Structural, Geochronological and Geochemical Studies on Pre- and Syn-Kinematic Intrusions in the Kangguer - Huangshan Shear Zone, and Implications for Late Paleozoic Tectonic Evolution of the Eastern Chinese North Tianshan, Central Asia     

WANG Bo  CLUZEL Dominique  JAHN Bor-ming  SHU Liangshu  CHEN Yan  BRANQUET Yannick  BARBANSON Luc 《《地质学报》英文版》2013,87(Z1):316-316

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Changes in Mineralogy,Microstructure, Compressive Strength and Intrinsic Permeability of Two Sedimentary Rocks Subjected to High-Temperature Heating     

Xianfeng Liu  Shengyang Yuan  Yannick Sieffert  Stephen Fityus  Olivier Buzzi 《Rock Mechanics and Rock Engineering》2016,49(8):2985-2998

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Wintertime atmospheric response to Atlantic multidecadal variability: effect of stratospheric representation and ocean–atmosphere coupling     

Yannick Peings  Gudrun Magnusdottir 《Climate Dynamics》2016,47(3-4):1029-1047

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Internal structures and dating of non-sulphide Zn deposits using rock magnetism: insights from the Moroccan High Atlas     

Nicolas Charles  Flavien Choulet  Stanislas Sizaret  Yan Chen  Luc Barbanson  Aomar Ennaciri  Lakhlifi Badra  Yannick Branquet 《Mineralium Deposita》2016,51(1):151-175

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Dynamos on stream surfaces of a highly conducting fluid     

Andrew D. Gilbert  Yannick Ponty 《地球物理与天体物理流体动力学》2013,107(1-2):55-95

Abstract

This paper discusses dynamo action in generalisations of the Ponomarenko dynamo at large magnetic Reynolds number. The original Ponomarenko dynamo consists of a spiralling flow in which the stream surfaces are concentric cylinders of circular cross section, and the flow depends only on distance from the axis in cylindrical polar coordinates.

In this study, the stream surfaces are allowed to be cylinders of arbitrary cross section, and the flow is only required to be independent of the coordinate along the cylinder axes. For smooth flows alpha and eddy diffusion effects are identified, in terms of the geometry of the stream surfaces, and asymptotic formulae for growth rates in the limit of large magnetic Reynolds number are obtained. Numerical support for these results is presented using direct simulation of dynamo action in selected flows at high conductivity. Finally the case is considered when in spherical polar coordinates the flow is independent of the azimuthal coordinate and the stream surfaces, which are tori, have arbitrary cross sections.  相似文献   

Exploration of the Outer Solar System by Stellar Occultations     

Françoise Roques  Yannick Boissel  Alain Doressoundiram  Bruno Sicardy  Thomas Widemann 《Earth, Moon, and Planets》2009,105(2-4):201-208

Stellar occultations are a powerful method for exploring the outer solar system, where faintness and small angular diameters prevent us from exploring in details objects like satellites, rings, or Kuiper Belt Objects. Unique kilometric spatial resolutions or better can be reached through that method. Occultations usually observe identified objects whose trajectory is known, though the occultation events might be difficult to predict. It is also possible to explore populations of small objects populations whose density in the sky plane is large enough to search for serendipitous occultations. Various instrumental methods exist for both predicted and serendipitous occultation, both needing fast photometric recordings of target stars.  相似文献   

Photosynthetic response of pico- and nanoplanktonic algae to UVB, UVA and PAR in a high mountain lake   总被引：1，自引：0，他引：1  

Cristiana Callieri  Giuseppe Morabito  Yannick Huot  Patrick J. Neale  Elena Litchman 《Aquatic Sciences - Research Across Boundaries》2001,63(3):286-293

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Incident and in situ irradiance in Lakes Cadagno and Lucerne: A comparison of methods and models     

Patrick J. Neale  Peter Bossard  Yannick Huot  Ruben Sommaruga 《Aquatic Sciences - Research Across Boundaries》2001,63(3):250-264

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Palaeozoic oolitic ironstone of the French Armorican Massif: a chemical and structural trap for orogenic base metal–As–Sb–Au mineralisation during Hercynian strike-slip deformation     

Eric Gloaguen  Yannick Branquet  Philippe Boulvais  Yves Moëlo  Jean-Jacques Chauvel  Pierre-Jacques Chiappero  Eric Marcoux 《Mineralium Deposita》2007,42(4):399-422

In the Saint-Aubin-des-Chateaux quarry (Armorican Hercynian belt, western France), an epigenetic hydrothermal alteration affects an oolitic ironstone layer intercalated within the Lower Ordovician Grès armoricain Formation. The hydrothermal overprint produced pervasive and massive sulphidation with stratoid pyritised lenticular bodies within the oolitic ironstone layer. These sulphide lenses are spatially associated with strike-slip faults and extend laterally from them. After the massive sulphidation stage (Fe–As, stage 1), subsequent fracturing allowed the deposition of base metals (stage 2) and Pb–Sb–Au (stage 3) parageneses in veins. The dominant brittle structures are vertical extension veins, conjugate shear veins and strike-slip faults of various orders. All these structures are filled with the same paragenetic sequence. Deformation analysis allows the identification of structures that developed incrementally via right-lateral simple shear compatible with bulk strain affecting the Central Armorican Domain. Each increment corresponds to a fracture set filled with specific parageneses. Successive hydrothermal pulses reflect clockwise rotation of the horizontal shortening direction. Geothermometry on chlorite and arsenopyrite shows an input of hot hydrothermal fluids (maximum of 390–350°C) during the main sulphide stage 1. The subsequent stages present a marked temperature drop (300–275°C). Lead isotopes suggest that the lead source is similar for all hydrothermal stages and corresponds to the underlying Neo-Proterozoic basement. Lead isotope data, relative ages of deformation and comparison with neighbouring deposits suggest that large-scale fluid pulses occurred during the whole Hercynian orogeny rather than pulses restricted to the late Hercynian period. The vicinity of the Hercynian internal domain appears as a key control for deformation and fluid flow in the oolitic ironstones, which acted as a chemical and structural trap for the hydrothermal fluids. The epigenetic mineralisation of Saint-Aubin-des-Chateaux appears to be very similar to epigenetic sulphidation described in banded iron formation-hosted gold deposits.  相似文献   

Solar and anthropogenic imprints on Lake Masoko (southern Tanzania) during the last 500 years   总被引：1，自引：0，他引：1  

Yannick Garcin  David Williamson  Laurent Bergonzini  Olivier Radakovitch  Annie Vincens  Guillaume Buchet  Joël Guiot  Simon Brewer  Pierre-Etienne Mathé  Amos Majule 《Journal of Paleolimnology》2007,37(4):475-490

The Masoko crater-lake in southern Tanzania provides a continuous record of environmental changes covering the last 500 years. Multi-proxy studies were performed on a 52 cm sediment core retrieved from the deepest part of the lake. Magnetic, organic carbon, geochemical proxies and pollen assemblages indicate a dry climate during the ‘Little Ice Age’ (AD 1550–1850), confirming that the LIA in eastern Africa resulted in marked and synchronous hydrological changes. However, the direction of response varies between different African lakes (low versus high lake-levels), indicating strong regional contrasts that prevent the clear identification of climate trends over eastern Africa at this time. Inferred changes in Masoko lake-levels closely resemble the record of solar activity cycles, indicating a possible control of solar activity on the climate in this area. This observation supports previous results from East African lakes, and extends this relationship southward. Finally, anthropogenic impact is observed in the Masoko sediments during the last 60 years, suggesting that human disturbance significantly affected this remote basin during colonial and post-colonial times.  相似文献