Early Paleozoic rifting and bimodal volcanism in the Ossa-Morena Zone of south-west Spain     

Uwe Giese  Bernhard Bühn 《International Journal of Earth Sciences》1994,83(1):143-160

Lower Paleozoic volcanic members have been investigated by geological, petrographical and geochemical means in a traverse across the Ossa-Morena Zone (OMZ) in south-west Spain.The volcanism lasted from the Early Cambrian to the Early Ordovician, with a peak in the Middle Cambrian. The volcanism is bimodal, starting up with acidic and ending with basic compositions. From north to south, peralkaline rhyolites change to rhyolites, and strongly enriched alkali basalts change via transitional basalts to mid-ocean ridge basalt (MORB-type basalts). The geological and magmatic evolution suggests an extensive Early Paleozoic rifting with its center along the southern boundary of the OMZ. Temporal, spatial and crustal aspects of the rifting event are presented in a geodynamic model.  相似文献   

Chemical mechanisms in the dissolution kinetics of minerals; the aspect of active sites     

Bernhard Wehrli  Erich Wieland  Gerhard Furrer 《Aquatic Sciences - Research Across Boundaries》1990,52(1):3-31

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Book review     

David Gubbins  Emile A. Okal  Roberto Scarpa  R. E. Anderson  Leszek Czechowski  Rodney W. Page  Bernhard Spörli  Magdalena Kądziałko-Hofmokl  J. A. Majorowicz  Gregory Houseman  Donald L. Turcotte  David F. McTigue  Teng-fong Wong  David Lockner  David V. Wiltschko  David M. Fountain  G. P. Glasby  R. J. Angel  S. J. Gibowicz  Jonathan Franzen  Kacper R. Rybicki  Brian Farrell  Anil Suri  Zbigniew W. Kundzewicz  Witold G. Strupczewski 《Pure and Applied Geophysics》1988,127(4):695-752

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Turbulence and diffusion over inhomogeneous terrain     

N. E. Busch  S. E. Gryning  N. O. Jensen  I. Troen 《Boundary-Layer Meteorology》1987,41(1-4):173-202

This paper provides an overview of some aspects of atmospheric boundary-layer dispersion processes over homogeneous and complex terrain. Special emphasis is placed on a discussion of the boundarylayer scaling regimes over homogeneous terrain and the characteristics of the dispersion processes associated with each of these regimes. The paper points out that vertical concentration profiles usually deviate substantially from a Gaussian distribution. The mean flow and turbulence over a low hill is dealt with, and in the inner layer the turbulence levels are increased due to the mean flow speed-up. In the outer layer the turbulence is modified by the rapid distortion effect. In a middle layer the turbulence is reduced due to the effect of a hill-induced streamline curvature. The paper concludes that the flow perturbations introduced by large-scale hills and valleys invalidate the use of simple approximations for describing atmospheric dispersion processes, and that it is necessary to utilize the full set of equations of motion.  相似文献   

Helsinki —aspects of urban development and planning     

Dr. Bernhard Butzin 《GeoJournal》1978,2(1):11-26

Within a typical process of urbanization several particularities can be noticed in the Helsinki region: The peninsular location does not allow a zonal expansion of the city. It has rather enforced a tight spatial sectoral expansion with specific problems of traffic and land use. The retarded industrialization has led to an unusually fast population increase without control until the 1960s. The rapid growth created a twofold problem: pressure of population versus inadequate housing, small residences versus high rents; consequently selective migration and small size families. The number of jobs rapidly increased and displaced the residential population of the inner city. This resulted in high traffic which neither the few main roads nor the public transport system of central Helsinki could cope with. These problems correspond to the essential tasks of urban planning: the bottle neck in housing construction has to be broken; the growth of jobs in the central city needs to be stopped as well as the displacement of the residential population. Decentralization, especially of the private tertiary and quartary sector may help. A system of central places within the region would diminish the commuting traffic. Transportation may be solved by a concept of growth points and growth axis along the railway lines. This grown concept of Helsinki should be thought over under the now foreseeable conditions of population stagnation.  相似文献   

The structure of the subpolar inversion-capped ABL     

Dipl. Met. N. Busch  Dipl. Met. U. Ebel  Prof. Dr. H. Kraus  Dr. E. Schaller 《Meteorology and Atmospheric Physics》1982,31(1-2):1-18

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Book reviews     

Giulio P. Genoni  Bernhard Wehrli 《Aquatic Sciences - Research Across Boundaries》1989,51(4):370-371

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Neuartige Meßverfahren zur Erfassung von Niederschlägen     

Dr.-Ing. Bernhard Schwarz 《Theoretical and Applied Climatology》1973,21(2-3):269-285

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Dry melting of muscovite+quartz in the range P s=7 kb to P s=20 kb     

Bernhard Storre 《Contributions to Mineralogy and Petrology》1972,37(1):87-89

Experimental data obtained for dry melting of muscovite + quartz show that the stability field of this assemblage is extended to higher temperatures compared with the corresponding melting reactions with excess vapor which have been determined by Storre and Karotke (1971, 1972).  相似文献   

Boreale Einflüsse im Oberjura Westeuropas?     

Doz. Dr. Bernhard Ziegler 《International Journal of Earth Sciences》1964,54(1):250-261

Zusammenfassung Die allmähliche Abnahme der Formen-Mannigfaltigkeit gegen Norden deutet ebenso wie die Nordgrenze des Vorkommens von Riff-Korallen, Diceraten, Nerineen und Oppelien auf Unterschiede in der Meeres-Temperatur. Einer südlichen tropischen Region steht eine gemä\igte (boreale) Zone im Norden gegenüber. Nordwesteuropa liegt im übergangsbereich.Während des Oberjura ist keine allgemeine änderung der Meeres-Temperaturen nachweisbar. Die faziellen und faunistischen Besonderheiten im Mittel- und Obermalm Nordwesteuropas lassen sich am besten durch eine Verlagerung von Meeres-Strömungen erklären.

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Summary In the Upper Jurassic of Europe there is a northern boundary in the distribution of reef-corals, Diceratids, Nerineids, and Oppeliids. This feature and the greater number of species and genera in southern regions than in the North points to differences in the temperature of the Sea. It is possible to separate a southern tropical region from a temperate (boreal) zone in the North. Northwestern Europe is situated in between.During the Upper Jurassic no general change in the temperature of the sea can be observed. Peculiarities in facies and fauna of the northwestern European Upper Jurassic are well explained by displacements of currents in the Sea.

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Résumé Dans le Jurassique supérieur de l'Europe une région tropicale méridionale peut Être séparée d'une zone (« boreale ») tempérée dans le Nord. L'Europe du nord-ouest est située dans le domaine transitaire. Pendant le Jurassique supérieur aucun changement de la température de la mer est à constater. Les particuliarités du facies et de la faune dans le Malm moyen et supérieur de l'Europe du nord-ouest sont très facilement à expliquer par un déplacement de courrents dans la mer.

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Für wertvolle Hinweise danke ich Dr. K. W.Barthel (München), Dr. O. F.Geyer (Stuttgart), Prof. Dr. E.Kuhn-Schnyder und Dr. H.Rieber (beide Zürich).  相似文献