (LRZ) to transparently calculate results requested by the user, as far as they have not yet been stored in AlpEnDAC. The queuing-system operation model common in supercomputing is replaced by a model in which Virtual Machines (VMs) on the cloud are automatically created/destroyed, providing the necessary computing power immediately on demand. From a security point of view, this allows to perform simulations in a sandbox defined by the VM configuration, without direct access to a computing cluster. Within few minutes, the user receives conveniently visualized results. The AlpEnDAC infrastructure is distributed among two participating institutes [front-end at German Aerospace Centre (DLR), simulation back-end at LRZ], requiring an efficient mechanism for synchronization of measured and augmented data. We discuss our iRODS-based solution for these data-management tasks as well as the general AlpEnDAC framework. Our cloud-based offerings aim at making scientific computing for our users much more convenient and flexible than it has been, and to allow scientists without a broad background in scientific computing to benefit from complex numerical simulations.

Spodumene bearing pegmatites in the Austroalpine unit (Eastern Alps): Distribution and new geochronological data

NASA Astrophysics Data System (ADS)

Ilickovic, Tanja; Schuster, Ralf; Mali, Heinrich; Petrakakis, Konstantin; Schedl, Albert

2017-04-01

In the Austroalpine unit of the Eastern Alps spodumene bearing pegmatites occur heterogeneously distributed over an E-W distance of more than 400 km. They are usually associated with barren pegmatites which crystallisized in Permian time. There a two schools of thought about the genesis of the spodumene bearing pegmatites: Economic geologists bring forward the argument that these pegmatites only develop by fractionation of granitic parent plutons, whereas metamorphic petrologists consider that the barren pegmatites and even some highly fractionated pegmatites are products of anatexis of metapelitic country rocks. In the first case the virtual absence of co-genetic fertile granites in the Austroalpine units render the model problematic, whereas in the second case the formation of suitable Li-enriched pegmatitic melts is not yet understood. A new understanding of the Austroalpine basement through geological mapping and geochronological and geochemical investigations during the past few years gives the opportunity to reinvestigate this problem: In Permian time the Austroalpine unit was affected by lithospheric extension, causing basaltic underplating, high temperature / low pressure metamorphism and intense magmatic activity. The Permian P-T-t path is characterized by heating at slightly decreasing pressure. In an ongoing project additional spodumene bearing pegmatites have been discovered and some of them show temporal and spatial relations to relatively small leucogranitic bodies. New Sm/Nd data prove a Permian age for spodumene bearing pegmatites and leucogranites supporting a genetic relation with the barren pegmatites. Mapping revealed certain relations of pegmatites and distinct country rocks. Units of migmatitic mica schists with lots of interlayed barren pegmatites represent areas with aborted melt generation. In some places the melts accumulate forming inhomogeneous leucogranitic bodies. Examples are the Martell granite (South Tyrol) as well as leucoganites

Mountaineering accidents in the European Alps: have the numbers increased in recent years?

PubMed

Lischke, V; Byhahn, C; Westphal, K; Kessler, P

2001-01-01

Media reports convey the impression that the incidence of fatal accidents in the European Alps has increased. Because more specific data are lacking, we analyzed available data from the mountain rescue services in Germany, Austria, southern Tirol, Zermatt/Switzerland, and Chamonix/France from 1987 until 1997. Information was gathered from the annual reports of the Austrian Mountain Rescue Service, the Swiss Alpine Club Rescue Station in Zermatt, the Mountain Rescue Service of the Southern Tirol Alpine Club, the Mountain Rescue Service of the Bavarian Red Cross, and the Department of Mountain Medicine and Traumatology from the Hospital in Chamonix. Although the total number of rescue missions and injured alpinists increased significantly during the period, the number of fatalities retrieved during such rescue missions showed no significant increase. Even taking into account the varying definitions of "mountain accident" used in these countries, available data from the analyzed areas of the European Alps do not demonstrate a drastic increase in the number of fatalities. In the future, data concerning mountain accidents in the European Alps should be monitored according to standard definitions and stored by the International Commission for Alpine Rescue.

Active and fossil mantle flows in the western Alpine region unravelled by seismic anisotropy analysis and high-resolution P wave tomography

NASA Astrophysics Data System (ADS)

Salimbeni, Simone; Malusà, Marco G.; Zhao, Liang; Guillot, Stéphane; Pondrelli, Silvia; Margheriti, Lucia; Paul, Anne; Solarino, Stefano; Aubert, Coralie; Dumont, Thierry; Schwartz, Stéphane; Wang, Qingchen; Xu, Xiaobing; Zheng, Tianyu; Zhu, Rixiang

2018-04-01

The anisotropy of seismic velocities in the mantle, when integrated with high-resolution tomographic models and geologic information, can be used to detect active mantle flows in complex plate boundary areas, providing new insights on the impact of mantle processes on the topography of mountain belts. Here we use a densely spaced array of temporary broadband seismic stations to analyze the seismic anisotropy pattern of the western Alpine region, at the boundary between the Alpine and Apenninic slabs. Our results are supportive of a polyphase development of anisotropic mantle fabrics, possibly starting from the Jurassic to present. Geophysical data presented in this work, and geologic evidence taken from the literature, indicate that: (i) fossil fabrics formed during Tethyan rifting may be still preserved within the Alpine and Apenninic slabs; (ii) mantle deformation during Apenninic slab rollback is not compensated by a complete toroidal flow around the northern tip of the retreating slab; (iii) the previously observed continuous trend of anisotropy fast axes near-parallel to the western Alpine arc is confirmed. We observe that this arc-parallel trend of fast axes is located in correspondence to a low velocity anomaly in the European upper mantle, beneath regions of the Western and Ligurian Alps showing the highest uplift rates. We propose that the progressive rollback of the Apenninic slab, in the absence of a counterclockwise toroidal flow at its northern tip, induced a suction effect at the scale of the supraslab mantle. The resulting mantle flow pattern was characterized by an asthenospheric counterflow at the rear of the unbroken Western Alps slab and around its southern tip, and by an asthenospheric upwelling, mirrored by low P wave velocities, that would have favored the topographic uplift of the Alpine belt from the Mont Blanc to the Mediterranean sea.

The AlpArray Seismic Network: A Large-Scale European Experiment to Image the Alpine Orogen

NASA Astrophysics Data System (ADS)

Hetényi, György; Molinari, Irene; Clinton, John; Bokelmann, Götz; Bondár, István; Crawford, Wayne C.; Dessa, Jean-Xavier; Doubre, Cécile; Friederich, Wolfgang; Fuchs, Florian; Giardini, Domenico; Gráczer, Zoltán; Handy, Mark R.; Herak, Marijan; Jia, Yan; Kissling, Edi; Kopp, Heidrun; Korn, Michael; Margheriti, Lucia; Meier, Thomas; Mucciarelli, Marco; Paul, Anne; Pesaresi, Damiano; Piromallo, Claudia; Plenefisch, Thomas; Plomerová, Jaroslava; Ritter, Joachim; Rümpker, Georg; Šipka, Vesna; Spallarossa, Daniele; Thomas, Christine; Tilmann, Frederik; Wassermann, Joachim; Weber, Michael; Wéber, Zoltán; Wesztergom, Viktor; Živčić, Mladen

2018-04-01

The AlpArray programme is a multinational, European consortium to advance our understanding of orogenesis and its relationship to mantle dynamics, plate reorganizations, surface processes and seismic hazard in the Alps-Apennines-Carpathians-Dinarides orogenic system. The AlpArray Seismic Network has been deployed with contributions from 36 institutions from 11 countries to map physical properties of the lithosphere and asthenosphere in 3D and thus to obtain new, high-resolution geophysical images of structures from the surface down to the base of the mantle transition zone. With over 600 broadband stations operated for 2 years, this seismic experiment is one of the largest simultaneously operated seismological networks in the academic domain, employing hexagonal coverage with station spacing at less than 52 km. This dense and regularly spaced experiment is made possible by the coordinated coeval deployment of temporary stations from numerous national pools, including ocean-bottom seismometers, which were funded by different national agencies. They combine with permanent networks, which also required the cooperation of many different operators. Together these stations ultimately fill coverage gaps. Following a short overview of previous large-scale seismological experiments in the Alpine region, we here present the goals, construction, deployment, characteristics and data management of the AlpArray Seismic Network, which will provide data that is expected to be unprecedented in quality to image the complex Alpine mountains at depth.

Effect of slope failures on river-network pattern: A river piracy case study from the flysch belt of the Outer Western Carpathians

NASA Astrophysics Data System (ADS)

Baroň, Ivo; Bíl, Michal; Bábek, Ondřej; Smolková, Veronika; Pánek, Tomáš; Macur, Lukáš

2014-06-01

Landslides are important geomorphic agents in various mountainous settings. We document here a case of river piracy from the upper part of the Malá Brodská Valley in the Vsetínské Mts., Czech Republic (Rača Unit of the flysch Magura Group of Nappes, flysch belt of the Outer Western Carpathians) controlled by mass movement processes. Based on the field geological, geomorphological and geophysical data, we found out that the landslide accumulations pushed the more active river of out of two subparallel river channels with different erosion activity westwards and forced intensive lateral erosion towards the recently abandoned valley. Apart from the landslide processes, the presence of the N-striking fault, accentuated by higher flow rates of the eastern channel as a result of its larger catchment area, were the most critical factors of the river piracy. As a consequence of the river piracy, intensive retrograde erosion in the elbow of capture and also within the upper portion of the western catchment occurred. Deposits of two landslide dams document recent minimum erosion rates to be 18.8 mm.ky- 1 in the western (captured) catchment, and 3.6 mm.ky- 1 in the eastern catchment respectively. The maximum age of the river piracy is estimated to be of the late Glacial and/or the early Holocene.

Average snowcover density values in Eastern Alps mountain

NASA Astrophysics Data System (ADS)

Valt, M.; Moro, D.

2009-04-01

The Italian Avalanche Warning Services monitor the snow cover characteristics through networks evenly distributed all over the alpine chain. Measurements of snow stratigraphy and density are very frequently performed with sampling rates of 1 -2 times per week. Snow cover density values are used to compute the dimensions of the building roofs as well as to design avalanche barriers. Based on the measured snow densities the Electricity Board can predict the amount of water resources deriving from snow melt in high relieves drainage basins. In this work it was possible to compute characteristic density values of the snow cover in the Eastern Alps using the information contained in the database from the ARPA (Agenzia Regionale Protezione Ambiente)-Centro Valanghe di Arabba, and Ufficio Valanghe- Udine. Among the other things, this database includes 15 years of stratigraphic measurements. More than 6,000 snow stratigraphic logs were analysed, in order to derive typical values as for geographical area, altitude, exposure, snow cover thickness and season. Computed values were compared to those established by the current Italian laws. Eventually, experts identified and evaluated the correlations between the seasonal variations of the average snow density and the variations related to the snowfall rate in the period 1994-2008 in the Eastern Alps mountain range

Alps, Carpathians and Dinarides-Hellenides: about plates, micro-plates and delaminated crustal blocks

NASA Astrophysics Data System (ADS)

Schmid, Stefan

2014-05-01

Before the onset of Europe-Africa continental collision in the Dinarides-Hellenides (around 60Ma) and in the Alps and Western Carpathians (around 35 Ma), and at a large scale, the dynamics of orogenic processes in the Mediterranean Alpine chains were governed by Europe-Africa plate convergence leading to the disappearance of large parts of intervening oceanic lithosphere, i.e. the northern branch of Neotethys along the Sava-Izmir-Ankara suture and Alpine Tethys along the Valais-Magura suture (Schmid et al. 2008). In spite of this, two major problems concerning the pre-collisional stage are still poorly understood: (1) by now we only start to understand geometry, kinematics and dynamics of the along-strike changes in the polarity of subduction between Alps-Carpathians and Dinarides-Hellenides, and (2) it is not clear yet during exactly which episodes and to what extent intervening rifted continental fragments such as, for example, Iberia-Briançonnais, Tisza, Dacia, Adria-Taurides moved independently as micro-plates, and during which episodes they remained firmly attached to Europa or Africa from which they broke away. As Europe-Africa plate convergence slowed down well below 1 cm/yr at around 30 Ma ago these pre-collisional processes driven by plate convergence on a global scale gave way to more local processes of combined roll-back and crustal delamination in the Pannonian basin of the Carpathian embayment and in the Aegean (as well as in the Western Mediterranean, not discussed in this contribution). In the case of the Carpathian embayment E-directed roll back totally unrelated to Europe-Africa N-S-directed convergence, started at around 20 Ma ago, due to the presence relict oceanic lithosphere in the future Pannonian basin that remained un-subducted during collision. Due to total delamination of the crust from the eastward rolling back European mantle lithosphere the anticlockwise rotating ALCAPA crustal block, consisting of Eastern Alps and Western Carpathian

Variation trend of snowfall in the Kamikochi region of the Japanese Alps

NASA Astrophysics Data System (ADS)

Suzuki, K.

2017-12-01

The Japanese Alps experience exceptionally heavy snowfall, extreme even by global standards, and in spring and summer the melting snow becomes a valuable water resource. The snow effectively acts as a natural dam when it accumulates in watersheds during winter. However, there have been no observations of the amount of snow in high-altitude regions of Japan. Therefore, we cannot discuss the effect of global warming on the change in the amount of snow in these regions based on direct observation data. We were, however, able to obtain climatic and hydrologic data for high-altitude sites in the Japanese Alps, and discuss the variations in these conditions in the Kamikochi region (altitude 1490 m-3190 m) of the Japanese Alps over a 68-year period using these observed data. No long-term trends are observed in the annual mean, maximum, or minimum temperatures at Taisho-ike from 1945 to 2012; the total annual precipitation shows a statistically significant decreasing trend. The annual total snowfall at Taisho-ike from 1969 to 2012 shows a statistically significant increasing trend. The annual total runoff of the Azusa River from 1945 to 2012 shows a statistically significant increasing trend, as does the snowmelt runoff to the river (which occurs from May to July). We can thus conclude that the annual snowfall in the Azusa River catchment has increased in recent years.

Intra-continental subduction and contemporaneous lateral extrusion of the upper plate: insights into Alps-Adria interactions

NASA Astrophysics Data System (ADS)

van Gelder, Inge; Willingshofer, Ernst; Sokoutis, Dimitrios; Cloetingh, Sierd

2017-04-01

A series of physical analogue experiments were performed to simulate intra-continental subduction contemporaneous with lateral extrusion of the upper plate to study the interferences between these two processes at crustal levels and in the lithospheric mantle. The lithospheric-scale models are specifically designed to represent the collision of the Adriatic microplate with the Eastern Alps, simulated by an intra-continental weak zone to initiate subduction and a weak confined margin perpendicular to the direction of convergence in order to allow for extrusion of the lithosphere. The weak confined margin is the analog for the opening of the Pannonian back-arc basin adjacent to the Eastern Alps with the direction of extension perpendicular to the strike of the orogen. The models show that intra-continental subduction and coeval lateral extrusion of the upper plate are compatible processes. The obtained deformation structures within the extruding region are similar compared to the classical setup where lateral extrusion is provoked by lithosphere-scale indentation. In the models a strong coupling across the subduction boundary allows for the transfer of abundant stresses to the upper plate, leading to laterally varying strain regimes that are characterized by crustal thickening near a confined margin and dominated by lateral displacement of material near a weak lateral confinement. During ongoing convergence the strain regimes propagate laterally, thereby creating an area of overlap characterized by transpression. In models with oblique subduction, with respect to the convergence direction, less deformation of the upper plate is observed and as a consequence the amount of lateral extrusion decreases. Additionally, strain is partitioned along the oblique plate boundary leading to less subduction in expense of right lateral displacement close to the weak lateral confinement. Both oblique and orthogonal subduction models have a strong resemblance to lateral extrusion

Medical ethnobotany of the Albanian Alps in Kosovo

PubMed Central

2012-01-01

Background Ethnobotanical studies are crucial in South-Eastern Europe for fostering local development and also for investigating the dynamics of Traditional Environmental Knowledge (TEK) related to plants in one of the most crucial European hotspots for biocultural diversity. The current medico-ethnobotanical survey was conducted in rural alpine communities in Kosovo. The aims of the study were twofold: 1) to document the state of TEK of medicinal plants in these communities; 2) to compare these findings with that of similar field studies previously conducted among local populations inhabiting the Montenegrin and Albanian side of the same Alpine range. Methods Field research was conducted in 36 villages on the Kosovar side of the Albanian Alps. Snowball sampling techniques were used to recruit 91 elderly informants (≥ 50 years-old) for participation in semi-structured interviews and structured surveys regarding the use of the local flora for medicinal and food purposes. Standard ethnobotanical methods were employed and prior informed consent was obtained for all study participants. Results and Conclusion The uses of 98 plants species belonging to 39 families were recorded; the most quoted botanical families were Rosaceae, Asteraceae, and Lamiaceae. Mainly decoctions and infusions were quoted as folk medicinal preparations and the most common uses referred to gastrointestinal and respiratory disorders, as well as illnesses of the uro-genital system. Among the most uncommon medicinal taxa quoted by the informants, Carduus nutans L., Echinops bannaticus Rochel ex Schrad., and Orlaya grandiflora Hoffm. may merit phytochemical and phytopharmacological investigations. Comparison of the data with other ethnobotanical field studies recently conducted on the Albanian and Montenegrin sides of the same Alps has shown a remarkable link between the medical ethnobotany of Montenegrin and Kosovar side of the Albanian Alps. Moreover, folk uses of the most quoted wild medicinal

The impact of overgrazing on dung beetle diversity in the Italian Maritime Alps.

PubMed

Negro, Matteo; Rolando, Antonio; Palestrini, Claudia

2011-10-01

Dung beetles (Coleoptera: Scarabaeidae) are undoubtedly the most typical and ecologically relevant insects of grazed alpine habitats because they provide valuable ecological services such as biological pest control and soil fertilization. Despite the great ecological contribution of these insects to pasture ecosystem functioning, little is known about their direct or indirect relationships with pastoral activities. The main aim of the study was to assess whether dung beetle diversity was influenced by different intensities of cattle grazing. Dung beetle communities of two adjacent alpine valleys within the Maritime Alps Natural Park (north-western Italian Alps), representing overgrazed and ungrazed pastures, were studied by pitfall trapping. A hierarchical design (three levels: valleys, transects, and replicates) was established for additive partitioning of γ-diversity and Indicator Species Analysis. Evenness and Shannon diversity were significantly higher at the ungrazed than at the overgrazed site because abundances were much more evenly distributed at the former than at the latter site (where one species was dominant over all the others). Dung beetle abundance and species richness of the overgrazed graminaceous pasture vegetation types were in most cases significantly lower than those of the ungrazed nongraminaceous vegetation type. In the additive partitioning of γ -diversity analysis relative to the whole study area, the randomization procedure indicated that the contribution of β to γ-diversity was significantly different from that expected by chance, suggesting that one or more environmental factors has intervened to change the partition of total diversity in the system considered. The analysis of the preferences and fidelity of species (Indicator Species Analysis) showed that only one species chose overgrazed pastures; all the others positively selected the ungrazed site, or the only ungrazed pasture vegetation type (Rumicetum alpini Beger) occurring at

Statistical downscaling of regional climate scenarios for the French Alps : Impacts on snow cover

NASA Astrophysics Data System (ADS)

Rousselot, M.; Durand, Y.; Giraud, G.; Mérindol, L.; Déqué, M.; Sanchez, E.; Pagé, C.; Hasan, A.

2010-12-01

Mountain areas are particularly vulnerable to climate change. Owing to the complexity of mountain terrain, climate research at scales relevant for impacts studies and decisive for stakeholders is challenging. A possible way to bridge the gap between these fine scales and those of the general circulation models (GCMs) consists of combining high-resolution simulations of Regional Climate Models (RCMs) to statistical downscaling methods. The present work is based on such an approach. It aims at investigating the impacts of climate change on snow cover in the French Alps for the periods 2021-2050 and 2071-2100 under several IPCC hypotheses. An analogue method based on high resolution atmospheric fields from various RCMs and climate reanalyses is used to simulate local climate scenarios. These scenarios, which provide meteorological parameters relevant for snowpack evolution, subsequently feed the CROCUS snow model. In these simulations, various sources of uncertainties are thus considered (several greenhouse gases emission scenarios and RCMs). Results are obtained for different regions of the French Alps at various altitudes. For all scenarios, temperature increase is relatively uniform over the Alps. This regional warming is larger than that generally modeled at the global scale (IPCC, 2007), and particularly strong in summer. Annual precipitation amounts seem to decrease, mainly as a result of decreasing precipitation trends in summer and fall. As a result of these climatic evolutions, there is a general decrease of the mean winter snow depth and seasonal snow duration for all massifs. Winter snow depths are particularly reduced in the Northern Alps. However, the impact on seasonal snow duration is more significant in the Southern and Extreme Southern Alps, since these regions are already characterized by small winter snow depths at low elevations. Reference : IPCC (2007a). Climate change 2007 : The physical science basis. Contribution of working group I to the

ALPS: the Dark Matter Generator (coming in 2019)

NASA Astrophysics Data System (ADS)

Barke, Simon; Bush, Zachary; Baum, Claire; Hollis, Hal; Mueller, Guido; Tanner, David

2017-01-01

Very promising dark matter candidates are axion-like particles: sub-eV particles that are expected to (weakly) interact with photons in the presence of a static electric or magnetic field. This interaction can turn photons into axions and back into photons. Hence, in order to generate axions, we will set up a 100 meter long Fabry-Perot cavity that can hold a 150,000 watt laser field and have a 5.3 tesla magnetic field along the entire length. If the theory holds up, a fraction of the photons should transform into relativistic axions. These axions would then propagate through any optical barrier and enter a matched cavity that is situated within an identical magnetic field. Here, some of the axions should turn back into photons of equal energy. Thus these photons resonate in the otherwise empty cavity where they can be detected. It is unknown if axion-like particles exist in the targeted mass range. However, the ALPS detection principle is very convenient because we will know the exact energy of the regenerated photons beforehand thus making a detection much easier.The final stage of the ALPS experiment will be completed by 2019 at the German Electron Synchrotron (DESY) site in Hamburg, Germany. This work is supported by grants from the Heising-Simons Foundation and the National Science Foundation.

Anatomy of an ancient subduction interface at 40 km depth: Insights from P-T-t-d data, and geodynamic implications (Dent Blanche, Western Alps)

NASA Astrophysics Data System (ADS)

Angiboust, Samuel; Glodny, Johannes; Oncken, Onno; Chopin, Christian

2014-05-01

An exhumed metamorphic suture zone over 40 km long is exposed in the Dent Blanche Region of the Western Alps belt, along the Swiss-Italian border. In this region, the metasediment-bearing ophiolitic remnants of the Liguro-Piemontese ocean (Tsaté complex) are overthrusted by a continental, km-sized complex (Dent Blanche Tectonic System: DBTS) of Austro-Alpine affinity. The DBTS represents a strongly deformed composite terrane with independent tectonic slices of continental and oceanic origin. In order to better understand the nature and the geodynamic meaning of the shear zone at the base of the DBTS (Dent Blanche Thrust, DBT) we re-evaluated the pressure-temperature-time-deformation (P-T-t-d) history of these two units using modern thermobarometric tools, Rb/Sr deformation ages and field relationships. Our results show that the Tsaté complex is formed by a stack of km-thick calcschists-bearing tectonic slices, having experienced variable maximum burial temperatures of between 360°C and 490°C at depths of ca. 25-40 km, between 41 Ma and 37 Ma. The Arolla gneissic mylonites constituting the base of the DBTS experienced a continuous record of protracted high-pressure (12-14 kbar), top-to-NW D1 deformation at 450-500°C between 43 and 55 Ma. Some of these primary, peak metamorphic fabrics have been sheared (top-to-SE D2) and backfolded during exhumation and collisional overprint (20 km depth, 35-40 Ma) leading to the regional greenschist facies retrogression particularly prominent within Tsaté metasediments. The final juxtaposition of the DBTS with the Tsaté complex occurred between 350 and 500°C during this later, exhumation-related D2 event. Although some exhumation-related deformation partially reworked D1 primary features, we emphasize that the DBT can be viewed as a remnant of the Alpine early Eocene blueschist-facies subduction interface region. The DBT therefore constitutes the deeper equivalent of some shallower portions of the Alpine subduction

ALP gene expression in cDNA samples from bone tissue engineering using a HA/TCP/Chitosan scaffold

NASA Astrophysics Data System (ADS)

Stephanie, N.; Katarina, H.; Amir, L. R.; Gunawan, H. A.

2017-08-01

This study examined the potential use of hydroxyapatite (HA)/tricalcium phosphate (TCP)/Chitosan as a bone tissue engineering scaffold. The potential for using HA/TCP/chitosan as a scaffold was analyzed by measuring expression of the ALP osteogenic gene in cDNA from bone biopsies from four Macaque nemestrina. Experimental conditions included control (untreated), treatment with HA/TCP 70:30, HA/TCP 50:50, and HA/TCP/chitosan. cDNA samples were measured quantitively with Real-Time PCR (qPCR) and semi-quantitively by gel electrophoresis. There were no significant differences in ALP gene expression between treatment subjects after two weeks, but the HA/TCP/chitosan treatment gave the highest level of expression after four weeks. The scaffold using the HA/TCP/chitosan combination induced a higher level of expression of the osteogenic gene ALP than did scaffold without chitosan.

Immediate and delayed signal of slab breakoff in Oligo/Miocene Molasse deposits from the European Alps

PubMed Central

Schlunegger, Fritz; Castelltort, Sébastien

2016-01-01

High-resolution 32–20 Ma-old stratigraphic records from the Molasse foreland basin situated north of the Alps, and Gonfolite Lombarda conglomerates deposited on the southern Alpine margin, document two consecutive sedimentary responses - an immediate and delayed response - to slab breakoff beneath the central Alps c. 32–30 Ma ago. The first signal, which occurred due to rebound and surface uplift in the Alps, was a regional and simultaneous switch from basin underfill to overfill at 30 Ma paired with shifts to coarse-grained depositional environments in the foreland basin. The second signal, however, arrived several million years after slab breakoff and was marked by larger contributions of crystalline clasts in the conglomerates, larger clast sizes, larger sediment fluxes and shifts to more proximal facies. We propose that this secondary pulse reflects a delayed whiplash-type erosional response to surface uplift, where erosion and sediment flux became amplified through positive feedbacks once larger erosional thresholds of crystalline bedrock were exceeded. PMID:27510939

Bacterial Composition and Survival on Sahara Dust Particles Transported to the European Alps

PubMed Central

Meola, Marco; Lazzaro, Anna; Zeyer, Josef

2015-01-01

Deposition of Sahara dust (SD) particles is a frequent phenomenon in Europe, but little is known about the viability and composition of the bacterial community transported with SD. The goal of this study was to characterize SD-associated bacteria transported to the European Alps, deposited and entrapped in snow. During two distinct events in February and May 2014, SD particles were deposited and promptly covered by falling snow, thus preserving them in distinct ochre layers within the snowpack. In June 2014, we collected samples at different depths from a snow profile at the Jungfraujoch (Swiss Alps; 3621 m a.s.l.). After filtration, we performed various microbiological and physicochemical analyses of the snow and dust particles therein that originated in Algeria. Our results show that bacteria survive and are metabolically active after the transport to the European Alps. Using high throughput sequencing, we observed distinct differences in bacterial community composition and structure in SD-layers as compared to clean snow layers. Sporulating bacteria were not enriched in the SD-layers; however, phyla with low abundance such as Gemmatimonadetes and Deinococcus-Thermus appeared to be specific bio-indicators for SD. Since many members of these phyla are known to be adapted to arid oligotrophic environments and UV radiation, they are well suited to survive the harsh conditions of long-range airborne transport. PMID:26733988

Powered mobility intervention: understanding the position of tool use learning as part of implementing the ALP tool.

PubMed

Nilsson, Lisbeth; Durkin, Josephine

2017-10-01

To explore the knowledge necessary for adoption and implementation of the Assessment of Learning Powered mobility use (ALP) tool in different practice settings for both adults and children. To consult with a diverse population of professionals working with adults and children, in different countries and various settings; who were learning about or using the ALP tool, as part of exploring and implementing research findings. Classical grounded theory with a rigorous comparative analysis of data from informants together with reflections on our own rich experiences of powered mobility practice and comparisons with the literature. A core category learning tool use and a new theory of cognizing tool use, with its interdependent properties: motivation, confidence, permissiveness, attentiveness and co-construction has emerged which explains in greater depth what enables the application of the ALP tool. The scientific knowledge base on tool use learning and the new theory conveys the information necessary for practitioner's cognizing how to apply the learning approach of the ALP tool in order to enable tool use learning through powered mobility practice as a therapeutic intervention in its own right. This opens up the possibility for more children and adults to have access to learning through powered mobility practice. Implications for rehabilitation Tool use learning through powered mobility practice is a therapeutic intervention in its own right. Powered mobility practice can be used as a rehabilitation tool with individuals who may not need to become powered wheelchair users. Motivation, confidence, permissiveness, attentiveness and co-construction are key properties for enabling the application of the learning approach of the ALP tool. Labelling and the use of language, together with honing observational skills through viewing video footage, are key to developing successful learning partnerships.

Complex basin evolution in the Gökova Gulf region: implications on the Late Cenozoic tectonics of southwest Turkey

NASA Astrophysics Data System (ADS)

Gürer, Ömer Feyzi; Sanğu, Ercan; Özburan, Muzaffer; Gürbüz, Alper; Sarica-Filoreau, Nuran

2013-11-01

Southwestern Turkey experienced a transition from crustal shortening to extension during Late Cenozoic, and evidence of this was recorded in four distinct basin types in the Muğla-Gökova Gulf region. During the Oligocene-Early Miocene, the upper slices of the southerly moving Lycian Nappes turned into north-dipping normal faults due to the acceleration of gravity. The Kale-Tavas Basin developed as a piggyback basin along the fault plane on hanging wall blocks of these normal faults. During Middle Miocene, a shift had occurred from local extension to N-S compression/transpression, during which sediments in the Eskihisar-Tınaz Basins were deposited in pull-apart regions of the Menderes Massif cover units, where nappe slices were already eroded. During the Late Miocene-Pliocene, a hiatus occurred from previous compressional/transpressional tectonism along intermountain basins and Yatağan Basin fills were deposited on Menderes Massif, Lycian Nappes, and on top of Oligo-Miocene sediments. Plio-Quaternary marked the activation of N-S extension and the development of the E-W-trending Muğla-Gökova Grabens, co-genetic equivalents of which are common throughout western Anatolia. Thus, the tectonic evolution of the western Anotolia during late Cenozoic was shifting from compressional to extensional with a relaxation period, suggesting a non-uniform evolution.

Purification of barley dimeric α-amylase inhibitor-1 (BDAI-1) and avenin-like protein-a (ALP) from beer and their impact on beer foam stability.

PubMed

Iimure, Takashi; Kihara, Makoto; Sato, Kazuhiro; Ogushi, Kensuke

2015-04-01

Foam stability is a key factor of beer quality for consumers and brewers. Recent beer proteome analyses have suggested that barley dimeric α-amylase inhibitor-1 (BDAI-1) and avenin-like protein-a (ALP) derived from barley are important for beer foam stability. In this study, BDAI-1 and ALP were purified from a Japanese commercial beer sample using salt precipitation and column chromatography. The purification level was verified using two-dimensional gel electrophoresis, mass spectrometry, and database searches. Purified BDAI-1 and ALP were added to a beer sample to compare the foam stability to that of a control beer sample. As a result, beer foam stability was significantly improved by BDAI-1 but not by ALP, thereby suggesting that BDAI-1 affects beer foam stability whereas ALP does not. Copyright © 2014 Elsevier Ltd. All rights reserved.

Use of Sirolimus (Rapamycin) for Treatment of Cytopenias and Lymphoproliferation Linked to Autoimmune Lymphoproliferative Syndrome (ALPS). Two Case Reports.

PubMed

Cayrol, Julie; Garrido Colino, Carmen

2017-05-01

Autoimmune lymphoproliferative syndrome (ALPS) is a disorder of lymphocyte apoptosis. Children present with chronic nonmalignant lymphadenopathy, hepatosplenomegaly, and autoimmune cytopenias. Recent advances show efficacy of treatment with immunosuppressive drugs. Sirolimus, an mammalian target of rapamycin inhibitor, improves autoimmune cytopenias and lymphoproliferation, with a safe profile. We present 2 patients, a 5-year-old girl and 15-year-old boy, diagnosed with ALPS with initial partial response to steroid treatment. Autoimmune cytopenias and lymphoproliferation then became refractory to treatment, with recurrence of symptoms. In both cases, treatment with sirolimus was started, with a rapid response, complete remission of cytopenias, and resolution of lymphoproliferation, with no significant adverse effects. sirolimus is an effective and safe drug for controlling children with cytopenias and lymphoproliferation linked to ALPS.

Siderite deposits in northern Italy: Early Permian to Early Triassic hydrothermalism in the Southern Alps

NASA Astrophysics Data System (ADS)

Martin, Silvana; Toffolo, Luca; Moroni, Marilena; Montorfano, Carlo; Secco, Luciano; Agnini, Claudia; Nimis, Paolo; Tumiati, Simone

2017-07-01

We present a minero-petrographic, geochemical and geochronological study of siderite orebodies from different localities of the Southern Alps (northern Italy). Siderite occurs as veins cutting the Variscan basement and the overlying Lower Permian volcano-sedimentary cover (Collio Fm.), and as both veins and conformable stratabound orebodies in the Upper Permian (Verrucano Lombardo and Bellerophon Fms.) and Lower Triassic (Servino and Werfen Fms.) sedimentary sequences of the Lombardian and the Venetian Alps. All types of deposits show similar major- and rare-earth (REE)-element patterns, suggesting a common iron-mineralizing event. The compositions of coexisting siderite, Fe-rich dolomite and calcite suggest formation from hydrothermal fluids at relatively high temperature conditions (≥ 250 °C). Geochemical modelling, supported by REE analyses and by literature and new δ13C and δ18O isotopic data, suggests that fluids responsible for the formation of siderite in the Variscan basement and in the overlying Lower Permian cover were derived from dominant fresh water, which leached Fe and C from volcanic rocks (mainly rhyolites/rhyodacites) and organic carbon-bearing continental sediments. On the basis of U-Th-Pb microchemical dating of uraninite associated with siderite in the Val Vedello and Novazza deposits (Lombardian Alps), the onset of hydrothermalism is constrained to 275 ± 13 Ma (Early-Mid Permian), i.e., it was virtually contemporaneous to the plutonism and the volcanic-sedimentary cycle reported in the same area (Orobic Basin). The youngest iron-mineralizing event is represented by siderite veins and conformable orebodies hosted in Lower Triassic shallow-marine carbonatic successions. In this case, the siderite-forming fluids contained a seawater component, interacted with the underlying Permian successions and eventually replaced the marine carbonates at temperatures of ≥ 250 °C. The absence of siderite in younger rocks suggests an Early Triassic

Snow covered Alps of France, Italy, and Switzerland

NASA Image and Video Library

1973-07-30

SL3-121-2438 (July-September 1973) --- The Alps of Switzerland, France and Italy are featured in this exceptional photograph taken by a hand-held camera from the Skylab space station during the second manned Skylab mission. Also visible in the out-the-window 70mm Hasselblad view are Lake Geneva, Lake of Lucerne, Rhone River and many other features. The Skylab 3 crewmen, astronauts Alan L. Bean, Owen K. Garriott and Jack R. Lousma completed a 59-day mission with a successful splashdown on Sept. 25, 1973. Photo credit: NASA

Resuscitation Outcomes Consortium-Amiodarone, Lidocaine or Placebo Study (ROC-ALPS): Rationale and methodology behind an out-of-hospital cardiac arrest antiarrhythmic drug trial.

PubMed

Kudenchuk, Peter J; Brown, Siobhan P; Daya, Mohamud; Morrison, Laurie J; Grunau, Brian E; Rea, Tom; Aufderheide, Tom; Powell, Judy; Leroux, Brian; Vaillancourt, Christian; Larsen, Jonathan; Wittwer, Lynn; Colella, M Riccardo; Stephens, Shannon W; Gamber, Mark; Egan, Debra; Dorian, Paul

2014-05-01

Despite their wide use, whether antiarrhythmic drugs improve survival after out-of-hospital cardiac arrest (OHCA) is not known. The ROC-ALPS is evaluating the effectiveness of these drugs for OHCA due to shock-refractory ventricular fibrillation or pulseless ventricular tachycardia (VF/VT). ALPS will randomize 3,000 adults across North America with nontraumatic OHCA, persistent or recurring VF/VT after ≥1 shock, and established vascular access to receive up to 450 mg amiodarone, 180 mg lidocaine, or placebo in the field using a double-blind protocol, along with standard resuscitation measures. The designated target population is all eligible randomized recipients of any dose of ALPS drug whose initial OHCA rhythm was VF/VT. A safety analysis includes all randomized patients regardless of their eligibility, initial arrhythmia, or actual receipt of ALPS drug. The primary outcome of ALPS is survival to hospital discharge; a secondary outcome is functional survival at discharge assessed as a modified Rankin Scale score ≤3. The principal aim of ALPS is to determine if survival is improved by amiodarone compared with placebo; secondary aim is to determine if survival is improved by lidocaine vs placebo and/or by amiodarone vs lidocaine. Prioritizing comparisons in this manner acknowledges where differences in outcome are most expected based on existing knowledge. Each aim also represents a clinically relevant comparison between treatments that is worth investigating. Results from ALPS will provide important information about the choice and value of antiarrhythmic therapies for VF/VT arrest with direct implications for resuscitation guidelines and clinical practice. Copyright © 2014 Mosby, Inc. All rights reserved.

Altitudinal and chiral signature of persistent organochlorine pesticides in air, soil, and spruce needles (Picea abies) of the Alps.

PubMed

Shen, Heqing; Henkelmann, Bernhard; Levy, Walkiria; Zsolnay, Adam; Weiss, Peter; Jakobi, Gert; Kirchner, Manfred; Moche, Wolfgang; Braun, Katharina; Schramm, Karl-Werner

2009-04-01

The present study investigated the distribution, transportation, and biodegradation of the selected chiral persistent organochlorine pesticides (OCP) in the Alps. In the complex environment, we found the movement and fate of OCP could be defined by many factors. Taking HCE as an example, below the timberline its accumulation from air into SPMD increased with altitude and seasonally changed, but the trends reversed above the timberline. In soil, the tendency of HCE concentrations vs organic materials followed a sigmoid curve, and HCE concentration-altitude correlations are positive in central Alps but negative in southern Alps. The HCE enantiomeric ratios (ERs) in soil correlated to HCE isomers concentrations, the humus pH values, and the sampling site altitudes. HCE shift from humus to mineral soil can also be traced by ERs. The altitudinal and longitudinal trends in needles suggested that alpha-HCH has a more complex movementthan HCE in Alps. In conclusion, altitude conducted condensation, plant canopies, organic material in soil, and geographic specific precipitations may affect OCP distributions and transportation, whereas altitude conducted temperature and soil pH could dictate their fate in the environment.

Continent-continent collision in southern Alps studied

NASA Astrophysics Data System (ADS)

Henyey, T.; Stern, T.; Molnar, P.

Developing a scientific plan for geophysical study of the Southern Alps, New Zealand, was the focus of a workshop convened from April 5 to 10 at Victoria University in Wellington, New Zealand. The study is a cooperative effort between U.S. and New Zealand scientists. The workshop was convened by F. Davey, Institute for Geological and Nuclear Sciences, Wellington, New Zealand; T. Stern, Victoria University, Wellington; and T. Henyey and D. Okaya, University of Southern California, Los Angeles. It was sponsored by the National Science Foundation Continental Dynamics Program with assistance from the New Zealand Institute of Geological and Nuclear Sciences and Victoria University.

Lichenized and lichenicolous fungi from the Albanian Alps (Kosovo, Montenegro).

PubMed

Strasser, Eva A; Hafellner, Josef; Stešević, Danijela; Geci, Fehmi; Mayrhofer, Helmut

2015-11-01

396 taxa (381 species) of lichenized and 45 species of lichenicolous fungi from the upper montane, subalpine and alpine belts of the Albanian Alps (= Prokletije Mountain Range, Bjeshkët e Nemuna) are presented. 92 lichenized and 26 lichenicolous fungi are new to Montenegro, 165 lichenized and 24 lichenicolous fungi are new to Kosovo, and 25 lichenized fungi (23 species) are new for the Balkan Peninsula.

Alternations in burial and exhumation along the Selimiye (Kayabükü) shear zone in the Menderes Massif from detailed garnet pressure-temperature paths

NASA Astrophysics Data System (ADS)

Kelly, E. D.; Atakturk, K. R.; Catlos, E. J.; Lizzadro-McPherson, D. J.; Cemen, I.; Lovera, O. M.

2015-12-01

Pressure-temperature (P-T) paths derived from garnet chemical zoning and supported by thermal modeling record alternating burial and exhumation during Main Menderes Metamorphism in western Turkey. We studied six rocks along the Selimiye (Kayabükü) shear zone, three from the footwall (Çine nappe) and three from the hanging wall (Selimiye nappe). The shear zone bounds the southern Menderes Massif metamorphic core complex and has been suggested to record compression followed by extension. The rocks are lower-amphibolite facies garnet-bearing metapelites with nearly identical mineral suites. Retrograde overprinting hinders classical thermobarometry; to overcome this, preserved chemical zoning in garnet combined with a G-minimization approach was used to construct detailed P-T paths (e.g., 50 points in some paths). During continuous temperature increase, the Çine nappe paths show increasing, decreasing, and then increasing pressure (an N-shaped path) ending at 7-8 kbar and ~565-590 °C. The Selimiye nappe paths show a single increase in P-T ending at ~7.3 kbar and ~580 °C. Similar bulk-rock compositions in all samples and the separation by the shear zone suggest that garnets grew during distinct events in each nappe. The timing of garnet growth, and thus the P-T paths, is currently undetermined, as monazite inclusions in garnet appear secondary and complicated by excess common Pb. The Çine nappe N-shaped path describes alternations in burial and exhumation, possibly due to thrust motion along the shear zone. To demonstrate the physical plausibility of the P-T paths, a 2-D finite difference solution to the diffusion-advection equation was applied. The results of the thermal modeling suggest that thrusting, denudation, and renewed thrusting would produce similar changes in P-T to the N-shaped path. Thus, the Çine nappe N-shaped P-T path appears to record a gap in thrust motion along the Selimiye (Kayabükü) shear zone prior to ultimate unroofing of the massif.

Soils evolution and treeline fluctuations under late Holocene climatic changes: an integrated approach from Valle d'Aosta (Western European Alps, Italy)

NASA Astrophysics Data System (ADS)

Masseroli, Anna; Leonelli, Giovanni; Verrecchia, Eric P.; Sebag, David; Pozzi, Emanuele D.; Pelfini, Manuela; Maggi, Valter; Trombino, Luca

2017-04-01

The treeline ecotone, defined as the transition belt in mountain vegetation between the closed forest (timberline) and the alpine grasslands, is one of the most distinctive features of mountain environments and it is widely considered as a climatic boundary. Treeline altitudinal fluctuations may be considered to assess past and ongoing climatic and environmental changes. Although the ecological dynamics of the alpine treeline ecotone is mainly influenced by climate, especially by soil temperature, climatic parameters are not the only factors that influence the treeline position. In fact, the treeline altitude may be locally influenced by environmental factors, geomorphological processes, soil development, and human activities. This study aims at the reconstruction of late Holocene soil evolution and environmental changes at the treeline on the SW slope of the Becca di Viou Mountain in Valle d'Aosta (Western Italian Alps). First, we performed a detailed reconstruction of the treeline altitudinal dynamics. In addition, field (including air and soil temperatures) and laboratory (of both mineral and organic compounds) characterizations have been performed along two transects of seven soil profiles developing at an altitude ranging from 2100 m a.s.l. (closed forest) to 2400 m a.s.l. (treeline ecotone), in order to understand the relationships between colonization by trees and soil development under the ongoing climate change. The upward shift of the treeline was assessed analyzing tree age distribution along the slope by means of a tree-ring based approach. The reconstruction of the treeline altitudinal dynamics (based on years at which the trees reached 2 m in height) at the study site reveals an upward shift of 115 m over the period 1901-2000, reaching the altitude of 2515 m a.s.l. in 2008. The recent treeline shift and the acceleration of tree colonization rates in the alpine belt can be mainly attributed to a climatic input, and particularly to an increasing

The late Barremian Halimedides horizon of the Dolomites (Southern Alps, Italy).

PubMed

Lukeneder, Alexander; Uchman, Alfred; Gaillard, Christian; Olivero, Davide

2012-06-01

A new trace fossil marker level, the Halimedides horizon, is proposed for the Lower Cretaceous pelagic to hemipelagic succession of the Puez area (Southern Alps, Italy). The horizon occurs in the middle part of the late Barremian Gerhardtia sartousiana Zone ( Gerhardtia sartousiana Subzone). It is approximately 20 cm thick and restricted to the uppermost part of the Puez Limestone Member (marly limestones; Hauterivian-Barremian; Puez Formation). It is fixed to the top 20 cm of bed P1/204. The grey-whitish limestone bed of the G. sartousiana Zone is penetrated by Aptian red marls-siltstones of the Redbed Member. The horizon is documented for the first time from the Southern Alps, including the Dolomites, and can be correlated with other Mediterranean localities. The trace fossil assemblage of this marker bed with the co-occurrence of Halimedides , Spongeliomorpha and Zoophycos sheds light on the Lower Cretaceous sedimentological history and current system of the Puez area within the Dolomites. It also highlights the palaeoenvironmental evolution of basins and plateaus and provides insights into the late Barremian interval.

The late Barremian Halimedides horizon of the Dolomites (Southern Alps, Italy)

PubMed Central

Lukeneder, Alexander; Uchman, Alfred; Gaillard, Christian; Olivero, Davide

2012-01-01

A new trace fossil marker level, the Halimedides horizon, is proposed for the Lower Cretaceous pelagic to hemipelagic succession of the Puez area (Southern Alps, Italy). The horizon occurs in the middle part of the late Barremian Gerhardtia sartousiana Zone (Gerhardtia sartousiana Subzone). It is approximately 20 cm thick and restricted to the uppermost part of the Puez Limestone Member (marly limestones; Hauterivian–Barremian; Puez Formation). It is fixed to the top 20 cm of bed P1/204. The grey–whitish limestone bed of the G. sartousiana Zone is penetrated by Aptian red marls–siltstones of the Redbed Member. The horizon is documented for the first time from the Southern Alps, including the Dolomites, and can be correlated with other Mediterranean localities. The trace fossil assemblage of this marker bed with the co-occurrence of Halimedides, Spongeliomorpha and Zoophycos sheds light on the Lower Cretaceous sedimentological history and current system of the Puez area within the Dolomites. It also highlights the palaeoenvironmental evolution of basins and plateaus and provides insights into the late Barremian interval. PMID:27087717

Plate-boundary kinematics in the Alps: Motion in the Arosa suture zone

NASA Astrophysics Data System (ADS)

Ring, Uwe; Ratschbacher, Lothar; Frisch, Wolfgang

1988-08-01

The Arosa zone forms a melange complex along the Penninic/Austroalpine boundary and belongs to the main Alpine suture zone. Accretion and plate collision occurred during Cretaceous and lower Tertiary time. A mixture of ophiolitic rocks and pelagic sediments is imbricated with flysch and blocks of Austroalpine (continental) derivation. We present a description of deformation structures, an analysis of strain, and a kinematic interpretation based on structural work. Deformation histories of imbricates show a translation path that was west-directed between ca. 110 and 50 Ma and north-directed thereafter. The kinematics of the Arosa zone agrees with the recently deduced displacement history of the Austroalpine units in the Eastern Alps during the Cretaceous orogeny. This calls for a predominantly top-to-the-west imbrication of Austroalpine and Penninic units and is in contradiction to what is inferred in most models of the Eastern Alps. A direct relation between the deformation along the Austroalpine margin and relative plate motion existed.

Investigation on AlP as the heterogeneous nucleus of Mg2Si in Al-Mg2Si alloys by experimental observation and first-principles calculation

NASA Astrophysics Data System (ADS)

Sun, Jiayue; Li, Chong; Liu, Xiangfa; Yu, Liming; Li, Huijun; Liu, Yongchang

2018-03-01

The microstructural evolution of primary Mg2Si in Al-20%Mg2Si with Al-3%P master alloy was observed by scanning electron microscope. And the interfacial properties of AlP/Mg2Si interface were investigated using first-principles calculations. The calculation results show that AlP(1 0 0)/Mg2Si(2 1 1) and AlP(3 3 1)/Mg2Si(1 1 0) interfaces can form steadily. P-terminated AlP(1 0 0)/Mg2Si(2 1 1) interface with the largest work of adhesion (4.13 J/m2) is theoretically the most stable. The interfacial electronic structure reveals that there are covalent Si-Al, Si-P and Mg-P bonds existing between AlP and Mg2Si slabs. Due to the AlP particles as effective heterogeneous nucleus of Mg2Si, primary Mg2Si particles change from dendrite to octahedron/truncated octahedron, and their sizes decrease to ∼20 μm.

Strain Localization on Different Scales and their Related Microstructures - Comparison of Microfabrics of Calcite Mylonites from Naxos (Greece) and Helvetic Nappes (Switzerland)

NASA Astrophysics Data System (ADS)

Ebert, A.; Herwegh, M.; Karl, R.; Edwin, G.; Decrouez, D.

2007-12-01

In the upper crust, shear zones are widespread and appear at different scales. Although deformation conditions, shear zone history, and displacements vary in time and space between shear zones and also within them, in all shear zones similar trends in the evolution of large- to micro-scale fabrics can be observed. The microstructural analyses of calcite mylonites from Naxos and various Helvetic nappes show that microstructures from different metamorphic zones vary considerably on the outcrop- and even on the sample- scale. However, grain sizes tend to increase with metamorphic degree in case of Naxos and the Helvetic nappes. Although deformation conditions (e.g. deformation temperature, strain rate, and shear zone geometry, i.e. shear zone width and rock type above/below thrust) vary between the different tectonic settings, microstructural trends (e.g. grain size) correlate with each other. This is in contrast to many previous studies, where no corrections for second phase contents have been applied. In an Arrhenius-type diagram, the grain growth trends of calcite of all studied shear zones fit on a single trend, independent of the dimensions of localized large-scale structures, which is in the dm to m- and km-range in case of the Helvetic thrusts and the marble suite of Naxos, respectively. The calcite grain size increases continuously from few μm to >2mm with a temperature increase from <300°C to >700°C. In a field geologist's point of view, this is an important observation because it shows that natural dynamically stabilized steady state microfabrics can be used to estimate temperature conditions during deformation, although the tectonic settings are different (e.g. strain rate, fluid flow). The reason for this agreement might be related to a scale-dependence of the shear zone dimensions, where the widths increase with increasing metamorphic conditions. In this sense, the deformation volumes affected by localization must closely be linked to the strength of

Ziwundaschg - 10Be dating an Older Dryas cirque glacier moraine in the middle of the Eastern Alps

NASA Astrophysics Data System (ADS)

Moran, Andrew; Ivy-Ochs, Susan; Kerschner, Hanns

2017-04-01

Alpine glacier extents during the Oldest Dryas period (>14.7 ka) are still largely unknown. Moraines from that period are comparatively rare and usually attributed to the "Gschnitz Stadial", which marks the alpine glacier reaction to the first part of Heinrich event 1. In many valleys, in the absence of clear geomorphological evidence, estimates for the glacier extent during that period range between large dendritic valley glacier systems with a well defined, albeit unknown glacier end on the one hand and numerous local valley and cirque glaciers on the other hand. In this context well dated local glacier extents may play an important role, as they provide boundary conditions for the altitude of the equilibrium line (an important palaeoclimatic parameter) and thus limit possible speculations about glacier extents in their vicinity. "Ziwundaschg" is the place name for a cirque in the western Ötztal Mountains near the upper Inn valley and Reschenpass. It is situated more or less in the centre of the Eastern Alps. The cirque floor is at an altitude of about 2000 m and the highest mountains in the back of the cirque are around 2750 m. They were not glacierized during the Little Ice Age, and even a glacierization during the Younger Dryas cold phase was likely limited to a few small ice patches. Further down at the cirque floor, a beautifully developed end moraine with lateral moraines is preserved. 10Be ages from boulders on the moraine cluster around the transition from the Oldest Dryas to the Bølling Interstadial, suggesting moraine stabilization due to the rapid warming at that time. The ELA of the glacier was at about 2200 m a.s.l., roughly 600 - 650 m lower than during the LIA. This value can be taken as representative for the mountain ranges in its vicinity and can form the basis for estimates of glacier extent during the early Lateglacial period in the central Eastern Alps.

Lichenized and lichenicolous fungi from the Albanian Alps (Kosovo, Montenegro)

PubMed Central

Strasser, Eva A.; Hafellner, Josef; Stešević, Danijela; Geci, Fehmi; Mayrhofer, Helmut

2016-01-01

396 taxa (381 species) of lichenized and 45 species of lichenicolous fungi from the upper montane, subalpine and alpine belts of the Albanian Alps (= Prokletije Mountain Range, Bjeshkët e Nemuna) are presented. 92 lichenized and 26 lichenicolous fungi are new to Montenegro, 165 lichenized and 24 lichenicolous fungi are new to Kosovo, and 25 lichenized fungi (23 species) are new for the Balkan Peninsula. PMID:26869727

Palaeoclimate records 60-8 ka in the Austrian and Swiss Alps and their forelands

NASA Astrophysics Data System (ADS)

Heiri, Oliver; Koinig, Karin A.; Spötl, Christoph; Barrett, Sam; Brauer, Achim; Drescher-Schneider, Ruth; Gaar, Dorian; Ivy-Ochs, Susan; Kerschner, Hanns; Luetscher, Marc; Moran, Andrew; Nicolussi, Kurt; Preusser, Frank; Schmidt, Roland; Schoeneich, Philippe; Schwörer, Christoph; Sprafke, Tobias; Terhorst, Birgit; Tinner, Willy

2014-12-01

The European Alps and their forelands provide a range of different archives and climate proxies for developing climate records in the time interval 60-8 thousand years (ka) ago. We review quantitative and semi-quantitative approaches for reconstructing climatic variables in the Austrian and Swiss sector of the Alpine region within this time interval. Available quantitative to semi-quantitative climate records in this region are mainly based on fossil assemblages of biota such as chironomids, cladocerans, coleopterans, diatoms and pollen preserved in lake sediments and peat, the analysis of oxygen isotopes in speleothems and lake sediment records, the reconstruction of past variations in treeline altitude, the reconstruction of past equilibrium line altitude and extent of glaciers based on geomorphological evidence, and the interpretation of past soil formation processes, dust deposition and permafrost as apparent in loess-palaeosol sequences. Palaeoclimate reconstructions in the Alpine region are affected by dating uncertainties increasing with age, the fragmentary nature of most of the available records, which typically only incorporate a fraction of the time interval of interest, and the limited replication of records within and between regions. Furthermore, there have been few attempts to cross-validate different approaches across this time interval to confirm reconstructed patterns of climatic change by several independent lines of evidence. Based on our review we identify a number of developments that would provide major advances for palaeoclimate reconstruction for the period 60-8 ka in the Alps and their forelands. These include (1) the compilation of individual, fragmentary records to longer and continuous reconstructions, (2) replication of climate records and the development of regional reconstructions for different parts of the Alps, (3) the cross-validation of different proxy-types and approaches, and (4) the reconstruction of past variations in climate

Antigenic Determinants of Alpha-Like Proteins of Streptococcus agalactiae

PubMed Central

Maeland, Johan A.; Bevanger, Lars; Lyng, Randi Valsoe

2004-01-01

The majority of group B streptococcus (GBS) isolates express one or more of a family of surface-anchored proteins that vary by strain and that form ladder-like patterns on Western blotting due to large repeat units. These proteins, which are important as GBS serotype markers and as inducers of protective antibodies, include the alpha C (Cα) and R4 proteins and the recently described alpha-like protein 2 (Alp2), encoded by alp2, and Alp3, encoded by alp3. In this study, we examined antigenic determinants possessed by Alp2 and Alp3 by testing of antibodies raised in rabbits, mainly by using enzyme-linked immunosorbent assays (ELISA) and an ELISA absorption test. The results showed that Alp2 and Alp3 shared an antigenic determinant, which may be a unique immunological marker of the Alp variants of GBS proteins. Alp2, in addition, possessed an antigenic determinant which showed specificity for Alp2 and a third determinant which showed serological cross-reactivity with Cα. Alp3, in addition to the determinant common to Alp2 and Alp3, harbored an antigenic site which also was present in the R4 protein, whereas no Alp3-specific antigenic site was detected. These ELISA-based results were confirmed by Western blotting and a fluorescent-antibody test. The results are consistent with highly complex antigenic structures of the alpha-like proteins in a fashion which is in agreement with the recently described structural mosaicism of the alp2 and alp3 genes. The results are expected to influence GBS serotyping, immunoprotection studies, and GBS vaccine developments. PMID:15539502

Several Pleistocene refugia detected in the high alpine plant Phyteuma globulariifolium sternb & hoppe (Campanulaceae) in the European Alps.

PubMed

Schönswetter, P; Tribsch, A; Barfuss, M; Niklfeld, H

2002-12-01

Phyteuma globulariifolium is a high alpine plant species growing in the European Alps and the Pyrenees. In order to elucidate its glacial history, 325 individuals from 69 populations were analysed using the amplified fragment length polymorphism (AFLP) technique. A strongly hierarchical phylogeographical pattern was detected: Two major east-west vicariant groups can be separated along a gap in the distributional area. A further subdivision into at least four populational groups is in congruence with presumed peripheral glacial refugia. There is no indication for survival on unglaciated mountain tops (nunataks) in the interior of the Pleistocene ice shield covering the Alps. Our results favour glacial survival in peripheral, unglaciated or not fully glaciated areas. Populations of P. globulariifolium in the Pyrenees are the result of relatively recent long-distance dispersal. Within the Alps, there is strong differentiation among groups of populations, whereas within them the differentiation is weak. This suggests high levels of gene-flow over short to middle distances.

The Central-Western Mediterranean: Anomalous igneous activity in an anomalous collisional tectonic setting

NASA Astrophysics Data System (ADS)

Lustrino, Michele; Duggen, Svend; Rosenberg, Claudio L.

2011-01-01

The central-western Mediterranean area is a key region for understanding the complex interaction between igneous activity and tectonics. In this review, the specific geochemical character of several 'subduction-related' Cenozoic igneous provinces are described with a view to identifying the processes responsible for the modifications of their sources. Different petrogenetic models are reviewed in the light of competing geological and geodynamic scenarios proposed in the literature. Plutonic rocks occur almost exclusively in the Eocene-Oligocene Periadriatic Province of the Alps while relatively minor plutonic bodies (mostly Miocene in age) crop out in N Morocco, S Spain and N Algeria. Igneous activity is otherwise confined to lava flows and dykes accompanied by relatively greater volumes of pyroclastic (often ignimbritic) products. Overall, the igneous activity spanned a wide temporal range, from middle Eocene (such as the Periadriatic Province) to the present (as in the Neapolitan of southern Italy). The magmatic products are mostly SiO 2-oversaturated, showing calcalkaline to high-K calcalcaline affinity, except in some areas (as in peninsular Italy) where potassic to ultrapotassic compositions prevail. The ultrapotassic magmas (which include leucitites to leucite-phonolites) are dominantly SiO 2-undersaturated, although rare, SiO 2-saturated (i.e., leucite-free lamproites) appear over much of this region, examples being in the Betics (southeast Spain), the northwest Alps, northeast Corsica (France), Tuscany (northwest Italy), southeast Tyrrhenian Sea (Cornacya Seamount) and possibly in the Tell region (northeast Algeria). Excepted for the Alpine case, subduction-related igneous activity is strictly linked to the formation of the Mediterranean Sea. This Sea, at least in its central and western sectors, is made up of several young (< 30 Ma) V-shaped back-arc basins plus several dispersed continental fragments, originally in crustal continuity with the European

Fluid properties control degassing or storage of abiogenic CH4 during slab exhumation: the fluid inclusion record from the Western Alps.

NASA Astrophysics Data System (ADS)

Ferrando, S.; Castelli, D.; Frezzotti, M. L.

2017-12-01

Abiogenic CH4 can be produced by interaction between carbonates and reducing fluids derived from the hydration of ultramafics (e.g., mantle peridotite or HP Ol-serpentinite). This process occurs during slab exhumation because cooling promotes serpentinization of olivine in presence of water (Fo + H2O = Atg + Brc and the linked reactions: Fa + H2O = Fe-Atg + Mag + H2 and Atg + CaCO3 + H2 = Di + Brc + CH4 + H2O) at ca. 500-375°C (P=2.0-0.2 GPa). Experiments in the CH4-H2O-NaCl system indicate that, at these conditions, fluids are immiscible even for very low salinity (ca. 3 wt%) and that the NaCl content in the aqueous part of the fluid increases with temperature whereas the CH4 content in the gaseous part shows an opposite trend (Lamb et al., 2002; Li, 2017).In HP rodingite from the Piemonte ophiolite Zone (W Alps), primary fluid inclusions consisting of a brine (6 wt% CaCl2 + 6 wt% NaCl) with H2 + CH4 ≤ 1 mol % [CH4/(H2+CH4) = 0.37-10] occur in vesuvianite veins that formed at P=0.2 GPa and T=375°C. We interpret them as the aqueous part of an immiscible reducing fluid produced during late Alpine serpentinization of the surrounding ultramafics. Interestingly, CH4-H2 gaseous fluids are never reported in rodingite, whereas early CH4-H2O-H2±graphite and CH4-H2±graphite fluid inclusions, with variable gas-water proportions, trapped in calcite at P≤1.0 GPa and T≤450°C, are recently reported from HP "graphitized" ophicarbonate from the Lanzo peridotite Massif (W Alps; Vitale Brovarone et al., 2017).Both HP ophiolites and partially-serpentinized peridotite massifs are, thus, efficient lithologies to produce CH4 during exhumation. The amount of released CH4 depends on the amount of water available during exhumation. However, when fluids immiscibility occurs, the gaseous-rich part (CH4-H2) of the immiscible fluid produced in ultramafics likely remains confined in the slab because it is less mobile with respect to the aqueous-rich part due to its high dihedral

The interplay between subduction and lateral extrusion: A case study for the European Eastern Alps based on analogue models

NASA Astrophysics Data System (ADS)

van Gelder, I. E.; Willingshofer, E.; Sokoutis, D.; Cloetingh, S. A. P. L.

2017-08-01

A series of analogue experiments simulating intra-continental subduction contemporaneous with lateral extrusion of the upper plate are performed to study the interference between these two processes at crustal levels and in the lithospheric mantle. The models demonstrate that intra-continental subduction and coeval lateral extrusion of the upper plate are compatible processes leading to similar deformation structures within the extruding region as compared to the classical setup, lithosphere-scale indentation. Strong coupling across the subduction boundary allows for the transfer of stresses to the upper plate, where strain regimes are characterized by crustal thickening near a confined margin and dominated by lateral displacement of material near a weak lateral confinement. The strain regimes propagate laterally during ongoing convergence creating an area of overlap characterized by transpression. When subduction is oblique to the convergence direction, the upper plate is less deformed and as a consequence the amount of lateral extrusion decreases. In addition, strain is partitioned along the oblique plate boundary resulting in less subduction in expense of right lateral displacement close to the weak lateral confinement. Both oblique and orthogonal subduction models have a strong resemblance to lateral extrusion tectonics of the Eastern Alps (Europe), where subduction of the adjacent Adriatic plate beneath the Eastern Alps is debated. Our results imply that subduction of Adria is a valid mechanisms to induce extrusion-type deformation within the Eastern Alps lithosphere. Furthermore, our findings suggest that the Oligocene to Late Miocene structural evolution of the Eastern Alps reflects a phase of oblique subduction followed by a later stage of orthogonal subduction conform a Miocene shift in the plate motion of Adria. Oblique subduction also provides a viable mechanism to explain the rapid decrease in slab length of the Adriatic plate beneath the Eastern Alps

The 50 Most Important Questions Relating to the Maintenance and Restoration of an Ecological Continuum in the European Alps

PubMed Central

Walzer, Chris; Kowalczyk, Christine; Alexander, Jake M.; Baur, Bruno; Bogliani, Giuseppe; Brun, Jean-Jacques; Füreder, Leopold; Guth, Marie-Odile; Haller, Ruedi; Holderegger, Rolf; Kohler, Yann; Kueffer, Christoph; Righetti, Antonio; Spaar, Reto; Sutherland, William J.; Ullrich-Schneider, Aurelia; Vanpeene-Bruhier, Sylvie N.; Scheurer, Thomas

2013-01-01

The European Alps harbour a unique and species-rich biodiversity, which is increasingly impacted by habitat fragmentation through land-use changes, urbanization and expanding transport infrastructure. In this study, we identified the 50 most important questions relating to the maintenance and restoration of an ecological continuum – the connectedness of ecological processes across many scales including trophic relationship and disturbance processes and hydro-ecological flows in the European Alps. We initiated and implemented a trans-national priority setting exercise, inviting 48 institutions including researchers, conservation practitioners, NGOs, policymakers and administrators from the Alpine region. The exercise was composed of an initial call for pertinent questions, a first online evaluation of the received questions and a final discussion and selection process during a joint workshop. The participating institutions generated 484 initial questions, which were condensed to the 50 most important questions by 16 workshop participants. We suggest new approaches in tackling the issue of an ecological continuum in the Alps by analysing and classifying the characteristics of the resulting questions in a non-prioritized form as well as in a visual conceptualisation of the inter-dependencies among these questions. This priority setting exercise will support research and funding institutions in channelling their capacities and resources towards questions that need to be urgently addressed in order to facilitate significant progress in biodiversity conservation in the European Alps. PMID:23341928

Total mercury and methylmercury in high altitude surface snow from the French Alps.

PubMed

Marusczak, Nicolas; Larose, Catherine; Dommergue, Aurélien; Yumvihoze, Emmanuel; Lean, David; Nedjai, Rachid; Ferrari, Christophe

2011-09-01

Surface snow samples were collected weekly from the 31st of December 2008 to the 21st of June 2009 from Lake Bramant in the French Alps. Total mercury (THg), total dissolved mercury (THgD), methylmercury (MeHg) and particle distributions in surface snow were analyzed. Results showed that THg concentrations, MeHg concentrations and particle load increased with snow surface temperature, which is an indicator of rising temperatures as the season progresses. Significant correlations between MeHg and snow surface temperature and MeHg and total particles greater than 10 μm were observed. This suggests that the MeHg found in the snow originates from atmospheric deposition processes rather than in situ snowpack sources. This study suggests that an important post-winter atmospheric deposition of MeHg and THg occurs on summital zones of the French Alps and it is likely that this contamination originates from the surrounding valleys. Copyright © 2011 Elsevier B.V. All rights reserved.

Plant-wax D/H ratios in the southern European Alps record multiple aspects of climate variability

NASA Astrophysics Data System (ADS)

Wirth, Stefanie B.; Sessions, Alex L.

2016-09-01

We present a Younger Dryas-Holocene record of the hydrogen isotopic composition of sedimentary plant waxes (δDwax) from the southern European Alps (Lake Ghirla, N-Italy) to investigate its sensitivity to climatic forcing variations in this mid-latitude region (45°N). A modern altitudinal transect of δD values of river water and leaf waxes in the Lake Ghirla catchment is used to test present-day climate sensitivity of δDwax. While we find that altitudinal effects on δDwax are minor at our study site, temperature, precipitation amount, and evapotranspiration all appear to influence δDwax to varying extents. In the lake-sediment record, δDwax values vary between -134 and -180‰ over the past 13 kyr. The long-term Holocene pattern of δDwax parallels the trend of decreasing temperature and is thus likely forced by the decline of northern hemisphere summer insolation. Shorter-term fluctuations, in contrast, may reflect both temperature and moisture-source changes. During the cool Younger Dryas and Little Ice Age (LIA) periods we observe unexpectedly high δDwax values relative to those before and after. We suggest that a change towards a more D-enriched moisture source is required during these intervals. In fact, a shift from northern N-Atlantic to southern N-Atlantic/western Mediterranean Sea sources would be consistent with a southward migration of the Westerlies with climate cooling. Prominent δDwax fluctuations in the early and middle Holocene are negative and potentially associated with temperature declines. In the late Holocene (<4 kyr BP), excursions are partly positive (as for the LIA) suggesting a stronger influence of moisture-source changes on δDwax variation. In addition to isotopic fractionations of the hydrological cycle, changes in vegetation composition, in the length of the growing season, and in snowfall amount provide additional potential sources of variability, although we cannot yet quantitatively assess these in the paleo-record. We

Effect of AlP coating on electrochemical properties of LiMn{sub 2}O{sub 4} cathode material for lithium ion battery

DOE Office of Scientific and Technical Information (OSTI.GOV)

Feng, Xiaoyu; Zhang, Jianxin, E-mail: jianxin@sdu.edu.cn; Yin, Longwei

2016-02-15

Highlights: • Modified LiMn{sub 2}O{sub 4} surface with AlP successfully. • AlP coating surface modification enhances the cycling stability of LiMn{sub 2}O{sub 4} at both room temperature and 60 °C. • AlP coating surface modification improves the rate capability of LiMn{sub 2}O{sub 4}. - Abstract: AlP-modified LiMn{sub 2}O{sub 4} has been synthesized via a simple chemical deposition method followed by high-temperature heating. The X-ray diffraction patterns, SEM images and Energy Dispersive Spectrometer show the successful surface coating of LiMn{sub 2}O{sub 4} by F-43 m crystal form AlP. AlP-modified LiMn{sub 2}O{sub 4} has a high discharge capacity of 125.7 mAh g{supmore » −1} with retention of 87% at a current density of 1C between 3.3 V and 4.3 V after 100 cycles at 60 °C, while bare LiMn{sub 2}O{sub 4} has more than 28% capacity loss. At 10 rates, the coated sample delivers capacity of 100 mAh g{sup −1}, which is much higher than bare LiMn{sub 2}O{sub 4}. Based on the EIS (electrochemical impedance spectroscopy) result, AlP coating can effectively inhibit the increase of the charge transfer resistance during charging and discharging cycles.« less

Carbon dioxide generation and drawdown during active orogenesis of siliciclastic rocks in the Southern Alps, New Zealand

NASA Astrophysics Data System (ADS)

Menzies, Catriona D.; Wright, Sarah L.; Craw, Dave; James, Rachael H.; Alt, Jeffrey C.; Cox, Simon C.; Pitcairn, Iain K.; Teagle, Damon A. H.

2018-01-01

Collisional mountain building influences the global carbon cycle through release of CO2 liberated by metamorphic reactions and promoting mechanical erosion that in turn increases chemical weathering and drawdown of atmospheric CO2. The Southern Alps is a carbonate-poor, siliciclastic mountain belt associated with the active Australian Pacific plate boundary. On-going, rapid tectonic uplift, metamorphism and hydrothermal activity are mobilising carbon. Here we use carbon isotope measurements of hot spring fluids and gases, metamorphic host rocks, and carbonate veins to establish a metamorphic carbon budget. We identify three major sources for CO2 within the Southern Alps: (1) the oxidation of graphite; (2) consumption of calcite by metamorphic reactions at the greenschist-amphibolite facies boundary, and (3) the dissolution of groundmass and vein-hosted calcite. There is only a minor component of mantle CO2 arising on the Alpine Fault. Hot springs have molar HCO3-/Ca2+ ∼9, which is substantially higher than produced by the dissolution of calcite indicating that deeper metamorphic processes must dominate. The total CO2 flux to the near surface environment in the high uplift region of the Southern Alps is estimated to be ∼6.4 × 108 mol/yr. Approximately 87% of this CO2 is sourced from coupled graphite oxidation (25%) and disseminated calcite decarbonation (62%) reactions during prograde metamorphism. Dissolution of calcite and mantle-derived CO2 contribute ∼10% and ∼3% respectively. In carbonate-rich orogens CO2 production is dominated by metamorphic decarbonation of limestones. The CO2 flux to the atmosphere from degassing of hot springs in the Southern Alps is 1.9 to 3.2 × 108 mol/yr, which is 30-50% of the flux to the near surface environment. By contrast, the drawdown of CO2 through surficial chemical weathering ranges between 2.7 and 20 × 109 mol/yr, at least an order of magnitude greater than the CO2 flux to the atmosphere from this orogenic belt

Vegetation changes and timberline fluctuations in the Central Alps as indicators of holocene climatic oscillations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wick, L.; Tinner, W.

Pollen and plant-macrofossil data are presented for two lakes near the timberline in the Italian (Lago Basso, 2250 m) and Swiss Central Alps (Gouille Rion, 2343 m). The reforestation at both sites started at 9700-9500 BP with Pinus cembra, Larix decidua, and Betula. The timberline reached its highest elevation between 8700 and 5000 BP and retreated after 5000 BP, due to a mid-Holocene climatic change and increasing human impact since about 3500 BP (Bronze Age). The expansion of Picea abies at Lago Basso between ca. 7500 and 6200 BP was probably favored by cold phases accompanied by increased oceanicity, whereasmore » in the area of Gouille Rion, where spruce expanded rather late (between 4500 and 3500 BP), human influence equality might have been important. The mass expansion of Alnus viridis between ca. 5000 and 3500 BP probably can be related to both climatic change and human activity at timberline. During the early and middle Holocene a series of timberline fluctuations is recorded as declines in pollen and macrofossil concentrations of the major tree species, and as increases in nonarboreal pollen in the pollen percentage diagram of Gouille Rion. Most of the periods of low timberline can be correlated by radiocarbon dating the climatic changes in the Alps as indicated by glacier advances in combination with palynological records, solifluction, and dendroclimatical data. Lago Basso and Gouille Rion are the only sites in the Alps showing complete palaeobotanical records of cold phases between 10,000 and 2000 BP with very good time control. The altitudinal range of the Holocene treeline fluctuations caused by climate most likely was not more than 100 to 150 m. A possible correlation of a cold period at ca. 7500-6500 BP (Misox oscillation) in the Alps is made with paleoecological data from North American and Scandinavia and a climate signal in the GRIP ice core from central Greenland 8200 yr ago (ca. 7400 yr uncal. BP).« less

Recognition of hyper-extended rifted margin remnants in the internal zone of the Alpine belt: A tribute to Marco Beltrando

NASA Astrophysics Data System (ADS)

Mohn, Geoffroy; Manatschal, Gianreto

2016-04-01

Marco Beltrando was part of the young generation of Alpine geologists who challenged the interpretation of the Western Alps by combining a classical field approach and modern techniques (e.g. 40Ar/39Ar and (U-Th)/He thermochronology). His work provides the foundation to re-interpret some of the classical sections through the Alpine belt and may impact the way of thinking about the nature and structure of internal parts of collisional orogens. This contribution will present the main outcomes of the work of Marco Beltrando and their implications for the understanding of Alpine type orogens. Since his PhD, Marco Beltrando focused most of his work on the study of the internal parts of the Western Alps. He investigated in great details the complex, multiphase structural and metamorphic evolution of the Penninic units in the Western Alps. He concluded that these units went through several cycles of shortening and extension during the Alpine orogeny, with major implications for the Alps but also other orogenic belts. After his PhD, he focused his research on the pre-orogenic evolution of the Alpine belt. He first worked on the Petit St. Bernard area, where he identified relics of the former hyper-extended Tethyan rifted margin. Thanks to his work and his amazing knowledge of the Western Alps, he understood the potential importance of rift-inheritance in controlling the architecture and evolution of the Alpine belt. In parallel to the study of the orogenic evolution, he developed a new methodology to recognize rift-related lithostratigraphic units in highly deformed and metamorphosed parts of the Alps. His innovative work allowed a re-assessment of several areas in the Western Alps and demonstrates the importance of rift inheritance. Recently, he started a new research project on the evolution of the Southern Alps highlighting the importance of heating and cooling cycles resulting from complex successions of rifting events. In spite of his young age, Marco Beltrando was at

Duration of a large Mafic intrusion and heat transfer in the lower crust: A SHRIMP U-Pb zircon Study in the Ivrea-Verbano Zone (Western Alps, Italy)

USGS Publications Warehouse

Peressini, G.; Quick, J.E.; Sinigoi, S.; Hofmann, A.W.; Fanning, M.

2007-01-01

The Ivrea-Verbano Zone in the western Italian Alps contains one of the world's classic examples of ponding of mantle-derived, mafic magma in the deep crust. Within it, a voluminous, composite mafic pluton, the Mafic Complex, intruded lower-crustal, high-grade paragneiss of the Kinzigite Formation during Permian-Carboniferous time, and is now exposed in cross-section as a result of Alpine uplift. The age of the intrusion is still debated because the results of geochronological studies in the last three decades on different rock types and with various dating techniques range from 250 to about 300 Ma. Sensitive high-resolution ion microprobe (SHRIMP) U-Pb zircon age determinations on 12 samples from several locations within the Mafic Complex were performed to better constrain the age of the igneous event. The results indicate a long history of magma emplacement and cooling, which reconciles the spread in previously published ages. The main intrusive phase took place at 288 ?? 4 Ma, causing a perturbation of the deep-crustal geotherm, which relaxed to the Sm-Nd closure temperature in garnet-free mafic rocks after about 15-20 Myr of sub-solidus cooling at c. 270 Ma. These results suggest that large, deep crustal plutons, such as those identified geophysically at depths of 10-20 km within extended continental crust (e.g. Yellowstone, Rio Grande Rift, Basin and Range) may have formed rapidly but induced a prolonged thermal perturbation. In addition, the data indicate that a significant thermal event affected the country rock of the Mafic Complex at about 310 Ma. The occurrence of an upper amphibolite- to granulite-facies thermal event in the Kinzigite Formation prior to the main intrusive phase of the Mafic Complex has been postulated by several workers, and is corroborated by other geochronological investigations. However, it remains uncertain whether this event (1) was part of a prolonged perturbation of the deep-crustal geotherm, which started long before the onset of

Increasing rock-avalanche frequency correlates with increasing seismic moment release in New Zealand's Southern Alps

NASA Astrophysics Data System (ADS)

McSaveney, Mauri; Cox, Simon; Hancox, Graham

2015-04-01

The occurrence rate of large, spontaneous rock avalanches in New Zealand's Southern Alps has increasing over the last 50 years. The rate has been about 20 events per decade for the last 10 years, whereas for the period 1976-1999, it was 4 per decade. Allen et al. 2011 and Allen and Huggel, 2013 link the increase to alpine permafrost decay due to anthropogenic global warming, similar to the increased occurrence rate in the European Alps which is attributed to this cause. We however suggest a different primary cause, linking the increase to tectonic strain, which has been shown to also affect valley-bottom hot springs in the region. The altitudes from which these landslides have fallen are coincident with the region's topographically protruding slopes which favour stress concentration and failure, and many, but not all, failures have been from already highly fractured rock masses, for which an explanation of the fracturing is called for. Also, the earliest documented spontaneous rock avalanche in the Southern Alps occurred in 1873 and fell from a similar altitude on the same face of the same mountain as the most recent event in 2014. Cox et al. (2014) shows that valley-bottom hot springs in the Southern Alps respond to distant strong earthquakes in a manner suggesting weak local ground deformation and increased bedrock permeability. We suggest that the surrounding slopes respond to the same stimuli. We find that the observed occurrence-rate increase has occurred simultaneously with a seismic-moment-release increase in New Zealand, which follows the trend of global seismic moment release. It may also be associated with the accumulating slope deformations since about 1717 AD, when a great earthquake triggered much slope collapse in the region. In support of this link, Barff (1873) which reports the 1873 landslide from Aoraki/Mount Cook, also reports a seemingly associated but unexplained shift of hot springs in the area. The timing of both coincides with a distant

New, rare or remarkable microfungi in the Italian Alps (Carnic Alps)--part I--ascomycotina.

PubMed

Feige, G B; Ale-Agha, N; Jensen, M; Christiaans, B; Kricke, R

2004-01-01

During our observations in the SE part of the Carnic Alps in the year 2003 we were able to collect and identify 35 ascomycetes on trees and dead wood. Among these one can find numerous ascomycetes of different orders e.g. Pyrenomycetes, Loculoascomycetes and Discomycetes. Some species like Botryosphaeria ribis GROSENLUCHER & DUGGAR on Ribes alpinum L., Dothiora pyrenophora (FR.) FR. on Sorbus aucuparia L., Gemmamyces piceae (BORTH.) CASAGO. on Picea excelsa (LAM.) LINK, Glomerella montana (SACC.) v. ARX & E. MULLER on Sesleria caerulea (L.) ARD, Hymenoscyphus immutabilis (Fuck.) Dennis on Alnus incana (L.) Moench, Hysterographium fraxini (PERS. Ex. FR.) de Not. on Fraxinus ornus L., Lachnellula willkommii (Hartig) DENNIS [= Trichascyphella willkommii (Hartig) NANNF.] on Larix decidua MILL.,Leptosphaeria lycopodina (Mont.) SACC. on Lycopodium annotinum L., Mollisia adenostylidis REHM. on Adenostyles glabra (MILL.) DC., Pezicula cinnamomea (DC.)SACC. [ana: Cryptosporiopsis quercina PETRAK] on Quercus robur L., Pyrenopeziza petiolaris (A. & S. Ex FR.) NANNF. on Acer pseudoplatanus L., Tapesia rosae (PERS.) FUCKEL on Rosa canina L., are new for this area. All specimen are deposited in the Herbarium ESS Mycotheca Parva, Collection G.B. Feige/N. Ale-Agha.

Keeping on: How ALP Brings Disaffected Youth Back to School in Liberia

ERIC Educational Resources Information Center

von Hahmann, Gail; Tengbeh, Josephine F. D.

2008-01-01

Moses is entering 7th grade this semester. He is a graduate of the Accelerated Learning Program (ALP), a Liberian government initiative to assist over-age students to complete six grades of primary school in three years. He has all the interests of a typical 15-year old--fixing generators, playing football, earning money to buy a school uniform.…

Deeply subducted continental fragments - Part 1: Fracturing, dissolution-precipitation, and diffusion processes recorded by garnet textures of the central Sesia Zone (western Italian Alps)

NASA Astrophysics Data System (ADS)

Giuntoli, Francesco; Lanari, Pierre; Engi, Martin

2018-02-01

Contiguous continental high-pressure terranes in orogens offer insight into deep recycling and transformation processes that occur in subduction zones. These remain poorly understood, and currently debated ideas need testing. The approach we chose is to investigate, in detail, the record in suitable rock samples that preserve textures and robust mineral assemblages that withstood overprinting during exhumation. We document complex garnet zoning in eclogitic mica schists from the Sesia Zone (western Italian Alps). These retain evidence of two orogenic cycles and provide detailed insight into resorption, growth, and diffusion processes induced by fluid pulses in high-pressure conditions. We analysed local textures and garnet compositional patterns, which turned out remarkably complex. By combining these with thermodynamic modelling, we could unravel and quantify repeated fluid-rock interaction processes. Garnet shows low-Ca porphyroclastic cores that were stable under (Permian) granulite facies conditions. The series of rims that surround these cores provide insight into the subsequent evolution: the first garnet rim that surrounds the pre-Alpine granulite facies core in one sample indicates that pre-Alpine amphibolite facies metamorphism followed the granulite facies event. In all samples documented, cores show lobate edges and preserve inner fractures, which are sealed by high-Ca garnet that reflects high-pressure Alpine conditions. These observations suggest that during early stages of subduction, before hydration of the granulites, brittle failure of garnet occurred, indicating high strain rates that may be due to seismic failure. Several Alpine rims show conspicuous textures indicative of interaction with hydrous fluid: (a) resorption-dominated textures produced lobate edges, at the expense of the outer part of the granulite core; (b) peninsulas and atoll garnet are the result of replacement reactions; and (c) spatially limited resorption and enhanced transport

The andean ophiolitic megastructures on the Buga-Buenaventura transverse (Western Cordillera—Valle Colombia)

NASA Astrophysics Data System (ADS)

Bourgois, Jacques; Calle, Bernardo; Tournon, Jean; Toussaint, Jean-François

1982-02-01

A structural study of the Buga-Buenaventura transverse in the central part of the Western Cordillera of Colombia, has shown the presence of three structural units which, from bottom to top and from west to east, are: the Rio Dagua unit, the Rio Calima unit, and the Loboguerrero window unit. All three units comprise strata between 120 and 80 m.y. old overlying a basement of green rocks showing the characteristics of submarine flows. The Bolivar ultrabasic and basic massif is geographically linked to the Rio Calima unit, in which green rocks predominate, and is separated from it by a tectonic contact. The upper part of the massif, on the other hand, shows high-temperature metamorphic rocks formed during its emplacement. The Rio Dagua unit shows two tectonic phases with isoclinal folding and development of schistosity. The first phase is contemporaneous with low-grade metamorphism equivalent to lower greenschist facies conditions. The Loboguerrero window unit shows a large recumbent fold oriented towards the southeast. Deformation in the Rio Calima unit is weaker and appears to correspond to a higher structural level than in the two other units. As the attitudes of the S1, schistosity in the Rio Dagua unit and of the shear zones located at the green rocks-sediments contact in this same unit are similar to that of the overthrust at the base of the Rio Calima unit, we are led to postulate that the overthrust belongs to the first phase of deformation, as also does the recumbent fold in the Loboguerrero window unit. We are thus led to propose a southeastward direction of emplacement for the nappes in the Western Cordillera of Colombia. In conclusion, the authors extend their observations and propose a new structural interpretation of the "Occidente Colombiano".

21st Century Climate Change in the European Alps

NASA Astrophysics Data System (ADS)

Gobiet, Andreas; Kotlarski, Sven; Stoffel, Markus; Heinrich, Georg; Rajczak, Jan; Beniston, Martin

2014-05-01

The Alps are particularly sensitive to global warming and warmed twice as much as the global average in the recent past. In addition, the Alps and its surroundings are a densly populated areas where society is affected by climate change in many ways, which calls for reliable estimates of future climate change. However, the complex Alpine region poses considerable challenges to climate models, which translate to uncertainties in future climate projections. Against this background, the present study reviews the state-of-knowledge about 21st century climate change in the Alps based on existing literature and additional analyses. It will be demonstrated that considerable and accelerating changes are not only to be expected with regard to temperature, but also precipitation, global radiation, relative humidity, and closely related impacts like floods, droughts, snow cover, and natural hazards will be effected by global warming. Under the A1B emission scenario, about 0.25 °C warming per decade until the mid of the 21st century and accelerated 0.36 °C warming per decade in the second half of the century is expected. Warming will most probably be associated with changes in the seasonality of precipitation, global radiation, and relative humidity. More intense precipitation extremes and flooding potential are particularly expected in the colder part of the year. The conditions of currently record breaking warm or hot winter or summer seasons, respectively, may become normal at the end of the 21st century, and there is indication for droughts to become more severe in the future. Snow cover is expected to drastically decrease below 1500 - 2000 m and natural hazards related to glacier and permafrost retreat are expected to become more frequent. Such changes in climatic variables and related quantities will have considerable impact on ecosystems and society and will challenge their adaptive capabilities. Acknowledgements: This study has been initiated and is partly funded by

Automated Laser Paint Stripping (ALPS) update

NASA Astrophysics Data System (ADS)

Lovoi, Paul

1993-03-01

To date, the DoD has played a major role in funding a number of paint stripping programs. Some technologies have proven less effective than contemplated. Others are still in the validation phase. Paint stripping is one of the hottest issues being addressed by the finishing industry since the Environmental Protection Agency (EPA) has mandated that chemical stripping using methylene chloride/phenolic type strippers be stopped. The DoD and commercial aircraft companies are hard-pressed to find an alternative. Automated laser paint stripping has been identified as a technique for removing coatings from aircraft surfaces. International Technical Associates (InTA) was awarded a Navy contract for an automated laser paint stripping system (ALPS) that will remove paint from metallic and composite substrates. For the program, which will validate laser paint stripping, InTA will design, build, test, and install a system for fighter-sized aircraft at both the Norfolk and North Island (San Diego) Aviation Depots.

Theoretical calculation of coherent Laue-case conversion between x-rays and ALPs for an x-ray light-shining-through-a-wall experiment

NASA Astrophysics Data System (ADS)

Yamaji, T.; Yamazaki, T.; Tamasaku, K.; Namba, T.

2017-12-01

Single crystals have high atomic electric fields as much as 1 011 V /m , which correspond to magnetic fields of ˜103 T . These fields can be utilized to convert x-rays into axionlike particles (ALPs) coherently similar to x-ray diffraction. In this paper, we perform the first theoretical calculation of the Laue-case conversion in crystals based on the Darwin dynamical theory of x-ray diffraction. The calculation shows that the Laue-case conversion has longer interaction length than the Bragg case, and that ALPs in the keV range can be resonantly converted by tuning an incident angle of x-rays. ALPs with mass up to O (10 keV ) can be searched by light-shining-through-a-wall (LSW) experiments at synchrotron x-ray facilities.

Risk assessment of mountain infrastructure destabilization in the French Alps

NASA Astrophysics Data System (ADS)

Duvillard, Pierre-Allain; Ravanel, Ludovic; Deline, Philip

2015-04-01

In the current context of imbalance of geosystems in connection with the rising air temperature for several decades, high mountain environments are especially affected by the shrinkage of glaciers and the permafrost degradation which can trigger slope movements in the rock slopes (rockfall, rock avalanches) or in superficial deposits (slides, rock glacier rupture, thermokarst). These processes generate a risk of direct destabilization for high mountain infrastructure (huts, cable-cars...) in addition to indirect risks for people and infrastructure located on the path of moving rock masses. We here focus on the direct risk of infrastructure destabilization due to permafrost degradation and/or glacier shrinkage in the French Alps. To help preventing these risks, an inventory of all the infrastructure was carried out with a GIS using different data layers among which the Alpine Permafrost Index Map and inventories of the French Alps glaciers in 2006-2009, 1967-1971 and at the end of the Little Ice Age. 1769 infrastructures have been identified in areas likely characterized by permafrost and/or possibly affected by glacier shrinkage. An index of risk of destabilization has been built to identify and to rank infrastructure at risk. This theoretical risk index includes a characterization of hazards and a diagnosis of the vulnerability. The value of hazard is dependent on passive factors (topography, lithology, geomorphological context...) and on so-considered active factors (thermal state of the permafrost, and changing constraints on slopes related to glacier shrinkage). The diagnosis of vulnerability has meanwhile been established by combining the level of potential damage to the exposed elements with their operational and financial values. The combination of hazard and vulnerability determines a degree of risk of infrastructure destabilization (from low to very high). Field work and several inventories of infrastructure damages were used to validate it. The

Kinematics and Seismotectonics of the Montello Thrust Fault (Southeastern Alps, Italy) Revealed by Local GPS and Seismic Networks

NASA Astrophysics Data System (ADS)

Serpelloni, E.; Anderlini, L.; Cavaliere, A.; Danesi, S.; Pondrelli, S.; Salimbeni, S.; Danecek, P.; Massa, M.; Lovati, S.

2014-12-01

The southern Alps fold-and-thrust belt (FTB) in northern Italy is a tectonically active area accommodating large part of the ~N-S Adria-Eurasia plate convergence, that in the southeastern Alps ranges from 1.5 to 2.5 mm/yr, as constrained by a geodetically defined rotation pole. Because of the high seismic hazard of northeastern Italy, the area is well monitored at a regional scale by seismic and GPS networks. However, more localized seismotectonic and kinematic features, at the scale of the fault segments, are not yet resolved, limiting our knowledge about the seismic potential of the different fault segments belonging to the southeastern Alps FTB. Here we present the results obtained from the analysis of data collected during local seismic and geodetic experiments conducted installing denser geophysical networks across the Montello-Bassano-Belluno system, a segment of the FTB that is presently characterized by a lower sismicity rate with respect to the surrounding domains. The Montello anticline, which is the southernmost tectonic features of the southeastern Alps FTB (located ~15 km south of the mountain front), is a nice example of growing anticline associated with a blind thrust fault. However, how the Adria-Alps convergence is partitioned across the FTB and the seismic potential of the Montello thrust (the area has been struck by a Mw~6.5 in 1695 but the causative fault is still largely debated) remained still unresolved. The new, denser, GPS data show that this area is undergoing among the highest geodetic deformation rates of the entire south Alpine chain, with a steep velocity gradient across the Montello anticline. The earthquakes recorded during the experiment, precisely relocated with double difference methods, and the new earthquake focal mechanisms well correlate with available information about sub-surface geological structures and highlight the seismotectonic activity of the Montello thrust fault. We model the GPS velocities using elastic

Analysis of topography and relief as a function of the tectonic - geomorphologic evolution of the Eastern Alps

NASA Astrophysics Data System (ADS)

Bungies, Nadin; Rosenberg, Claudio

2014-05-01

Alpine topography and relief vary regionally (Frisch et al., 1997), even on the scale of tens of kilometers. The causes of these differences are the aim of this work that is based on a geomorphological study of the eastern Alps. Earlier investigations on the topography of the Central Alps (Rosenberg & Garcia, 2013) show, by using 50 km, 75 km, and 100 km swath profiles, that the relief northward of the Insubric Line increases westward, whereas the relief southwards of the Insubric Line decreases eastward. This trend reflects collisional shortening trends recently observed in the Central Alps (Rosenberg & Kissling, 2013). In this work, we analyse the topography of the eastern Alps from the Brenner Area in the west to the Steiermark Area in the east, based on satellite images and digital terrain models, that cover an area of 36 000 km2 in the Austrian and Italian Alps. Based on these data, new GIS-aided datasets containing selected relief factors have been derived. These data are set in relationship to the eastward decrease in collisional shortening to test whether the latter trend has a geomorphic expression. In order to assess such a relationship north-south striking profiles, subparallel to the shortening direction and in addition to an E-W profile are investigated. It can be shown that the total relief of 3100 m (500-3600 m asl.) in the west of the working area is more pronounced than the total relief of 2300 m (700-3000 m asl) in the east of the working area. Furthermore slopes have higher amplitudes in the west when compared to the east. In the west approximately 65% of the slope profile show slopes larger than 50° while in the east approximately 40% of slopes are larger than 50° (based on 30 m topographic data). The evaluation of potential influencing factors will be achieved by conducting spatial and statistical data analysis and interpretation and is complemented by local studies investigating the evolution of relief for selected geologic units. Here

Targeting Alp7/TACC to the spindle pole body is essential for mitotic spindle assembly in fission yeast

PubMed Central

Tang, Ngang Heok; Okada, Naoyuki; Fong, Chii Shyang; Arai, Kunio; Sato, Masamitsu; Toda, Takashi

2014-01-01

The conserved TACC protein family localises to the centrosome (the spindle pole body, SPB in fungi) and mitotic spindles, thereby playing a crucial role in bipolar spindle assembly. However, it remains elusive how TACC proteins are recruited to the centrosome/SPB. Here, using fission yeast Alp7/TACC, we have determined clustered five amino acid residues within the TACC domain required for SPB localisation. Critically, these sequences are essential for the functions of Alp7, including proper spindle formation and mitotic progression. Moreover, we have identified pericentrin-like Pcp1 as a loading factor to the mitotic SPB, although Pcp1 is not a sole platform. PMID:24937146

[Lessons learned from a distribution incident at the Alps-Mediterranean Division of the French Blood Establishment].

PubMed

Legrand, D

2008-11-01

The Alps-Mediterranean division of the French blood establishment (EFS Alpes-Mediterranée) has implemented a risk management program. Within this framework, the labile blood product distribution process was assessed to identify critical steps. Subsequently, safety measures were instituted including computer-assisted decision support, detailed written instructions and control checks at each step. Failure of these measures to prevent an incident underlines the vulnerability of the process to the human factor. Indeed root cause analysis showed that the incident was due to underestimation of the danger by one individual. Elimination of this type of risk will require continuous training, testing and updating of personnel. Identification and reporting of nonconformities will allow personnel at all levels (local, regional, and national) to share lessons and implement appropriate risk mitigation strategies.

Elastic properties and seismic anisotropy of the Seve Nappe Complex - Laboratory core measurements from the International Continental Drilling Project COSC-1 well, Åre, Sweden

NASA Astrophysics Data System (ADS)

Wenning, Q. C.; Almqvist, B. S. G.; Zappone, A. S.

2015-12-01

The COSC-1 scientific borehole was drilled in the summer of 2014 to ~2.5 km depth to study the structure and composition of the Middle Allochthon of the Central Scandinavian Caledonides. It crosscuts the amphibolite-grade lower part of the Seve nappe and intersects a mylonite zone in the lower 800 m of the borehole. We selected six core samples representing the primary lithologies in the COSC-1 borehole for laboratory investigation of elastic properties. The cores consisted of two amphibolites with differing grain sizes, a calc-silicate gneiss, a felsic gneiss, a coarse grained amphibole bearing gneiss, and a garnet bearing mylonitic schist from the basal shear zone. Both P- and S-waves were measured at ultrasonic frequency (1 MHz), and room temperature hydrostatic pressure conditions up to 260 MPa. Measurements were made along three mutually perpendicular directions, one perpendicular to foliation and two parallel to the foliation with one aligned with mineral lineation. Vp and Vs, anisotropy, and elastic properties are reported as an extrapolation of the high-pressure portion of the ultrasonic measurements back to the intersection with the zero pressure axis. The Vp and Vs in the direction perpendicular to foliation ranges from 5.51-6.67 km/s and 3.18-4.13 km/s, respectively. In the direction parallel to foliation the Vp and Vs ranges from 6.31-7.25 km/s and 3.52-4.35 km/s, respectively. Vp anisotropy ranges from 3% in the calc-silicate gneiss to 18% in mylonitic schist. Acoustic impedance estimations at lithostatic pressure conditions at base of the borehole (70 MPa) show that acoustic impedance contrast generating reflection coefficients between the basal shear zone and overlying units are significant enough to cause seismic reflections. Above the mylonite zone/shear zone, the reflectivity within the lower Seve nappe is due to the impedance contrast between the felsic gneiss and the amphibolite. This result fits with 3D seismic reflection imaging in the area of

Prevalence of acute mountain sickness in the Swiss Alps.

PubMed Central

Maggiorini, M; Bühler, B; Walter, M; Oelz, O

1990-01-01

OBJECTIVE--To assess the prevalence of symptoms and signs of acute mountain sickness of the Swiss Alps. DESIGN--A study using an interview and clinical examination in a representative population of mountaineers. Positive symptoms and signs were assigned scores to quantify the severity of acute mountain sickness. SETTING--Four huts in the Swiss Alps at 2850 m, 3050 m, 3650 m, and 4559 m. SUBJECTS--466 Climbers, mostly recreational: 47 at 2850 m, 128 at 3050 m, 82 at 3650, and 209 at 4559 m. RESULTS--In all, 117 of the subjects were entirely free of symptoms and clinical signs of acute mountain sickness; 191 had one or two symptoms and signs; and 158 had more than two. Those with more than two symptoms and signs were defined as suffering from acute mountain sickness. At 4559 m 11 climbers presented with high altitude pulmonary oedema or cerebral oedema, or both. Men and women were equally affected. The prevalence of acute mountain sickness correlated with altitude: it was 9% at 2850 m, 13% at 3050 m, 34% at 3650 m, and 53% at 4559 m. The most frequent symptoms and signs were insomnia, headache, peripheral oedema, and scanty pulmonary rales. Severe headache, vomiting, dizziness, tachypnoea, and pronounced pulmonary rales were associated with other symptoms and signs and therefore characteristic of acute mountain sickness. CONCLUSION--Acute mountain sickness is not an uncommon disease at moderately high altitude--that is, above 2800 m. Severe headache, vomiting, dizziness, tachypnoea, and pronounced pulmonary rales indicate severe acute mountain sickness, and subjects who suffer these should immediately descend to lower altitudes. PMID:2282425

Natural gas seeps in the French Alps: Sources and pathways

NASA Astrophysics Data System (ADS)

Kloppmann, Wolfram; Blessing, Michaela; Proust, Eric; Gal, Frédéric; Bentivegna, Gaetan; Henry, Benoit; Defossez, Pierrick; Catherine, Lerouge; Humez, Pauline; Mayer, Bernhard; Millot, Romain; Gaucher, Eric

2016-04-01

values found by Moss (1992) for West-alpine Oxfordian shales. CO2 contents of <9% could stem from methane oxidation. He isotope ratios are radiogenic with only minor mantle contributions, as it is typical for the Western Alps (Marty et al., 1992). This preliminary investigation reveals that thermogenic natural gas can migrate naturally to the surface in significant flux rates over millenaries without anthropogenic causes, in cases that appropriate leakage pathways exist. This study was co-funded by French ANR and Canadian NSERC. ND_ABSTRACT@ Etiope G., Feyzullayev A., Baciu C. L. (2009) Marine and Petroleum Geology, 26, 333-344. Etiope G., Zwahlen C., Anselmetti F. S., Kipfer R., Schubert C. J. (2010) Geofluids, 10, 476-485. Marty B., Onions R. K., Oxburgh E. R., Martel D., Lombardi S. (1992) Tectonophysics, 206, 71-78. Moss S. (1992) Journal of the Geological Society, 149, 503-515. Augustin of Hippo (St. Augustin) (approx. 426) De Civitate Dei contra paganos, Vol. Liber XXI, chap. VII

Analysis of the ectoenzymes ADA, ALP, ENPP1, and ENPP3, in the contents of ovarian endometriomas as candidate biomarkers of endometriosis.

PubMed

Trapero, Carla; Jover, Lluis; Fernández-Montolí, Maria Eulàlia; García-Tejedor, Amparo; Vidal, August; Gómez de Aranda, Inmaculada; Ponce, Jordi; Matias-Guiu, Xavier; Martín-Satué, Mireia

2018-02-01

The diagnosis of endometriosis, a prevalent chronic disease with a strong inflammatory component, is usually delayed due to the lack of noninvasive diagnostic tests. Purinergic signaling, a key cell pathway, is altered in many inflammatory disorders. The aim of the present work was to evaluate the levels of adenosine deaminase (ADA), alkaline phosphatase (ALP), ecto-nucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1), and ENPP3, elements of purinergic signaling, as biomarker candidates for endometriosis. A case-control comparative study was conducted to determine ADA, ALP, ENPP1 and ENPP3 levels in echo-guided aspirated fluids of endometriomas (case group) and simple ovarian cysts (control group) using the ELISA technique. Adenosine deaminase, ALP, ENPP1, and ENPP3 were present and quantifiable in the contents of endometriomas and simple cysts. There were significant differences in ADA and ENPP1 levels in endometriomas in comparison with simple cysts (2787 U/L and 103.9 ng/mL more in endometriomas, for ADA and ENPP1, respectively). Comparisons of ALP and ENPP3 levels between the two groups did not reveal significant differences. The ectoenzymes ADA and ENPP1 are biomarker candidates for endometriosis. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

8800 years of high-altitude vegetation and climate history at the Rutor Glacier forefield, Italian Alps. Evidence of middle Holocene timberline rise and glacier contraction

NASA Astrophysics Data System (ADS)

Badino, Federica; Ravazzi, Cesare; Vallè, Francesca; Pini, Roberta; Aceti, Amelia; Brunetti, Michele; Champvillair, Elena; Maggi, Valter; Maspero, Francesco; Perego, Renata; Orombelli, Giuseppe

2018-04-01

Sedimentary archives at or near the timberline ecotone in Alpine glaciated areas contain records to study Holocene climate change and the interplay between climate, ecosystems, and humans. We focused on records of timberline and glacier oscillations in the Rutor Glacier forefield (Western Italian Alps) in the last 8800 years. Human activity in this area was negligible for most of the Holocene. We adopted an integrative stratigraphic approach including proxies for glacier advance and timberline estimation, sedimentary events, and reconstructed temperatures. Changes in timberline ecotone correlate to climate until the Middle Ages. Pollen-stratigraphic evidence of a primary plant succession highlights a lag beween local deglaciation and the first reliable 14C age. The radiocarbon chronology points to a prolonged phase of glacier contraction between 8.8 and 3.7 ka cal BP. Even later the glacier remained within its LIA limits. Between 8.4 and 4 ka cal BP MAT-inferred TJuly fluctuated near 12.4 °C, ca. 3.1 °C higher than today. During this period, a Pinus cembra forest belt grew at 2600 m asl with an upper limit of tree groves placed 434 ± 310 m above the current open forest limit. This Holocene phase of thermal maximum ended between 3.98 and 3.51 ± 70 ka cal BP and with a substantial rearrangement of forest composition; temperature reconstruction shows a decrease of 1.8 °C. This climate deterioration concluded the Subboreal thermal optimum, mirroring glacial advances widely documented in the Alps. The Rutor Glacier advanced at ca. AD 1093 ± 65, and remained inside the LIA maximum extent. The LIA started since AD 1594, and culminated between AD 1751 and 1864.

Postcollisional cooling history of the Eastern and Southern Alps and its linkage to Adria indentation

NASA Astrophysics Data System (ADS)

Heberer, Bianca; Reverman, Rebecca Lee; Fellin, Maria Giuditta; Neubauer, Franz; Dunkl, István; Zattin, Massimiliano; Seward, Diane; Genser, Johann; Brack, Peter

2017-07-01

Indentation of rigid blocks into rheologically weak orogens is generally associated with spatiotemporally variable vertical and lateral block extrusion. The European Eastern and Southern Alps are a prime example of microplate indentation, where most of the deformation was accommodated north of the crustal indenter within the Tauern Window. However, outside of this window only the broad late-stage exhumation pattern of the indented units as well as of the indenter itself is known. In this study we refine the exhumational pattern with new (U-Th-Sm)/He and fission-track thermochronology data on apatite from the Karawanken Mountains adjacent to the eastern Periadriatic fault and from the central-eastern Southern Alps. Apatite (U-Th-Sm)/He ages from the Karawanken Mountains range between 12 and 5 Ma and indicate an episode of fault-related exhumation leading to the formation of a positive flower structure and an associated peripheral foreland basin. In the Southern Alps, apatite (U-Th-Sm)/He and fission-track data combined with previous data also indicate a pulse of mainly Late Miocene exhumation, which was maximized along thrust systems, with highly differential amounts of displacement along individual structures. Our data contribute to mounting evidence for widespread Late Miocene tectonic activity, which followed a phase of major exhumation during strain localization in the Tauern Window. We attribute this exhumational phase and more distributed deformation during Adriatic indentation to a major change in boundary conditions operating on the orogen, likely due to a shift from a decoupled to a coupled system, possibly enhanced by a shift in convergence direction.

One microplate - three orogens: Alps, Dinarides, Apennines and the role of the Adriatic plate

NASA Astrophysics Data System (ADS)

Ustaszewski, Kamil; Le Breton, Eline; Balling, Philipp; Handy, Mark R.; Molli, Giancarlo; Tomljenović, Bruno

2017-04-01

The motion of the Adriatic microplate with respect to the Eurasian and African plates is responsible for the Mesozoic to present tectonic evolution of the Alps, Carpathians, the Dinarides and Hellenides as well as the Apennines. The classical approach for reconstructing plate motions is to assume that tectonic plates are rigid, then apply Euler's theorem to describe their rotation on an ideally spherical Earth by stepwise restorations of magnetic anomalies and fracture zones in oceanic basins. However, this approach is inadequate for reconstructing the motion of Mediterranean microplates like Adria, which, at present, is surrounded by convergent margins and whose oceanic portions have by now been entirely subducted. Most constraints on the motion of the Adriatic microplate come either from palaeomagnetics or from shortening estimates in the Alps, i.e., its northern margin. This approach renders plate tectonic reconstructions prone to numerous errors, yielding inadmissible misfits in the Ionian Sea between southern Italy and northern Greece. At the same time, Adria's western and eastern margins in the Apennines and in the Dinarides have hitherto not been appropriately considered for improving constraints on the motion of Adria. This presentation presents new results of ongoing collaborative research that aims at improving the relative motion path for the Adriatic microplate for the Cenozoic by additionally quantifying and restoring the amount of shortening and extension in a set of geophysical-geological transects from the Tyrrhenian Sea, the Apennines and the Dinarides. Already now, our approach yields an improved motion path for the Adriatic microplate for the last 20 Ma, which minimizes misfits in previous reconstructions. The currently largest challenge in our reconstructions is to reconcile amount and age of shortening in the Dinarides fold-and-thrust belt. For one thing, we see good agreement between the cross-sectional length of subducted material (c. 135 km

The Geomorphological Evolution of a Landscape in a Tectonically Active Region: the Sennwald Landslide

NASA Astrophysics Data System (ADS)

Aksay, Selçuk; Ivy-Ochs, Susan; Hippe, Kristina; Graemiger, Lorenz; Vockenhuber, Christof

2016-04-01

The Säntis nappe is a fold-and-thrust structure in eastern Switzerland consisting of numerous tectonic discontinuities that make rocks vulnerable to rock failure. The Sennwald landslide is one of those events that occurred due to the failure of Lower Cretaceous Helvetic limestones. This study reveals the surface exposure age of the event in relation to geological and tectonic setting, earthquake frequency of the Central Alps, and regional scale climate/weather influence. Our study comprises detailed mapping of landform features, thin section analysis of landslide boulder lithologies, landslide volume estimation, numerical DAN-3D run-out modelling, and the spatial and temporal relationship of the event. In the Sennwald landslide, 92 million m3 of limestones detached from the south-eastern wall of the Säntis nappe and slid with a maximum travel distance of ~4'500 m and a "fahrboeschung" angle of 15° along the SE-dipping sliding plane almost parallel to the orientation of the bedding plane. Numerical run-out modelling results match the extent and the thickness of landslide deposits as observed in the field. The original bedrock stratigraphy was preserved as geologically the top layer in the bedrock package travelled the farthest and the bottom layer came to rest closest to the release bedrock wall during the landslide. Velocities of maximum 90 m/s were obtained from the numerical run-out modelling. Total Cl and 36Cl were determined at ETH AMS facility with isotope dilution methods defined in the literature (Ivy-Ochs et al., 2004). Surface exposure ages of landslide deposits in the accumulation area are revealed from twelve boulders. The distribution of limestone boulders in the accumulation area, the exposure ages, and the numerical run-out modelling support the hypothesis that the Sennwald landslide was a single catastrophic event. The event is likely to have been triggered by at least light to moderate earthquakes (Mw=4.0-6.0). The historical and the last 40-year

Spatial distribution and temporal development of high-mountain lakes in western Austria

NASA Astrophysics Data System (ADS)

Merkl, Sarah; Emmer, Adam; Mergili, Martin

2015-04-01

Glacierized high-mountain environments are characterized by active morphodynamics, favouring the rapid appearance and disappearance of lakes. On the one hand, such lakes indicate high-mountain environmental changes such as the retreat of glaciers. On the other hand, they are sometimes susceptible to sudden drainage, leading to glacial lake outburst floods (GLOFs) putting the downstream population at risk. Whilst high-mountain lakes have been intensively studied in the Himalayas, the Pamir, the Andes or the Western Alps, this is not the case for the Eastern Alps. A particular research gap, which is attacked with the present work, concerns the western part of Austria. We consider a study area of approx. 6,140 km², covering the central Alps over most of the province of Tyrol and part of the province of Salzburg. All lakes ≥250 m² located higher than 2000 m asl are mapped from high-resolution Google Earth imagery and orthophotos. The lakes are organized into seven classes: (i) ice-dammed; near-glacial (ii) moraine-dammed and (iii) bedrock-dammed; (iv) moraine-dammed and (v) bedrock-dammed distant to the recent glaciers; (vi) landslide-dammed; (vii) anthropogenic. The temporal development of selected lakes is investigated in detail, using aerial photographs dating back to the 1950s. 1045 lakes are identified in the study area. Only eight lakes are ice-dammed (i). One third of all lakes is located in the immediate vicinity of recent glacier tongues, half of them impounded by moraine (ii), half of them by bedrock (iii). Two thirds of all lakes are impounded by features (either moraines or bedrock) shaped by LIA or Pleistocenic glaciers at some distance to the present glacier tongues (iv and v). Only one landslide-dammed lake (vi) is identified in the study area, whilst 21 lakes are of anthropogenic origin (vii). 72% of all lakes are found at 2250-2750 m asl whilst less than 2% are found above 3000 m asl. The ratio of rock-dammed lakes increases with increasing

Mammoths inside the Alps during the last glacial period: Radiocarbon constraints from Austria and palaeoenvironmental implications

NASA Astrophysics Data System (ADS)

Spötl, Christoph; Reimer, Paula J.; Göhlich, Ursula B.

2018-06-01

This study examines remains of the woolly mammoth (Mammuthus primigenius) found inside the Austrian Alps, an area occupied by an extensive ice-stream network during the Last Glacial Maximum. The data demonstrate that these cold steppe-adapted animals locally migrated several tens of kilometers into alpine valleys. Radiocarbon analyses constrain the age of these fossils to the first half of Marine Isotope Stage 3, documenting ice-free conditions in major valleys at that time. We also provide a list of all traceable Austrian sites of Mammuthus primigenius, totaling about 230 localities, compiled through 15 museums and collections in Austria. The vast majority of these findings are from the corridors of the Danube and Mur rivers and their tributaries and the adjacent loess-covered foreland of the Alps, areas that were never ice-covered during Pleistocene glaciations.

A new interpretation for the interference zone between the southern Brasília belt and the central Ribeira belt, SE Brazil

NASA Astrophysics Data System (ADS)

Trouw, Rudolph A. J.; Peternel, Rodrigo; Ribeiro, Andre; Heilbron, Mônica; Vinagre, Rodrigo; Duffles, Patrícia; Trouw, Camilo C.; Fontainha, Marcos; Kussama, Hugo H.

2013-12-01

In southeastern Brazil, the Neoproterozoic NNW-SSE trending southern Brasília belt is apparently truncated by the ENE-WSW central Ribeira belt. Different interpretations in the literature of the transition between these two belts motivated detailed mapping and additional age dating along the contact zone. The result is a new interpretation presented in this paper. The southern Brasília belt resulted from E-W collision between the active margin of the Paranapanema paleocontinent, on the western side, now forming the Socorro-Guaxupé Nappe, with the passive margin of the São Francisco paleocontinent on the eastern side. The collision produced an east vergent nappe stack, the Andrelândia Nappe System, along the suture. At its southern extreme the Brasília belt was thought to be cut off by a shear zone, the "Rio Jaguari mylonites", at the contact with the Embu terrane, pertaining to the Central Ribeira belt. Our detailed mapping revealed that the transition between the Socorro-Guaxupé Nappe (Brasília belt) and the Embu terrane (Ribeira belt) is not a fault but rather a gradational transition that does not strictly coincide with the Rio Jaguari mylonites. A typical Cordilleran type magmatic arc batholith of the Socorro-Guaxupé Nappe with an age of ca. 640 Ma intrudes biotite schists of the Embu terrane and the age of zircon grains from three samples of metasedimentary rocks, one to the south, one to the north and one along the mylonite zone, show a similar pattern of derivation from a Rhyacian source area with rims of 670-600 Ma interpreted as metamorphic overgrowth. We dated by LA-MC-ICPMS laser ablation (U-Pb) zircon grains from a calc-alkaline granite, the Serra do Quebra-Cangalha Batholith, located within the Embu terrane at a distance of about 40 km south of the contact with the Socorro Nappe, yielding an age of 680 ± 13 Ma. This age indicates that the Embu terrane was part of the upper plate (Socorro-Guaxupé Nappe) by this time. Detailed mapping

Prevalence of cardiovascular diseases among alpine skiers and hikers in the Austrian Alps.

PubMed

Faulhaber, Martin; Flatz, Markus; Gatterer, Hannes; Schobersberger, Wolfgang; Burtscher, Martin

2007-01-01

Mountain sports, especially hiking and alpine skiing, are very popular. It is speculated that a high percentage of hikers and skiers are older and have cardiovascular diseases, but little is known about the real frequency of cardiovascular diseases in mountaineers and skiers. The goal of this study was to provide data on the prevalence of cardiovascular diseases (coronary artery disease with and without myocardial infarction, hypertension, and arrhythmias) of a representative sample of hikers and skiers in the Austrian Alps. Questionnaire results of 1431 hikers and 1043 skiers were included in the evaluation. Regarding the whole sample, 12.7% (11.0 to 14.4) of the hikers and 11.2% (9.3 to 13.1) of the skiers are afflicted with at least one type of cardiovascular disease. The frequency of cardiovascular diseases is age dependent and more pronounced in men, but only small differences were detected between hikers and skiers. It can be assumed that 4 to 5 million hikers and skiers with known cardiovascular diseases are active in the Alps annually. Scientific research should provide the basis of an optimal risk management for this large group of persons.

Deciphering tectonic, climatic-induced and hydrothermal signals in the late-stage exhumation history of the upper Rhône valley (Swiss Alps)

NASA Astrophysics Data System (ADS)

Valla, Pierre; Rahn, Meinert; Shuster, David; van der Beek, Peter

2015-04-01

Neogene exhumation of the European Alps is understood as the interplay between tectonics and climatic-induced erosion. While the former has been influenced by a decrease in plate convergence, the latter has been suggested to be affected by climatic variation and the onset of Plio-Quaternary glaciations, leading to relief amplification. However, even though geomorphologic and sedimentologic studies both suggest topographic relief change and transition from fluvial to oscillations between glacial/fluvial conditions, precise quantification on both the timing and magnitude of this transition are yet sparse. Our study focuses on the upper Rhône valley (Swiss Central Alps) within the Visp-Brig area (Aar massif). This area encompasses some of the most spectacular reliefs within the Alps with several nearby summits around or above 4000 m crosscut by the glacially overdeepened Rhône valley. It also shows among the highest late Neogene exhumation rates within the Western-Central European Alps, influenced by tectonic activity along the major Simplon-Rhône extensional fault system. Moreover, the upper Rhône valley has experienced enhanced glacial erosion associated with strong relief development during the Pliocene-Quaternary period. Finally, structural inheritance, late-stage tectonics and rapid exhumation may have promoted recent hydrothermal activity in this region, although timing of its onset and its precise causes remain poorly understood. We investigated the late-stage cooling history by using different low-temperature thermochronometers along a pseudo-vertical bedrock profile (elevation between 600 and 2900 m) and additional samples from an on-site 500-m geothermal well, resulting in a total elevation difference of nearly 3 km. Apatite fission-track (AFT) ages and track-length data have been added to previously published and new apatite (U-Th-Sm)/He (AHe) and 4He/3He data. Our results confirm high-exhumation rates (0.6 to 0.9 km/Myr) within late-Cenozoic to

Interseismic coupling, seismic potential and earthquake recurrence on the southern front of the Eastern Alps (NE Italy)

NASA Astrophysics Data System (ADS)

Cheloni, Daniele; D'Agostino, Nicola; Selvaggi, Giulio

2014-05-01

The interaction of the African, Arabian, and Eurasia plates in the "greater" Mediterranean region yields to a broad range of tectonic processes including active subduction, continental collision, major continental strike-slip faults and "intra-plate" mountain building. In this puzzling region the convergence between Adria microplate and Eurasia plate is partly or entirely absorbed within the South-Eastern Alps, where the Adriatic lithosphere underthrusts beneath the mountain belt. Historical seismicity and instrumentally recorded earthquakes show thrust faulting on north-dipping low-angle faults in agreement with geological observations of active mountain building and active fold growing at the foothills of the South-Eastern Alps. In this study, we use continuous GPS observations to document the geodetic strain accumulation across the South-Eastern Alps (NE Italy). We estimate the pattern of interseismic coupling on the intra-continental collision north-dipping thrust faults that separate the Eastern Alps and the Venetian-Friulian plain using the back-slip approach and discuss the seismic potential and earthquake recurrence. Comparison between the rigid-rotation predicted motion and the shortening observed across the studied area indicates that the South-Eastern Alpine thrust front absorbs about 80% of the total convergence rate between the Adria microplate and Eurasia plate. The modelled thrust fault is currently locked from the surface to a depth of approximately 10 km. The transition zone between locked and creeping portions of the fault roughly corresponds with the belt of microseismicity parallel and to the north of the mountain front. The estimated moment deficit rate is 1.27±0.14×10^17 Nm/yr. The comparison between the estimated moment deficit and that released historically by the earthquakes suggests that to account for the moment deficit the following two factors or their combination should be considered: (1) a significant part of the observed

New insights into typical Archaean structures in greenstone terranes of western Ontario

NASA Technical Reports Server (NTRS)

Schwerdtner, W. M.

1986-01-01

Ongoing detailed field work in selected granitoid complexes of the western Wabigoon and Wawa Subprovinces, southern Canadian Shield, has led to several new conclusions: (1) Prominent gneiss domes are composed of prestrained tonalite-granodiorite and represent dense hoods of magmatic granitoid diapirs; (2) the deformation history of the prestrained gneiss remains to be unraveled; (3) the gneiss lacked a thick cover of mafic metavolcanics or other dense rocks at the time of magmatic diaprisim; (4) the synclinoral structure of large greenstone belts is older than the late gneiss domes and may have been initiated by volcano-tectonic processes; (5) small greenstone masses within the gneiss are complexly deformed, together with the gneiss; and, (6) no compelling evidence has been found of ductile early thrusting in the gneiss terranes. Zones of greenstone enclaves occur in hornblende-rich contaminated tonalite and are apt to be deformed magmatic septa. Elsewhere, the tonalite gneiss is biotite-rich and hornblende-poor. These conclusions rest on several new pieces of structural evidence; (1) oval plutons of syenite-diorite have magmatic strain fabrics and sharp contacts that are parallel to an axial-plane foliation in the surrounding refolded gneiss; (2) gneiss domes are lithologically composite and contain large sheath-like structures which are deformed early plutons, distorted earlier gneiss domes, or early ductile nappes produced by folding of planar plutonic septa, and (3) the predomal attitudes of gneissosity varied from point to point.

Badgastein spa—Austrian central Alps

NASA Astrophysics Data System (ADS)

Zötl, J. G.

1995-12-01

The Badgastein spa shows almost all the special geological and hydrological features existing in the northeastern central Alps. Situated within the Tauern window, the open joint system enables the infiltration of surface water to great depths. There it becomes heated and loaded with radon and trace elements such as fluor. The water discharges as thermal water springs at the steep right flank of the cascade of the Gastein-Ache. This hydraulic process occurs during a span of 3600 3800 years. The springs are captured in galleries, and the largest discharge is in gallery IX (2518 m3/d-1). The spa became known worldwide in the 19th century by visiting aristocrats from Central and Eastern Europe. The most important event in the 20th century was the discovery of the heat joint in the Böckstein gallery. In 1940 an effort to reactivate gold mining in the Radhausberg near Böckstein south of Badgastein failed. However, the miners had the unexpected experience of being cured of rheumatism. A connection between the great depth and high temperature in the gallery was made by the discovery of the joint set with heat and radon emanation. In the medical stations of the Böckstein gallery treatment of polyarthritis has become especially successful.

Preliminary comparative study of middle Anisian vertebrate ichnoassociation from South-Eastern Alps

NASA Astrophysics Data System (ADS)

Valdiserri, D.; Todesco, R.; Avanzini, M.

2009-04-01

Anisian vertebrate tracks from the south-eastern Alps are known since the first decades of 1900s (Abel, 1926). The sedimentary units yielding footprints are characterized by the alternation of limestone influenced by terrigenous supply with mere marine and volcanic layers allowing a precise dating. In this study, we compare four different ichnoassociations from three different outcrops in the South-Eastern Alps correlating them chronologically and sedimentologically. They were found to be subsequent in time from Lower Pelsonian (Bad Gfrill-Voltago Conglomerate; Todesco, 2007) through middle Pelsonian (Bad Gfrill- Giovo Formation) (Valdiserri et al., 2006) and basal Illyrian (Piz da Peres- Richthofen Conglomerate; Todesco et al., 2008) to the middle Illyrian (Val Duron-Morbiac Limestone; Avanzini et al., 2007). In all these ichno-associations, Rhynchosauroides, an ichno-genus referable to a lizard - like trackmaker well known in the European Anisian, is dominant. Within this group at least four different morphotypes are known, probably reflecting both intraspecific variation (i.e. sexual dimorphism) and different ichnospecies. Although the Chirotheridae group, referred to Archosaurian trackmakers Synaptichnium is represented in both Pelsonian ichnoassociation of the Bad Gfrill outcrop, while Chirotherium , Isochirotherium and Brachichirotherium are recognized both in Pelsonian and in Illyrian ichnosites with a incremental presence in the Illyrian The ichofamiliae Rotodactylidae und Procolophonidae seem well represented in the Pelsonian strata but absent in the Illyrian ones. The preliminarly comparative analysis of these four correlated ichnosites and the comparision with the yet known ones (Avanzini and Mietto 2008) pointed out the expected predominance of the Lepidosaurian-Archosaurian association typical for the middle Triassic ichnofauna. The incremental presence of the Chirotherian track in Illyrian and the presence of the Procolophonichium just in the

Terricolous Lichens in the Glacier Forefield of the Pasterze (Eastern Alps, Carinthia, Austria)

PubMed Central

Bilovitz, Peter O.; Wallner, Anja; Tutzer, Veronika; Nascimbene, Juri; Mayrhofer, Helmut

2016-01-01

Summary The investigation of lichens on soil, plant debris and terricolous mosses in the glacier forefield of the Pasterze yielded 35 lichen species. Placidiopsis oreades Breuss (Verrucariales) is new to Austria. Three sampling sites were established at increasing distance from the glacier, in order to compare species diversity, abundance and composition within the forefield and with four other glacier forefields of the Eastern Alps. PMID:26877565

External micro-PIXE analysis of fluid inclusions: Test of the LABEC facility on samples of quartz veins from Apuan Alps (Italy)

NASA Astrophysics Data System (ADS)

Massi, M.; Calusi, S.; Giuntini, L.; Ruggieri, G.; Dini, A.

2008-05-01

Fluid inclusions are small portions, usually smaller than 100 μm, of fluid trapped within minerals during or after growth. Their characteristics provide therefore fundamental information on nature and evolution of fluids present in the past in different geological environments. At the LABEC laboratory in Firenze, high-salinity fluid inclusions in quartz crystals, coming from the Apuan Alps metamorphic complex, were analysed at the external scanning microbeam. Results, although still preliminary, have already provided us with hints on fluid-rock interaction processes during the metamorphism of the Apuan Alps.

Wind Powering America Anemometer Loan Program: A Retrospective

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jimenez, T.

This white paper details the history, mechanics, status, and impact of the Native American Anemometer Loan Program (ALP) conducted by the U.S. Department of Energy's Wind Powering America (WPA) initiative. Originally conceived in 2000 and terminated (as a WPA activity) at the end of FY 2011, the ALP has resulted in the installation of anemometers at 90 locations. In addition, the ALP provided support for the installation of anemometers at 38 additional locations under a related ALP administered by the Western Area Power Administration.

Phosphorus translocation by red deer on a subalpine grassland in the central European Alps

Treesearch

Martin Schutz; Anita C. Risch; Gerald Achermann; Conny Thiel-Egenter; Deborah Page-Dumroese; Martin F. Jurgensen; Peter J. Edward

2006-01-01

We examined the role of red deer (Cervus elaphus L.) in translocating phosphorus (P) from their preferred grazing sites (short-grass vegetation on subalpine grasslands) to their wider home range in a subalpine grassland ecosystem in the Central European Alps. Phosphorus was used because it is the limiting nutrient in these grasslands. When we compared P removal of...

Kinematics, seismotectonics and seismic potential of the eastern sector of the European Alps from GPS and seismic deformation data

NASA Astrophysics Data System (ADS)

Serpelloni, E.; Vannucci, G.; Anderlini, L.; Bennett, R. A.

2016-10-01

We present a first synoptic view of the seismotectonics and kinematics of the eastern sector of the European Alps using geodetic and seismological data. The study area marks the boundary between the Adriatic and the Eurasian plates, through a wide zone of deformation including a variety of tectonic styles within a complex network of crustal and lithospheric faults. A new dense GPS velocity field, new focal mechanisms and seismic catalogues, with uniformly re-calibrated magnitudes (from 1005), are used to estimate geodetic and seismic deformation rates and to develop interseismic kinematic and fault locking models. Kinematic indicators from seismological and geodetic data are remarkably consistent at different spatial scales. In addition to large-scale surface motion, GPS velocities highlight more localized deformation features revealing a complex configuration of interacting tectonic blocks, for which new constraints are provided in this work accounting for elastic strain build up at faults bonding rotating blocks. The geodetic and seismological data highlight two belts of higher deformation rates running WSW-ENE along the Eastern Southern Alps (ESA) in Italy and E-W in Slovenia, where deformation is more distributed. The highest geodetic strain-rates are observed in the Montello-Cansiglio segment of the ESA thrust front, for which the higher density of the GPS network provides indications of limited interseismic locking. Most of the dextral shear between the Eastern Southern Alps and the Eastern Alps blocks is accommodated along the Fella-Sava fault rather than the Periadriatic fault. In northern Croatia and Slovenia geodetic and seismological data allow constraining the kinematics of the active structures bounding the triangular-shaped region encompassing the Sava folds, which plays a major role in accommodating the transition from Adria- to Pannonian-like motion trends. The analysis of the seismic and geodetic moment rates provides new insights into the seismic

Interannual variability of rock glacier surface velocities and its relationship to climatic conditions on a decadal scale: Some insights from the European Alps

NASA Astrophysics Data System (ADS)

Kellerer-Pirklbauer, Andreas; Bodin, Xavier; Delaloye, Reynald; Fischer, Andrea; Gärtner-Roer, Isabelle; Hartl, Lea; Kaufmann, Viktor; Krainer, Karl; Lambiel, Christophe; Mair, Volkmar; Marcer, Marco; Morra di Cella, Umberto; Scapozza, Cristian; Schoeneich, Philippe; Staub, Benno

2017-04-01

Active, inactive and relict rock glaciers are widespread periglacial landforms in the European Alps as revealed by several inventories elaborated for Slovenia, Austria, Switzerland, Italy, and France. Rock glaciers indicate present or past permafrost conditions in mountain environments and hence have a high climatic or paleoclimatic relevance. The monitoring of surface velocities at active rock glaciers has a long tradition in the European Alps with first terrestrial photogrammetric surveys in the Swiss and Austrian Alps already in the 1920s. Since the 1990s velocity monitoring activities have been substantially expanded but also institutionalized. Today, several research groups carry out annual or even continuous monitoring of rock glacier creep at more than 30 rock glaciers in Austria, France, Italy, and Switzerland. In many cases such a kinematic monitoring is jointly accomplished with meteorological and ground temperature monitoring in order to better understand the rock glacier-climate relationships and the reaction of rock glacier behavior to climatic changes. In this contribution we present a synthesis of the main results from long-term monitoring of several rock glaciers in the European Alps with at least annually-repeated data. Similarities but also differences of the movement patterns at the different sites are discussed, while the spatio-temporal pattern of the surface displacement is looked at against the climate context. In general, rock glacier surface velocities in the European Alps have been rather low during the 1980s and 1990s and reached a first peak in 2003/04 followed by a drastic drop until c.2007/08. Since then rock glacier surface velocities increased again with new velocity records in 2015/16 superior to the first peak around 2003/04. These creep rate maxima coincide with the warmest permafrost temperatures ever measured in boreholes and are likely a result of the continuously warm conditions at the ground surface over the past seven years.

Fragments of deeper parts of the hanging wall mantle preserved as orogenic peridotites in the central belt of the Seve Nappe Complex, Sweden

NASA Astrophysics Data System (ADS)

Clos, Frediano; Gilio, Mattia; van Roermund, Herman L. M.

2014-04-01

Formation conditions of olivine microstructures are investigated in the Kittelfjäll spinel peridotite (KSP), a fragment of lithospheric mantle which occurs as an isolated body within high grade metamorphic crustal rocks of the Seve Nappe Complex (SNC), southern Västerbotten, central Sweden. The KSP is an orogenic peridotite containing a well developed penetrative compositional layering, defined by highly depleted dunite with olivine Mg# (100 × Mg/Mg + Fe) of 92.0-93.5 and harzburgite with lower Mg# (91.0-92.5). Dunite is characterized by three contrasting olivine microstructures formed in response to different tectonometamorphic events: Coarse-grained, highly strained olivine porphyroclasts (M1) up to 20 cm long are surrounded by dynamically recrystallized olivine grains (M2) defining a characteristic olivine "foam" microstructure (grain size: 200-2000 μm). An olivine "mortar" (M3) microstructure (10-50 μm) forms a penetrative fabric element only in strongly localized, cm-to-m sized shear zones that crosscut earlier structures/foliations. Olivine fabric analysis in synergy, with mineralogical and chemical analyses, reveals that the KSP body represents old, possibly Archean, sub-continental lithospheric mantle that was crustally emplaced into the Caledonian tectonic edifice from the hanging wall mantle during exhumation of the subducted Seve Nappe Complex (Jämtlandian orogeny ~ 454 Ma). Olivine porphyroclasts (M1) grew at high temperature during dominant isobaric cooling after extensive polybaric melt extraction (> 40%) and subsequent refertilization. The onset of the early Caledonian deformation is interpreted to be related to the crustal emplacement of the KSP during eduction of the SNC. This phase is characterized by the development of the olivine M2 foam microstructure, formed at 650-830 °C/1-2 GPa by dislocation creep processes producing an E-type CPO's by the operation of the [100](001) and subordinate [001](100) slip systems with operating flow stress

Constraints on the deep structure and dynamic processes beneath the Alps and adjacent regions from an analysis of gravity anomalies

NASA Technical Reports Server (NTRS)

Lyon-Caen, Helene; Molnar, Peter

1989-01-01

Gravity anomalies over the Alps and the Molasse Basin are examined, focusing on the relationship between the anomalies and the tectonic processes beneath the region. Bouguer gravity anomalies measured in France, Germany, Italy, and Switzerland are analyzed. No large isostatic anomalies are observed over the Alps and an elastic model is unable to account for gravity anomalies over the Molasse Basin. These results suggest that the dynamic processes that flexed the European plate down, forming the Molasse Basin and building the Alpine chain, have waned. It is proposed that the late Cenozoic uplift of the region may be due to a diminution or termination of downwelling of mantle material.

Coupled effects of impact and orogeny: Is the marine Lockne crater, Sweden, pristine?

NASA Astrophysics Data System (ADS)

Kenkmann, T.; Kiebach, F.; Rosenau, M.; Raschke, U.; Pigowske, A.; Mittelhaus, K.; Eue, D.

Our current understanding of marine-impact cratering processes is partly inferred from the geological structure of the Lockne crater. We present results of a mapping campaign and structural data indicating that this crater is not pristine. In the western part of the crater, pre-impact, impact, and post-impact rocks are incorporated in Caledonian thrust slices and are subjected to folding and faulting. A nappe outlier in the central crater depression is a relic of the Caledonian nappe cover that reached a thickness of more than 5 km. The overthrusted crater is gently deformed. Strike of strata and trend of fold axes deviate from standard Caledonian directions (northeast-southwest). Radially oriented crater depressions, which were previously regarded as marine resurge gullies formed when resurging seawater erosively cut through the crater brim, are interpreted to be open synclines in which resurge deposits were better preserved.The presence of the impact structure influenced orogenesis due to morphological and lithological anomalies of the crater: i) a raised crater brim zone acted as an obstacle during nappe propagation, (ii) the occurrence of a central crater depression caused downward sagging of nappes, and (iii) the lack of an appropriate detachment horizon (alum shale) within the crater led to an enhanced mechanical coupling and internal deformation of the nappe and the overthrusted foreland. Preliminary results of 3-D-analogue experiments suggest that a circular high-friction zone representing the crater locally hinders nappe propagation and initiates a circumferentially striking ramp fault that delineates the crater. Crustal shortening is also partitioned into the crater basement and decreases laterally outward. Deformation of the foreland affected the geometry of the detachment and could be associated with the activation of a deeper detachment horizon beneath the crater. Strain gradients both vertically and horizontally result in non-plane strain deformation

Assessing water resources under climate change in high-altitude catchments: a methodology and an application in the Italian Alps

NASA Astrophysics Data System (ADS)

Aili, T.; Soncini, A.; Bianchi, A.; Diolaiuti, G.; D'Agata, C.; Bocchiola, D.

2018-01-01

Assessment of the future water resources in the Italian Alps under climate change is required, but the hydrological cycle of the high-altitude catchments therein is poorly studied and little understood. Hydrological monitoring and modeling in the Alps is difficult, given the lack of first hand, site specific data. Here, we present a method to model the hydrological cycle of poorly monitored high-altitude catchments in the Alps, and to project forward water resources availability under climate change. Our method builds on extensive experience recently and includes (i) gathering data of climate, of cryospheric variables, and of hydrological fluxes sparsely available; (ii) robust physically based glacio-hydrological modeling; and (iii) using glacio-hydrological projections from GCM models. We apply the method in the Mallero River, in the central (Retiche) Alps of Italy. The Mallero river covers 321 km2, with altitude between 310 and 4015 m a.s.l., and it has 27 km2 of ice cover. The glaciers included in the catchment underwent large mass loss recently, thus Mallero is largely paradigmatic of the present situation of Alpine rivers. We set up a spatially explicit glacio-hydrological model, describing the cryospheric evolution and the hydrology of the area during a control run CR, from 1981 to 2007. We then gather climate projections until 2100 from three Global Climate Models of the IPCC AR5 under RCP2.6, RCP4.5, and RCP8.5. We project forward flow statistics, flow components (rainfall, snow melt, ice melt), ice cover, and volume for two reference decades, namely 2045-2054 and 2090-2099. We foresee reduction of the ice bodies from - 62 to - 98% in volume (year 2100 vs year 1981), and subsequent large reduction of ice melt contribution to stream flows (from - 61 to - 88%, 2100 vs CR). Snow melt, now covering 47% of the stream flows yearly, would also be largely reduced (from - 19 to - 56%, 2100 vs CR). The stream flows will decrease on average at 2100 (from + 1 to - 25

Bacteria at glacier surfaces: microbial community structures in debris covered glaciers and cryoconites in the Italian Alps

NASA Astrophysics Data System (ADS)

Azzoni, Roberto; Franzetti, Andrea; Ambrosini, Roberto; D'Agata, Carlo; Senese, Antonella; Minora, Umberto; Tagliaferri, Ilario; Diolaiuti, Guglielmina

2014-05-01

Supraglacial debris has an important role in the glacier energy budget and has strong influence on the glacial ecosystem. Sediment derives generally from rock inputs from nesting rockwalls and are abundant and continuous at the surface of debris-covered glaciers (i.e. DCGs; glaciers where the ablation area is mainly covered by rock debris) and sparse and fine on debris-free glaciers (DFGs). Recently, evidence for significant tongue darkening on retreating debris-free glaciers has been drawing increasing attention. Fine particles, the cryoconite, are locally abundant and may form cryoconite holes that are water-filled depressions on the surface of DFGs that form when a thin layer of cryoconite is heated by the sun and melts the underlying ice. There is increasing evidence that cryoconite holes also host highly diverse microbial communities and can significantly contribute to global carbon cycle. However, there is almost no study on microbial communities of the debris cover of DCGs and there is a lack of data from the temporal evolution of the microbial communities in the cryoconites. To fill these gaps in our knowledge we characterized the supraglacial debris of two Italian DCGs and we investigated the temporal evolution of microbial communities on cryoconite holes in DFG. We used the Illumina technology to analyse the V5 and V6 hypervariable regions of the bacterial 16S rRNA gene amplified from samples collected distances from the terminus of two DCGs (Miage and Belvedere Glaciers - Western Italian Alps). Heterotrophic taxa dominated bacterial communities, whose structure changed during downwards debris transport. Organic carbon of these recently exposed substrates therefore is probably provided more by allochthonous deposition of organic matter than by primary production by autotrophic organisms. We used ARISA fingerprinting and quantitative PCR to describe the structure and the evolution of the microbial communities and to estimate the number of the total

3-D structure of the crust and uppermost mantle at the junction between the Southeastern Alps and External Dinarides from ambient noise tomography

NASA Astrophysics Data System (ADS)

Guidarelli, Mariangela; Aoudia, Abdelkrim; Costa, Giovanni

2017-12-01

We use ambient noise tomography to investigate the crust and the uppermost mantle structure beneath the junction between the Southern Alps, the Dinarides and the Po Plain. We obtained Rayleigh wave empirical Green's functions from cross-correlation of vertical component seismic recordings for three years (2010-2012) using stations from networks in Italy, Slovenia, Austria, Croatia, Serbia and Switzerland. We measure group and phase velocity dispersion curves from the reconstructed Rayleigh waves in the period range 5-30 and 8-37 s, respectively, and we invert the surface wave velocities for tomographic images on a grid of 0.1° × 0.1°. After the tomography, the group velocities are then inverted to compute the 3-D shear wave velocity model of the crust and the upper mantle beneath the region. Our shear wave velocity model provides the 3-D image of the structure in the region between Northeastern Italy, Slovenia and Austria. The velocity variations at shallow depths correlate with known geological and tectonic domains. We find low velocities below the Po Plain, the northern tip of the Adriatic and the Pannonian Basin, whereas higher velocities characterize the Alpine chain. The vertical cross-sections reveal a clear northward increase of the crustal thickness with a sharp northward dipping of the Moho that coincides at the surface with the leading edge of the Alpine thrust front adjacent to the Friuli Plain in Northeastern Italy. This geometry of the Moho mimics fairly well the shallow north dipping geometry of the decollement inferred from permanent GPS velocity field where high interseismic coupling is reported. From the northern Adriatic domain up to the Idrija right lateral strike-slip fault system beneath Western Slovenia, the crustal thickness is more uniform. Right across Idrija fault, to the northeast, and along its strike, we report a clear change of the physical properties of the crust up to the uppermost mantle as reflected by the lateral distribution

Recent slope failures in the Dolomites (Northeastern Italian Alps) in a context of climate change

NASA Astrophysics Data System (ADS)

Chiarle, Marta; Paranunzio, Roberta; Laio, Francesco; Nigrelli, Guido; Guzzetti, Fausto

2014-05-01

Climate change in the Greater Alpine Region is seriously affecting permafrost distribution, with relevant consequences on slope stability. In the Italian Alps, the number of failures from rockwalls at high elevation markedly increased in the last 20-30 years: the consistent temperature increase, which warmed twice than the global average, may have seriously influenced slope stability, in terms of glaciers retreat and permafrost degradation. Moreover, the growing number of tourists and activities in alpine regions (in particular in the Dolomites) made these areas particularly critical in relation to natural hazards. In this light, an integrated short-term geomorphological and climatic analysis was performed, in order to better comprehend the impact of main climate elements (especially temperature and precipitation) on slope failures in high mountain areas. In this contribution, we focus on three recent slope failures occurred at high elevation sites in the Dolomites (Northeastern Italian Alps), declared a UNESCO World Heritage Site in August 2009. We describe here three important rock falls occurred in the autumn 2013: 1) the Sorapiss rock fall, on 30 September 2013; 2) the Monte Civetta rock fall, on 16 November 2013; 3) the Monte Antelao rock fall, on 22 November 2013. The Monte Civetta rock fall damaged some climbing routes, while the other two landslides did not cause any damage or injury. Despite the limited volume involved, these three events represent an important warning sign in the context of ongoing climate change. Geomorphological information about the rock fall sites were combined with the climatic data acquired from the meteorological stations surrounding the slope failure areas. A short-term climatic analysis was performed, with the aim of understanding the role of the main climatic elements in the triggering of natural instability events in this area and in the Alps in general.

How well do we really know the timing and extent of glaciers during the Last Glacial Maximum in the Alps?

NASA Astrophysics Data System (ADS)

Ivy-Ochs, Susan; Braakhekke, Jochem; Monegato, Giovanni; Gianotti, Franco; Forno, Gabriella; Hippe, Kristina; Christl, Marcus; Akçar, Naki; Schluechter, Christian

2017-04-01

The Last Glacial Maximum (LGM) in the Alps saw much of the mountains inundated by ice. Several main accumulation areas comprising local ice caps and plateau icefields fit into a picture of transection glaciers flowing into huge valley glaciers. In the north the valley glaciers covered long distances (hundreds of kilometers) to reach the forelands where they spread out in fan-shaped piedmont lobes tens of kilometers across, e.g. the Rhine glacier. In the south travel distances to the mountain front were often shorter, the pathway steeper. Nevertheless, not all glaciers even reached beyond the front, as the temperatures were notably warmer in the south. For example at Orta the glacier snout remained within the mountains. Where glaciers reached the forelands they stopped abruptly and the moraine amphitheaters were constructed, e.g. at Ivrea and Rivoli-Avigliana. Sets of stacked moraines built-up as glacier advance was directly confined by the older moraines. We may temporally and spatially identify the culmination of the last glacial cycle by pinpointing the outermost moraines that date to the LGM (generally about 26-24 ka). On the other hand, the timing of abandonment of foreland positions is given by ages of the innermost, often lake-bounding, moraines (about 19-18 ka). Between the two, glacier fluctuations left the stadial moraines. In the Linth-Rhine system three stadials have been recognized: Killwangen, Schlieren and Zurich. Nevertheless, already in the Swiss sector correlation of the LGM stadials among the several foreland lobes is not unambiguous. Across the Alps, not only north to south but also west to east, how do the timing and extent of glaciers during the LGM vary? Recent glacier modelling by Seguinot et al. (2017) informs and suggests the possibility of differences in timing for reaching of the maximum extent and for the number of oscillations of individual lobes during the LGM. At present few sites in the Alps have detailed enough geomorphological

A petro-structural review of the Zermatt-Saas Fee zone

NASA Astrophysics Data System (ADS)

Schenker, Filippo Luca; Markus Schmalholz, Stefan; Baumgartner, Lukas

2014-05-01

The Zermatt-Saas Fee zone (ZSZ) is an imbricate of fragments of blueschist- to eclogite-facies metabasalts and metagabbros, serpentinites and mélange zones containing blocks of the above mentioned rocks. The ZSZ is usually interpreted as a fragment of oceanic crust belonging to the Piemont-Ligurian (Tethyan) Ocean that was accreted into the Alpine nappe pile. In the last decades the discovery of several Ultra-High Pressure (UHP, >2.7 GPa at 550-600 °C from coesite bearing eclogites and diamond-bearing fluid inclusions in garnet) localities lead to the interpretation of deep subduction (> 100 km) of the ZSZ in the Eocene, and subsequent uplift from mantle depth with high exhumation rates (e.g. Amato et al., 1999). However, these high pressures are in apparent contrast to the regional metamorphic conditions that reflect pressures peaking at < 2 GPa for 550-600°C (blueschist and eclogite mineral assemblages in mafic rocks). These latter metamorphic conditions do not need anomalous high burial histories and exhumation velocities higher than the plate velocities. The magnitude and distribution of pressure in the tectonic units of the ZSZ are important for constraining dynamic models for the evolution of the ZSZ and the Western Alps. Before entering into dynamic models, we propose a petro-structural overview where the published petrological data on pressure and temperature are critically reviewed, and positioned on a geological map and cross section in order to integrate them into the proper structural and tectonic framework. The questions we seek to answer are: How is the pressure distributed within the main tectonic units and within the entire ZSZ? Do we observe sharp or gradual pressure gradients within the ZSZ? Can the UHP conditions be averaged/extended to the entire ZSZ? If not, do they correspond to conditions of observable subunits, or do they reflect anomalies in the pressure field? Answering these questions is fundamental to better understand the

Evidence for enhanced debris-flow activity in the Northern Calcareous Alps since the 1980s (Plansee, Austria)

NASA Astrophysics Data System (ADS)

Dietrich, A.; Krautblatter, M.

2017-06-01

Debris flows are among the most important natural hazards. The Northern Calcareous Alps with their susceptible lithology are especially affected by a double digit number of major hazard events per year. It is hypothesised that debris-flow intensity has increased significantly in the last decades in the Northern Calcareous Alps coincident to increased rainstorm frequencies, but yet there is only limited evidence. The Plansee catchment exposes extreme debris-flow activity due to the intensely jointed Upper Triassic Hauptdolomit lithology, being responsible for most of the debris-flow activity in the Northern Calcareous Alps. The debris flows feed into a closed sediment system, the Plansee Lake, where Holocene/Lateglacial sedimentation rates, rates since the late 1940s and recent rates can be inferred accurately. Using aerial photos and field mapping, the temporal and spatial development of eight active debris-flow fans is reconstructed in six time intervals from 1947, 1952, 1971, 1979, 1987, 2000 and 2010 and mean annual debris-flow volumes are calculated. These are compared with mean Holocene/Lateglacial debris-flow volumes derived from the most prominent cone whose contact with the underlying till is revealed by electrical resistivity tomography (ERT). Debris-flow activity there increased by a factor of 10 from 1947-1952 (0.23 ± 0.07 · 103 m3/yr) to 1987-2000 (2.41 ± 0.66 · 103 m3/yr). Mean post-1980 rates from all eight fans exceed pre-1980 rates by a factor of more than three coinciding with enhanced rainstorm activity recorded at meteorological stations in the Northern Calcareous Alps. The frequency of rain storms (def. 35 mm/d) has increased in the study area on average by 10% per decade and has nearly doubled since 1921. Recent debris-flow activity is also 2-3 times higher than mean Holocene/Lateglacial rates. The strong correlation between the non-vegetated catchment area and the annual debris-flow volume might indicate a decadal positive feedback between

MAPK Signaling Pathway Alters Expression of Midgut ALP and ABCC Genes and Causes Resistance to Bacillus thuringiensis Cry1Ac Toxin in Diamondback Moth

PubMed Central

Wu, Qingjun; Wang, Shaoli; Xie, Wen; Zhu, Xun; Baxter, Simon W.; Zhou, Xuguo; Jurat-Fuentes, Juan Luis; Zhang, Youjun

2015-01-01

Insecticidal crystal toxins derived from the soil bacterium Bacillus thuringiensis (Bt) are widely used as biopesticide sprays or expressed in transgenic crops to control insect pests. However, large-scale use of Bt has led to field-evolved resistance in several lepidopteran pests. Resistance to Bt Cry1Ac toxin in the diamondback moth, Plutella xylostella (L.), was previously mapped to a multigenic resistance locus (BtR-1). Here, we assembled the 3.15 Mb BtR-1 locus and found high-level resistance to Cry1Ac and Bt biopesticide in four independent P. xylostella strains were all associated with differential expression of a midgut membrane-bound alkaline phosphatase (ALP) outside this locus and a suite of ATP-binding cassette transporter subfamily C (ABCC) genes inside this locus. The interplay between these resistance genes is controlled by a previously uncharacterized trans-regulatory mechanism via the mitogen-activated protein kinase (MAPK) signaling pathway. Molecular, biochemical, and functional analyses have established ALP as a functional Cry1Ac receptor. Phenotypic association experiments revealed that the recessive Cry1Ac resistance was tightly linked to down-regulation of ALP, ABCC2 and ABCC3, whereas it was not linked to up-regulation of ABCC1. Silencing of ABCC2 and ABCC3 in susceptible larvae reduced their susceptibility to Cry1Ac but did not affect the expression of ALP, whereas suppression of MAP4K4, a constitutively transcriptionally-activated MAPK upstream gene within the BtR-1 locus, led to a transient recovery of gene expression thereby restoring the susceptibility in resistant larvae. These results highlight a crucial role for ALP and ABCC genes in field-evolved resistance to Cry1Ac and reveal a novel trans-regulatory signaling mechanism responsible for modulating the expression of these pivotal genes in P. xylostella. PMID:25875245

Interseismic coupling, seismic potential, and earthquake recurrence on the southern front of the Eastern Alps (NE Italy)

NASA Astrophysics Data System (ADS)

Cheloni, D.; D'Agostino, N.; Selvaggi, G.

2014-05-01

Here we use continuous GPS observations to document the geodetic strain accumulation across the South-Eastern Alps (NE Italy). We estimate the interseismic coupling on the intracontinental collision thrust fault and discuss the seismic potential and earthquake recurrence. We invert the GPS velocities using the back slip approach to simultaneously estimate the relative angular velocity and the degree of interseismic coupling on the thrust fault that separates the Eastern Alps and the Venetian-Friulian plain. Comparison between the rigid rotation predicted motion and the shortening observed across the area indicates that the South-Eastern Alpine thrust front absorbs about 70% of the total convergence between the Adria and Eurasia plates. The coupling is computed on a north dipping fault following the continuous external seismogenic thrust front of the South-Eastern Alps. The modeled thrust fault is currently locked from the surface to a depth of ≈10 km. The transition zone between locked and creeping portions of the fault roughly corresponds with the belt of microseismicity parallel and to the north of the mountain front. The estimated moment deficit rate is 1.3 ± 0.4 × 1017 Nm/yr. The comparison between the estimated moment deficit and that released historically by the earthquakes suggests that to account for the moment deficit the following two factors or their combination should be considered: (1) a significant part of the observed interseismic coupling is released aseismically and (2) infrequent "large" events with long return period (> 1000 years) and with magnitudes larger than the value assigned to the largest historical events (Mw≈ 6.7).

Late Pleistocene - Holocene surface processes and landscape evolution in the central Swiss Alps

NASA Astrophysics Data System (ADS)

Boxleitner, Max; Musso, Alessandra; Waroszewski, Jarosław; Malkiewicz, Małgorzata; Maisch, Max; Dahms, Dennis; Brandová, Dagmar; Christl, Marcus; de Castro Portes, Raquel; Egli, Markus

2017-10-01

The European Alps are a geomorphologically active region and experience a number of gravity-driven hillslope processes. Soil and landscape formation in the Alps has consequently undergone several minor and major traceable changes of developmental trajectories during the Holocene. Soil development is hypothesised to be often non-linear with time and characterised by stages of progressive and regressive evolution caused by upbuilding (formation, profile deepening) and erosion (profile shallowing). Several cold and warm climate phases are identified during the Holocene but it is largely unknown which effects these might have had on slope processes. By using datable moraines (10Be) and mires (14C), we have constructed a temporal framework for these processes. Using the geochemical imprint of mires in the Alpine setting of the Göschener-valley of the Central Swiss Alps, we reconstructed general (mostly erosional) landscape processes for the last ca. 10 ka. As this is the type locality for the Göschener cold phase, we assumed that this phase (Göschener cold phase I and II 1.5 and 2.5 ka BP) should have left easily recognizable traits. After deglaciation (11-12 ka BP), soil evolution was progressive. Beginning around 8 ka BP, we detect a distinct increase in erosion here, together with a vegetation change (towards tundra vegetation) and the highest measured rates of carbon sequestration. Other phases of high geomorphic activity were recognised ca. 5-6 ka BP, 4 ka BP and, to a lesser extent, 1-3 ka ago. The cold phase at 5-6 ka BP corresponds to a less distinct change in vegetation and lessened erosion. Human impact is increasingly obvious since about 2.4 ka BP which overlaps with the Göschener cold phase. Nonetheless, erosion processes were not extraordinarily high during this period and a climate effect cannot be distinguished. We detect evidence of increasing human disturbance (regressive soil evolution) for about the last 1 ka. We also detect an increase in dust

Accelerating climate change impacts on alpine glacier forefield ecosystems in the European Alps.

PubMed

Cannone, Nicoletta; Diolaiuti, Guglielmina; Guglielmin, Mauro; Smiraglia, Claudio

2008-04-01

In the European Alps the increase in air temperature was more than twice the increase in global mean temperature over the last 50 years. The abiotic (glacial) and the biotic components (plants and vegetation) of the mountain environment are showing ample evidence of climate change impacts. In the Alps most small glaciers (80% of total glacial coverage and an important contribution to water resources) could disappear in the next decades. Recently climate change was demonstrated to affect higher levels of ecological systems, with vegetation exhibiting surface area changes, indicating that alpine and nival vegetation may be able to respond in a fast and flexible way in response to 1-2 degrees C warming. We analyzed the glacier evolution (terminus fluctuations, mass balances, surface area variations), local climate, and vegetation succession on the forefield of Sforzellina Glacier (Upper Valtellina, central Italian Alps) over the past three decades. We aimed to quantify the impacts of climate change on coupled biotic and abiotic components of high alpine ecosystems, to verify if an acceleration was occurring on them during the last decade (i.e., 1996-2006) and to assess whether new specific strategies were adopted for plant colonization and development. All the glaciological data indicate that a glacial retreat and shrinkage occurred and was much stronger after 2002 than during the last 35 years. Vegetation started to colonize surfaces deglaciated for only one year, with a rate at least four times greater than that reported in the literature for the establishment of scattered individuals and about two times greater for the well-established discontinuous early-successional community. The colonization strategy changed: the first colonizers are early-successional, scree slopes, and perennial clonal species with high phenotypic plasticity rather than pioneer and snowbed species. This impressive acceleration coincided with only slight local summer warming (approximately -0

Impact of droughts on water provision in managed alpine grasslands in two climatically different regions of the Alps.

PubMed

Leitinger, Georg; Ruggenthaler, Romed; Hammerle, Albin; Lavorel, Sandra; Schirpke, Uta; Clement, Jean-Christophe; Lamarque, Pénélope; Obojes, Nikolaus; Tappeiner, Ulrike

2015-12-01

This study analyzes the impact of droughts, compared with average climatic conditions, on the supporting ecosystem service water provision in sub-watersheds in managed alpine grasslands in two climatically different regions of the Alps, Lautaret (French Alps) and Stubai (Austrian Alps). Soil moisture was modelled in the range of 0-0.3 m. At both sites, current patterns showed that the mean seasonal soil moisture was (1) near field capacity for grasslands with low management intensity and (2) below field capacity for grasslands with higher land-use intensity. Soil moisture was significantly reduced by drought at both sites, with lower reductions at the drier Lautaret site. At the sub-watershed scale, soil moisture spatial heterogeneity was reduced by drought. Under drought conditions, the evapotranspiration to precipitation ratios at Stubai was slightly higher than those at Lautaret, indicating a dominant 'water spending' strategy of plant communities. Regarding catchment water balance, deep seepage was reduced by drought at Stubai more strongly than at Lautaret. Hence, the observed 'water spending' strategy at Stubai might have negative consequences for downstream water users. Assessing the water provision service for alpine grasslands provided evidence that, under drought conditions, evapotranspiration was influenced not only by abiotic factors but also by the water-use strategy of established vegetation. These results highlight the importance of 'water-use' strategies in existing plant communities as predictors of the impacts of drought on water provision services and related ecosystem services at both the field and catchment scale.

Application of Powder Diffraction Methods to the Analysis of the Atomic Structure of Nanocrystals: The Concept of the Apparent Lattice Parameter (ALP)

NASA Technical Reports Server (NTRS)

Palosz, B.; Grzanka, E.; Gierlotka, S.; Stelmakh, S.; Pielaszek, R.; Bismayer, U.; Weber, H.-P.; Palosz, W.; Curreri, Peter A. (Technical Monitor)

2002-01-01

The applicability of standard methods of elaboration of powder diffraction data for determination of the structure of nano-size crystallites is analysed. Based on our theoretical calculations of powder diffraction data we show, that the assumption of the infinite crystal lattice for nanocrystals smaller than 20 nm in size is not justified. Application of conventional tools developed for elaboration of powder diffraction data, like the Rietveld method, may lead to erroneous interpretation of the experimental results. An alternate evaluation of diffraction data of nanoparticles, based on the so-called 'apparent lattice parameter' (alp) is introduced. We assume a model of nanocrystal having a grain core with well-defined crystal structure, surrounded by a surface shell with the atomic structure similar to that of the core but being under a strain (compressive or tensile). The two structural components, the core and the shell, form essentially a composite crystal with interfering, inseparable diffraction properties. Because the structure of such a nanocrystal is not uniform, it defies the basic definitions of an unambiguous crystallographic phase. Consequently, a set of lattice parameters used for characterization of simple crystal phases is insufficient for a proper description of the complex structure of nanocrystals. We developed a method of evaluation of powder diffraction data of nanocrystals, which refers to a core-shell model and is based on the 'apparent lattice parameter' methodology. For a given diffraction pattem, the alp values are calculated for every individual Bragg reflection. For nanocrystals the alp values depend on the diffraction vector Q. By modeling different a0tomic structures of nanocrystals and calculating theoretically corresponding diffraction patterns using the Debye functions we showed, that alp-Q plots show characteristic shapes which can be used for evaluation of the atomic structure of the core-shell system. We show, that using a simple

Carbonation of subduction-zone serpentinite (high-pressure ophicarbonate; Ligurian Western Alps) and implications for the deep carbon cycling

NASA Astrophysics Data System (ADS)

Scambelluri, Marco; Bebout, Gray E.; Belmonte, Donato; Gilio, Mattia; Campomenosi, Nicola; Collins, Nathan; Crispini, Laura

2016-05-01

Much of the long-term carbon cycle in solid earth occurs in subduction zones, where processes of devolatilization, partial melting of carbonated rocks, and dissolution of carbonate minerals lead to the return of CO2 to the atmosphere via volcanic degassing. Release of COH fluids from hydrous and carbonate minerals influences C recycling and magmatism at subduction zones. Contradictory interpretations exist regarding the retention/storage of C in subducting plates and in the forearc to subarc mantle. Several lines of evidence indicate mobility of C, of uncertain magnitude, in forearcs. A poorly constrained fraction of the 40-115 Mt/yr of C initially subducted is released into fluids (by decarbonation and/or carbonate dissolution) and 18-43 Mt/yr is returned at arc volcanoes. Current estimates suggest the amount of C released into subduction fluids is greater than that degassed at arc volcanoes: the imbalance could reflect C subduction into the deeper mantle, beyond subarc regions, or storage of C in forearc/subarc reservoirs. We examine the fate of C in plate-interface ultramafic rocks, and by analogy serpentinized mantle wedge, via study of fluid-rock evolution of marble and variably carbonated serpentinite in the Ligurian Alps. Based on petrography, major and trace element concentrations, and carbonate C and O isotope compositions, we demonstrate that serpentinite dehydration at 2-2.5 GPa, 550 °C released aqueous fluids triggering breakdown of dolomite in nearby marbles, thus releasing C into fluids. Carbonate + olivine veins document flow of COH fluids and that the interaction of these COH fluids with serpentinite led to the formation of high-P carbonated ultramafic-rock domains (high-P ophicarbonates). We estimate that this could result in the retention of ∼0.5-2.0 Mt C/yr in such rocks along subduction interfaces. As another means of C storage, 1 to 3 km-thick layers of serpentinized forearc mantle wedge containing 50 modal % dolomite could sequester 1.62 to

Seismic imaging of the geodynamic activity at the western Eger rift in central Europe

NASA Astrophysics Data System (ADS)

Mullick, N.; Buske, S.; Hrubcova, P.; Ruzek, B.; Shapiro, S.; Wigger, P.; Fischer, T.

2015-04-01

The western Eger rift at the Czech-German border in central Europe is an important geodynamically active area within the European Cenzoic rift system (ECRS) in the forelands of the Alps. Along with two other active areas of the ECRS, the French Massif Central and the east and west Eifel volcanic fields, it is characterized by numerous CO2-rich fluid emission points and frequent micro-seismicity. Existence of a plume(s) is indicated in the upper mantle which may be responsible for these observations. Here we reprocess a pre-existing deep seismic reflection profile '9HR' and interpret the subsurface structures as mapped by seismic reflectivity with previous findings, mainly from seismological and geochemical studies, to investigate the geodynamic activity in the subsurface. We find prominent hints of pathways which may allow magmatic fluids originating in the upper mantle to rise through the crust and cause the observed fluid emanations and earthquake activity.

10Be exposure age chronology of the last glaciation of the Roháčská Valley in the Western Tatra Mountains, central Europe

NASA Astrophysics Data System (ADS)

Engel, Zbyněk; Mentlík, Pavel; Braucher, Régis; Křížek, Marek; Pluháčková, Markéta; Arnold, Maurice; Aumaître, Georges; Bourlès, Didier; Keddadouche, Karim; Aster Team; Arnold, Maurice; Aumaître, Georges; Bourlès, Didier; Keddadouche, Karim

2017-09-01

10Be exposure ages from moraines and bedrock sites in the Roháčská Valley provide chronology of the last glaciation in the largest valley of the Western Tatra Mts., the Western Carpathians. The minimum apparent exposure age of 19.4 ± 2.1 ka obtained for the oldest sampled boulder and the mean age of 18.0 ± 0.8 ka calculated for the terminal moraine indicate that the oldest preserved moraine was probably deposited at the time of the global Last Glacial Maximum (LGM). The age of this moraine coincides with the termination of the maximum glacier expansion in other central European ranges, including the adjacent High Tatra Mts. and the Alps. The equilibrium line altitude (ELA) of the LGM glacier in the Roháčská Valley, estimated at 1400-1410 m a.s.l., was 50-80 m lower than in the eastern part of the range, indicating a positive ELA gradient from west to east among the north-facing glaciers in the Tatra Mts. Lateglacial glacier expansion occurred no later than 13.4 ± 0.5 ka and 11.9 ± 0.5 ka, as indicated by the mean exposure ages calculated for re-advance moraines. This timing is consistent with the exposure age chronology of the last Lateglacial re-advance in the High Tatra Mts., Alps and lower mountain ranges in central Europe. The ELA in the Roháčská Valley estimated at 1690-1770 m a.s.l. in this period was located 130-300 m lower than in the north-facing valleys in the High Tatra Mts. 10Be exposure ages obtained for a rock glacier constrains the timing of this landform stabilization in the Salatínska Valley and provides the first chronological evidence for the Lateglacial activity of rock glaciers in the Carpathians.

21st century climate change in the European Alps--a review.

PubMed

Gobiet, Andreas; Kotlarski, Sven; Beniston, Martin; Heinrich, Georg; Rajczak, Jan; Stoffel, Markus

2014-09-15

Reliable estimates of future climate change in the Alps are relevant for large parts of the European society. At the same time, the complex Alpine region poses considerable challenges to climate models, which translate to uncertainties in the climate projections. Against this background, the present study reviews the state-of-knowledge about 21st century climate change in the Alps based on existing literature and additional analyses. In particular, it explicitly considers the reliability and uncertainty of climate projections. Results show that besides Alpine temperatures, also precipitation, global radiation, relative humidity, and closely related impacts like floods, droughts, snow cover, and natural hazards will be affected by global warming. Under the A1B emission scenario, about 0.25 °C warming per decade until the mid of the 21st century and accelerated 0.36 °C warming per decade in the second half of the century is expected. Warming will probably be associated with changes in the seasonality of precipitation, global radiation, and relative humidity, and more intense precipitation extremes and flooding potential in the colder part of the year. The conditions of currently record breaking warm or hot winter or summer seasons, respectively, may become normal at the end of the 21st century, and there is indication for droughts to become more severe in the future. Snow cover is expected to drastically decrease below 1500-2000 m and natural hazards related to glacier and permafrost retreat are expected to become more frequent. Such changes in climatic parameters and related quantities will have considerable impact on ecosystems and society and will challenge their adaptive capabilities. © 2013. Published by Elsevier B.V. All rights reserved.

Fluid-rock reactions in an evaporitic melange, Permian Haselgebirge, Austrian Alps

USGS Publications Warehouse

Spotl, C.; Longstaffe, F.J.; Ramseyer, K.; Kunk, Michael J.; Wiesheu, R.

1998-01-01

Tectonically isolated blocks of carbonate rocks present within the anhydritic Haselgebirge melange of the Northern Calcareous Alps record a complex history of deformation and associated deep-burial diagenetic to very low-grade metamorphic reactions. Fluids were hot (up to ~ 250 ??C) and reducing brines charged with carbon dioxide. Individual carbonate outcrops within the melange record different regimes of brine-rock reactions, ranging from pervasive dolomite recrystallization to dedolomitization. Early diagenetic features in these carbonates were almost entirely obliterated. Matrix dolomite alteration was related to thermochemical sulphate reduction (TSR) recognized by the replacement of anhydrite by calcite + pyrite ?? native sulphur. Pyrite associated with TSR is coarsely crystalline and characterized by a small sulphur isotope fractionation relative to the precursor Permian anhydrite. Carbonates associated with TSR show low Fe/Mn ratios reflecting rapid reaction of ferrous iron during sulphide precipitation. As a result, TSR-related dolomite and calcite typically show bright Mn(II)-activated cathodoluminescence in contrast to the dull cathodoluminescence of many (ferroan) carbonate cements in other deep-burial settings. In addition to carbonates and sulphides, silicates formed closely related to TSR, including quartz, K-feldspar, albite and K-mica. 40Ar/39Ar analysis of authigenic K-feldspar yielded mostly disturbed step-heating spectra which suggest variable cooling through the argon retention interval for microcline during the Late Jurassic. This timing coincides with the recently recognized subduction and closure of the Meliata-Hallstatt ocean to the south of the Northern Calcareous Alps and strongly suggests that the observed deep-burial fluid-rock reactions were related to Jurassic deformation and melange formation of these Permian evaporites.

Spatial organization of seismicity and fracture pattern at the boundary between Alps and Dinarides

NASA Astrophysics Data System (ADS)

Bressan, Gianni; Ponton, Maurizio; Rossi, Giuliana; Urban, Sandro

2016-04-01

The paper affords the study of the spatial organization of seismicity in the easternmost region of the Alps (Friuli, in NE Italy and W Slovenia), dominated by the interference between the Alpine and the Dinaric tectonic systems. Two non-conventional methods of spatial analysis are used: fractal analysis and principal component analysis (PCA). The fractal analysis helps to discriminate the cases in which hypocentres clearly define a plane, from the ones in which hypocenter distribution tends to the planarity, without reaching it. The PCA analysis is used to infer the orientation of planes fitting through earthquake foci, or the direction of propagation of the hypocentres. Furthermore, we study the spatial seismicity pattern at the shallow depths in the context of a general damage model, through the crack density distribution. The results of the three methods concur to a complex and composite model of fracturing in the region. The hypocentre pattern fills only partially a plane, i.e. has a fractal dimension close to 2. The three exceptions regard planes with Dinaric trend, without interference with Alpine lineaments. The shallowest depth range (0-10 km depth) is characterized by the activation of planes with variable orientations, reflecting the interference between the Dinaric and the Alpine tectonic structures, and closely bound to the variation of the mechanical properties of the crust. The seismicity occurs mostly in areas characterized by a variation from low to moderate crack density, indicating the sharp transition from zones of low damage to zones of moderate damage. Low crack density indicates the presence of more competent rocks capable of sustaining high strain energy while high crack density areas pertain to highly fractured rocks that cannot store high strain energy. Brittle failure, i.e. seismic activity, is favoured within the sharp transitions from low to moderate crack density zones. The orientation of the planes depicting the seismic activity

Bringing dust to good use: Quartz OSL ante-quam dating of the Strassberg rock avalanche (Northern Calcareous Alps, Austria) and implications for chronostratigraphic resolution of post-glacial deposits

NASA Astrophysics Data System (ADS)

Gild, Charlotte; Geitner, Clemens; Sanders, Diethard

2017-04-01

The Mieming massif in the western part of the Northern Calcareous Alps (NCA, Austria) records a complex history of rapid landscape change during the deglacial to paraglacial phase (c. 19.5-17 ka) after the Last Glacial Maximum (LGM). In this succession of changes, a major event that shaped the entire catchment till today was the descend of a rock avalanche of a GIS-estimated volume of 11 Mm3. This rock avalanche: (a) clogged a pre-existing valley, (b) dammed up an intramontane basin (Strassberg basin), and (c) triggered the incision of an epigenetic bedrock gorge some 1.5 km in length (Sanders et al., 2016). Geomorphological and sedimentological indicators all suggest that the rock avalanche descended very soon after local deglaciation, but an age estimate of mass-wasting was difficult to provide. Bulk radiocarbon ages of the acid-washed, humic fraction of soil horizons intercalated into colluvium above the rock avalanche deposit indicated an oldest age of 11180-11170 a cal BP; a large scatter of radiocarbon ages (youngest: 7960 a cal BP; oldest: 11180 a cal BP; total of three ages) indicated that these well-drained soils were subject to input of younger humic substance, thus can provide only a crude proxy ante-quam date for the event. Over the past two years, in the NCA, a landscape-wide drape of polymictic siliciclastic aeolian silt was discovered that - as suggested by its geomorphic and sedimentary context - most probably was deposited during the late-glacial chron. The drape is verified over a vertical relief amplitude of more than 2000 meters, from valley floors up to LGM nunataks (Gild et al., 2016). A level of polymictic siliciclastic silt was found also directly on top of the Strassberg rock avalanche deposit. This provided an opportunity to deduce a more precise ante-quam quartz OSL age of 18.77 ± 1.55 ka for mass-wasting. The high post-glacial event age is consistent with evidence that the clearing of the older trunk valley from LGM sediments was just

Structure and evolution of a rocksalt-mudrock-tectonite: The haselgebirge in the Northern Calcareous Alps.

PubMed

Leitner, Christoph; Neubauer, Franz; Urai, János L; Schoenherr, Johannes

2011-05-01

The Northern Calcareous Alps are part of the Eastern Alps in Austria and Germany. The Mesozoic units of this fold-and-thrust belt were detached, thrusted and stacked along the evaporitic Haselgebirge Formation. Exposed in salt mines, rocksalt and mudrock form a two component tectonite: The rock type "haselgebirge" consists of 10-70 wt % halite with silt- to gravel- or block-sized components within a halite matrix, and the "kerngebirge" with >70 wt % halite. All rock types studied are fault rocks. By use of a temperature-independent subgrain size piezometer, the paleo-differential stress of halite was calculated at ca. 2.5 MPa in Altaussee and ca. 4.5 MPa in Berchtesgaden. Including data from a grain-size piezometer, temperatures were estimated at ca. 150 ± 20 °C and 110 ± 10 °C. This implies very high strain rates, which are about 10 -10 -10 -9  s -1 . During the tectonic movement, the halite deformed, recrystallized, and crystallized as veins in mudrock fractures. We interpret high overpressure of the pore fluid to have significantly contributed to fracturing of the mudrock.

Saharan dust particles in snow samples of Alps and Apennines during an exceptional event of transboundary air pollution.

PubMed

Telloli, Chiara; Chicca, Milvia; Pepi, Salvatore; Vaccaro, Carmela

2017-12-21

Southern European countries are often affected in summer by transboundary air pollution from Saharan dust. However, very few studies deal with Saharan dust pollution at high altitudes in winter. In Italy, the exceptional event occurred on February 19, 2014, colored in red the entire mountain range (Alps and Apennines) and allowed to characterize the particulate matter deposited on snow from a morphological and chemical point of view. Snow samples were collected after this event in four areas in the Alps and one in the Apennines. The particulate matter of the melted snow samples was analyzed by scanning electron microscopy with energy dispersive X-ray spectrometry (SEM-EDS) and by inductively coupled plasma mass spectrometry (ICP-MS). These analyses confirmed the presence of Saharan dust particle components in all areas with similar percentages, supported also by the positive correlations between Mg-Ca, Al-Ca, Al-Mg, and Al-K in all samples.

Holocene Mass Transport Deposits in Western Norwegian fjords and lakes revealing prehistoric earthquake history of Scandinavia

NASA Astrophysics Data System (ADS)

Bellwald, B.; Hjelstuen, B. O.; Sejrup, H. P.; Kuvås, J.; Stokowy, T.

2016-12-01

The sensitivity of fjord sediments to seismic shaking makes fjord systems appropriate study sites when extending regional earthquake catalogs back in time and when estimating recurrence rates of prehistoric earthquakes in intraplate settings. In this study we compiled evidence of 140 postglacial mass movement events and their associated mass transport deposits (MTDs) from previously analyzed and new sediment cores and high-resolution seismic profiles from 22 fjord systems and six lakes in Western Norway. Evaluation of trigger mechanisms make us infer that most of these mass movement events were initiated by regional earthquakes, and that both climate-related processes and tsunamis most likely can be excluded as trigger mechanism for most of the events. A total of 33 individual earthquakes has been identified, which most likely outbalance the historically recorded events in magnitude, thus indicating magnitudes >6. Frequency plots of MTDs suggest high seismic activity in the early Holocene (11000-9700 cal. yrs BP), followed by seismic quiescence in the mid-Holocene before a seismic reactivation took place at 4000 cal. yrs BP. Coevally-triggered MTDs at 8100 cal. yrs BP are identified in all the archives, and are correlating with the age of the offshore Storegga slide. We estimate earthquake recurrence rates of 1/80 years directly after the last deglaciation of Western Norway (12800-11600 ca. yrs BP), 1/200 years for the early Holocene and 1/300 years for the last 4000 years. Our compilation suggests that the mid-Holocene is characterized by low seismic activity, suggesting recurrence rates of 1/1300 years. Comparisons of the Western Norwegian dataset with paleoseimologic studies of other previously glaciated intraplate settings indicate that both Scandinavia and the Alps show similar trends as Western Norway, whereas Eastern Canada is not correlating with the paleoseismologic trend of this study, which could be explained by different deglaciation histories.

New lakes in deglaciating high-mountain areas: Regional intercomparison of current and future risks from impact waves due to rock/ice avalanches in the Swiss Alps

NASA Astrophysics Data System (ADS)

Schaub, Y.; Huggel, C.; Serraino, M.; Haeberli, W.

2012-04-01

The changes in high-mountain environments are increasingly fast and complex. GIS-based models of the Swiss Alps show that numerous topographic overdeepenings are likely to appear on progressively exposed glacier beds, which are considered as potential sites of future lake formation. In many cases these newly forming lakes will be situated in an over-steepened and destabilized high-mountain environment and are, therefore, prone to impact waves from landslides. The risk of glacier lake outburst floods, endangering infrastructure, residential areas and persons further downvalley, is increasing with further lake formation and glacier recession. This risk may persist for many decades if not centuries. Future-oriented hazard assessments have to be integrative and must deal with all possible process chains. Reference studies and methodologies are still scarce, however. We present an approach to compare risks resulting from high-mountain lakes in the Swiss Alps amongst each other. Already existing lakes are thereby as much included in the analysis as future ones. The presented risk assessment approach integrates the envisaged high-mountain hazard process chain with present and future socio-economic conditions. Applying the concept of integral risk management, the hazard and damage potentials have to be analyzed. The areas that feature the topographic potential for rock/iceavalanches to reach a lake were analyzed regarding their susceptibility to slope failure including the factors slope inclination, permafrost occurrence, glacier recession and bedrock lithology. Together with the analysis of the lakes (volume and runout path of potential outburst floods), the hazard analysis of the process chain was completed. As an example, high long-term hazard potentials in the Swiss Alps have, for instance, to be expected in the area of the Great Aletsch glacier. A methodology for the assessment of the damage potential was elaborated and will be presented. In order to estimate the

Atmospheric temperature changes over the 20th century at very high elevations in the European Alps from englacial temperatures

NASA Astrophysics Data System (ADS)

Gilbert, A.; Vincent, C.

2013-05-01

the paucity of observations, a great deal of uncertainty remains concerning temperature changes at very high altitudes over the last century. Englacial temperature measurements performed in boreholes provide a very good indicator of atmospheric temperatures for very high elevations although they are not directly related to air temperatures. Temperature profiles from seven deep boreholes drilled at three different sites between 4240 and 4300 m above sea level in the Mont Blanc area (French Alps) have been analyzed using a heat flow model and a Bayesian inverse modeling approach. Atmospheric temperature changes over the last century were estimated by simultaneous inversion of these temperature profiles. A mean warming rate of 0.14°C/decade between 1900 and 2004 was found. This is similar to the observed regional low altitude trend in the northwestern Alps, suggesting that air temperature trends are not altitude dependent.

Teaching Western Literature to Non-Western Students

ERIC Educational Resources Information Center

Pollock, Eric J.; Chun, Hye Won; Kim, Chung Ah

2008-01-01

This paper explores ways in which Western literature can be taught to Non-western students. This paper demonstrates that non-western values do not have to be overcome but rather Western values can be highlighted and reinforced to deal with literary complexity. Values and ideals such as freedom, self-identity, religion, feminism, and equality are…

Modeling Sustainable Bioenergy Feedstock Production in the Alps

NASA Astrophysics Data System (ADS)

Kraxner, Florian; Leduc, Sylvain; Kindermann, Georg; Fuss, Sabine; Pietsch, Stephan; Lakyda, Ivan; Serrano Leon, Hernan; Shchepashchenko, Dmitry; Shvidenko, Anatoly

2016-04-01

Sustainability of bioenergy is often indicated by the neutrality of emissions at the conversion site while the feedstock production site is assumed to be carbon neutral. Recent research shows that sustainability of bioenergy systems starts with feedstock management. Even if sustainable forest management is applied, different management types can impact ecosystem services substantially. This study examines different sustainable forest management systems together with an optimal planning of green-field bioenergy plants in the Alps. Two models - the biophysical global forest model (G4M) and a techno-economic engineering model for optimizing renewable energy systems (BeWhere) are implemented. G4M is applied in a forward looking manner in order to provide information on the forest under different management scenarios: (1) managing the forest for maximizing the carbon sequestration; or (2) managing the forest for maximizing the harvestable wood amount for bioenergy production. The results from the forest modelling are then picked up by the engineering model BeWhere, which optimizes the bioenergy production in terms of energy demand (power and heat demand by population) and supply (wood harvesting potentials), feedstock harvesting and transport costs, the location and capacity of the bioenergy plant as well as the energy distribution logistics with respect to heat and electricity (e.g. considering existing grids for electricity or district heating etc.). First results highlight the importance of considering ecosystem services under different scenarios and in a geographically explicit manner. While aiming at producing the same amount of bioenergy under both forest management scenarios, it turns out that in scenario (1) a substantially larger area (distributed across the Alps) will need to be used for producing (and harvesting) the necessary amount of feedstock than under scenario (2). This result clearly shows that scenario (2) has to be seen as an "intensification

Possible silica gel in the Olive Fault, Naukluft Nappe Complex, Namibia: A geologic record of dynamic weakening in faults during continental orogenesis

NASA Astrophysics Data System (ADS)

Faber, C.; Rowe, C. D.; Miller, J. A.; Backeberg, N.; Sylvester, F.

2009-12-01

The apparently low frictional strength of faults during earthquake slip is not sufficiently well explained. Dynamic weakening has been observed in recent laboratory experiments at seismic slip rates, even if materials are strong at slow slip rates. Di Toro et al. (2004) performed experiments on crystalline rocks at slip rates of 1m/s and observed frictional strength drops to near zero. Examination of the slip surface revealed an amorophous silica had formed during fast slip and interpreted this as a solidified silica gel. If similar silica gel forms during earthquakes, and solidifies to amorphous silica, it would be expected to slowly crystallize over time. Ujiie et al (2007) reported a microcrystalline silica fault vein from the Shimanto Complex (Japan) which contains colloidal microspheres of silica, consistent with its origin as a silica gel. This vein may have been created during seismic slip, although other explanations are possible. No other natural examples of this potentially important coseismic weakening mechanism have been reported. To investigate whether silica gel actually forms during seismic slip, it will be necessary to discover and fully characterize additional natural examples. The Naukluft Nappe Complex in central Namibia is a foreland thrust stack at the distal southern margin of the Pan-African Damara Orogen (active at ~ 550Ma). A fault vein of microcrystalline silica has been found in an intra-nappe thrust fault . The vein occurs as a mostly continuous, planar, 0.1-1.0cm-thick fault vein within dolomite breccias of the Olive Fault. There are no other veins of silica associated with the fault. The hanging wall and footwall are dolomite and calcareous shales, respectively. The layer is petrographically similar to the microcrystalline silica described by Ujiie et al. (2007). The silica layer is purple-blue to white in color cathodoluminescence, in contrast to the bright turquoise typical of quartz. Although X-ray diffraction spectra show only

From nappe stacking to extensional detachments at the contact between the Carpathians and Dinarides - The Jastrebac Mountains of Central Serbia

NASA Astrophysics Data System (ADS)

Erak, Dalibor; Matenco, Liviu; Toljić, Marinko; Stojadinović, Uroš; Andriessen, Paul A. M.; Willingshofer, Ernst; Ducea, Mihai N.

2017-07-01

Reactivation of inherited nappe contacts is a common process in orogenic areas affected by back-arc extension. The amount of back-arc extension is often variable along the orogenic strike, owing to the evolution of arcuated mountain chains during stages of rapid slab retreat. This evolution creates low rates of extension near rotation poles, where kinematics and interplay with the pre-existing orogenic structure are less understood. The amount of Miocene extension recorded by the Pannonian Basin of Central Europe decreases SE-wards along the inherited Cretaceous - Paleogene contact between the Dinarides and Carpathian Mountains. Our study combines kinematic data obtained from field and micro-structural observations assisted with fission track thermochronological analysis and U-Pb zircon dating to demonstrate a complex poly-phase evolution in the key area of the Jastrebac Mountains of Serbia. A first event of Late Cretaceous exhumation was followed by latest Cretaceous - Eocene thrusting and magmatism related to a continental collision that sutured the accretionary wedge containing contractional trench turbidites. The suture zone was subsequently reactivated and exhumed by a newly observed Miocene extensional detachment that lasted longer in the Jastrebac Mountains when compared with similar structures situated elsewhere in the same structural position. Such extensional zones situated near the pole of extensional-driven rotation favour late stage truncations and migration of extension in a hanging-wall direction, while directions of tectonic transport show significant differences in short distances across the strike of major structures.

Lithospheric structure beneath Central Europe from the POLONAISE'97, CELEBRATION 2000, ALP 2002, and SUDETES 2003 seismic refraction experiments

NASA Astrophysics Data System (ADS)

Guterch, A.; Grad, M.; Keller, G. R.

2005-12-01

Beginning in 1997, Central Europe between the Baltic and Adriatic Seas, has been covered by an unprecedented network of seismic refraction experiments POLONAISE'97, CELEBRATION 2000, ALP 2002, and SUDETES 2003, have only been possible due to a massive international consortium consisted of more than 30 institutions from 16 countries in Europe and North America. The majority of recording instruments was provided by the IRIS/PASSCAL Instrument Center and the University of Texas at El Paso (USA), and several other countries also provided instrumentation. Total length of seismic profiles in all experiments is about 20,000 km. The main results of these experiments are: 1) the delineation of the deep structure of the southwestern margin of the East European Craton (southern Baltica) and its relationship to younger terranes; delineation of the major terranes and crustal blocks in the Trans European Suture Zone; determination of the structural framework of the Pannonian basin; elucidation of the deep structure and evolution of the Western Carpathian Mountains and Eastern Alps; determination of the structural relationships between the structural elements of the Bohemian massif and adjacent features; construction of 3-D models of the lithospheric structure; and evaluation and develop geodynamic models for the tectonic evolution of the region. Experiment Working Groups Members: K. Aric, M. Behm, E. Brueckl, W. Chwatal, H. Grassl, S. Hock, V. Hoeck, F. Kohlbeck, E.-M. Rumpfhuber, Ch. Schmid, R. Schmoller, C. Tomek, Ch. Ullrich, F.Weber (Austria), A.A. Belinsky (Belarus), I. Asudeh, R. Clowes, Z. Hajnal (Canada), F. Sumanova (Croatia), M. Broz , P. Hrubcova, M. Korn, O. Karousova, J. Malek, A. Spicak (Czech Republic), S.L. Jensen, P. Joergensen, H. Thybo (Denmark), K. Komminaho, U. Luosto, T. Tiira, J. Yliniemi (Finland), F. Bleibinhaus, R. Brinkmann, B. Forkmann, H. Gebrande, H. Geissler, A. Hemmann, G. Jentzsch, D. Kracke, A. Schulze, K. Schuster (Germany), T. Bodoky, T

A consistent and uniform research earthquake catalog for the AlpArray region: preliminary results.

NASA Astrophysics Data System (ADS)

Molinari, I.; Bagagli, M.; Kissling, E. H.; Diehl, T.; Clinton, J. F.; Giardini, D.; Wiemer, S.

2017-12-01

The AlpArray initiative (www.alparray.ethz.ch) is a large-scale European collaboration ( 50 institutes involved) to study the entire Alpine orogen at high resolution with a variety of geoscientific methods. AlpArray provides unprecedentedly uniform station coverage for the region with more than 650 broadband seismic stations, 300 of which are temporary. The AlpArray Seismic Network (AASN) is a joint effort of 25 institutes from 10 nations, operates since January 2016 and is expected to continue until the end of 2018. In this study, we establish a uniform earthquake catalogue for the Greater Alpine region during the operation period of the AASN with a aimed completeness of M2.5. The catalog has two main goals: 1) calculation of consistent and precise hypocenter locations 2) provide preliminary but uniform magnitude calculations across the region. The procedure is based on automatic high-quality P- and S-wave pickers, providing consistent phase arrival times in combination with a picking quality assessment. First, we detect all events in the region in 2016/2017 using an STA/LTA based detector. Among the detected events, we select 50 geographically homogeneously distributed events with magnitudes ≥2.5 representative for the entire catalog. We manually pick the selected events to establish a consistent P- and S-phase reference data set, including arrival-time time uncertainties. The reference data, are used to adjust the automatic pickers and to assess their performance. In a first iteration, a simple P-picker algorithm is applied to the entire dataset, providing initial picks for the advanced MannekenPix (MPX) algorithm. In a second iteration, the MPX picker provides consistent and reliable automatic first arrival P picks together with a pick-quality estimate. The derived automatic P picks are then used as initial values for a multi-component S-phase picking algorithm. Subsequently, automatic picks of all well-locatable earthquakes will be considered to calculate

Bedrock topography beneath uppermost part of Aletsch glacier, Central Swiss Alps, revealed from cosmic-ray muon radiography

NASA Astrophysics Data System (ADS)

Nishiyama, Ryuichi; Ariga, Akitaka; Ariga, Tomoko; Käser, Samuel; Lechmann, Alessandro; Mair, David; Scampoli, Paola; Vladymyrov, Mykhailo; Ereditato, Antonio; Schlunegger, Fritz

2017-04-01

In mountainous landscapes such as the Central Alps of Europe, the bedrock topography is one of the most interesting subjects of study since it separates the geological substratum (bedrock) from the overlying unconsolidated units (ice). The geometry of the bedrock topography puts a tight constraint on the erosional mechanism of glaciers. In previous studies, it has been inferred mainly from landscapes where glaciers have disappeared after the termination of the last glacial epoch. However, the number of studies with a focus on the structure beneath active glaciers is limited, because existing exploration methods have limitation in resolution and mobility. The Eiger-μ project proposes a new technology, called muon radiography, to investigate the bedrock geometry beneath active glaciers. The muon radiography is a recent technique that relies on the high penetration power of muon components in natural cosmic rays. Specifically, one can resolve the internal density profile of a gigantic object by measuring the attenuation rate of the intensity of muons after passing through it, as in medical X-ray diagnostic. This technique has been applied to many fields such as volcano monitoring (eg. Ambrosino et al., 2015; Jourde et al., 2016; Nishiyama et al., 2016), detection of seismic faults (eg. Tanaka et al., 2011), inspection inside nuclear reactors, etc. The first feasibility test of the Eiger-μ project has been performed at Jungfrau region, Central Swiss Alps, Switzerland. We installed cosmic-ray detectors consisting of emulsion films at three sites along the Jungfrau railway tunnel facing Aletsch glacier (Jungfraufirn). The detectors stayed 47 days in the tunnel and recorded the tracks of muons which passed through the glacier and bedrock (thickness is about 100 m). Successively the films were chemically developed and scanned at University of Bern with microscopes originally developed for the analysis of physics experiments on neutrino oscillation. The analysis of muon

New insights into the kinematics and seismotectonics of the Adria-Eurasia boundary in the eastern Alps from geodetic and seismic data

NASA Astrophysics Data System (ADS)

Serpelloni, Enrico; Vannucci, Gianfranco; Bennett, Richard A.; Anderlini, Letizia; Cavaliere, Adriano

2015-04-01

In this work we describe a new kinematic and seismotectonic model of the eastern Alps, at the boundary between Italy, Austria, Slovenia and Croatia, obtained from the analysis of geodetic (GPS) and seismological data. We use a dense GPS velocity field, obtained from integration of continuous, semi-continuous and survey-mode networks (~200 GPS stations between longitude 10°E and 17°E and latitude 44.5°N and 47.5°N) and an updated seismic and focal mechanisms catalogue, with uniformly calibrated moment magnitudes from ~1000 B.C.. Improved accuracies and precisions of GPS motion rates have been obtained by filtering displacement time-series for the spatially correlated common mode errors. The eastern Alps mark the boundary between the Adriatic microplate and the Eurasian plate through a wide zone of distributed deformation. Geodetic deformation and seismic release are more localized, and characterized by larger earthquakes, along the southeastern Alps fold-and-thrust belt, which accommodates the large part of the ~N-S Adria-Eurasia convergence, and in Slovenia, where a transition from ~N-S shortening to the eastward escape of the Pannonian Basin units occurs through a complex pattern of crustal deformation. GPS velocities well describe the overall kinematics, with a transition from NNW-ward to NE-ward motion trends (in a Eurasian frame) across Slovenia and Austria, but also show small but significant crustal deformation far from the major blocks boundaries. This may suggest internal continuous deformation or a more complex configuration of interacting tectonic blocks in the eastern Alps. This second hypothesis is taken into account and tested in this work. We use seismic moment release rate maps, active faults databases and inspections of GPS velocities in different local frames to define the geometry of a kinematic block model, constrained by GPS horizontal velocities, in order to estimate blocks rotations and elastic strain at blocks bounding faults. The

Lithospheric structure of the southern French Alps inferred from broadband analysis

NASA Astrophysics Data System (ADS)

Bertrand, E.; Deschamps, A.

2000-11-01

Broadband receiver functions analysis is commonly used to evaluate the fine-scale S-velocity structure of the lithosphere. We analyse teleseismic P-waves and their coda from 30 selected teleseismic events recorded at three seismological stations of to the French TGRS network in the Alpes Maritimes. Receiver functions are computed in the time domain using an SVD matrix inversion method. Dipping Moho and lateral heterogeneities beneath the array are inferred from the amplitude, arrival time and polarity of locally-generated PS phases. We propose that the Moho dips 11° towards 25°±10°N below station CALF, in the outer part of the Alpine belt. At this station, we determine a Moho depth of about 20±2 km; the same depth is suggested below SAOF station also located in the fold-trust belt. Beneath station STET located in the inner part of the Alpine belt, the Moho depth increases to 30 km and dips towards the N-NW. Moreover, 1D-modelling of summed receiver function from STET station constrains a crustal structure significantly different from that observed at stations located in the outer part of the Alps. Indeed, beneath CALF and SAOF stations we need a 2 km thick shallow low velocity layer to fit best the observed receiver functions whereas this layer seems not to be present beneath STET station. Because recent P-coda studies have shown that near-receiver scattering can dominate teleseismic P-wave recordings in tectonically complicated areas, we account for effect of scattering energy in our records from array measurements. As the array aperture is wide relative to the heterogeneity scale length in the area, the array analysis produces only smooth imaging of scatterers beneath the stations.

Strategy for the deployment of a dense broadband temporary array in the Alps: lessons learnt from the CIFALPS experiment

NASA Astrophysics Data System (ADS)

Coralie, Aubert; Anne, Paul; Stefano, Solarino; Sandrine, Roussel; Simone, Salimbeni; Pierre, Zangelmi; Glenn, Cougoulat; Yinshuang, Ai; Weiwei, Xu; Yumei, He; Liang, Zhao

2013-04-01

The CIFALPS (China-Italy-France Alps seismic survey) experiment is a common project of IGGCAS (China), ISTerre (France) and INGV (Italy). It aims at getting new high-resolution passive seismic data on the crustal and upper mantle structure of the southwestern Alps. In this framework, we have installed a temporary broadband seismic array across the southwestern Alps from the Rhône valley (France) to the Po plain (Italy). The main sub-array of CIFALPS is a 350-km long roughly linear profile of 46 stations trending WSW-ENE from Bollène (France) to north of Alessandria (Italy). The average station spacing is 10 km in the outer parts of the belt, and it reduces to 5 km in the internal Alps. Nine additional temporary stations located ~40 km to the north and south of the main profile complement the permanent broadband networks to improve the 3-D constraints on the deep structures. Stations are equipped with Nanometrics Taurus data acquisition systems, and Trillium 120P/A, CMG3-ESP or CMG40T broadband sensors. The array was installed in the summer of 2012 and will be operated at least to April 2013. Because our schedule was tight, we had to achieve site selections in only 3-4 months in spite of strong constraints on site location related to short interstation spacing. Most sites are located in basements of buildings for security reasons and mains power supply. As most sensors are true broadband (90s or 120s), we put much effort on vault design to insure good thermal insulation and low noise at long periods. The vaults also had to be easily and rapidly built and they should be easily and totally removed at the end of the experiment. We used the PQLX software for quality control of our sites and vault design. The performances of our vaults are good for the vertical component with noise levels at 100s period in the range -185 dB (low noise model) to -165 dB. They are less good for horizontal components (noise level close to high noise model at periods > 20s) due to

Read-across of ready biodegradability based on the substrate specificity of N-alkyl polypropylene polyamine-degrading microorganisms.

PubMed

Geerts, R; van Ginkel, C G; Plugge, C M

2017-04-01

The biodegradation of N-alkyl polypropylene polyamines (NAPPs) was studied using pure and mixed cultures to enable read-across of ready biodegradability test results. Two Pseudomonas spp. were isolated from activated sludge with N-oleyl alkyl propylene diamine and N-coco alkyl dipropylene triamine, respectively. Both strains utilized all NAPPs tested as the sole source of carbon, nitrogen and energy for growth. Mineralization of NAPPs was independent of the alkyl chain length and the size of the polyamine moiety. NAPPs degraded in closed bottle tests (CBTs) using both river water and activated sludge. However, ready biodegradability of NAPPs with alkyl chain lengths of 16-18 carbon atoms and polyamine moieties with three and four nitrogen atoms could not be demonstrated. Biodegradation in the CBT was hampered by their limited bioavailability, making assessment of the true ready biodegradability of these highly adsorptive surfactants impossible. All NAPPs are therefore classified as readily biodegradable through read-across. Read-across is justified by the broad substrate specificity of NAPP-degrading microorganisms, their omnipresence and the mineralization of NAPPs.

A new late glacial to early Holocene palaeobotanical and archaeological record in the Eastern Pre-Alps: the Palughetto basin (Cansiglio Plateau, Italy)

NASA Astrophysics Data System (ADS)

Avigliano, Roberto; di Anastasio, Giulio; Improta, Salvatore; Peresani, Marco; Ravazzi, Cesare

2000-12-01

A late glacial to early Holocene lacustrine and peat succession, rich in conifer remains and including some palaeolithic flint artefacts, has been investigated in the Palughetto intermorainic basin (Venetian Pre-Alps). The geomorphological and stratigraphical relationships, 14C dates and pollen analyses allow a reconstruction of the environmental history of the basin and provide significant insights into the reforestation and peopling of the Pre-Alps. The onset of peat accumulation is dated to 14.4-14.1 kyr cal. BP, coinciding with reforestation at middle altitudes that immediately post-dates the immigration of Larix decidua and Picea abies subsp. europaea. Plant macrofossils point to the expansion of spruce about 14.3 kyr cal. BP, so far one of the earliest directly dated in the late glacial period of southern Europe. The previous hypothesis of an early Holocene spruce immigration in the Southern Alps from Slovenia needs reconsideration. Organic sedimentation stopped at the end of the Younger Dryas and was followed by the evolution of hydromorphic soils containing lithic artefacts, anthropic structures and wood charcoal. The typological features of the flint implements refer human occupation of the site to the end of the recent Epigravettian. Charcoals yielded dates either consistent with, or younger than, the archaeological chronology, in the early and middle Holocene.

Impact of droughts on water provision in managed alpine grasslands in two climatically different regions of the Alps

PubMed Central

Ruggenthaler, Romed; Hammerle, Albin; Lavorel, Sandra; Schirpke, Uta; Clement, Jean‐Christophe; Lamarque, Pénélope; Obojes, Nikolaus; Tappeiner, Ulrike

2015-01-01

Abstract This study analyzes the impact of droughts, compared with average climatic conditions, on the supporting ecosystem service water provision in sub‐watersheds in managed alpine grasslands in two climatically different regions of the Alps, Lautaret (French Alps) and Stubai (Austrian Alps). Soil moisture was modelled in the range of 0–0.3 m. At both sites, current patterns showed that the mean seasonal soil moisture was (1) near field capacity for grasslands with low management intensity and (2) below field capacity for grasslands with higher land‐use intensity. Soil moisture was significantly reduced by drought at both sites, with lower reductions at the drier Lautaret site. At the sub‐watershed scale, soil moisture spatial heterogeneity was reduced by drought. Under drought conditions, the evapotranspiration to precipitation ratios at Stubai was slightly higher than those at Lautaret, indicating a dominant ‘water spending’ strategy of plant communities. Regarding catchment water balance, deep seepage was reduced by drought at Stubai more strongly than at Lautaret. Hence, the observed ‘water spending’ strategy at Stubai might have negative consequences for downstream water users. Assessing the water provision service for alpine grasslands provided evidence that, under drought conditions, evapotranspiration was influenced not only by abiotic factors but also by the water‐use strategy of established vegetation. These results highlight the importance of ‘water‐use’ strategies in existing plant communities as predictors of the impacts of drought on water provision services and related ecosystem services at both the field and catchment scale. © 2015 The Authors. Ecohydrology published by John Wiley & Sons, Ltd. PMID:26688705

Structure and evolution of a rocksalt-mudrock-tectonite: The haselgebirge in the Northern Calcareous Alps

PubMed Central

Leitner, Christoph; Neubauer, Franz; Urai, János L.; Schoenherr, Johannes

2011-01-01

The Northern Calcareous Alps are part of the Eastern Alps in Austria and Germany. The Mesozoic units of this fold-and-thrust belt were detached, thrusted and stacked along the evaporitic Haselgebirge Formation. Exposed in salt mines, rocksalt and mudrock form a two component tectonite: The rock type “haselgebirge” consists of 10–70 wt % halite with silt- to gravel- or block-sized components within a halite matrix, and the “kerngebirge” with >70 wt % halite. All rock types studied are fault rocks. By use of a temperature-independent subgrain size piezometer, the paleo-differential stress of halite was calculated at ca. 2.5 MPa in Altaussee and ca. 4.5 MPa in Berchtesgaden. Including data from a grain-size piezometer, temperatures were estimated at ca. 150 ± 20 °C and 110 ± 10 °C. This implies very high strain rates, which are about 10−10–10−9 s−1. During the tectonic movement, the halite deformed, recrystallized, and crystallized as veins in mudrock fractures. We interpret high overpressure of the pore fluid to have significantly contributed to fracturing of the mudrock. PMID:26523077

Photosynthetic temperature adaptation of Pinus cembra within the timberline ecotone of the Central Austrian Alps.

PubMed

Wieser, Gerhard; Oberhuber, Walter; Walder, Lisa; Spieler, Daniela; Gruber, Andreas

2010-04-01

Temperature is suggested to determine the upper limit of tree life. Therefore, future climate warming may be of importance for tree distribution within the European Alps, where low temperatures limit carbon metabolism.We focused on the effects of air and soil temperature on net photosynthesis (P(n)) of Pinus cembra an evergreen climax species of the timberline ecotone of the Central Austrian Alps. Light response and temperature response curves were estimated along an altitudinal gradient ranging from the forest limit up to the krummholz limit in both summer and fall.In general, P(n) was significantly lower in fall as compared to summer. Nevertheless, independent from season mean P(n) values tended to increase with elevation and were positively correlated with root zone temperatures. The specific leaf area by contrast declined with increasing elevation. Furthermore, the temperature optimum of net photosynthesis declined with increasing elevation and was positively correlated with the mean maximum air temperature of the 10 days prior the date of measurement.Thus, our findings appear to reflect a long-term adaptation of the photosynthetic apparatus of Pinus cembra to the general temperature conditions with respect to elevation combined with a short term acclimation to the prevailing temperature regime.

Photosynthetic temperature adaptation of Pinus cembra within the timberline ecotone of the Central Austrian Alps

PubMed Central

Wieser, Gerhard; Oberhuber, Walter; Walder, Lisa; Spieler, Daniela; Gruber, Andreas

2011-01-01

Temperature is suggested to determine the upper limit of tree life. Therefore, future climate warming may be of importance for tree distribution within the European Alps, where low temperatures limit carbon metabolism. We focused on the effects of air and soil temperature on net photosynthesis (Pn) of Pinus cembra an evergreen climax species of the timberline ecotone of the Central Austrian Alps. Light response and temperature response curves were estimated along an altitudinal gradient ranging from the forest limit up to the krummholz limit in both summer and fall. In general, Pn was significantly lower in fall as compared to summer. Nevertheless, independent from season mean Pn values tended to increase with elevation and were positively correlated with root zone temperatures. The specific leaf area by contrast declined with increasing elevation. Furthermore, the temperature optimum of net photosynthesis declined with increasing elevation and was positively correlated with the mean maximum air temperature of the 10 days prior the date of measurement. Thus, our findings appear to reflect a long-term adaptation of the photosynthetic apparatus of Pinus cembra to the general temperature conditions with respect to elevation combined with a short term acclimation to the prevailing temperature regime. PMID:21379394

Observational consistency and future predictions for a 3.5 keV ALP to photon line

DOE Office of Scientific and Technical Information (OSTI.GOV)

Alvarez, Pedro D.; Conlon, Joseph P.; Day, Francesca V.

Motivated by the possibility of explaining the 3.5 keV line through dark matter decaying to axion-like particles that subsequently convert to photons, we study ALP-photon conversion for sightlines passing within 50 pc of the galactic centre. Conversion depends on the galactic centre magnetic field which is highly uncertain. For fields at low or mid-range of observational estimates (10–100 μG), no observable signal is possible. For fields at the high range of observational estimates (a pervasive poloidal mG field over the central 150 pc) it is possible to generate sufficient signal to explain recent observations of a 3.5 keV line inmore » the galactic centre. In this scenario, the galactic centre line signal comes predominantly from the region with  z > 20 pc, reconciling the results from the Chandra and XMM-Newton X-ray telescopes. The dark matter to ALP to photon scenario also naturally predicts the non-observation of the 3.5 keV line in stacked galaxy spectra. We further explore predictions for the line flux in galaxies and suggest a set of galaxies that is optimised for observing the 3.5 keV line in this model.« less

Observational consistency and future predictions for a 3.5 keV ALP to photon line

DOE Office of Scientific and Technical Information (OSTI.GOV)

Alvarez, Pedro D.; Conlon, Joseph P.; Day, Francesca V.

Motivated by the possibility of explaining the 3.5 keV line through dark matter decaying to axion-like particles that subsequently convert to photons, we study ALP-photon conversion for sightlines passing within 50 pc of the galactic centre. Conversion depends on the galactic centre magnetic field which is highly uncertain. For fields at low or mid-range of observational estimates (10–100 μG), no observable signal is possible. For fields at the high range of observational estimates (a pervasive poloidal mG field over the central 150 pc) it is possible to generate sufficient signal to explain recent observations of a 3.5 keV line inmore » the galactic centre. In this scenario, the galactic centre line signal comes predominantly from the region with z>20pc, reconciling the results from the Chandra and XMM-Newton X-ray telescopes. The dark matter to ALP to photon scenario also naturally predicts the non-observation of the 3.5 keV line in stacked galaxy spectra. We further explore predictions for the line flux in galaxies and suggest a set of galaxies that is optimised for observing the 3.5 keV line in this model.« less

Topographic evolution of a continental indenter: The eastern Southern Alps

NASA Astrophysics Data System (ADS)

Robl, Jörg; Heberer, Bianca; Prasicek, Günther; Neubauer, Franz; Hergarten, Stefan

2017-04-01

The topographic evolution of the eastern Southern Alps (ESA) is controlled by the Late Oligocene - Early Miocene indentation of the Adriatic microplate into an overthickened orogenic wedge emplaced on top of the European plate. Rivers follow topographic gradients that evolve during continental collision and in turn incise into bedrock counteracting the formation of topography. In principle, erosional surface processes tend to establish a topographic steady state so that an interpretation of topographic metrics in terms of the latest tectonic history should be straightforward. However, a series of complications impede deciphering the topographic record of the ESA. The Pleistocene glaciations locally excavated alpine valleys and perturbed fluvial drainages. The Late Miocene desiccation of the Mediterranean Sea and the uplift of the northern Molasse Basin led to significant base level changes in the far field of the ESA and the Eastern Alps (EA), respectively. Among this multitude of mechanisms, the processes that dominate the current topographic evolution of the ESA and the ESA-EA drainage divide have not been identified and a number of questions regarding the interaction of crustal deformation, erosion and climate in shaping the present-day topography remain. We demonstrate the expected topographic effects of each mechanism in a 1-dimensional model and compare them with observed channel metrics. Modern uplift rates are largely consistent with long-term exhumation in the ESA and with variations in the normalized steepness index (ksn) indicating a stable uplift and erosion pattern since Miocene times. We find that ksn increases with uplift rate and declines from the indenter tip in the northwest to the foreland basin in the southeast. The number and magnitude of knickpoints and the distortion in longitudinal channel profiles similarly decrease towards the east. Most knickpoints probably evolved during Pleistocene glaciation cycles, but may represent the incrementally

Evaluation of glymphatic system activity with the diffusion MR technique: diffusion tensor image analysis along the perivascular space (DTI-ALPS) in Alzheimer's disease cases.

PubMed

Taoka, Toshiaki; Masutani, Yoshitaka; Kawai, Hisashi; Nakane, Toshiki; Matsuoka, Kiwamu; Yasuno, Fumihiko; Kishimoto, Toshifumi; Naganawa, Shinji

2017-04-01

The activity of the glymphatic system is impaired in animal models of Alzheimer's disease (AD). We evaluated the activity of the human glymphatic system in cases of AD with a diffusion-based technique called diffusion tensor image analysis along the perivascular space (DTI-ALPS). Diffusion tensor images were acquired to calculate diffusivities in the x, y, and z axes of the plane of the lateral ventricle body in 31 patients. We evaluated the diffusivity along the perivascular spaces as well as projection fibers and association fibers separately, to acquire an index for diffusivity along the perivascular space (ALPS-index) and correlated them with the mini mental state examinations (MMSE) score. We found a significant negative correlation between diffusivity along the projection fibers and association fibers. We also observed a significant positive correlation between diffusivity along perivascular spaces shown as ALPS-index and the MMSE score, indicating lower water diffusivity along the perivascular space in relation to AD severity. Activity of the glymphatic system may be evaluated with diffusion images. Lower diffusivity along the perivascular space on DTI-APLS seems to reflect impairment of the glymphatic system. This method may be useful for evaluating the activity of the glymphatic system.

Sedimentary processes and architecture of Upper Cretaceous deep-sea channel deposits: a case from the Skole Nappe, Polish Outer Carpathians

NASA Astrophysics Data System (ADS)

Łapcik, Piotr

2018-02-01

Deep-sea channels are one of the architectonic elements, forming the main conduits for sand and gravel material in the turbidite depositional systems. Deep-sea channel facies are mostly represented by stacking of thick-bedded massive sandstones with abundant coarse-grained material, ripped-up clasts, amalgamation and large scale erosional structures. The Manasterz Quarry of the Ropianka Formation (Upper Cretaceous, Skole Nappe, Carpathians) contains a succession of at least 31 m of thick-bedded high-density turbidites alternated with clast-rich sandy debrites, which are interpreted as axial deposits of a deep-sea channel. The section studied includes 5 or 6 storeys with debrite basal lag deposits covered by amalgamated turbidite fills. The thickness of particular storeys varies from 2.5 to 13 m. Vertical stacking of similar facies through the whole thickness of the section suggest a hierarchically higher channel-fill or a channel complex set, with an aggradation rate higher than its lateral migration. Such channel axis facies cannot aggrade without simultaneous aggradation of levee confinement, which was distinguished in an associated section located to the NW from the Manasterz Quarry. Lateral offset of channel axis facies into channel margin or channel levee facies is estimated at less than 800 m. The Manasterz Quarry section represents mostly the filling and amalgamation stage of channel formation. The described channel architectural elements of the Ropianka Formation are located within the so-called Łańcut Channel Zone, which was previously thought to be Oligocene but may have been present already in the Late Cretaceous.

Developing a visual moraine classification scheme to support investigations into the Holocene glacier chronology of the Southern Alps, New Zealand

NASA Astrophysics Data System (ADS)

Kaufung, Eva; Winkler, Stefan

2014-05-01

The Southern Alps of New Zealand have provided one of only a few suitable study sites for investigating Holocene glacier chronologies in the mid-latitudinal Southern Hemisphere. Although a considerable number of studies have been conducted during the past few decades, these generally focus on a very limited number of glacier forelands. Additionally, those glaciers studied have often been selected because of their accessibility rather than their representativeness for the whole region. A common drawback of many regional studies is the lack of attention to glacial geomorphology and the mode of moraine formation with the dating of such landforms in chronological context. With the Southern Alps characterized by very dynamic geomorphological process-systems and a high seismic activity, this seems unfortunate as it causes a relatively high potential "geomorphological uncertainty" with any published glacier chronology and its subsequent palaeoclimatological interpretation. Future investigations into the Holocene glacier chronology in the Southern Alps need to address those existing shortcomings and, consequently, should achieve a representative spatial distribution of study sites in order to overcome the current strong data bias towards few, albeit relatively well-studied glacier forelands. The specific regional geomorphological environment of the Southern Alps requires, furthermore, a thorough assessment of any moraine selected for the subsequent dating in consideration of its "reliability" if it is considered as evidence of specific former glacier variations. With more than 3000 potential glacier forelands in the entire mountain range, careful selection of future targets for successful chronological field work is essential. We present the preliminary results of an ongoing, time-efficient study to apply different remote sensing sources (aerial photography, Google Earth, satellite images) to evaluate the potential of certain glacier forelands for detailed ground

A field-guide to the geology of Kythnos, Western Cyclades, Greece

NASA Astrophysics Data System (ADS)

Rice, A. Hugh N.; Grasemann, Bernhard

2017-04-01

This poster advertises a new field-guide to the island of Kythnos, within the Western Cyclades: kmz files of the outcrop descriptions etc. can be downloaded from the QR-code. Kythnos comprises schists and marbles of the Cycladic Blueschist Nappe in the footwall of the Miocene West Cycladic Detachment System, with a small outcrop of the hanging wall (Pelagonian Zone) in the southwest of the island. Stretching lineations change from ENE-WSW in the north to NNE-SSW in the south, reflecting a reorientation of Eocene exhumation strains towards the West Cycladic Detachment System extension direction; overall, finite strains increase towards the south and west. The guide is divided into six day-long excursions, with a total of 63 stops; for several excursions more outcrops than can be reasonably visited in one day are given, allowing some choice in the outcrops seen. However, the island is so small (20 x 11 km) that almost any selection of outcrops can be included in a day, since most lie beside or close to a road and require little walking. Descriptions of six outcrops as seen from the local ferries are also given. The guide documents both the dominant and unusual lithologies on the island as well as the major structural features of the island. In particular; deformation associated with the emplacement of the Pelagonian Zone hanging wall along the West Cycladic Detachment System; the development of an intermediate-scale low-angled detachment linking higher-angled Riedel fractures (Ag. Ioannis Detachment); the pervasive thinning and down-faulting of the rocks to the west, with contemporary ductile deformation in blue-grey marble and brittle deformation in quartz-rich layers within the blue-grey marble; and the possibility that a very large-scale recumbent isoclinal fold forms the island.

Alp7/TACC recruits kinesin-8–PP1 to the Ndc80 kinetochore protein for timely mitotic progression and chromosome movement

PubMed Central

Tang, Ngang Heok; Toda, Takashi

2015-01-01

ABSTRACT Upon establishment of proper kinetochore–microtubule attachment, the spindle assembly checkpoint (SAC) must be silenced to allow onset of anaphase, which is when sister chromatids segregate equally to two daughter cells. However, how proper kinetochore–microtubule attachment leads to timely anaphase onset remains elusive. Furthermore, the molecular mechanisms of chromosome movement during anaphase A remain unclear. In this study, we show that the fission yeast Alp7/TACC protein recruits a protein complex consisting of the kinesin-8 (Klp5–Klp6) and protein phosphatase 1 (PP1) to the kinetochore upon kinetochore–microtubule attachment. Accumulation of this complex at the kinetochore, on the one hand, facilitates SAC inactivation through PP1, and, on the other hand, accelerates polewards chromosome movement driven by the Klp5–Klp6 motor. We identified an alp7 mutant that had specific defects in binding to the Klp5–Klp6–PP1 complex but with normal localisation to the microtubule and kinetochore. Consistent with our proposition, this mutant shows delayed anaphase onset and decelerated chromosome movement during anaphase A. We propose that the recruitment of kinesin-8–PP1 to the kinetochore through Alp7/TACC interaction plays a crucial role in regulation of timely mitotic progression and chromosome movement during anaphase A. PMID:25472718

Global and local-scale variation in bacterial community structure of snow from the Swiss and Australian Alps.

PubMed

Wunderlin, Tina; Ferrari, Belinda; Power, Michelle

2016-09-01

Seasonally, snow environments cover up to 50% of the land's surface, yet the microbial diversity and ecosystem functioning within snow, particularly from alpine regions are not well described. This study explores the bacterial diversity in snow using next-generation sequencing technology. Our data expand the global inventory of snow microbiomes by focusing on two understudied regions, the Swiss Alps and the Australian Alps. A total biomass similar to cell numbers in polar snow was detected, with 5.2 to 10.5 × 10(3) cells mL(-1) of snow. We found that microbial community structure of surface snow varied by country and site and along the altitudinal range (alpine and sub-alpine). The bacterial communities present were diverse, spanning 25 distinct phyla, but the six phyla Proteobacteria (Alpha- and Betaproteobacteria), Acidobacteria, Actinobacteria, Bacteroidetes, Cyanobacteria and Firmicutes, accounted for 72%-98% of the total relative abundance. Taxa such as Acidobacteriaceae and Methylocystaceae, associated with cold soils, may be part of the atmospherically sourced snow community, while families like Sphingomonadaceae were detected in every snow sample and are likely part of the common snow biome. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Natural Hazard Management from a Coevolutionary Perspective: Exposure and Policy Response in the European Alps.

PubMed

Fuchs, Sven; Röthlisberger, Veronika; Thaler, Thomas; Zischg, Andreas; Keiler, Margreth

2017-03-04

A coevolutionary perspective is adopted to understand the dynamics of exposure to mountain hazards in the European Alps. A spatially explicit, object-based temporal assessment of elements at risk to mountain hazards (river floods, torrential floods, and debris flows) in Austria and Switzerland is presented for the period from 1919 to 2012. The assessment is based on two different data sets: (1) hazard information adhering to legally binding land use planning restrictions and (2) information on building types combined from different national-level spatial data. We discuss these transdisciplinary dynamics and focus on economic, social, and institutional interdependencies and interactions between human and physical systems. Exposure changes in response to multiple drivers, including population growth and land use conflicts. The results show that whereas some regional assets are associated with a strong increase in exposure to hazards, others are characterized by a below-average level of exposure. The spatiotemporal results indicate relatively stable hot spots in the European Alps. These results coincide with the topography of the countries and with the respective range of economic activities and political settings. Furthermore, the differences between management approaches as a result of multiple institutional settings are discussed. A coevolutionary framework widens the explanatory power of multiple drivers to changes in exposure and risk and supports a shift from structural, security-based policies toward an integrated, risk-based natural hazard management system.

Natural Hazard Management from a Coevolutionary Perspective: Exposure and Policy Response in the European Alps

PubMed Central

Fuchs, Sven; Röthlisberger, Veronika; Thaler, Thomas; Zischg, Andreas; Keiler, Margreth

2017-01-01

A coevolutionary perspective is adopted to understand the dynamics of exposure to mountain hazards in the European Alps. A spatially explicit, object-based temporal assessment of elements at risk to mountain hazards (river floods, torrential floods, and debris flows) in Austria and Switzerland is presented for the period from 1919 to 2012. The assessment is based on two different data sets: (1) hazard information adhering to legally binding land use planning restrictions and (2) information on building types combined from different national-level spatial data. We discuss these transdisciplinary dynamics and focus on economic, social, and institutional interdependencies and interactions between human and physical systems. Exposure changes in response to multiple drivers, including population growth and land use conflicts. The results show that whereas some regional assets are associated with a strong increase in exposure to hazards, others are characterized by a below-average level of exposure. The spatiotemporal results indicate relatively stable hot spots in the European Alps. These results coincide with the topography of the countries and with the respective range of economic activities and political settings. Furthermore, the differences between management approaches as a result of multiple institutional settings are discussed. A coevolutionary framework widens the explanatory power of multiple drivers to changes in exposure and risk and supports a shift from structural, security-based policies toward an integrated, risk-based natural hazard management system. PMID:28267154

Flood hazard management from a coevolutionary perspective: exposure and policy response in the European Alps

NASA Astrophysics Data System (ADS)

Fuchs, Sven; Röthlisberger, Veronika; Thaler, Thomas; Zischg, Andreas; Keiler, Margreth

2017-04-01

A coevolutionary perspective is adopted to understand the dynamics of exposure to hydrological hazards in the European Alps. A spatially explicit, object-based temporal assessment of elements at risk to flood hazards (river floods, torrential floods and debris flows) in Austria and Switzerland is presented for the 1919-2012 period. The assessment is based on two different datasets, (a) hazard information adhering to legally binding land use planning restrictions and (b) information on building types combined from different national level spatial data. We discuss these transdisciplinary dynamics and focus on economic, social and institutional interdependencies and interactions between human and physical systems. Exposure changes in the response to multiple drivers, including population growth and land use conflicts. The results show that while some regional assets are associated with a strong increase in exposure to hazards, others are characterized by a below-average level of exposure. The spatiotemporal results indicate relatively stable hot spots in the European Alps. These results coincide with the topography of the countries and with the respective range of economic activities and political settings. Furthermore, the differences between management approaches as a result of multiple institutional settings are discussed. A coevolutionary framework widens the explanatory power of multiple drivers to changes in exposure and risk, and supports a shift from structural, security-based policies towards an integrated, risk-based natural hazard management system.

Historical glacier outlines from digitized topographic maps of the Swiss Alps

NASA Astrophysics Data System (ADS)

Freudiger, Daphné; Mennekes, David; Seibert, Jan; Weiler, Markus

2018-04-01

Since the end of the Little Ice Age around 1850, the total glacier area of the central European Alps has considerably decreased. In order to understand the changes in glacier coverage at various scales and to model past and future streamflow accurately, long-term and large-scale datasets of glacier outlines are needed. To fill the gap between the morphologically reconstructed glacier outlines from the moraine extent corresponding to the time period around 1850 and the first complete dataset of glacier areas in the Swiss Alps from aerial photographs in 1973, glacier areas from 80 sheets of a historical topographic map (the Siegfried map) were manually digitized for the publication years 1878-1918 (further called first period, with most sheets being published around 1900) and 1917-1944 (further called second period, with most sheets being published around 1935). The accuracy of the digitized glacier areas was then assessed through a two-step validation process: the data were (1) visually and (2) quantitatively compared to glacier area datasets of the years 1850, 1973, 2003, and 2010, which were derived from different sources, at the large scale, basin scale, and locally. The validation showed that at least 70 % of the digitized glaciers were comparable to the outlines from the other datasets and were therefore plausible. Furthermore, the inaccuracy of the manual digitization was found to be less than 5 %. The presented datasets of glacier outlines for the first and second periods are a valuable source of information for long-term glacier mass balance or hydrological modelling in glacierized basins. The uncertainty of the historical topographic maps should be considered during the interpretation of the results. The datasets can be downloaded from the FreiDok plus data repository (https://freidok.uni-freiburg.de/data/15008,

Spatial and temporal patterns of wildfires in the Northern Alps

NASA Astrophysics Data System (ADS)

Heel, Michael; Sass, Oliver; Friedmann, Arne; Wetzel, Karl-Friedrich

2010-05-01

Wildfires in the northern Alps are rare compared to e.g. the Mediterranean region. However, fires occurring on the dry, south-exposed slopes of the inner-alpine valleys can constitute a significant disturbance of the ecosystems in the sub-alpine belt. We reconstructed the younger regional wildfire history (last few centuries) of a part of the the Northern Limestone Alps using chronicles, forestry and fire brigade records as well as historical pictures (postcards, aerial photos etc.), local names and interviews with local people. The long-term fire frequency was investigated using mire drillings, charcoal in soils and dendrochronology. In the surrounding of the Karwendel, Wetterstein and Mieminger Mountains we have identified c. 400 forest fires to date. The earliest detected fire dates to more than 2900 years; the largest one (in 1705) affected an area of several thousand hectares. Approximately 90% of the fires are man-made (negligence, arson, railway) which explains the concentration on the south-exposed slopes of the densely populated Inn valley. Most of the larger fires take place in the altitudinal belt between 1400 and 1900 m a.s.l.; apart from very few exceptions, they are restricted to southerly orientations. Locally, mean recurrence intervals of 200-300 years occur which is similar to e.g. boreal forests in Canada. We observed a strong seasonality with 40% of the fires occurring in spring and 30% in summer. There is a weak correlation with the weather conditions in the one or two weeks before the fire with dry periods promoting wildfire ignition and burnt area size; however, there are many exceptions from the rule. The 1940ies stands out for more than twice as much fires than in all other decades which is both due to climatic and anthropogenic causes. Today, there is an apparent trend towards more frequent and smaller fires. The frequency is biased by the multitude of available documentation today (e.g. websites of fire brigades), while the decreasing size

Potential cretaceous play in the Rharb basin of northern Morocco

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jobidon, G.P.

1993-09-01

The autochthonous Cretaceous in the Rharb basin of northern Morocco is located underneath a cover of neogene sediments and of the Prerif nappe olistostrome, which was emplaced during the Tortonian 7 m.y. The presence of infranappe Cretaceous sediments is documented in a few onshore wells in the Rharb basin and in the adjacent Prerif Rides area, as well as in the Rif Mountains. Their presence in the deeper portion of the Rharb basin is difficult to detail because of poor seismic resolution data beneath dispersive prerif nappe. A recent study of offshore seismic data acquired by PCIAC in 1987 indicatesmore » that the infranappe interval can be more than 1500 m thick in some of the offshore Kenitra area. These sediments have seismic signatures that would correspond to Middle Cretaceous transgressions, culminating with a Turonian highstand. Their deposition systems were located on the northern and western flanks of the Meseta and were followed by a hiatus lasting until the Miocene. Regional studies of gravity and magnetic data provide and additional understanding of the Rif province, its evolution, and the possible presence of autochthonous Cretaceous sediments below the prerif nappe cover. The infranappe of Rharb basin has a good potential to develop into a major hydrocarbon play with the presence of middle Cretaceous reservoir rocks, Turonian-Cenomanian black shale source rocks, as well as the timely combination of trap formation, source rock maturation, and hydrocarbon migration.« less

Permian age from radiolarites of the Hawasina nappes, Oman Mountains

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wever, P.D.; Grissac C.B.; Bechennec, F.

1988-10-01

The Hawasina napper of the Oman Mountains yielded Permian radiolarians from cherts stratigraphically overlying a thick volcanic basement (Al Jil Formation) at the base of the Hamrat Duru Group. This fauna represents the first Permian radiolarians and radiolarites in the central and western Tethyan realm. A Permain age for pelagic sequences within the Hawasina Complex of Oman has major significance for regional paleogeographic reconstruction. A clear differentiation between platform (reefal sediments) and basin (radiolarites) from the base of the Late Permian (255 Ma) is implied. It suggests a flexure of the platform during Permian time; the present data implies thatmore » a zone of rifting was already developed adjacent to the northeast Gondwana platform margin during the Late Permian. The Hamrat Duru Basin corresponds to an opening intracontinental rift area (sphenochasm) between Arabia and northeast Gondwana, a reentrant of the paleo-Tethys.« less

Holocene temperature variations at a high-altitude site in the Eastern Alps: a chironomid record from Schwarzsee ob Sölden, Austria

PubMed Central

Ilyashuk, Elena A.; Koinig, Karin A.; Heiri, Oliver; Ilyashuk, Boris P.; Psenner, Roland

2011-01-01

Few well-dated, quantitative Holocene temperature reconstructions exist from high-altitude sites in the Central Eastern Alps. Here, we present a chironomid-based quantitative reconstruction of mean July air temperatures (TJuly) throughout the Holocene for a remote high-mountain lake, Schwarzsee ob Sölden, situated above the treeline at 2796 m a.s.l. in the Austrian Alps. Applying a chironomid-temperature inference model developed from lakes of the Alpine region to a high-resolution chironomid record from the lake provides evidence for early Holocene (ca 10000–8600 cal yr BP) TJuly of up to 8.5 °C, i.e. >4 °C above the modern (1977–2006) mean July temperature. The reconstruction reveals the so-called ‘8.2-ka cold event’ centered at ca 8250–8000 cal yr BP with temperatures ca 3 °C below the early-Holocene thermal maximum. Rather warm (ca 6 °C) and productive conditions prevailed during ca 7900–4500 cal yr BP. The chironomid record suggests a climate transition between ca 5200 and 4500 cal yr BP to cooler TJuly. A distinct cooling trend is evident from ca 4500 until ca 2500 cal yr BP. Thereafter, the study site experienced its coldest conditions (around 4 °C or less) throughout the rest of the Holocene, with the exception of the warming trend during the late 20th century. Beside other factors, the Northern Hemisphere summer insolation seems to be the major driving force for the long-term trends in TJuly at high altitudes in the Eastern Alps. Due to the extreme location of the lake and the limited temperature range represented by the applied calibration data set, the chironomid-based temperature reconstruction fails to track phases of the late-Holocene climatic history with TJuly cooler than 4 °C. Further chironomid-based palaeoclimate model and down-core studies are required to address this problem, provide more realistic TJuly estimates from undisturbed high-altitude lakes in the Alps, and extract a reliable regional

Frozen Nature - A high-alpine ice core record reveals fire and vegetation dynamics in Western Europe over the past millennium

NASA Astrophysics Data System (ADS)

Brügger, S.; Gobet, E.; Sigl, M.; Osmont, D.; Schwikowski, M.; Tinner, W.

2017-12-01

Wild fires are an ecological disturbance agent across ecosystems, driving vegetation dynamics and resulting in disruption of habitats (Moritz et al. 2014).We analyze pollen and spores as proxies for vegetation composition, structure and agricultural activity, microscopic charcoal as a proxy for fire activity, and spheroidal carbonaceous particles (SCPs or soots) as a proxy for fossil fuel combustion which preserve in ice cores over millennia (Eichler et al. 2011).Our high-alpine ice core (4452 m a.s.l.) from Colle Gnifetti, Swiss Alps is located in the center of Western Europe, thus allowing to assess vegetation and societal responses to climatic change and wildfire disturbance on a subcontinental scale. The record covers the last millennium with an excellent chronological control (Jenk et al. 2009, Sigl et al. 2009), particularly over the most recent 200 years - the period that experienced important climatic changes and an increasing globalization of economy.The Colle Gnifetti record reflects large scale impacts such as extreme weather, societal innovations, agricultural crises and pollution of the industrial period in Western Europe. Pollution tracers occur in the record as early as 1750 AD and coincide with the shift to large-scale maize production in Northern Italy and with increased fire activity. Our multiproxy record may allow desentagling the role of climate and humans for vegetation composition and biomass burning. The attribution of causes may significantly advance our understanding of future vegetation and fire dynamics under global change conditions. To our knowledge we present the first long-term high-resolution palynological record of a high elevation ice core in Europe.REFERENCESEichler et al. (2011): An ice-core based history of Siberian forest fires since AD 1250. Quaternary Science Reviews, 30(9), 1027-1034.Jenk et al. (2009): A novel radiocarbon dating technique applied to an ice core from the Alps indicating late Pleistocene ages. Journal of

Postglacial recolonization in a cold climate specialist in western Europe: patterns of genetic diversity in the adder (Vipera berus) support the central-marginal hypothesis.

PubMed

Ursenbacher, Sylvain; Guillon, Michaël; Cubizolle, Hervé; Dupoué, Andréaz; Blouin-Demers, Gabriel; Lourdais, Olivier

2015-07-01

Understanding the impact of postglacial recolonization on genetic diversity is essential in explaining current patterns of genetic variation. The central-marginal hypothesis (CMH) predicts a reduction in genetic diversity from the core of the distribution to peripheral populations, as well as reduced connectivity between peripheral populations. While the CMH has received considerable empirical support, its broad applicability is still debated and alternative hypotheses predict different spatial patterns of genetic diversity. Using microsatellite markers, we analysed the genetic diversity of the adder (Vipera berus) in western Europe to reconstruct postglacial recolonization. Approximate Bayesian Computation (ABC) analyses suggested a postglacial recolonization from two routes: a western route from the Atlantic Coast up to Belgium and a central route from the Massif Central to the Alps. This cold-adapted species likely used two isolated glacial refugia in southern France, in permafrost-free areas during the last glacial maximum. Adder populations further from putative glacial refugia had lower genetic diversity and reduced connectivity; therefore, our results support the predictions of the CMH. Our study also illustrates the utility of highly variable nuclear markers, such as microsatellites, and ABC to test competing recolonization hypotheses. © 2015 John Wiley & Sons Ltd.

Elastic anisotropy and borehole stress estimation in the Seve Nappe Complex from the COSC-1 well, Åre, Sweden.

NASA Astrophysics Data System (ADS)

Wenning, Quinn; Almquist, Bjarne; Ask, Maria; Schmitt, Douglas R.; Zappone, Alba

2015-04-01

The Caledonian orogeny, preserved in Scandinavia and Greenland, began with the closure of the Iapetus Ocean and culminated in the collision of Baltica and Laurentia cratons during the middle Paleozoic. The COSC scientific drilling project aims at understanding the crustal structure and composition of the Scandinavian Caledonides. The first well of the dual phase drilling program, completed in Summer of 2014, drilled through ~2.5 km of the Seve Nappe Complex near the town of Åre, Sweden. Newly acquired drill core and borehole logs provide fresh core material for physical rock property measurements and in-situ stress determination. This contribution presents preliminary data on compressional and shear wave ultrasonic velocities (Vp, Vs) determined from laboratory measurements on drill cores, together with in-situ stress orientation analysis using image logs from the first borehole of the Collisional Orogeny in the Scandinavian Caledonides project (COSC-1). An hydrostatically oil pressurized apparatus is used to test the ultrasonic Vp and Vs on three orthogonally cut samples of amphibolite, calcium bearing and felsic gneiss, meta-gabbro, and mylonitic schist from drill core. We measure directional anisotropy variability for each lithology using one sample cut perpendicular to the foliation and two additional plugs cut parallel to the foliation with one parallel to the lineation and the other perpendicular. Measurements are performed using the pulse transmission technique on samples subjected to hydrostatic pressure from 1-350 MPa at dry conditions. We present preliminary results relating Vp and Vs anisotropy to geologic units and degree of deformation. Additionally, we use acoustic borehole televiewer logs to estimate the horizontal stress orientation making use of well developed techniques for observed borehole breakouts (compressive failure) and drilling induced fractures (tensile failure). Preliminary observations show that very few drilling-induced tensile

Geodiversity and Geoheritage of the Sesia-Val Grande Unesco Geopark (NW-Italy)

NASA Astrophysics Data System (ADS)

Giardino, Marco; Palomba, Mauro; Selvaggio, Ilaria; Ghiraldi, Luca; Giordano, Enrico

2015-04-01

The Sesia-Valgrande Geopark has been founded in September 2013. It is located in the northern sector of Piemonte region covering an area of almost 214000 hectares. In the northern side the Geopark includes the entire territory of the Val Grande National Park, a small portion of the Ossola Valley and the Cannobina valley, while in the south covers most of the mountain range of the Sesia Valley and portions of neighbouring territories such as Valsessera, Prealpi Biellesi, Val Strona and Alte Colline Novaresi. The present morphology of the whole area is characterized by landforms shaped by different geomorphological processes: glacial, hydrological, gravitational and in the south parts also by karstic phenomena. From the geological point of view the Sesia-Val Grande Geopark "rides" the Canavese segment of the Insubric Line, a major tectonic boundary of the Alps. North- and Westward of the Insubric Line, the Austro-Alpine domain consists of piles of nappes, which were assembled and affected by a polymetamorphic event during the Alpine orogeny. South- and Eastward of the Insubric Line, South-Alpine Rock units were not affected by this metamorphic event: they preserve an older history, despite experiencing substantial Alpine tectonic deformation. These are the original rocks of the northern margin of the Adriatic plate, an exceptional record of metamorphic and igneous events preserved with a virtually intact section of the pre-Alpine crust. Beyond geological heritage this territory is one of the most appealing natural environments of the Western Alps, including several different protected areas, important Walser settlement (13th century) and Palaeolithic human traces in the Monte Fenera caves, religious and artistic attraction dominated by the Ghiffa and Varallo Sacred Mount and eventually sport activities such as rafting, hiking, mountaineering and climbing. In order to promote cultural and geological heritage of the area, several scientific institution have been

Holocene vegetation and fire dynamics at Crveni Potok, a small mire in the Dinaric Alps (Tara National Park, Serbia)

NASA Astrophysics Data System (ADS)

Finsinger, Walter; Morales-Molino, Cesar; Gałka, Mariusz; Valsecchi, Verushka; Bojovic, Srdjan; Tinner, Willy

2017-07-01

We analysed sediments from Crveni Potok (Tara Mountains, Serbia), a key site in the Dinaric Alps because it is located within the restricted distribution range of the endemic conifer Picea omorika (Serbian spruce), and thereby bears a unique potential in revealing its Holocene history. We used a set of proxies (pollen, plant-macrofossils, charcoal) to reconstruct the long-term vegetation and fire histories at different spatial scales. The comprehensive snapshot provided by the reconstructions fill an important gap of European long-term vegetation and fire histories in the overall data-coverage poor region of the Dinaric Alps. The reconstructions unfolded an unusual late-Holocene persistence of high forest cover that contrasts with the large majority of European landscape-scale forest-cover records, which show massive anthropogenic openings in the past two millennia. We also found evidence for good post-fire recovery of the currently threatened endemic P. omorika populations. This leads us to suggest that prescribed-burning programmes may be beneficial to reduce the vulnerability of the species, and for ecological restoration and conservation purposes of the declining and endangered populations.

Seismically-triggered soft-sediment deformation structures close to a major strike-slip fault system in the Eastern Alps (Hirlatz cave, Austria)

NASA Astrophysics Data System (ADS)

Salomon, Martina Lan; Grasemann, Bernhard; Plan, Lukas; Gier, Susanne; Schöpfer, Martin P. J.

2018-05-01

We investigate episodic soft-sediment deformation structures cross-cut by normal faults preserved in unlithified finely laminated calcite rich sediments in the Hirlatz cave in the Northern Calcareous Alps (Austria). These sediments comprise varve-like alternations of brighter carbonate/quartz rich layers, and darker clay mineral rich layers. The deformed sediments contain abundant millimeter to centimeter-scale soft-sediment structures (load casts, ball-and-pillow structures), sheet slumps (thrust faults and folds), erosive channels filled with slides and chaotic slumps. After deposition and soft-sediment deformation normal faults developed within the entire sedimentary succession, an event that probably correlates with an offset of c. 10 cm of the passage wall above the outcrop. Our major conclusions are: (i) The sediments have a glacial origin and were deposited in the Hirlatz cave under phreatic fluvio-lacustrine conditions. The deposition and the soft-sediment deformation occurred most likely during the last glaciation (i.e. around 25 ka ago); (ii) The liquefaction and formation of the soft-sediment structures in water-saturated stratified layers was triggered by episodic seismic events; (iii) The internally deformed sediments were later displaced by normal faults; (iv) A possible source for the seismic events is the active sinistral Salzach-Ennstal-Mariazeller-Puchberger (SEMP) strike-slip fault which is located about 10 km south of the outcrop and plays a major role in accommodating the extrusion of the Eastern Alps towards the Pannonian Basin. To our knowledge, the described structures are the first report of liquefaction and seismically induced soft-sediment deformations in Quaternary sediments in the Eastern Alps.

Time constraints for post-LGM landscape response to deglaciation in Val Viola, Central Italian Alps

NASA Astrophysics Data System (ADS)

Scotti, Riccardo; Brardinoni, Francesco; Crosta, Giovanni Battista; Cola, Giuseppe; Mair, Volkmar

2017-12-01

Across the northern European Alps, a long tradition of Quaternary studies has constrained post-LGM (Last Glacial Maximum) landscape history. The same picture remains largely unknown for the southern portion of the orogen. In this work, starting from existing 10Be exposure dating of three boulders in Val Viola, Central Italian Alps, we present the first detailed, post-LGM reconstruction of landscape (i.e., glacial, periglacial and paraglacial) response south of the Alpine divide. We pursue this task through Schmidt-hammer exposure-age dating (SHD) at 34 sites including moraines, rock glaciers, protalus ramparts, rock avalanche deposits and talus cones. In addition, based on the mapping of preserved moraines and on the numerical SHD ages, we reconstruct the glacier extent of four different stadials, including Egesen I (13.1 ± 1.1 ka), Egesen II (12.3 ± 0.6 ka), Kartell (11.0 ± 1.4 ka) and Kromer (9.7 ± 1.4 ka), whose chronologies agree with available counterparts from north of the Alpine divide. Results show that Equilibrium Line Altitude depressions (ΔELAs) associated to Younger Dryas and Early Holocene stadials are smaller than documented at most available sites in the northern Alps. These findings not only support the hypothesis of a dominant north westerly atmospheric circulation during the Younger Dryas, but also suggest that this pattern could have lasted until the Early Holocene. SHD ages on rock glaciers and protalus ramparts indicate that favourable conditions to periglacial landform development occurred during the Younger Dryas (12.7 ± 1.1 ka), on the valley slopes above the glacier, as well as in newly de-glaciated areas, during the Early Holocene (10.7 ± 1.3 and 8.8 ± 1.8 ka). The currently active rock glacier started to develop before 3.7 ± 0.8 ka and can be associated to the Löbben oscillation. Four of the five rock avalanches dated in Val Viola cluster within the Early Holocene, in correspondence of an atmospheric warming phase. By contrast

From the valley floor to the peaks: Stratigraphy and landscape evolution of the Alpine Lateglacial in the Kitzbühel Alps (Tyrol, Austria)

NASA Astrophysics Data System (ADS)

Dippenaar, Elijah; Reitner, Jürgen

2017-04-01

Our understanding of Alpine landscape evolution and more specifically, chronology of glacier activity during the Alpine Lateglacial (ALG; c. 19 - 11.7 ka) i.e. the timespan between the Würmian Pleniglacial (= Alpine Last Glacial Maximum; AlpLGM) and the beginning of the Holocene, is based on the evidence of only few areas in the Alps. In order to get a better understanding of glaciation and palaeoclimate during this phase, N-S and E-W transects are needed. The Kitzbühel Alps, which are currently not glaciated, span an area of 1700km2 and have peaks that reach c. 2400m a.s.l. They lie at the center of the Eastern Alps on the northern rim, which is more humid than the relatively dry central parts. A modern geological investigation of the ALG record is missing in the Kitzbühel Alps. In order to overcome this gap of knowledge and to gain a more complete understanding of the ALG landscape development, a pioneering study has been performed in the area of Langer Grund Valley, a tributary valley of the Kelchsau Valley. This was done through detailed field mapping, thereby describing the shape and sediment composition of Quaternary morphological features, such as moraines, landslides and rock glacier deposits. Sedimentary evidence of one short glacial advance and two glacial stadials were identified. In chronological order they were named the: Frommbach advance, the Arnbach (glacier) halt and the Küharn halt. Where possible, palaeoglaciers were constructed using ArcGIS. With the palaeoglaciers, equlibrium line altitudes (ELA) were calculated and compared to ELA values of known glacial stadials in an attempt to correlate the relative local stratigraphy to the Lateglacial stratigraphy. Four methods to calculate ELAs were used; Maximum Elevation of Lateral Moraines (MELM), Toe to Headwall Altitude Ratio (THAR), Area x Altitude (AA) and Accumulation Area Ratio (AAR). Furthermore, the glacial sedimentary sequence of the study area was compared to that of the Gschnitz Valley

Glacier retreat and associated sediment dynamics in proglacial areas: a case study from the Silvretta Alps, Austria

NASA Astrophysics Data System (ADS)

Felbauer, Lucia; Pöppl, Ronald

2016-04-01

Global warming results in an ongoing retreat of glaciers in the Alps, leaving behind large amounts of easily erodible sediments. In addition, the debuttressing of rock-walls and the decay of permafrost in the high mountain regions facilitates mass movements of potential disastrous consequences, such as rock falls, landslides and debris flows. Therefore, it is highly important to quantify the amount of sediments that are supplied from the different compartments and to investigate how glacial retreat influences sediment dynamics in proglacial areas. In the presented work glacier retreat and associated sediment dynamics were investigated in the Kromer valley (Silvretta Alps, Austria) by analyzing remote sensing data. Glacial retreat from the period of 1950 to 2012 was documented by interpreting aerial photographs. By digitizing the different stages of the glaciers for six time frames, changes in glacier area and length were mapped and quantified. In order to identify, characterize and quantify sediment dynamics in the proglacial areas a high resolution DEM of difference (DoD) between 2007 and 2012 was created and analyzed, further differentiating between different zones (e.g. valley bottom, hillslope) and types of geomorphic processes (e.g. fluvial, gravitational). First results will be presented at the EGU General Assembly 2016.

New biostratigraphic data on an Upper Hauterivian–Upper Barremian ammonite assemblage from the Dolomites (Southern Alps, Italy)

PubMed Central

Lukeneder, Alexander

2012-01-01

A biostratigraphic subdivision, based on ammonites, is proposed for the Lower Cretaceous pelagic to hemipelagic succession of the Puez area (Southern Alps, Italy). Abundant ammonites enable recognition of recently established Mediterranean ammonite zones from the upper Hauterivian Balearites balearis Zone (Crioceratites krenkeli Subzone) to the upper Barremian Gerhardtia sartousiana Zone (Gerhardtia sartousiana Subzone). Ammonites are restricted to the lowermost part of the Puez Formation, the Puez Limestone Member (ca. 50 m; marly limestones; Hauterivian–Barremian). Numerous ammonite specimens are documented for the first time from the Southern Alps (e.g., Dolomites). Ammonite abundances are clearly linked to sea-level changes from Late Hauterivian to mid Late Barremian times. Abundance and diversity peaks occur during phases of high sea-level pulses and the corresponding maximum flooding surfaces (P. mortilleti/P. picteti and G. sartousiana zones). The ammonite composition of the Puez Formation sheds light on the Early Cretaceous palaeobiogeography of the Dolomites. It also highlights the palaeoenvironmental evolution of basins and plateaus and provides insights into the faunal composition and distribution within the investigated interval. The intermittent palaeogeographic situation of the Puez locality during the Early Cretaceous serves as a key for understanding Mediterranean ammonite distribution. PMID:27087716

Human impact on the karst of the Venetian Fore-Alps, Italy

NASA Astrophysics Data System (ADS)

Sauro, U.

1993-06-01

People have been exploiting the limestone massifs of the Venetian Fore-Alps since prehistory. The fluviokarstic style of the relief and the location of springs were important controls of settlement and land use. Six principal types of exploitation are recognized and overlapped in time: (1) hunting and early farming, Paleolithic to Iron Age, with the first soil erosion; (2) general deforestation for timber, charcoal, and fuel, Roman to early modern; (3) farm enclosure and improvement, with stone clearing, medieval to modern; (4) trench warfare in World War I; (5) quarrying and specialized farming (dairy, poultry, pigs) since 1950; and (6) developmnent of modern summer and winter tourist facilities. Soil erosion effects from many centuries can still be recognized, war damage remains visible and continues to pollute aquifers, and modern pressure on the karst land and water resources is often severe.

Southern rim of Pacific Ocean basin: southern Andes to southern Alps

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dalziel, I.W.D.; Garrett, S.W.; Grunow, A.M.

1986-07-01

Between the southern Andes of Tierra del Fuego and the southern Alps of New Zealand lies the least accessible and geologically least explored part of the Pacific Ocean basin. A joint United Kingdom-United States project was initiated in 1983 to elucidate the geologic history and structure of the Pacific margin of Antarctica from the Antarctic Peninsula to Pine Island Bay at approximately lone. 105/sup 0/W. The first season (1983-1984) of this West Antarctic Tectonics Project was spent in the Ellsworth-Whitmore crustal block, and the second (1984-1985) in the Thurston Island crustal block. The project involves structural and general field geology,more » petrology, geochemistry, paleomagnetism, and airborne geophysics (magnetics and radar ice echo sounding). A final geologic season will be spent in the Pensacola Mountains of the Transantarctic Range in 1987-1988.« less

The species of the genus Diamesa (Diptera, Chironomidae) known to occur in Italian Alps and Apennines.

PubMed

Montagna, Matteo; Urbanelli, Sandra; Rossaro, Bruno

2016-11-15

Some rare species from Italian Alps, belonging to the genus Diamesa Meigen, 1835 (Diptera, Chironomidae) are here redescribed as adult males, because only old, incomplete descriptions are available for these taxa. Terminology of male genitalia is reviewed, diagnostic features are illustrated in detail, and notes on biology and geographical distribution of the examined species are provided. An identification key to the known adult males is presented.

A Spatially and Temporally Continuous LFE Catalogue for the Southern Alps, New Zealand

NASA Astrophysics Data System (ADS)

Chamberlain, C. J.; Townend, J.; Baratin, L. M.

2015-12-01

Using a brightness-based beamforming approach coupled with a matched-filter correlation method, we have developed a 6.5 year record of low-frequency earthquakes (LFEs) occuring on and near the deep extent of New Zealand's Alpine Fault. Our brightness template detection method, based on that of Frank et al. (2014), scans a pre-determined grid of possible seismic sources to automatically find LFE templates based on the stack of bandpassed squared seismic data. Previous work (Wech et al., 2012, Chamberlain et al., 2014) has shown that the depths of standard seismicity are anti-correlated with those of tremor and LFEs in the central Southern Alps: hence, by careful grid selection, shallow seismic sources can effectively be discriminated against. This beamforming approach produces many (>900) possible events. Initial beamforming detections are grouped by moveout and stacked to produce a subset of higher-quality events for use as templates in a cross-correlation detector. Events detected by cross-correlation are stacked to increase their signal-to-noise charectaristics before being located using a 3D velocity model. This method produces a spatially and temporally continuous catalogue of LFEs throughout the 6.5 year study period. The catalogue highlights quasi-continuous slow deformation occuring beneath the seismogenic zone near the Alpine Fault, punctuated by periods of increased LFE generation associated with tremor, and following large regional earthquakes. To date we have found no evidence of LFE generation north-east of Mt. Cook, the highest point in the Southern Alps, despite systematic searching throughout the region. We suggest that the along-strike cessation of tremor is due to changes in the fault's dip and the hypothesised presence of partially subducted passive margin material. This remnant passive margin would lie benath the tremor-generating region and has been linked to along-strike changes in subcrustal earthquake distributions (Boese et al., 2013).

Apomixis is not prevalent in subnival to nival plants of the European Alps

PubMed Central

Hörandl, Elvira; Dobeš, Christoph; Suda, Jan; Vít, Petr; Urfus, Tomáš; Temsch, Eva M.; Cosendai, Anne-Caroline; Wagner, Johanna; Ladinig, Ursula

2011-01-01

Background and Aims High alpine environments are characterized by short growing seasons, stochastic climatic conditions and fluctuating pollinator visits. These conditions are rather unfavourable for sexual reproduction of flowering plants. Apomixis, asexual reproduction via seed, provides reproductive assurance without the need of pollinators and potentially accelerates seed development. Therefore, apomixis is expected to provide selective advantages in high-alpine biota. Indeed, apomictic species occur frequently in the subalpine to alpine grassland zone of the European Alps, but the mode of reproduction of the subnival to nival flora was largely unknown. Methods The mode of reproduction in 14 species belonging to seven families was investigated via flow cytometric seed screen. The sampling comprised 12 species typical for nival to subnival plant communities of the European Alps without any previous information on apomixis (Achillea atrata, Androsace alpina, Arabis caerulea, Erigeron uniflorus, Gnaphalium hoppeanum, Leucanthemopsis alpina, Oxyria digyna, Potentilla frigida, Ranunculus alpestris, R. glacialis, R. pygmaeus and Saxifraga bryoides), and two high-alpine species with apomixis reported from other geographical areas (Leontopodium alpinum and Potentilla crantzii). Key Results Flow cytometric data were clearly interpretable for all 46 population samples, confirming the utility of the method for broad screenings on non-model organisms. Formation of endosperm in all species of Asteraceae was documented. Ratios of endosperm : embryo showed pseudogamous apomixis for Potentilla crantzii (ratio approx. 3), but sexual reproduction for all other species (ratios approx. 1·5). Conclusions The occurrence of apomixis is not correlated to high altitudes, and cannot be readily explained by selective forces due to environmental conditions. The investigated species have probably other adaptations to high altitudes to maintain reproductive assurance via sexuality. We

The genetic structure of the mountain forest butterfly Erebia euryale unravels the late Pleistocene and postglacial history of the mountain coniferous forest biome in Europe.

PubMed

Schmitt, Thomas; Haubrich, Karola

2008-05-01

The distribution of the mountain coniferous forest biome in Europe throughout time is not sufficiently understood. One character species of this habitat type is the large ringlet, Erebia euryale well reflecting the extension of this biome today, and the genetic differentiation of this species among and within mountain systems may unravel the late Pleistocene history of this habitat type. We therefore analysed the allozyme pattern of 381 E. euryale individuals from 11 populations in four different European mountain systems (Pyrenees, Alps, Carpathians, Rila). All loci analysed were polymorphic. The mean F(ST) over all samples was high (20%). Furthermore, the mean genetic distance among samples was quite high (0.049). We found four different groups well supported by cluster analyses, bootstraps and hierarchical variance analyses: Pyrenees, western Alps, eastern Alps and southeastern Europe (Carpathians and Rila). The genetic diversity of the populations was highest in the southeastern European group and stepwise decreased westwards. Interestingly, the populations from Bulgaria and Romania were almost identical; therefore, we assume that they were not separated by the Danube Valley, at least during the last ice age. On the contrary, the differentiation among the three western Alps populations was considerable. For all these reasons, we assume that (i) the most important refugial area for the coniferous mountain forest biome in Europe has been located in southeastern Europe including at least parts of the Carpathians and the Bulgarian mountains; (ii) important refugial areas for this biome existed at the southeastern edge of the Alps; (iii) fragments of this habitat types survived along the southwestern Alps, but in a more scattered distribution; and (iv) relatively small relicts have persisted somewhere at the foothills of the Pyrenees.

Potential improvement of Schmidt-hammer exposure-age dating (SHD) of moraines in the Southern Alps, New Zealand, by application of the new electronic Schmidt-hammer (SilverSchmidt)

NASA Astrophysics Data System (ADS)

Winkler, Stefan; Corbett, David

2014-05-01

. Winkler, S. (2009): First attempt to combine terrestrial cosmogenic nuclide (10Be) and Schmidt hammer relative-age dating: Strauchon Glacier, Southern Alps, New Zealand. Central European Journal of Geosciences 1, 274 - 290. Winkler, S. (2013): Investigation of late-Holocene moraines in the western Southern Alps, New Zealand, applying Schmidt-hammer exposure-age dating (SHD). The Holocene (online), doi: 10.1177/0959683613512169.

A new species of Isoperla (Insecta, Plecoptera) from the Karawanken, with considerations on the Southern Limestone Alps as centers of endemism.

PubMed

Graf, Wolfram; Konar, Martin; Murányi, Dávid; Orci, Kirill Márk; Vitecek, Simon

2014-01-01

A new species of the genus Isoperla (Plecoptera, Perlodidae), belonging to the oxylepis species-group is described, and the male mating call is characterized. Its range falls within a small region of the Southern Limestone Alps which is well known to be one endemism-centre of aquatic insects.

Tracking an upper limit of the "Carnian Crisis" and/or Carnian stage in the Western Carpathians (Slovakia)

NASA Astrophysics Data System (ADS)

Kohút, Milan; Hofmann, Mandy; Havrila, Milan; Linnemann, Ulf; Havrila, Jakub

2018-01-01

The Late Triassic timescale, especially the Carnian-Norian boundary, is poorly constrained mainly due to a paucity of high-precision radio-isotopic ages that can be related accurately to contradictions between the biostratigraphic and magnetostratigraphic correlations. LA ICP-MS dating of detrital zircons from five samples of the Lunz Formation—the Upper Triassic siliciclastic sediments from the Western Carpathians (Slovakia)—provided a wide spectrum of ages that vary from Late Archaean (ca. 2582 Ma) to Triassic (ca. 216 Ma). These marine delta sediments represent a typical product of the "Carnian Crisis"—a major climate change and biotic turnover that occurred during the Carnian stage in the Tethys Ocean within the carbonate shelf and intrashelf basins in the Northern Calcareous Alps and the Western Carpathians. The supply of clastic material in the studied Lunz Formation was derived from several sources, especially: (i) from the recycled Variscan orogen; (ii) from the remote East European Platform; and (iii) from the contemporaneous Triassic volcanic sources. Syn-sedimentary volcanic zircons with a concordia age of 221.2 ± 1.6 Ma (calculated from 12 single analyses) represent the maximum age of deposition of the Lunz Formation, and demonstrate that the upper limit of the "Carnian Crisis" and/or the Carnian stage in the Alpine-Carpathians realm is younger than the current age of the Carnian-Norian boundary at ca. 227 Ma listed on the International Chronostratigraphic Chart (International Commission on Stratigraphy 2016/12 Edition).

Dendroclimatic trend and glacial fluctuations in the Central Italian Alps

NASA Astrophysics Data System (ADS)

Pelfini, M.; Santilli, M.; D Agata, C.; Diolaiuti, G.; Smiraglia, C.

2003-04-01

In the Alpine environment, one of the main limiting factors for tree growth is the thermal conditions of the vegetative season. The conifers at high altitude, if not subject to others disturbs, such as geomorphological processes or biological interferences, undergo a development, from which the width of annual rings depends. Five chronologies few centuries long, obtained for the species Larix decidua Mill. and Pinus cembra L. from different valleys of the Central Italian Alps (Alpisella, Valfurva, Gavia and Solda) in proximity of timberline (2000-2550 m of altitude), were analysed and their climatic signal gained; this last one was then related to the recent glacial fluctuations. The chronologies are the averages of many dendrochronological indicized curves obtained from dominant trees with regular growth and extended from 13th-17th century up to the present. The time intervals of the chronologies are the following ones: Pinus cembra: 1752-1999 for Valfurva; 1607-1999 for Gavia; 1593-1999 for Val Solda. With regard to Larix decidua: 1252-1998 for Val Solda; 1784-2001 for Alpisella. The good correspondence between the various chronologies allows to consider them representative of the climatic regional signal. In order to evidence climatic evolution, linear trends based on running mean with period of 11 years have been constructed. Those curves have been compared between them and then overlapped and mediated in order to obtain a climatic signal of regional value that excludes eventual local anomalies. Finally, the growth variations in the chronologies have been compared to known alpine climatic variations and glacial fluctuations. In particular time-distance curves (curves of cumulated frontal variations) of some glaciers from the Ortles-Cevedale Group were utilized. The periods of tree rings growth rate reduction appear well correlated to glacial advancing phases of the Little Ice Age and of the following phases. In particular, growth rate reductions are observable

Permafrost Favourability Index: Spatial modelling in the French Alps using a Rock Glacier Inventory

NASA Astrophysics Data System (ADS)

Marcer, Marco; Bodin, Xavier; Brenning, Alexander; Schoeneich, Philippe; Charvet, Raphaële; Gottardi, Frédéric

2017-12-01

In the present study we used the first rock glacier inventory for the entire French Alps to model spatial permafrost distribution in the region. The inventory, which does not originally belong to this study, was revised by the authors in order to obtain a database suitable for statistical modelling. Climatic and topographic data evaluated at the rock glacier locations were used as predictor variables in a Generalized Linear Model. Model performances are strong, suggesting that, in agreement with several previous studies, this methodology is able to model accurately rock glacier distribution. A methodology to estimate model uncertainties is proposed, revealing that the subjectivity in the interpretation of rock glacier activity and contours may substantially bias the model. The model highlights a North-South trend in the regional pattern of permafrost distribution which is attributed to the climatic influences of the Atlantic and Mediterranean climates. Further analysis suggest that lower amounts of precipitation in the early winter and a thinner snow cover, as typically found in the Mediterranean area, could contribute to the existence of permafrost at higher temperatures compared to the Northern Alps. A comparison with the Alpine Permafrost Index Map (APIM) shows no major differences with our model, highlighting the very good predictive power of the APIM despite its tendency to slightly overestimate permafrost extension with respect to our database. The use of rock glaciers as indicators of permafrost existence despite their time response to climate change is discussed and an interpretation key is proposed in order to ensure the proper use of the model for research as well as for operational purposes.

Gravity Wave Breaking over the Central Alps: Role of Complex Terrain.

NASA Astrophysics Data System (ADS)

Jiang, Qingfang; Doyle, James D.

2004-09-01

The characteristics of gravity waves excited by the complex terrain of the central Alps during the intensive observational period (IOP) 8 of the Mesoscale Alpine Programme (MAP) is studied through the analysis of aircraft in situ measurements, GPS dropsondes, radiosondes, airborne lidar data, and numerical simulations.Mountain wave breaking occurred over the central Alps on 21 October 1999, associated with wind shear, wind turning, and a critical level with Richardson number less than unity just above the flight level (5.7 km) of the research aircraft NCAR Electra. The Electra flew two repeated transverses across the Ötztaler Alpen, during which localized turbulence was sampled. The observed maximum vertical motion was 9 m s-1, corresponding to a turbulent kinetic energy (TKE) maximum of 10.5 m2 s-2. Spectrum analysis indicates an inertia subrange up to 5-km wavelength and multiple energy-containing spikes corresponding to a wide range of wavelengths.Manual analysis of GPS dropsonde data indicates the presence of strong flow descent and a downslope windstorm over the lee slope of the Ötztaler Alpen. Farther downstream, a transition occurs across a deep hydraulic jump associated with the ascent of isentropes and local wind reversal. During the first transverse, the turbulent region is convectively unstable as indicated by a positive sensible heat flux within the turbulent portion of the segment. The TKE derived from the flight-level data indicates multiple narrow spikes, which match the patterns shown in the diagnosed buoyancy production rate of TKE. The turbulence is nonisotropic with the major TKE contribution from the -wind component. The convectively unstable zone is advected downstream during the second transverse and the turbulence becomes much stronger and more isotropic.The downslope windstorm, flow descent, and transition to turbulence through a hydraulic jump are captured by a real-data Coupled Ocean Atmosphere Mesoscale Predition System (COAMPS

Structures, microfabrics and textures of the Cordilleran-type Rechnitz metamorphic core complex, Eastern Alps☆

PubMed Central

Cao, Shuyun; Neubauer, Franz; Bernroider, Manfred; Liu, Junlai; Genser, Johann

2013-01-01

Rechnitz window group represents a Cordilleran-style metamorphic core complex, which is almost entirely located within nearly contemporaneous Neogene sediments at the transition zone between the Eastern Alps and the Neogene Pannonian basin. Two tectonic units are distinguished within the Rechnitz metamorphic core complex (RMCC): (1) a lower unit mainly composed of Mesozoic metasediments, and (2) an upper unit mainly composed of ophiolite remnants. Both units are metamorphosed within greenschist facies conditions during earliest Miocene followed by exhumation and cooling. The internal structure of the RMCC is characterized by the following succession of structure-forming events: (1) blueschist relics of Paleocene/Eocene age formed as a result of subduction (D1), (2) ductile nappe stacking (D2) of an ophiolite nappe over a distant passive margin succession (ca. E–W to WNW–ESE oriented stretching lineation), (3) greenschist facies-grade metamorphism annealing dominant in the lower unit, and (4) ductile low-angle normal faulting (D3) (with mainly NE–SW oriented stretching lineation), and (5) ca. E to NE-vergent folding (D4). The microfabrics are related to mostly ductile nappe stacking to ductile low-angle normal faulting. Paleopiezometry in conjunction with P–T estimates yield high strain rates of 10− 11 to 10− 13 s− 1, depending on the temperature (400–350 °C) and choice of piezometer and flow law calibration. Progressive microstructures and texture analysis indicate an overprint of the high-temperature fabrics (D2) by the low-temperature deformation (D3). Phengitic mica from the Paleocene/Eocene high-pressure metamorphism remained stable during D2 ductile deformation as well as preserved within late stages of final sub-greenschist facies shearing. Chlorite geothermometry yields two temperature groups, 376–328 °C, and 306–132 °C. Chlorite is seemingly accessible to late-stage resetting. The RMCC underwent an earlier large-scale coaxial

A new species of Isoperla (Insecta, Plecoptera) from the Karawanken, with considerations on the Southern Limestone Alps as centers of endemism

PubMed Central

Graf, Wolfram; Konar, Martin; Murányi, Dávid; Orci, Kirill Márk; Vitecek, Simon

2014-01-01

Abstract A new species of the genus Isoperla (Plecoptera, Perlodidae), belonging to the oxylepis species-group is described, and the male mating call is characterized. Its range falls within a small region of the Southern Limestone Alps which is well known to be one endemism-centre of aquatic insects. PMID:25408608

Kinematic reconstruction of a thin-skinned, deep-water fold and thrust belt: the case of the Outer Tuscan Nappe (Umbria, Italy)

NASA Astrophysics Data System (ADS)

Carboni, Filippo; Barchi, Massimiliano; Brozzetti, Francesco; Cruciani, Francesco; Ercoli, Maurizio; Mirabella, Francesco; Porreca, Massimiliano

2017-04-01

Fold-and-Thrust Belts occur worldwide in a variety of tectonic settings. Most of them develop in a deepwater environment (Deep Water Fold-and-Thrust Belts, DWFTBs), at both continental passive and active margins, driven by gravity (near-field stresses) and tectonic forces (far-field stresses) respectively. Here we present a multidisciplinary geological study of the Outer Tuscan Nappe (OTN), an imbricate thrust system in the Northern Apennines of Italy, emplaced in Early Miocene times in deep water environment. Despite the wide scientific literature, the geometry and the kinematic evolution of the OTN were never reconstructed in detail. Furthermore, its total amount of shortening and then its shortening rate, were never measured and calculated through proper restoration techniques. The OTN involves a 2000 m thick, Late Cretaceous-Tertiary "Tuscan" succession, consisting of arenaceous turbidites (Macigno Fm.), overlying a thick level of marls and calcarenites (Scaglia Toscana Fm.), which form the major basal décollement of the imbricate system. Along this basal décollement, the OTN overthrusts eastward younger turbidite units (Mt. Rentella and Marnoso-Arenacea successions). In this study we interpreted a set of 2D seismic reflection profiles calibrated with a deep borehole, crossing transversally (WSW-ENE) and longitudinally (NNW-SSE) the OTN. To better constrain the interpretation, selected controls of key outcrops was performed, mainly aimed at reconstructing: i) the actual transport direction during the OTN emplacement; ii) the position of the subsequent, NNW-SSE trending, extensional faults dissecting the tectonic wedge; iii) the role of transversal faults, longitudinally segmenting the thrust system. Combining the aforesaid data, we drew an integrated 20 km long geological cross section showing the internal geometry of the imbricate thrust system, down to the main basal décollement. The integrated section was successively restored in 2D using the software

Zooplankton communities and Bythotrephes longimanus in lakes of the montane region of the northern Alps

PubMed Central

Horváth, Zsófia; Vad, Csaba F.; Preiler, Christian; Birtel, Julia; Matthews, Blake; Ptáčníková, Radka; Ptáčník, Robert

2017-01-01

Abstract Lakes in the Alps represent a considerable fraction of nutrient-poor lakes in Central Europe, with unique biodiversity and ecosystem properties. Although some individual lakes are well studied, less knowledge is available on large-scale patterns essential to general understanding of their functioning. Here, we aimed to describe crustacean zooplankton communities (Cladocera, Copepoda) and identify their environmental drivers in the pelagic zone of 54 oligotrophic lakes in the montane region of the Alps (400–1200 m) in Austria, Germany, and Switzerland, covering a spatial scale of 650 km. Moreover, we aimed to provide data on the distribution and ecological requirements of the North American invader Bythotrephes longimanus in its Central European native range. Communities were mainly dominated by widespread species typical of lowland habitats, and only a few true specialists of oligotrophic alpine lakes were present. The most frequent taxa were the Daphnia longispina complex and Eudiaptomus gracilis, with 48 and 45 occurrences, respectively. Species richness decreased with altitude and increased with lake area. The main structuring factors of community composition were chlorophyll a concentration and depth, which drove an apparent separation of mesotrophic and oligotrophic communities. Bythotrephes had 13 occurrences, showing a preference for deep oligotrophic lakes. Its presence was not coupled with lower crustacean species richness, as was repeatedly observed in North America. Additionally, it frequently co-occurred with the other large predatory cladoceran, Leptodora kindtii. B. longimanus might be considered a truly montane species in Central Europe, given its absence in lowland and alpine lakes. PMID:28824797

Zooplankton communities and Bythotrephes longimanus in lakes of the montane region of the northern Alps

PubMed Central

Horváth, Zsófia; Vad, Csaba F.; Preiler, Christian; Birtel, Julia; Matthews, Blake; Ptáčníková, Radka; Ptacnik, Robert

2017-01-01

Lakes in the Alps represent a considerable fraction of nutrient-poor lakes in Central Europe, with unique biodiversity and ecosystem properties. Although some individual lakes are well-studied, less knowledge is available on large-scale patterns essential to generalise the understanding of their functioning. Here, we aimed to describe crustacean zooplankton communities (Cladocera, Copepoda) and identify their environmental drivers in the pelagic zone of 54 oligotrophic lakes in the montane region of the Alps (400–1200 m) in Austria, Germany, and Switzerland, covering a spatial scale of 650 km. Moreover, we aimed to provide data on the distribution and ecological requirements of the North American invader Bytotrephes longimanus in its Central European native range. Communities were mainly dominated by widespread species typical of lowland habitats, and only a few true specialists of oligotrophic alpine lakes were present. The most frequent taxa were the Daphnia longispina complex and Eudiaptomus gracilis, with 48 and 45 occurrences, respectively. Species richness decreased with altitude and increased with lake area. The main structuring factors of community composition were chlorophyll a concentration and depth, which drove an apparent separation of mesotrophic and oligotrophic communities. Bytotrephes had 13 occurrences, showing a preference for deep oligotrophic lakes. Its presence was not coupled with lower crustacean species richness as it was repeatedly observed in North America. Additionally, it frequently co-occurred with the other large predatory cladoceran, Leptodora kindtii. B. longimanus might be considered a truly montane species in Central Europe, given its absence in lowland and alpine lakes. PMID:28649318

Conservation of brown bear in the Alps: space use and settlement behavior of reintroduced bears

NASA Astrophysics Data System (ADS)

Preatoni, Damiano; Mustoni, Andrea; Martinoli, Adriano; Carlini, Eugenio; Chiarenzi, Barbara; Chiozzini, Simonetta; Van Dongen, Stefan; Wauters, Luc A.; Tosi, Guido

2005-11-01

Large carnivores typically need large home ranges containing habitats patches of different quality. Consequently, their conservation requires habitat protection and management at the landscape scale. In some cases, reintroduction might be used to support remnant or restore extinct populations. This is the case for the brown bear ( Ursus arctos) in the Italian Alps. We monitored spacing behavior and settlement of reintroduced brown bears in Adamello-Brenta Natural Park, North-Italy, using radio-tracking. Habitat use, dispersion and survival were studied to evaluate the success of reintroduction and possible conflicts with man. All three males and five of seven females settled in the study area. Most bears roamed widely the first months after release, exploring the new habitat. Patterns of home range overlap between seasons and years revealed that home range use stabilized the year after first hibernation. Home ranges were larger in the mating season (May-July) than in spring or autumn. Home ranges varied between 34 and 1813 km 2 the year after release, but core-areas, where feeding activity was concentrated, were much smaller. Some bears had exclusive core-areas in summer and autumn, but most showed considerable core-area overlap with animals of the same and/or the opposite sex. Bears selected deciduous forests, mixed and conifer forests were used according to availability, and areas with anthropogenic disturbance were avoided. Most bears settled and some reproduced successfully at the release site, causing high initial population growth, suggesting that reintroduction can help to re-establish a brown bear population in the Italian Alps.

Production of Hybrids between Western Gray Wolves and Western Coyotes

PubMed Central

Mech, L. David; Christensen, Bruce W.; Asa, Cheryl S.; Callahan, Margaret; Young, Julie K.

2014-01-01

Using artificial insemination we attempted to produce hybrids between captive, male, western, gray wolves (Canis lupus) and female, western coyotes (Canis latrans) to determine whether their gametes would be compatible and the coyotes could produce and nurture offspring. The results contribute new information to an ongoing controversy over whether the eastern wolf (Canis lycaon) is a valid unique species that could be subject to the U. S. Endangered Species Act. Attempts with transcervically deposited wolf semen into nine coyotes over two breeding seasons yielded three coyote pregnancies. One coyote ate her pups, another produced a resorbed fetus and a dead fetus by C-section, and the third produced seven hybrids, six of which survived. These results show that, although it might be unlikely for male western wolves to successfully produce offspring with female western coyotes under natural conditions, western-gray-wolf sperm are compatible with western-coyote ova and that at least one coyote could produce and nurture hybrid offspring. This finding in turn demonstrates that gamete incompatibility would not have prevented western, gray wolves from inseminating western coyotes and thus producing hybrids with coyote mtDNA, a claim that counters the view that the eastern wolf is a separate species. However, some of the difficulties experienced by the other inseminated coyotes tend to temper that finding and suggest that more experimentation is needed, including determining the behavioral and physical compatibility of western gray wolves copulating with western coyotes. Thus although our study adds new information to the controversy, it does not settle it. Further study is needed to determine whether the putative Canis lycaon is indeed a unique species. PMID:24586418

Production of hybrids between western gray wolves and western coyotes.

PubMed

Mech, L David; Christensen, Bruce W; Asa, Cheryl S; Callahan, Margaret; Young, Julie K

2014-01-01

Using artificial insemination we attempted to produce hybrids between captive, male, western, gray wolves (Canis lupus) and female, western coyotes (Canis latrans) to determine whether their gametes would be compatible and the coyotes could produce and nurture offspring. The results contribute new information to an ongoing controversy over whether the eastern wolf (Canis lycaon) is a valid unique species that could be subject to the U. S. Endangered Species Act. Attempts with transcervically deposited wolf semen into nine coyotes over two breeding seasons yielded three coyote pregnancies. One coyote ate her pups, another produced a resorbed fetus and a dead fetus by C-section, and the third produced seven hybrids, six of which survived. These results show that, although it might be unlikely for male western wolves to successfully produce offspring with female western coyotes under natural conditions, western-gray-wolf sperm are compatible with western-coyote ova and that at least one coyote could produce and nurture hybrid offspring. This finding in turn demonstrates that gamete incompatibility would not have prevented western, gray wolves from inseminating western coyotes and thus producing hybrids with coyote mtDNA, a claim that counters the view that the eastern wolf is a separate species. However, some of the difficulties experienced by the other inseminated coyotes tend to temper that finding and suggest that more experimentation is needed, including determining the behavioral and physical compatibility of western gray wolves copulating with western coyotes. Thus although our study adds new information to the controversy, it does not settle it. Further study is needed to determine whether the putative Canis lycaon is indeed a unique species.

Production of hybrids between western gray wolves and western coyotes

USGS Publications Warehouse

Mech, L. David; Christensen, Bruce W.; Asa, Cheryl S.; Callahan, Margaret; Young, Julie K.

2014-01-01

Using artificial insemination we attempted to produce hybrids between captive, male, western, gray wolves (Canis lupus) and female, western coyotes (Canis latrans) to determine whether their gametes would be compatible and the coyotes could produce and nurture offspring. The results contribute new information to an ongoing controversy over whether the eastern wolf (Canis lycaon) is a valid unique species that could be subject to the U. S. Endangered Species Act. Attempts with transcervically deposited wolf semen into nine coyotes over two breeding seasons yielded three coyote pregnancies. One coyote ate her pups, another produced a resorbed fetus and a dead fetus by C-section, and the third produced seven hybrids, six of which survived. These results show that, although it might be unlikely for male western wolves to successfully produce offspring with female western coyotes under natural conditions, western-gray-wolf sperm are compatible with western-coyote ova and that at least one coyote could produce and nurture hybrid offspring. This finding in turn demonstrates that gamete incompatibility would not have prevented western, gray wolves from inseminating western coyotes and thus producing hybrids with coyote mtDNA, a claim that counters the view that the eastern wolf is a separate species. However, some of the difficulties experienced by the other inseminated coyotes tend to temper that finding and suggest that more experimentation is needed, including determining the behavioral and physical compatibility of western gray wolves copulating with western coyotes. Thus although our study adds new information to the controversy, it does not settle it. Further study is needed to determine whether the putative Canis lycaon is indeed a unique species.

Triassic metasediments in the internal Dinarides (Kopaonik area, southern Serbia): stratigraphy, paleogeographic and tectonic significance

NASA Astrophysics Data System (ADS)

Schefer, Senecio; Egli, Daniel; Missoni, Sigrid; Bernoulli, Daniel; Fügenschuh, Bernhard; Gawlick, Hans-Jürgen; Jovanović, Divna; Krystyn, Leopold; Lein, Richard; Schmid, Stefan M.; Sudar, Milan N.

2010-04-01

Strongly deformed and metamorphosed sediments in the Studenica Valley and Kopaonik area in southern Serbia expose the easternmost occurrences of Triassic sediments in the Dinarides. In these areas, Upper Paleozoic terrigenous sediments are overlain by Lower Triassic siliciclastics and limestones and by Anisian shallow-water carbonates. A pronounced facies change to hemipelagic and distal turbiditic, cherty metalimestones (Kopaonik Formation) testifies a Late Anisian drowning of the former shallow-water carbonate shelf. Sedimentation of the Kopaonik Formation was contemporaneous with shallow-water carbonate production on nearby carbonate platforms that were the source areas of diluted turbidity currents reaching the depositional area of this formation. The Kopaonik Formation was dated by conodont faunas as Late Anisian to Norian and possibly extends into the Early Jurassic. It is therefore considered an equivalent of the grey Hallstatt facies of the Eastern Alps, the Western Carpathians, and the Albanides-Hellenides. The coeval carbonate platforms were generally situated in more proximal areas of the Adriatic margin, whereas the distal margin was dominated by hemipelagic/pelagic and distal turbiditic sedimentation, facing the evolving Neotethys Ocean to the east. A similar arrangement of Triassic facies belts can be recognized all along the evolving Meliata-Maliac-Vardar branch of Neotethys, which is in line with a ‘one-ocean-hypothesis’ for the Dinarides: all the ophiolites presently located southwest of the Drina-Ivanjica and Kopaonik thrust sheets are derived from an area to the east, and the Drina-Ivanjica and Kopaonik units emerge in tectonic windows from below this ophiolite nappe. On the base of the Triassic facies distribution we see neither argument for an independent Dinaridic Ocean nor evidence for isolated terranes or blocks.

Regional glacier changes in the Ötztal Alps (Tyrol, Austria) - Results from different remote sensing techniques

NASA Astrophysics Data System (ADS)

Klug, Christoph; Rieg, Lorenzo; Sailer, Rudolf

2017-04-01

Climate change will pose a variety of challenges in the future, with global sea level rise among the most important ones. Out of all contributions to sea level rise, the contribution from glaciers is the one with the highest uncertainty. This is mainly because only very few and not necessarily representative glaciers are measured regularly. Among others, this limits the validation of extrapolation models. On a regional scale, remote sensing data offer several possibilities for the mapping and monitoring of glaciers. Especially with the advent of very high resolution data, new possibilities can be exploited. The monitoring of glacier area, the calculation of the geodetic glacier mass balances and the tracking of changes in the seasonal snow and firn bodies of glaciers on a regional scale can not only help to enhance the spatial, but also the temporal coverage of observations. The Ötztal Alps in Tyrol, Austria have been a research focus for the University of Innsbruck for several decades. Ongoing glaciological field measurements at two reference glaciers (Hintereisferner and Kesselwandferner) and data from different remote sensing techniques provide a valuable basis for a variety of research. The presented study analyses high-resolution airborne laser scanning (ALS) data, with more than 10 years of annual campaigns on Hintereisferner (2001-2013) and two campaigns covering all of the Ötztal Alps (2006 and 2010) in combination with orthoimages and optical satellite data. Furthermore Pléiades tri-stereo data (2015 and 2016) are available to calculate very high resolution and high quality digital terrain models (DTM). These DTM can be used to extend the time series in combination with the DTM based on ALS data and enable the calculation of the geodetic glacier mass balance for over 150 glaciers within the study area. Furthermore, the optical information (ALS intensity, orthoimages and optical satellite data) is used for surface classification in order to monitor the

Origin and age of zircon-bearing chromitite layers from the Finero phlogopite peridotite (Ivrea-Verbano Zone, Western Alps) and geodynamic consequences

NASA Astrophysics Data System (ADS)

Zanetti, Alberto; Giovanardi, Tommaso; Langone, Antonio; Tiepolo, Massimo; Wu, Fu-Yuan; Dallai, Luigi; Mazzucchelli, Maurizio

2016-10-01

An investigation has been performed on three chromitite layers segregated in dunite bodies of the Phlogopite Peridotite mantle unit in the Finero complex (FPP, Ivrea-Verbano Zone, Southern Alps) aimed at providing new constraints to their origin and evolution. Field relationships, the sub-chondritic Hf isotopic composition of the zircons (εHf(188) as low as - 5.4), the heavy O isotopic composition of zircons and pyroxenes (δ18O up to 6.9‰), the strict similarity of the trace element composition between the clinopyroxenes and amphiboles from the chromitites and those from the phlogopite harzburgites and pyroxenites forming the typical FPP association, as well as the REE composition of zircons, which approaches equilibrium with the associate clinopyroxene, suggest that the studied chromitites were segregated from melts, highly contaminated from continental crust, during the pervasive cycle of metasomatism recorded by the FPP. An LA-ICP-HRMS survey of chromitite zircon grains has provided Early Jurassic U-Pb ages mostly between 199 ± 3 Ma and 178 ± 2 Ma, with a pronounced peak at 187 Ma. Relevant exceptions are inherited domains of two grains giving Triassic ages of 242 ± 7 Ma and 229 ± 7 Ma, and a third homogeneous zircon giving 208 ± 3 Ma. Our geochronological data and those reported in the literature show that the FPP chromitites have zircon populations with different internal CL textures, but the same sub-chondritic Hf isotopic composition, which define an overall U-Pb age span from 290 Ma to 180. The segregation of the chromitite layers and the main pervasive metasomatism likely occurred in the Early Permian (in a post-collisional, transtensional setting) or before (possibly, in a subduction-related setting). The rejuvenation of the zircon ages was accompanied by a progressive disappearance of the internal zoning, interpreted as the result of a prolonged residence at mantle depths with progressive re-equilibration of the U-Pb system due to thermal

7th Cancer Scientific Forum of the Cancéropôle Lyon Auvergne Rhône-Alpes

PubMed Central

Pauwels, Petrus J.; Dumontet, Charles; Reichert, Janice M.; Beck, Alain; Goetsch, Liliane; Corvaïa, Nathalie; Klein, Christian; Coiffier, Bertrand; Teicher, Beverly A.

2012-01-01

The Innovative Approaches in Anti-Cancer Monoclonal Antibodies meeting, held on March 20, 2012 in Lyon, was organized by Cancéropôle Lyon Auvergne-Rhône-Alps in partnership with the French competitiveness cluster Lyonbiopôle. CLARA is one of the seven cancer research clusters within France in charge of facilitating Translational Oncology Research by taking into account the objectives of the French National Cancer Plans I and II and, in coordination with the French National Cancer Institute and local authorities (mainly Grand Lyon, Rhône County and Rhône-Alpes Region), to perform economic development of research findings. The contribution of lectures by outstanding speakers as described in this report, the organization of two-round tables: “Antibody treatment in cancer: Unmet needs in solid tumors and hematological malignancies,” and “From chimeric to more than human antibodies,” together with face-to-face meetings, was shared by over 230 participants. The lectures provided an overview of the commercial pipeline of monoclonal antibody (mAb) therapeutics for cancer; discussion of the distinction between biosimilar, biobetter and next generation therapeutic antibodies for cancer; updates on obinutuzumab and the use of mAbs in lymphoma; and discussion of antibody-drug conjugates. PMID:22684281

Fog Chemistry at Different Altitudes in the Swiss Alps

NASA Astrophysics Data System (ADS)

Michna, P.; Eugster, W.; Wanner, H.

2010-07-01

During two extended summer seasons in 2006 and 2007, we installed two battery driven versions of the Caltech active strand cloud water collector (MiniCASCC) at the Niesen mountain in the northern Swiss Alps. Along, we measured air temperature, relative humidity, wind, and visibility. During these two field operation phases we gained weekly samples of fogwater, where we analysed the major anions and cations, and the stable water isotopes δD and δ18O. The fog collectors were installed at an altitude of 2300 and 1600 m asl to resolve altitudinal differences in fog chemistry. We found a large variability between the events, but no clear altitudinal gradient. At both sites, the most important ions were nitrate, ammonium, and sulphate. Higher concentrations occured preferably in late spring (start of sampling period) and in autumn (end of sampling). Compared to previous studies at lower elevations in the Swiss Plateau during wintertime, our measurements showed considerable lower ion loads in the fogwater. The combination of these results suggest that lowest ion loads are found in convective clouds with a short lifetime and that the highest ion loads occur during radiation fog events at lower elevations.

Little Ice Age mapping as a tool for identifying hazard in the paraglacial environment: The case study of Trentino (Eastern Italian Alps)

NASA Astrophysics Data System (ADS)

Zanoner, Thomas; Carton, Alberto; Seppi, Roberto; Carturan, Luca; Baroni, Carlo; Salvatore, Maria Cristina; Zumiani, Matteo

2017-10-01

The Little Ice Age (LIA) is a well-recognized climatic event during which the glaciers in the Alps advanced and reached their maximum Holocene extent. During their retreat following the LIA, the glaciers left large areas of loose or poorly consolidated glacial deposits in their forelands, which are subject to paraglacial reworking and may represent potential hazards for human infrastructures. In this study, we present a regional scale mapping of the LIA and post-LIA glacial deposits and a reconstruction of the maximum LIA extents of glaciers in the same area. This work is motivated by a local law requiring the classification of areas subject to natural hazards in Trentino (Italian Alps). Results highlight that glaciers shrunk by 63% from the LIA maximum, leaving 30 km2 of unconsolidated deposits, which are subject to geomorphic paraglacial processes. Potentially hazardous consequences can occur, in particular, during high-magnitude instantaneous events, causing debris and mud flows, mass wasting from debris-covered ice, and floods from small moraine-dammed lakes.

New species of aquatic insects from Europe (Insecta: Trichoptera): Alps and Pyrenees as harbours of unknown biodiversity

PubMed Central

GRAF, WOLFRAM; VITECEK, SIMON; PREVIŠIĆ, ANA; MALICKY, HANS

2016-01-01

New species are described from the following genera: Consorophylax and Anisogamus, (Trichoptera, Limnephilidae). Additionally the larvae of the genus Anisogamus, and the larval stages of Anisogamus waringeri nov. sp. and A. difformis (McLachlan 1867) are described. The new species Consorophylax vinconi sp. nov. is a microendemic from the Southern Alps and differs distinctly from its congeners in the shape of the parameres, which are distinctly straitened in the distal quarter in the new species. The new species Anisogamus waringeri sp. nov. represents the second species in the hitherto monospecific genus Anisogamus. Compared to Anisogamus difformis, A. waringeri sp. nov. develops more slender superior appendages; a more rounded basal plate of the intermediate appendages, lacking pointed protuberances; and parameres shorter than the aedaegus, proximally with one dorsal and several ventral tines. Further, the two species are disjunctly distributed in the European mountain ranges (A. difformis: Alps, A. waringeri sp. nov.: Pyrenees). Larvae of the genus Anisogamus are characterized by the lack of a dorsal protuberance on the 1st abdominal segment, a unique feature among Limnephilidae. Anisogamus difformis and A. waringeri sp. nov. larvae differ in pronotum shape. The recovery of two new species demonstrates the significance of taxonomic studies in Europe, and the importance of adequate training for young scientists in order to assess a biodiversity under threat of extinction that has yet to be fully described. PMID:25661619

Genetic Differentiation of the Western Capercaillie Highlights the Importance of South-Eastern Europe for Understanding the Species Phylogeography

PubMed Central

Ballian, Dalibor; Kunovac, Saša; Zubić, Goran; Grubešić, Marijan; Zhelev, Petar; Paule, Ladislav; Grebenc, Tine; Kraigher, Hojka

2011-01-01

The Western Capercaillie (Tetrao urogallus L.) is a grouse species of open boreal or high altitude forests of Eurasia. It is endangered throughout most mountain range habitat areas in Europe. Two major genetically identifiable lineages of Western Capercaillie have been described to date: the southern lineage at the species' southernmost range of distribution in Europe, and the boreal lineage. We address the question of genetic differentiation of capercaillie populations from the Rhodope and Rila Mountains in Bulgaria, across the Dinaric Mountains to the Slovenian Alps. The two lineages' contact zone and resulting conservation strategies in this so-far understudied area of distribution have not been previously determined. The results of analysis of mitochondrial DNA control region sequences of 319 samples from the studied populations show that Alpine populations were composed exclusively of boreal lineage; Dinaric populations of both, but predominantly (96%) of boreal lineage; and Rhodope-Rila populations predominantly (>90%) of southern lineage individuals. The Bulgarian mountains were identified as the core area of the southern lineage, and the Dinaric Mountains as the western contact zone between both lineages in the Balkans. Bulgarian populations appeared genetically distinct from Alpine and Dinaric populations and exhibited characteristics of a long-term stationary population, suggesting that they should be considered as a glacial relict and probably a distinct subspecies. Although all of the studied populations suffered a decline in the past, the significantly lower level of genetic diversity when compared with the neighbouring Alpine and Bulgarian populations suggests that the isolated Dinaric capercaillie is particularly vulnerable to continuing population decline. The results are discussed in the context of conservation of the species in the Balkans, its principal threats and legal protection status. Potential conservation strategies should consider the

Summer mistral at the exit of the Rhône valley

NASA Astrophysics Data System (ADS)

Drobinski, P.; Bastin, S.; Guenard, V.; Caccia, J. L.; Dabas, A. M.; Delville, P.; Protat, A.; Reitebuch, O.; Werner, C.

2005-01-01

The paper examines the three-dimensional structure and dynamics of the mistral at the Rhône valley exit on 28 June 2001. The mistral refers to a severe wind that develops along the Rhône valley in southern France. This summer mistral event was documented in the framework of the ESCOMPTE field experiment. The dynamical processes driving the circulation of the mistral in the Rhône valley and particularly wake formation and planetary boundary layer (PBL) inhomogeneity at the scale of Rhône valley delta are investigated. Several important data sources are used (airborne Doppler lidar, radiosondes and surface stations) as well as non-hydrostatic mesoscale simulations. This paper analyses experimentally, numerically and theoretically the mechanism of wake formation. It shows that the flow impinging on the Alpine range and the Massif Central becomes supercritical all along the ridge line, including the Rhône valley and continues to accelerate in the lee regions until a hydraulic jump occurs. It leads to the formation of wakes behind and close to the mountain peaks. Compared to the Massif Central wake, the origin of the western Alps wake is rather complicated. In this study, the observations and simulations suggest a combined wall separation/gravity wave breaking mechanism to explain the western Alps wake. Indeed, it is shown that in addition to the flow descending the western Alps slopes and experiencing a strong hydraulic jump, the point where the mistral flow separates from the eastern flank of the Rhône valley located at about 44°N is associated with a 'flank-shock' which is an oblique hydraulic jump (i.e.the downstream Froude number is supercritical). Wake formation in the lee of the Alps and the Massif Central causes large inhomogeneity of the PBL with differences between land and sea. In the Massif Central and western Alps wakes, the continental PBL is deeper (1.8 km) than in the mistral flow (1 km), which is consistent with a subcritical regime associated

Parameterization of a numerical 2-D debris flow model with entrainment: a case study of the Faucon catchment, Southern French Alps

NASA Astrophysics Data System (ADS)

Hussin, H. Y.; Luna, B. Quan; van Westen, C. J.; Christen, M.; Malet, J.-P.; van Asch, Th. W. J.

2012-10-01

The occurrence of debris flows has been recorded for more than a century in the European Alps, accounting for the risk to settlements and other human infrastructure that have led to death, building damage and traffic disruptions. One of the difficulties in the quantitative hazard assessment of debris flows is estimating the run-out behavior, which includes the run-out distance and the related hazard intensities like the height and velocity of a debris flow. In addition, as observed in the French Alps, the process of entrainment of material during the run-out can be 10-50 times in volume with respect to the initially mobilized mass triggered at the source area. The entrainment process is evidently an important factor that can further determine the magnitude and intensity of debris flows. Research on numerical modeling of debris flow entrainment is still ongoing and involves some difficulties. This is partly due to our lack of knowledge of the actual process of the uptake and incorporation of material and due the effect of entrainment on the final behavior of a debris flow. Therefore, it is important to model the effects of this key erosional process on the formation of run-outs and related intensities. In this study we analyzed a debris flow with high entrainment rates that occurred in 2003 at the Faucon catchment in the Barcelonnette Basin (Southern French Alps). The historic event was back-analyzed using the Voellmy rheology and an entrainment model imbedded in the RAMMS 2-D numerical modeling software. A sensitivity analysis of the rheological and entrainment parameters was carried out and the effects of modeling with entrainment on the debris flow run-out, height and velocity were assessed.

The dilemma of gaps in carbonate stratigraphic sequences: A case history from the Jurassic of the Venetian Alps, Italy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zempolich, W.G.

The Lower Ammonitico Rosso (L.A.R.) of the western Venetian Alps is a thin, red nodular limestone that overlies a thick Late Triassic to Middle Jurassic (Aalenian) shallow-water platform sequence. It is thought to represent a Middle Jurassic (Bajocian) drowning event whereby the Trento Platform became a submerged plateau. The L.A.R. is problematic in that it (1) is rich in ammonites and other pelagic fauna; (2) contains stromatolites, oncolites, and shallow-water sedimentary structures; and (3) directly overlies platform sediments that contain complex brecciated fabrics filled by cement and Bajocian-age sediment. These seemingly contradictory features have generated much debate as to themore » sequence stratigraphy of the Trento Platform. New evidence suggests that the L.A.R. was deposited in a shallow-water environment following a period of subaerial exposure. In an east-west transect from the platform edge to platform interior, a clear transition is exhibited from high- and low-energy open-marine facies to restricted lagoonal facies. High-energy open-marine facies include well-sorted skeletal- and peloidal-rich sands possessing low-angle to planar cross stratification and thin, fairly sorted ammonite- and belemnite-rich gravels. Sands include both shallow-water and pelagic fauna; gravels commonly contain ripup clasts from underlying sediments. Low-energy open-marine facies consist of buff colored wackestones and packstones that contain ammonites, belemnites, pelagic bivalves, and peloids. With respect to paleogeography, the abrupt transition from open-marine facies at the platform edge to lagoonal facies in the platform interior indicates that thrombolites, stromatolites, and oncolites accumulated in a shallow restricted environment.« less

Forest fire weather in western Oregon and western Washington in 1957.

Treesearch

Owen P. Cramer

1957-01-01

Severity of 1957 fire weather west of the Cascade Range summit in Oregon and Washington was near the average of the previous 10 years. The season (April 1 through October 31) was slightly more severe than 1956 in western Oregon and about the same as 1956 in western Washington. Spring fire weather was near average severity in both western Washington and western Oregon....

Sensitivity to Regional Earthquake Triggering and Magnitude-Frequency Characteristics of Microseismicity Detected via Matched-Filter Analysis, Central Southern Alps, New Zealand

NASA Astrophysics Data System (ADS)

Boese, C. M.; Townend, J.; Chamberlain, C. J.; Warren-Smith, E.

2016-12-01

Microseismicity recorded since 2008 by the Southern Alps Microseismicity Borehole Array (SAMBA) and other predominantly short-period seismic networks deployed in the central Southern Alps, New Zealand, reveals distinctive patterns of triggering in response to regional seismicity (magnitudes larger than 5, epicentral distances of 100-500 km). Using matched-filter detection methods implemented in the EQcorrscan package (Chamberlain et al., in prep.), we analyze microseismicity occurring in several geographically distinct swarms in order to examine the responses of specific microearthquake sources to earthquakes of different sizes occurring at different distances and azimuths. The swarms exhibit complex responses to regional seismicity which reveal that microearthquake triggering in these cases involves a combination of extrinsic factors (related to the dynamic stresses produced by the regional earthquake) and intrinsic factors (controlled by the local state of stress and possibly by hydrogeological processes). We find also that the microearthquakes detected by individual templates have Gutenberg-Richter magnitude-frequency characteristics. Since the detected events, by design, have very similar hypocentres and focal mechanisms, the observed scaling pertains to a restricted set of fault planes.

Characterization Of Industrial And Background Aerosols In The RhÔne-alpes Region Using Laser Remote Sensing Device.

NASA Astrophysics Data System (ADS)

Geffroy, S.; Rairoux, P.; Mondelain, D.; Boutou, V.; Wolf, J.-P.; Frejafon, E.

Lack of reliable database on aerosol emission and dispersion is one of the main rea- sons for the incertitude of the impact of aerosol on the climate change. International statements and policies requested improvement on the global and on the regional scale. This new project is related to the characterisation of the spatial and time distribution of the aerosols in the Rhône-Alpes region. Actually, aerosols monitoring is mainly performed at ground level in this region and only few studies have been performed on the 3D distribution of urban aerosols (soot) using remote sensing laser device. The Rhône-Alpes region is representative for the regional impact of industry and traffic emission and also for the long-range transport of pollution over the East part of the Alps. The environmental situation of the region in term of sources and localization is especially dominated by: heavy traffic with several motorways (A6 from Paris, A7 to Marseille - both downtown - and A43 to the Alps and Italy) and industrial pollu- tion in particular for Lyon (refinery and several chemistry plants) and Saint Etienne agglomerations, which have a direct impact on the local air quality and also on the regional and national scale. Characterization of the aerosol load and dispersion in this region will be achieved applying two schemes. The first one will be related to the 3D quantitative characterization of diffuse aerosol emission in the industrial areas. Mon- itoring will be performed using a UV-infrared lidar remote sensing device. Emission cadastre elaboration and microphysical characterisation of the emission will be estab- lished. Direct access to several aerosol distribution modes will be used to describe the aerosol population dynamic: sedimentation, transport and aggregation. Studies on the direct impact of the emission on the region will be achieved coupling the 3D and ground level monitoring with dispersion model. The second scheme will be related to the long term remote sensing of

Natural hazard risk assessment and management in the Matter valley, Swiss Alps

NASA Astrophysics Data System (ADS)

Herz, T.; King, L.; Philippi, S.

2003-04-01

The Matter valley has a length of about 40 km and is surrounded by some of the highest peaks of the Alps resulting in extreme altitudinal differences and a continental character of the climate. These climatic conditions cause a high glacier equilibrium line and therefore a periglacial belt of a large vertical extend. Due to the high relief energy, all kinds of natural hazards typical for high mountain environments occur. The steep western slopes are dominated by rockfalls, slope instabilities in bedrock and avalanches. A widespread cover of unconsolidated sediments on the eastern slopes induces landslides and debris flows, which often reach down to the valley bottom where they can dam up the river. Increasing population and modern land use forms required a more and more sensitive attitude towards natural hazard potentials in this endangered area. Assessment and management of natural hazard risks have been much improved during the last fifteen years and increasing amounts of money are spent each year in order to safeguard settlements, traffic lines, and other objects of the technical infrastructure. Numerous investigations concerning natural hazard risks have been made and the results are considered in the actual land use planning of the Canton. The planning law of the Canton Valais defines risk zones as areas, which are endangered by natural hazards like avalanches, rockfalls, landslides and floodings. Risk assessment is done by overview maps (scale 1:25,000) which are specified by detailed risk analyses consisting of registers and detailed maps (scale 1:2,000 to 1:10,000). These analyses are integrated in the land zoning by defining zones of high, medium and low danger, associated with corresponding prohibitions, restrictions and conditions for utilisation. At present, the incorporation of the avalanche and rockfall register in local zoning plans is completed in most communities of the Canton Valais. An additional inventory of 200 slope instabilities was

View of Snowy Mountains area of Australian Alps as photographed from Skylab

NASA Image and Video Library

1973-07-30

SL3-27-180 (July-September 1973) --- A vertical view of the Snowy Mountains area of Australian Alps in the States of Victoria and New South Wales, Australia, as photographed from Earth orbit by one of the six lenses of the Itek-furnished S190-A Multispectral Photographic Facility Experiment aboard the Skylab space station. This picture was taken with type 2443 infrared color film. The lake near the center of the picture is the Eucumbene Reservoir. This area is located immediately south-southwest of the capital city of Canberra. Federal agencies participating with NASA on the EREP project are the Departments of Agriculture, Commerce, Interior, the Environmental Protection Agency and the Corps of Engineers. All EREP photography is available to the public through the Department of Interior?s Earth Resources Observations Systems Data Center, Sioux Falls, South Dakota, 57198. Photo credit: NASA

Post-20 Ma Motion of the Adriatic Plate: New Constraints From Surrounding Orogens and Implications for Crust-Mantle Decoupling

NASA Astrophysics Data System (ADS)

Le Breton, Eline; Handy, Mark R.; Molli, Giancarlo; Ustaszewski, Kamil

2017-12-01

A new kinematic reconstruction that incorporates estimates of post-20 Ma shortening and extension in the Apennines, Alps, Dinarides, and Sicily Channel Rift Zone (SCRZ) reveals that the Adriatic microplate (Adria) rotated counterclockwise as it subducted beneath the European Plate to the west and to the east, while indenting the Alps to the north. Minimum and maximum amounts of rotation are derived by using, respectively, estimates of crustal extension along the SCRZ (minimum of 30 km) combined with crustal shortening in the Eastern Alps (minimum of 115 km) and a maximum amount (140 km) of convergence between Adria and Moesia across the southern Dinarides and Carpatho-Balkan orogens. When combined with Neogene convergence in the Western Alps, the best fit of available structural data constrains Adria to have moved 113 km to the NW (azimuth 325°) while rotating 5 ± 3° counterclockwise relative to Europe since 20 Ma. Amounts of plate convergence predicted by our new model exceed Neogene shortening estimates of several tens of kilometers in both the Apennines and Dinarides. We attribute this difference to crust-mantle decoupling (delamination) during rollback in the Apennines and to distributed deformation related to the northward motion of the Dacia Unit between the southern Dinarides and Europe (Moesia). Neogene motion of Adria resulted from a combination of Africa pushing from the south, the Adriatic-Hellenides slab pulling to the northeast, and crustal wedging in the Western Alps, which acted as a pivot and stopped farther northwestward motion of Adria relative to Europe.

An approximate fluvial equilibrium topography for the Alps

NASA Astrophysics Data System (ADS)

Stüwe, K.; Hergarten, S.

2012-04-01

This contribution addresses the question whether the present topography of the Alps can be approximated by a fluvial equilibrium topography and whether this can be used to determine uplift rates. Based on a statistical analysis of the present topography we use a stream-power approach for erosion where the erosion rate is proportional to the square root of the catchment size for catchment sizes larger than 12 square kilometers and a logarithmic dependence to mimic slope processes at smaller catchment sizes. If we assume a homogeneous uplift rate over the entire region (block uplift), the best-fit fluvial equilibrium topography differs from the real topography by about 500 m RMS (root mean square) with a strong systematic deviation. Regions of low elevation are too high in the equilibrium topography, while high-mountain regions are too low. The RMS difference significantly decreases if a spatially variable uplift function is allowed. If a strong variation of the uplift rate on a scale of 5 km is allowed, the systematic deviation becomes rather small, and the RMS difference decreases to about 150 m. A significant part of the remaining deviation apparently arises from glacially-shaped valleys, while another part may result from prematurity of the relief (Hergarten, Wagner & Stüwe, EPSL 297:453, 2010). The best-fit uplift function can probably be used for forward or backward simulation of the landform evolution.

Climate change impacts on hydropower in the Swiss and Italian Alps.

PubMed

Gaudard, Ludovic; Romerio, Franco; Dalla Valle, Francesco; Gorret, Roberta; Maran, Stefano; Ravazzani, Giovanni; Stoffel, Markus; Volonterio, Michela

2014-09-15

This paper provides a synthesis and comparison of methodologies and results obtained in several studies devoted to the impact of climate change on hydropower. By putting into perspective various case studies, we provide a broader context and improved understanding of climate changes on energy production. We also underline the strengths and weaknesses of the approaches used as far as technical, physical and economical aspects are concerned. Although the catchments under investigation are located close to each other in geographic terms (Swiss and Italian Alps), they represent a wide variety of situations which may be affected by differing evolutions for instance in terms of annual runoff. In this study, we also differentiate between run-of-river, storage and pumping-storage power plants. By integrating and comparing various analyses carried out in the framework of the EU-FP7 ACQWA project, this paper discusses the complexity as well as current and future issues of hydropower management in the entire Alpine region. © 2013 Elsevier B.V. All rights reserved.

Biodiversity of oribatid mites (Acari: Oribatida) along an altitudinal gradient in the Central Alps.

PubMed

Fischer, Barbara M; Schatz, Heinrich

2013-01-01

Oribatid mite communities were studied in the Central Alps (Obergurgl, Tyrol, Austria). Samples were taken on four sites along an altitudinal gradient from 2050 m a.s.l to 2900 m a.s.l., in different vegetation units (pine forest, Nardetum, Caricetum, Androsacetum). A total of 86 species were found, most of them occurred only at one altitude, four species were found in all four study sites. Three taxa could not be ascribed to a certain species (Carabodes sp. Mycobates sp., Tectocepheus sp.). Species richness and density of oribatid mites decrease with increasing altitude. The results are compared with previous studies in the same region and show remarkable shifts in species composition.

Retrieval of the ultraviolet aerosol optical depth during a spring campaign in the Bavarian Alps.

PubMed

Lenoble, Jacqueline; Martin, Timothy; Blumthaler, Mario; Philipona, Rolf; Albold, Astrid; Cabot, Thierry; de La Casinière, Alain; Gröbner, Julian; Masserot, Dominique; Müller, Martin; Pichler, Thomas; Seckmeyer, Günther; Schmucki, Daniel; Touré, Mamadou Lamine; Yvon, Alexis

2002-03-20

A measurement campaign was organized in March 1999 in the Bavarian Alps as part of the European project, Characteristics of the UV Radiation Field in the Alps (CUVRA), to analyze the effect of altitude, aerosols, and snow cover on ground-level UV spectral irradiance. We present the results of simultaneous measurements of aerosol optical depth (AOD) made at various sites on two cloudless days in March 1999. The two days exhibited different aerosol conditions. Results derived from spectral measurements of UV irradiance are compared with data from filter radiometer measurements made at discrete wavelengths extending from the UV to the near IR. The different methods generated values for the AOD that were in good agreement. This result confirms that one can use either method to retrieve the AOD with an uncertainty of approximately 0.03-0.05. On 18 March, high turbidity was observed at low altitude (400-nm AOD approximately 0.5 at 700 m above sea level), and the AOD decreased regularly with altitude; on 24 March, the turbidity was much less (0.11 at 700 m above sea level). On both days very low AODs (0.05-0.09) were measured at 3000 m above sea level. The spectral dependence of the AOD is often parameterized by the angstrom relationship; the alpha parameter is generally difficult or impossible to retrieve from spectral measurements because of the relatively narrow wavelength range (320-400 nm), and only one of the spectro-radiometers used during the campaign permits this retrieval. In most cases, during this field campaign, alpha was found by filter sunphotometers to be 1.1-1.5.

Long-term snow and weather observations at Weissfluhjoch and its relation to other high-altitude observatories in the Alps

NASA Astrophysics Data System (ADS)

Marty, Christoph; Meister, Roland

2012-12-01

Snow and weather observations at Weissfluhjoch were initiated in 1936, when a research team set a snow stake and started digging snow pits on a plateau located at 2,540 m asl above Davos, Switzerland. This was the beginning of what is now the longest series of daily snow depth, new snow height and bi-monthly snow water equivalent measurements from a high-altitude research station. Our investigations reveal that the snow depth at Weissfluhjoch with regard to the evolution and inter-annual variability represents a good proxy for the entire Swiss Alps. In order to set the snow and weather observations from Weissfluhjoch in a broader context, this paper also shows some comparisons with measurements from five other high-altitude observatories in the European Alps. The results show a surprisingly uniform warming of 0.8°C during the last three decades at the six investigated mountain stations. The long-term snow measurements reveal no change in mid-winter, but decreasing trends (especially since the 1980s) for the solid precipitation ratio, snow fall, snow water equivalent and snow depth during the melt season due to a strong temperature increase of 2.5°C in the spring and summer months of the last three decades.

Diversity of bacteria producing pigmented colonies in aerosol, snow and soil samples from remote glacial areas (Antarctica, Alps and Andes)

NASA Astrophysics Data System (ADS)

González-Toril, E.; Amils, R.; Delmas, R. J.; Petit, J.-R.; Komárek, J.; Elster, J.

2008-04-01

Four different communities and one culture of pigmented microbial assemblages were obtained by incubation in mineral medium of samples collected from high elevation snow in the Alps (Mt. Blanc area) and the Andes (Nevado Illimani summit, Bolivia), from Antarctic aerosol (French station Dumont d'Urville) and a maritime Antarctic soil (King George Island, South Shetlands, Uruguay Station Artigas). Molecular analysis of more than 200 16S rRNA gene sequences showed that all cultured cells belong to the Bacteria domain. The phylogenetic comparison with the currently available rDNA database allowed the identification of sequences belonging to Proteobacteria (Alpha-, Beta- and Gamma-proteobacteria), Actinobacteria and Bacteroidetes phyla. The Andes snow culture was the richest in bacterial diversity (eight microorganisms identified) and the maritime Antarctic soil the poorest (only one). Snow samples from Col du midi (Alps) and the Andes shared the highest number of identified microorganisms (Agrobacterium, Limnobacter, Aquiflexus and two uncultured Alphaproteobacteria clones). These two sampling sites also shared four sequences with the Antarctic aerosol sample (Limnobacter, Pseudonocardia and an uncultured Alphaproteobacteria clone). The only microorganism identified in the maritime Antarctica soil (Brevundimonas sp.) was also detected in the Antarctic aerosol. The two snow samples from the Alps only shared one common microorganism. Most of the identified microorganisms have been detected previously in cold environments (Dietzia kujamenisi, Pseudonocardia Antarctica, Hydrogenophaga palleronii and Brebundimonas sp.), marine sediments (Aquiflexus balticus, Pseudomonas pseudoalkaligenes, Pseudomonas sp. and one uncultured Alphaproteobacteria), and soils and rocks (Pseudonocardia sp., Agrobactrium sp., Limnobacter sp. and two uncultured Alphaproteobacetria clones). Air current dispersal is the best model to explain the presence of very specific microorganisms, like those

Soil warming increased whole-tree water use of Pinus cembra at the treeline in the Central Tyrolean Alps

PubMed Central

Wieser, Gerhard; Grams, Thorsten E.E.; Matysssek, Rainer; Oberhuber, Walter; Gruber, Andreas

2016-01-01

The study quantified the effect of soil warming on sap flow density (Qs) of Pinus cembra at treeline in the Central Tyrolean Alps. To enhance soil temperature we installed a transparent roof construction above the forest floor around six trees. Six other trees served as controls in the absence of any manipulation. Roofing enhanced growing season mean soil temperature by 1.6, 1.3, and 1.0 °C at 5, 10, and 20 cm soil depth, respectively, while soil water availability was not affected. Sap flow density (using Granier-type thermal dissipation probes) and environmental parameters were monitored throughout three growing seasons. During the first year of treatment, no warming effect was detected on Qs. However, soil warming caused Qs to increase significantly by 11 and 19% above levels in control trees during the second and third year, respectively. This effect appeared to result from warming-induced root production, a reduction in viscosity and perhaps an increase also in root hydraulic conductivity. Hardly affected were leaf-level net CO2 uptake rate and conductance for water vapor, so that water-use efficiency stayed unchanged as confirmed by needle δ13C analysis. We conclude that tree water loss will increase with soil warming, which may alter the water balance within the treeline ecotone of the Central Austrian Alps in a future warming environment. PMID:25737326

Multi Source Remote Sensing for Monitoring Light-Absorbing Impurities on Snow and Ice in the European Alps

NASA Astrophysics Data System (ADS)

Colombo, R.; Baccolo, G.; Garzonio, R.; Massabò, D.; Julitta, T.; Rossini, M.; Ferrero, L.; Delmonte, B.; Maggi, V.; Mattavelli, M.; Panigada, C.; Cogliati, S.; Cremonese, E.; Di Mauro, B.

2016-12-01

The European Alps are located close to one of the most industrialized areas of the planet and they are 3.000 km from the largest desert of the Earth. Light-absorbing impurities (LAI) emitted from these sources can reach the Alpine chain and deposit on snow covered areas and mountain glaciers. Although several studies show that LAI have important impacts on the optical properties of snow and ice, reducing the albedo and promoting the melt, this impact has been poorly characterized in the Alps. In this contribution, we present the results of a multisource remote sensing approach aimed to study the LAI impact on snow and ice properties in the Alpine area. This process has been observed by means of remote and proximal sensing methods, using satellite (Landsat 8, Hyperion and MODIS data), field spectroscopy (ASD measurements), Automatic Weather Stations, aerial surveys (Unmanned Aerial Vehicle), radiative transfer modeling (SNICAR and TARTES) and laboratory analysis (hyperspectral imaging system). Furthermore, particle size (Coulter Counter), geochemical (Instrumental Neutron Activation Analysis, INAA) and optical (Multi-Wavelength Absorbance Analyzer, MWAA) analyses have been applied to determine the nature and radiative properties of particulate material deposited on snow and ice or aggregated into cryoconite holes. Our results demonstrate that LAI can be monitored from remote sensing at different scale. LAI showed to have a strong impact on the Alpine cryosphere, paving the way for the assessment of their role in melting processes.

Carex sempervirens tussocks induce spatial heterogeneity in litter decomposition, but not in soil properties, in a subalpine grassland in the Central Alps

Treesearch

Fei-Hai Yu; Martin Schutz; Deborah S. Page-Dumroese; Bertil O. Krusi; Jakob Schneller; Otto Wildi; Anita C. Risch

2011-01-01

Tussocks of graminoids can induce spatial heterogeneity in soil properties in dry areas with discontinuous vegetation cover, but little is known about the situation in areas with continuous vegetation and no study has tested whether tussocks can induce spatial heterogeneity in litter decomposition. In a subalpine grassland in the Central Alps where vegetation cover is...

Western Samoa.

PubMed