Os isotope geochemistry of mantle peridotites from Sal Island, Cape Verde Archipelago     

G. E. Brügmann  I. D. Ryabchikov  L. N. Kogarko 《Doklady Earth Sciences》2008,419(1):325-328

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The agglomeration of the GDR capital,Berlin : A survey of its economic geography     

A. Zimm Dr.  J. Bräuniger Dr. 《GeoJournal》1984,8(1):23-31

The Berlin capital agglomeration is characterized by the specific functions of its core and its agglomeration field. While the influence of historical development is still apparent, the socialist period has seen major changes in the structure of the agglomeration and in the relationship between its various subregions.Also known as East-Berlin  相似文献   

Collision and stress trajectories in Taiwan: a finite element model   总被引：2，自引：0，他引：2  

Philippe Huchon  Eric Barrier  Jean-Claude de Bremaecker  Jacques Angelier 《Tectonophysics》1986,125(1-3)

Field analyses of Plio-Quaternary compressional deformations in Taiwan have enabled us to reconstruct the paleostress trajectories resulting from the collision of the Luzon arc (Philippine Sea plate) with the Chinese continental margin (Eurasian plate). The direction of the maximum compressional stress σ₁ shows a fan-shaped pattern that we interpret as resulting from the collision of a rigid body (the Luzon arc) indenting a more deformable material (the thick sediments of the Chinese continental margin). Simple analytical models qualitatively explain the fan-shaped pattern, but the influence of various parameters such as boundary conditions and rheology cannot be quantitatively accounted for by this approach. Consequently, we have used a finite element technique to compute the stresses and strains induced by the push of a rigid body against a two-dimensional, viscous material. The boundary conditions are the velocities based on plate kinematics. A motion in the N300°E direction best explains the stress trajectories observed in central Taiwan. Viscosity contrasts as well as small changes in the shape of the northern edge of the indenter have little influence on the computed stress pattern. The most important parameter is the direction of convergence. Our model quantitatively explains the general pattern of the stress trajectories observed in the collision zone of Taiwan, between the Philippine Sea plate and Eurasia.  相似文献   

Paleomagnetic implications on the evolution of the tethys belt from the atlantic ocean to the pamirs since the triassic     

Michel Westphal  Mikhail L. Bazhenov  Jean Paul Lauer  Diamar M. Pechersky  Jean-Claude Sibuet 《Tectonophysics》1986,123(1-4)

We first re-examined the apparent polar wander curves for stable Eurasia and Africa since the Triassic. These curves were then combined together with curves of North and South America according to the kinematics of the Atlantic ocean and a synthetic polar wander curve was given. Then, most of the paleomagnetic results from the Tethys mobile belt, from the Atlantic to the Pamirs, were analysed.Several groups of plates, microplates and blocks can be seen. First, relatively stable regions like Maghreb and Sicily, which have not moved much. Then we have a group formed by Iberia, Sardinia, Italy and, to a lesser extent, Corsica and the Western and Central Alps. For these blocks, movements are anticlockwise rotations chiefly driven by the anticlockwise rotation of Africa, but they are sometimes stronger.To the east, a major change takes place. The north of the Aegean Sea and the Ionian zone are clockwise rotated and these rotations are recent: Oligocene-Miocene for the first part, Pliocene to the present for the second part.A major problem arises in Turkey, Caucasus and Iran. Paleomagnetic results indicate a position far to the south of Eurasia, and, at the same time, geological evidence is in favour of a position close to Eurasia. We discuss these discrepancies.  相似文献   

    

Jean-Claude André  Christian Blondin 《Boundary-Layer Meteorology》1987,39(4):419

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The rheology of spacially continuous mass creep in rock     

E. Brückl  A. E. Scheidegger 《Rock Mechanics and Rock Engineering》1972,4(4):237-250

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Eine Methode zur Volumbestimmung von Gletschern auf Grund der Plastizitätstheorie     

Dr. Ewald Brückl 《Meteorology and Atmospheric Physics》1970,19(1):317-328

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Advantages and disadvantages of the urban heat island —an evaluation according to the hygro-thennic Effects     

Bründl  W.  Höppe  P. 《Theoretical and Applied Climatology》1984,35(1-2):55-66

Theoretical and Applied Climatology - From data at two measuring sites of the research project ”Stadtklima Bayern“ the problems of a comparative evaluation of the bioclimate in the...  相似文献   

Characteristics and mode of emplacement of gneiss domes and plutonic domes in central-eastern Pyrenees   总被引：1，自引：0，他引：1  

Jean-Claude Soula 《Journal of Structural Geology》1982,4(3):313-342

Gneiss domes and plutonic granitoid domes make up almost 50% of the pre-Hercynian terrains in the Central and Eastern Pyrenees. From a structural study of the shape and internal structure of the domes and of their relationships with the enclosing rocks, it can be shown that both types of domes were emplaced diapirically during the major regional deformation phase and the peak of regional metamorphism.The study also shows that the internal structure, the overall shape and general behaviour relative to the host rocks are similar for plutonic domes and for gneiss domes. This appears to be in good agreement with H. Ramberg's (1967, Gravity Deformation and the Earth's Crust. Academic Press, London; 1970, Model studies in relation to intrusion of plutonic bodies. In: Mechanisms of Igneous Intrusion (edited by Newall, G. & Rast, N.) Geol. J. Spec. Issue2, 261–286.) model studies showing that dome or mushroom-like structures, similar to those observed, develop when there is a small viscosity ratio between the rising body and its enclosing medium.This implies a high crystal content for the granitoid magma. This crystal content has been estimated by (i) calculating the viscosity and density in natural conditions from petrological data for the magma considered as a suspension, using the model and program of J. P. Carron et al. (1978 Bull Soc. géol. Fr.20, 739–744.); (ii) using the recent results of experimental deformation of partially melted granites of I. van der Molen & M. S. Paterson (1979, Contr. Miner. Petrol.70, 299–318.) and (ii) comparing the preceding results with the data obtained by deformation experiments on rocks similar to those enclosing the domes. The minimum crystal content for the development of a dome-like structure has been, thus, estimated to about 70%, i.e. a value very close to that estimated by van der Molen & Paterson (1979) to be the critical value separating the granular framework flow from suspension-like behaviour.The effect of small variations in the viscosity of the rising body are then simulated by centrifuge experiments. These small variations appear to exert a strong control on the shape and rate of rise of the domes. They are thought to be sufficient to account for the variations in shape and structure and the level of emplacement of the different types of gneissic and plutonic domes.Finally, more complex experiments, with models built in order to simulate as closely as possible the natural structural evolution of the region as deduced from petrological and structural data, are reported. Their implications for the regional interpretation of the relationships between gneissic and plutonic domes is then discussed.  相似文献   

A fast approximate method for the calculation of the infrared radiation balance within city street cavities     

Prof. Dr. W. Zdunkowski  Ch. Brühl 《Theoretical and Applied Climatology》1983,33(3):237-241

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