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131.
Prof. Dr. Konrad Günther Ass.- Prof. Dr. Eckard Wallbrecher 《International Journal of Earth Sciences》1979,68(1):172-194
Zusammenfassung Die tektonischen Einheiten der Apuaner Alpen zeigen sowohl makroskopische als auch mesoskopische axiale Gefüge mit NW-SE-Orientierung, die der apenninischen Richtung entsprechen. In den ältesten Gesteinen des autochthonen Kerns überlagert diese Richtung Relikte eines früheren linearen Systems mit bevorzugtem NE-SW-Streichen. Dieses ältere System ist auf Phyllitserien beschränkt, welche in Marmorlagen paläozoische Faunen führen (VAI 1972). Sein Entstehungsalter muß demnach präalpidisch sein.Während der Hauptorogenese des Nordapennins erfolgte die stärkste Einengung und der tektonische Transport in SW-NE-Richtung. Dabei wurde die Zone von Massa von SW her auf den internen Teil des Autochthons aufgeschoben und gleichzeitig in ihr ein lineares System mit apenninischer Streichrichtung erzeugt. Das präalpidische Axial-System wurde um die apenninische Richtung rotiert und es entstanden Lineare mit steilerem Einfallen und einer charakteristischen Verteilung auf einem steilen Teilgürtel im Gefügediagramm. Die Platznahme der parautochthonen Schuppen (Campo Cecina, Isola Santa und Stazzema) erfolgte zur gleichen Zeit. Ihr Herkunftsgebiet kann die Zone von Massa gewesen sein.Die Schieferungsflächen des Autochthons wurden, entsprechend der stress-Verteilung, ursprünglich mit einer SW-Vergenz angelegt. Im Verlauf der Orogenese rotierten sie, parallel zu B, in eine steilere Lage. Schließlich entstanden NE-vergente Foliationen mit tautozonaler Anordnung zu B, die offenbar durch die Überschiebung der Toskanischen Decke nach NE erzeugt wurden. Die schwache Faltung und die (Ton-)Schieferung in den inkompetenten Horizonten dieser Decke zeigen dieselbe stress-Verteilung.
In macroscopic and mesoscopic scale the entire Apuane Alps (allochthonous and autochthonous parts) show an axial pattern with NW-SE orientation which is conform to the Apenninic direction. In the oldest layers of the center of the autochthonous core, this direction superimposes remnants of an older linear system with a preferred NE-SW direction. This system is limited to schists which contain palaeozoic layers (VAI 1972). Its age, therefore, must be pre-Alpidic.During the orogenesis of the Apennine mountain chain the direction of the main pressure was SW-NE. This caused an upthrusting of the Massa Zone on the autochthonous part with movements in NE direction. The Apennine direction of fold axes was then established in the Massa Zone. The pre-Alpidic system of linears was rotated around the Apennine direction and linears with a steeper plunge and a characteristic steep girdle distribution originated. The emplacement of the parautochthonous schuppen zones of Campo Cecina, Isola Santa and Stazzema took place in the same time; the Massa Zone might even be the origin of these thrust slices.The schistosity planes in the autochthonous part generated with a primary SW vergence (sf1-planes parallel to B-axes which also show a NW orientation) according to the distribution of stress. In the course of orogenesis the schistosity planes rotated into steeper positions, still parallel to B. Finally, probably together with the movement of the Tuscan nappe towards the NE, the foliation systems tautozonal to B with vergences into NE direction resulted which now predominate. The weak folding and the slaty cleavage system in the Tuscan nappe reproduces the same pattern of stress distribution.it]Riassunto In scala macro e mesoscopica tutte le parti alloctone (falda toscana), parautoctone (zona di Massa, zone a scaglie di Stazzema, Isola Santa e Campo Cecina, unità delle Panie) e autoctone (autoctono Apuano) mostrano una distribuzione assiale orientata in direzione NW-SE, che corrisponde alla direzione generale dell'Appennino settentrionale. Nelle formazioni più antiche (Paleozoico) del nucleo autoctono, questa direzione è sovrapposta a relitti di un sistema precedente con direzione predominante NE-SW. Questo sistema si riconosce su filladi quarzifere e scisti sericitico-cloritici, che contengono una fauna paleozoica in dolomie e marmi intercalati (Vai 1972); la sua età quindi deve considerarsi prealpidica.Durante l'orogenesi principale dell'Appennino settentrionale la pressione maggiore, dovuta al trasporto tettonico, si manifestava in direzione SW-NE. Con questo movimento si verifica un accavallamento verso NE della zona di Massa sulla parte interna dell'autoctono. Contemporaneamente in quest'unità parautoctona si originava un sistema di lineazioni in direzione appenninica. Il sistema assiale prealpidico è stato poi rotato in conseguenza della nuova tettogenesi appenninica. Con questa rotazione si generavano lineazioni con un'inclinazione maggiore ed una distribuzione caratteristica a cintura sul reticolo diSchmidt. Contemporaneamente le zone parautoctone a scaglie di Stazzema, Isola Santa e Campo Cecina sono state spostate sul nucleo autoctono. La loro zona di origine potrebbe essere stata la stessa dell'unità parautoctona di Massa.I piani di scistosità dell'autoctono si formavano secondo la distribuzione dello stress — dapprima con una vergenza verso SW (sf1-piani paralleli all'asse B delle pieghe con direzione NW-SE). Durante l'orogenesi questi piani ruotavano — sempre paralleli a B — in una posizione a maggiore inclinazione e finalmente originavano foliazioni (sf2) con una vergenza verso NE, che mostrano una distribuzione tautozonale con B. Queste foliazioni che probabilmente si sono formate durante il movimento della falda toscana verso NE ora predominano nell'assetto tettonico.Il debole piegamento e la scistosità di tipo slaty cleavage negli orizzonti incompetenti della falda toscana mostrano la stessa distribuzione di stress in un piano tettonico superiore a quello dell'autoctono e parautoctono.
Résumé Les unités tectoniques des Alpes Apuanes montrent une orientation axiale correspondant à la direction apennine. Cette direction interfère à la base du socle autochtone avec un système linéaire, d'orientation préférentielle NE-SW. Ce système plus ancien est limité aux séries de phyllites contenant des faunes paléozoiques (VAI 1972). En conséquence, l'âge de ce système doit être pré-alpin.Pendant l'orogénèse principale de l'Apennin septentrional, le retrécissement le plus prononcé et le transport tectonique se produisicent dans la direction SW-NE. Ainsi, la zone de Massa fut superposée, venant du SW, à la partie interne de l'autochtone et affectée simultanément par un système linéaire apennin. Ensuite, le système axial pré-alpin a subi une rotation autour des axes apennins, d'où résultèrent des systèmes linéaires à fort plongement et une distribution caractéristique des axes plus raides. La mise en place des écailles parautochthones, dont l'origine pourrait être la zone de Massa, se réalisa en même temps.D'abord les surfaces de schistosité dans l'autochtone ont été déversées vers le SW, à cause de la distribution tensionelle. Au cours de l'orogénèse, elles ont subi une rotation, parallèlement à B, dans une position à plongement plus fort. Finalement résultèrent des foliations déversées vers le NE, qui ont été formées par le transport vers le NE de la nappe toscane.Le faible plissement et le clivage dans cette nappe montrent la même distribution de tension.
, , — - , . -. , (VAi 1972). , -. . - , . - .. . ( , ). Macca. — — - (sf, — «B», -). «» . , , -, , «B» - , . - .相似文献
132.
Erin M. Barley Ian R. Walker Joshua Kurek Les C. Cwynar Rolf W. Mathewes Konrad Gajewski Bruce P. Finney 《Journal of Paleolimnology》2006,36(3):295-314
Freshwater midges, consisting of Chironomidae, Chaoboridae and Ceratopogonidae, were assessed as a biological proxy for palaeoclimate in eastern Beringia. The northwest North American training set consists of midge assemblages and data for 17 environmental variables collected from 145 lakes in Alaska, British Columbia, Yukon, Northwest Territories, and the Canadian Arctic Islands. Canonical correspondence analyses (CCA) revealed that mean July air temperature, lake depth, arctic tundra vegetation, alpine tundra vegetation, pH, dissolved organic carbon, lichen woodland vegetation and surface area contributed significantly to explaining midge distribution. Weighted averaging partial least squares (WA-PLS) was used to develop midge inference models for mean July air temperature (r
boot2 = 0.818, RMSEP = 1.46°C), and transformed depth (ln (x+1); r
boot2 = 0.38, and RMSEP = 0.58). 相似文献
133.
Konrad Cehak 《Meteorology and Atmospheric Physics》1956,9(4):487-513
Zusammenfassung Die statistische Untersuchung mittels des 2-Tests über den Zusammenhang zwischen Gewittertätigkeit und Sonnenaktivität und die Realität desselben führt zu dem Ergebnis, daß nur in 40,9% der betrachteten Stationen mit großer Wahrscheinlichkeit auf einen Zusammenhang geschlossen werden darf. Diese Stationen umfassen vor allem Berg- und Küstenstationen, daher scheint ein Zusammenhang—wenn überhaupt—dann für Wärme- und orographische Gewitter zu bestehen und zwar vor allem in den Tropen und Gebieten nördlich von 55°N. Dabei fallen die Extremwerte der verschiedenen Stationen in ganz verschiedene Jahre innerhalb des Fleckenzyklus, was durchaus kein Argument für einen reellen Zusammenhang der beiden Phänomene ist.Betrachtungen einer 26 tägigen Periode zeigen, daß wohl einige Tage dieser Periode besonders gewitterreich oder gewitterarm sind, doch schwanken die Vorzeichen der Abweichungen vom Mittelwert ziemlich unregelmäßig. Da außerdem eine Ähnlichkeit zwischen den Gängen in den einzelnen Stationen nicht besteht, dürfte die Periode nicht reell sein. Die Betrachtung der säkularen Änderung der Gewitterhäufigkeiten zeigt, daß die Gewittertätigkeit im großen und ganzen zunahm. Die starke Zunahme vor der Jahrhundertwende kann wohl durch genauere Beobachtung erklärt werden. Im letzten Jahrzehnt ist ein Rückgang der Gewittertätigkeit in Europa festzustellen.Aus Vergleichen mit den Resultaten früherer Untersuchungen über dasselbe Thema geht hervor, daß die kurzen Beobachtungsreihen und das Fehlen statistischer Realitätsprüfungsmethoden die betreffenden Autoren zu Schlüssen veranlaßten, die sich bei Verlängerung der Beobachtungsreihen nicht aufrechterhalten ließen. Besonders die behaupteten kurzen Perioden heilten den statistischen Kriterien nicht stand.
Mit 3 Textabbildungen 相似文献
Summary A statistical investigation carried out by the 2-test on the relation between thunderstorm activity and solar activity, and its reality, leads to the result that such a relation can be concluded with high probability in only 40,9 per cent of the considered stations being predominantly mountain and coastal stations. Therefore, a relation—if there is any at all—seems to exist for thermic and orographic thunderstorms, and particularly in the tropics and in the regions north of 55° N. The extreme values of different stations were found in quite different years of the sunspot cycle which is by no means an argument for a real relation of the two phenomena.Considerations of a 26 day period show that some days of the period are either especially rich or poor in thunderstorms, the signs of deviations from the mean value, however, vary rather irregularly. Moreover, as there is no similarity between the records of different stations the period does not seem to be a real one. The study of the secular variation of thunderstorm frequencies shows a general increase of thunderstorm activity. The strong increase at the end of the last century may be explained by better observations, though. During the last decade, a decrease of thunderstorm activity in Europe was found.Comparisons with results of former investigations on the same problem reveal that the short series of observations and the lack of statistical test of reality led authors to conclusions which could not be maintained any more when the series of observations were extended. In particular, the alleged short periods did not hold when tested by statistical criterions.
Résumé L'étude statistique au moyen du test 2 de la relation entre l'activité orageuse et celle des taches solaires montre que le 40,9% seulement des stations considérées fournit une grande probabilité de l'existence d'une telle relation. Il s'agit surtout de stations de montagne et de littoral, de sorte que le relation—si elle existe—concernerait apparemment les orages locaux et de littoral, cela surtout sous les tropiques et dans les régions situées au Nord du 55ème parallèle N. Toutefois les valeurs extrêmes des différentes stations apparaissent dans des années différentes du cycle des taches solaires, ce qui n'est pas un argument en faveur d'une relation réelle entre les deux phénomènes.En ce qui concerne une périodicité de 26 jours, il y a bien certains jours dans cette période plus riches et d'autres plus pauvres en orages, mais les écarts par rapport à la moyenne sont assez irréguliers. Et comme de plus il n'y a pas d'analogie entre les courbes de fréquence des différentes stations, cette période ne semble pas être réelle. Du point de vue de la variation séculaire, l'activité organeuse a augmenté dans l'ensemble. Le fort accroissement de fréquence à la fin du siècle passé peut s'expliquer par des observations meilleures à ce moment là. Pendant la dernière décade, l'activité orageuse en Europe a diminué.Des comparaisons avec des recherches antérieures sur le même sujet montrent que des séries trop courtes d'observations et l'absence de tests statistiques ont parfois conduit les auteurs à des conclusions que la prolongation des séries ne permet pas de maintenir. Les prétendues périodes courtes en particulier sont réduites à néant par les critères statistiques.
Mit 3 Textabbildungen 相似文献
134.
135.
Jonas V. Müller Christian Berg Jacqueline Détraz-Méroz Brigitta Erschbamer Noémie Fort Catherine Lambelet-Haueter Vera Margreiter Florian Mombrial Andrea Mondoni Konrad Pagitz Francesco Porro Graziano Rossi Patrick Schwager Elinor Breman 《山地科学学报》2017,14(4):806-810
Safeguarding plants as seeds in ex situ collections is a cost effective element in an integrated plant conservation approach. The European Alps are a regional centre of plant diversity. Six institutions have established a regional network covering the European Alps which will conserve at least 500 priority plant species and which will improve the conservation status of plant species in grassland communities in the subalpine, alpine and nival altitudinal belts. Targeted research will expand the knowledge of the ecology of target species. Public engagement activities will raise the awareness for the importance of specific conservation actions in the European Alps. 相似文献
136.
About 1 mg/g dw Cu2+ and 8 mg/g dw Fe2+ were found in roots of reed plants when fed with heavy metal concentrations of 100 μM Cu2+ and 10 mM Fe2+ under hypoxia. Roots seemed to act as a kind of filter since the amounts in rhizomes were only 0.06 mg Cu2+/g dw and 2 mg Fe2+/g dw. Increased contents of both ions reduced posthypoxic respiration capacity by 40–50% and also the sum of adenylates (ATP, ADP, AMP) by the same order of magnitude, although energy charge values remained above 0.85 in Cu2+ and 0.79 in Fe2+ treatments. Energy metabolism of rhizomes was not affected. Copper and iron contents of roots as well as of rhizomes were high enough to induce oxidative stress when roots were fed with 40 μM Cu2+ and 1 mM Fe2+, respectively.From our results we conclude that increased, but environmentally attainable, amounts of copper and reduced iron ions disturb root energy metabolism, and therefore root functioning and development. Latent injuries, based on oxidative stress, may be harmful for roots and rhizomes under long term exposure. 相似文献
137.
Joris Gerssen Konrad Kuijken Michael R. Merrifield 《Monthly notices of the Royal Astronomical Society》2000,317(3):545-549
Various processes have been proposed to explain how galaxy discs acquire their thickness. A simple diagnostic for ascertaining this 'heating' mechanism is provided by the ratio of the vertical to radial velocity dispersion components. In a previous paper we have developed a technique for measuring this ratio, and demonstrated its viability on the Sb system NGC 488. Here we present follow-up observations of the morphologically similar Sab galaxy NGC 2985, still only the second galaxy for which this ratio has been determined outside the solar neighbourhood. The result is consistent with simple disc-heating models that predict ratios of σ z σ R less than one. 相似文献
138.
Konrad Schindler Andreas Ess Bastian Leibe Luc Van Gool 《ISPRS Journal of Photogrammetry and Remote Sensing》2010,65(6):523-537
We report on a stereo system for 3D detection and tracking of pedestrians in urban traffic scenes. The system is built around a probabilistic environment model which fuses evidence from dense 3D reconstruction and image-based pedestrian detection into a consistent interpretation of the observed scene, and a multi-hypothesis tracker to reconstruct the pedestrians’ trajectories in 3D coordinates over time. Experiments on real stereo sequences recorded in busy inner-city scenarios are presented, in which the system achieves promising results. 相似文献
139.
140.
Wang BS Goodkin NF Angeline N Switzer AD You CF Hughen K 《Marine pollution bulletin》2011,63(5-12):508-515
A 182-year long record of trace metal concentrations of aluminum, zinc and lead was reconstructed from a massive Porites coral skeleton from southeastern Hong Kong to evaluate the impacts of anthropogenic activity on the marine environment. Zn/Ca and Pb/Ca ratios fluctuate synchronously from the early 19th century to the present, indicating that the marine environment has been anthropogenically influenced since industrialization. Additionally, land reclamation, mining, and ship building activities are recorded by elevated Al/Ca ratios from 1900 to 1950. The coral record indicates that high levels of Zn, Pb and Al occur coincidentally with local wars, and may have contributed to partial colony mortality. Pb/Ca does not correlate well with hemispheric proxy records after 1950, indicating that coastal corals may be recording local rather than hemispheric contamination. Pb/Ca levels in Hong Kong, Guangdong and Hainan corals imply a continuous supply of Pb-based contamination to southern China not reflected in hemispheric signals. 相似文献