Miscible transfer of solute in different model fractures: From random to multiscale wall roughness     

Harold Auradou  Alejandro Boschan  Ricardo Chertcoff  Maria-Veronica D’Angelo  Jean-Pierre Hulin  Irene Ippolito 《Comptes Rendus Geoscience》2010,342(7-8):644-652

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Geo-Characterization at selected accelerometric stations in Crete (Greece) and comparison of earthquake data recordings with EC8 elastic spectra   总被引：1，自引：0，他引：1  

A. Savvaidis  B. Margaris  N. Theodoulidis  V. Lekidis  Ch. Karakostas  C. Loupasakis  D. Rozos  P. Soupios  M. -D. Mangriotis  U. Dikmen  Par. Tsangaratos  E. Kokinou  A. Vafidis  Th. Rondoyanni  I. Kalogeras  S. Koutrakis  A. Sarris  N. Papadopoulos 《Central European Journal of Geosciences》2014,6(1):88-103

To estimate the seismic response according to Eurocode (EC8) and almost all other national codes, site conditions have to be properly characterized so that soil amplification and the corresponding peak ground motion can be calculated. In this work, different geophysical and geotechnical methods are combined in order to define the detailed ground conditions in selected sites of the Hellenic Accelerometric Network (HAN) in Crete. For this purpose, the geological information of the sites and shear wave velocity, calculated from surface wave measurements, is used. Additionally, ground acceleration data recorded through HAN have been utilized from intermediate depth earthquakes in the broader area of South Aegean Sea. Using the recorded ground motion data and the procedure defined in EC8, the corresponding elastic response spectrum is calculated for the selected sites. The resulting information is compared to the values defined in the corresponding EC8 spectrum for the seismic zone that includes the island of Crete. The comparison shows that accurate definition of ground type through geological, geotechnical and geophysical investigations is important. However, our current comparison focuses on the distribution of values rather than the absolute values of EC8-prescribed spectra, and the results should be considered in this context.  相似文献   

Strong, Variable Circular Polarization in PKS 1519–273     

Jean-Pierre Macquart  Lucyna Kedziora-Chudczer  David Jauncey  David Rayner 《Astrophysics and Space Science》2001,277(1-2):135-138

It is found that velocity shear enables the extraction of kinetic energy from the background flow by Dust-Acoustic waves. It is also shown that the velocity shear leads to the appearance of a new mode of the dust particles collective behaviour, called shear dust vortices. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

Multiple mantle sources during island arc magmatism: U–Pb and Hf isotopic evidence from the Kohistan arc complex, Pakistan     

Urs Schaltegger  Gerold Zeilinger  Martin Frank  Jean-Pierre Burg 《地学学报》2002,14(6):461-468

ABSTRACT This paper presents high-precision U–Pb ages and initial Hf isotopic compositions of zircon from mafic to felsic rocks of the Kohistan Arc Complex, Pakistan. Three magmatic pulses tapping geochemically different reservoirs are distinguished. Partial melting of mantle with MORB-type isotopic characteristics generated 99–92-Ma-old magmas. Plutonism around 85 Ma tapped a more fertile mantle source, most likely consisting of a >600-Ma-old metasomatically enriched mantle, or of mantle contaminated by an old sedimentary component; 82-Ma-old felsic peraluminous dykes have MORB-type isotopic compositions considered to be inherited from remelting earlier magmas in the deep base of the arc. The isotopic results demonstrate several and rather rapid changes in melt source region during arc development. They also show that there was subordinate continental influence and negligible importance of slab components for the Hf budget during the generation of the Kohistan Arc Complex.  相似文献   

Low-temperature constraints on the Cenozoic thermal evolution of the Southern Rhodope Core Complex (Northern Greece)     

Alexandre Kounov  Eliane Wüthrich  Diane Seward  Jean-Pierre Burg  Daniel Stockli 《International Journal of Earth Sciences》2015,104(5):1337-1352

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On the Multiplicity of the O-Star Cyg OB2 #8a and its Contribution to the γ-ray Source 3EG J2033+4118     

Michael De Becker  Gregor Rauw  Jean-Pierre Swings 《Astrophysics and Space Science》2005,297(1-4):291-298

We present the results of an intensive spectroscopic campaign in the optical waveband revealing that Cyg OB2 #8A is an O6+O5.5 binary system with a period of about 21.9 days. Cyg OB2 #8A is a bright X-ray source, as well as a non-thermal radio emitter. We discuss the binarity of this star in the framework of a campaign devoted to the study of non-thermal emitters, from the radio waveband to γ-rays. In this context, we attribute the non-thermal radio emission from this star to a population of relativistic electrons, accelerated by the shock of the wind-wind collision. These relativistic electrons could also be responsible for a putative γ-ray emission through inverse Compton scattering of photospheric UV photons, thus contributing to the yet unidentified EGRET source 3EG J2033+4118. Based partly on data Obtained at the Observatoire de Haute-Provence, France.  相似文献   

Syn-metamorphic nappe complex in the Rhodope Massif. Structure and kinematics     

Jean-Pierre Burg  Luc-Emmanuel Ricou  Zivko Ivano  Ivan Godfriaux  Dimo Dimov  Laslo Klain 《地学学报》1996,8(1):6-15

Mylonitic gneisses of the Bulgarian and Greek Rhodope were deformed under medium pressure-type metamorphism. The kinematic information contained in these gneisses shows that shear-deformation occurred during development of a nappe complex. Lithologies and metamorphic histories allow a lower (footwall) and an upper (hanging wall) terrane to be distinguished that define a crustal-scale duplex. As oceanic crust is involved, collision between two continental units with subsequent crustal thickening is inferred. The blocks would be Moesia to the north, and the Lower-Rhodope promontory to the south, which collided in the Mesozoic to early Cenozoic. The nappe complex is characterized by south to southwestward (foreland directed) piling-up and is associated with both coeval and subsequent extension. The late extension is associated with the establishment of a high temperature-low pressure metamorphic gradient and plutonism that predates, but makes a transition to, the lithospheric extension of the Aegean Arc.  相似文献   

Paul Ledoux     

Jean-Pierre Swings 《Astrophysics and Space Science》1989,155(2):iv-180

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Événements panafricains dans l'Adrar Souttouf (Sahara marocain)     

Michel Villeneuve  Hervé Bellon  Abdelkrim El Archi  Mohamed Sahabi  Jean-Pierre Rehault  Jean-Louis Olivet  Abdel M. Aghzer 《Comptes Rendus Geoscience》2006,338(5):359-367

The Adrar Souttouf belt (Western Sahara) lies in the northern part of the Mauritanide belt and was considered as a part of the Hercynian Mauritanian-Appalachian belt. Recently the presence of a Panafrican protolith (595 Ma) was evidenced by the age of inherited zircons from an eclogitic unit and led to consider complex Panafrican events included in the Hercynian belt, as in the central and southern Mauritanide belt. Our new field survey completed by ten KAr dating (whole rocks and separate minerals) confirmed that multiphased Panafrican formations outcrop within the center of the Adrar Souttouf massif. Diverse events ranged from ca. 1000 to 500 Ma, some of them being indicative of an oceanic type environment and metamorphism. The 1000 Ma metamorphic event is recorded for the first time in the West African craton. A large Hercynian remobilisation is also evidenced. To cite this article: M. Villeneuve et al., C. R. Geoscience 338 (2006).  相似文献   

Rossby wave interactions with Mediterranean and subtropical latitudes     

Dominique Lambert  Jean-Pierre Cammas 《Meteorology and Atmospheric Physics》2010,108(3-4):83-94

The downstream influence of a Rossby wave on weather conditions in the Mediterranean and North Africa is studied. The objective is to gain a better understanding of the atmospheric processes in these regions and to improve their quantification. The emphasis is placed on high-impact weather events to improve numerical forecasts and warnings about these hazardous weather phenomena. For this purpose, 4 days from 5 to 8 February 1997 are used to investigate both a Mediterranean low and a subtropical African convective situation. Sensitivity studies, using a potential vorticity inversion tool associated with the French atmospheric model ARPEGE, are presented. The Mediterranean surface low under study is shown to be associated with the mid-latitude upper level potential vorticity anomaly, itself associated with a Rossby wave. A subtropical convective cell is shown to be related to upward vertical motions associated with a cut-off low; this cut-off low coming from a mid-latitude Rossby wave.  相似文献