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1.
Arslan Muhammad Kaminski Michael A. Tawabini Bassam S. Ilyas Muhammad Frontalini Fabrizio 《Arabian Journal of Geosciences》2016,9(4):1-22
The Uromia–Dokhtar Magmatic Arc (UDMA) is a northwest–southeast trending magmatic belt which is formed due to oblique subduction of Neotethys underneath Central Iran and dominantly comprises magmatic rocks. The Jebal-e-Barez Plutonic Complex (JBPC) is located southeast of the UDMA and composed of quartz diorite, granodiorite, granite, and alkali granite. Magmatic enclaves, ranging in composition from felsic to mafic, are abundant in the studied rocks. Based on the whole rock and mineral chemistry study, the granitoids are typically medium-high K calc-alkaline and metaluminous to peraluminous that show characteristics of I-type granitoids. The high field strength (HFS) and large ionic radius lithophile (LIL) element geochemistry suggests fractional crystallization as a major process in the evolution of the JBPC. The tectonomagmatic setting of the granitoids is compatible with the arc-related granitic suite, a pre-plate collision granitic suite, and a syncollision granitic suite. Field observations and petrographic and geochemical studies suggest that the rocks in this area are I-type granitoids and continental collision granitoids (CCG), continental arc granitoids (CAG), and island arc granitoid (IAG) subsections. The geothermobarometry based on the electron probe microanalysis of amphibole, feldspars, and biotite from selected rocks of JBPC implies that the complex formed at high-level depths (i.e., 9–12 km; upper continental crust) and at temperatures ranging from 650 to 750 °C under oxidation conditions. It seems that JBPC is located within a shear zone period, and structural setting of JBPC is extensional shear fractures which are product of transpression tectonic regime. All available data suggested that these granitoids may be derived from a magmatic arc that was formed by northeastern ward subduction of the Neotethyan oceanic crust beneath the Central Iran in Paleogene and subsequent collision between the Arabian and Iranian plates in Miocene.
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E. Kaminski A.-L. Chenet C. Jaupart V. Courtillot 《Earth and Planetary Science Letters》2011,301(1-2):171-178
Turbulent volcanic plumes disperse fine ash particles and toxic gases in the atmosphere and can lead to significant temperature drops in the atmosphere. In the geological past, the emplacement of large continental flood basalts (CFB) has been associated with large changes in the global environment and extinctions of biological species. The variable intensity of environmental changes induced by otherwise similar CFB events, however, begs for a reevaluation of physical controls on the environmental impact of volcanic eruptions. The climatic impact of an eruption depends on its ability to inject gases in the stratosphere and on the eruption rate. Using integral models of turbulent plumes above line and point sources, we find that mass rate estimates for CFBs are in general not large enough for volcanic plumes to reach the stratosphere on their own. Basaltic eruptions, however, are also associated with widespread lava flows which lose large amounts of heat and generate convection in the atmosphere. This form of convection, known as penetrative convection, acts to erode the stably stratified lower atmosphere and generates a thick well-mixed heated atmospheric layer in a few hours. The added buoyancy provided by such a layer almost always ensures that volcanic gases get transported to the stratosphere. The environmental consequences of CFBs are therefore controlled not by the inputs to the atmosphere from individual volcanic plumes, but by the dynamic response of the climate system to a succession of short eruptive pulses within a longer-lasting eruption sequence. 相似文献
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Ocean Dynamics - Fatigue damage of offshore floating structures is a long-term cumulative process, which is mainly attributed to ocean waves. The natural variability and human-induced climate... 相似文献
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Hanner MS Tokunaga AT Golisch WF Griep DM Kaminski CD 《Astronomy and Astrophysics》1987,187(1-2):653-660
2 to 20 micrometers photometry of the inner dust coma of comet Halley was obtained at the NASA IRTF on Mar 6.85, 12.8, 13.75, 17.7, and 24.8. Positions offset 10" were measured as well as the central brightness. The strength of the 10 micrometers emission feature was observed to vary with location in the coma. The infrared emission is in general agreement with the dust size distribution measured from the Vega and Giotto spacecraft. Mar 6.8, 17.7, and 24.8 corresponded to strong dust jet activity. The strength of the 10 micrometers silicate emission is shown to be a sensitive indicator of grain size and thus of jet activity. Dust production rate on March 13.75, 6 h before Giotto encounter, was approximately 10(7) gm s-1. 相似文献
6.
Ingo Drummen MingKang Wu Miroslaw Lech Kaminski Torgeir Moan 《Ocean Engineering》2009,36(15-16):1208-1216
Previous studies of response conditioned wave methods have been focused on their applicability to the prediction of extreme nonlinear wave-induced load effects. The results showed that theses methods can be used to accurately and efficiently predict the nonlinear short-term probability distributions for rigid hull responses. This has led us to investigate how response conditioned wave methods can be used for long-term nonlinear fatigue analyses, and with which accuracy this can be done. In this paper we present the results from our investigation. The studies were performed using a container vessel with a length between perpendiculars of 281 m. Calculations were done with a nonlinear strip theory method in which the hull of the vessel was assumed to be rigid. The most likely response wave (MLRW) method was used to condition the waves. Only head seas were considered. We found that the MLRW method under-predicted the long-term fatigue damage by 3%. The method, however, required a simulation time that was approximately three orders of magnitude less than that required for a conventional long-term nonlinear analysis based on random irregular waves. A preliminary investigation showed that due to lacking springing and whipping contributions the MLRW method under-predicted the fatigue damage for a flexible hull by approximately 50%. Several comments about a more accurate extension of the proposed method to flexible hulls are included. 相似文献
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J. Mechie C. Prodehl K. Fuchs W. Kaminski J. Flick A. Hirn J. Ansorge R. King 《Tectonophysics》1982,90(1-2)
This paper presents some data and results from a seismic refraction experiment, completed mainly in 1979 in the Rhenish Massif, Federal Republic of Germany and extending through Luxembourg and Belgium into the Paris Basin in France.Velocity-depth functions have been derived for each record section independently, based on the assumption that velocity varies only with depth: these models are being improved upon by time-term and ray-tracing methods capable of handling laterally varying velocity structures and by calculating synthetic seismograms.The Pg phase which is observed very clearly on all record sections represents a refracted wave, with velocity generally > 6 km/s, from depths below 1.5–5.5 km. Along the 600 km long main profile one intracrustal reflection can usually be recognized, while from the three shorter crossing profiles in the massif two intracrustal reflectors can always be seen. Beneath much of the main profile the crust-mantle boundary is either a first order discontinuity or thin (< 1 km) transition zone at ~30 km depth. However, beneath the Ardennes and West Eifel there is a 6–12 km thick transition zone before a velocity of 8.1 km/s is reached at ~36 km depth. Beneath the crossing profiles, there is generally a transition zone < 3 km thick between crust and mantle. In some cases, there can be recognized at the top of the mantle a thin high velocity layer which is underlain by a low velocity layer which, in turn, is underlain by a reflector 4–11 km below the crust-mantle boundary. 相似文献
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Dr. Egbert Haase Heinz Kaminski Professor Dr. dr. h.c. Max Pfannenstiel 《Ocean Dynamics》1969,22(5):193-204
Zusammenfassung Während man schon seit einiger Zeit Satelliten-Luftbilder für Festlandsbereiche interpretierte, nahm man allgemein an, daß die Meere auf diesen Bildern von einem einheitlichen und undifferenzierten Schwarz wiedergegeben würden. Es stellte sich aber heraus, daß auf manchen Bildern im Bereich der Meere deutlich verschiedene Grautönungen zu erkennen sind, die die Vermutung aufkommen lassen, es könne hier ein primärer oder zumindest sekundärer Zusammenhang mit submarinen Strukturen bestehen und es müßten sich somit Satelliten-Luftbilder auch meeresmorphologisch auswerten lassen.Zur Prüfung dieser Möglichkeit wurden in der vorliegenden Arbeit aus einer Fülle von Aufnahmen 27 Satelliten-Luftbilder mit entsprechenden Seekarten und anderen Unterlagen verglichen. Es zeigten sich an einigen Stellen verblüffende Übereinstimmungen von gewissen Grautönungen mit bekannten submarinen Formen, während an vielen anderen Stellen zunächst nur unsichere Aussagen möglich sind. Vor allem läßt sich derzeit noch nicht entscheiden, ob und wieweit primäre oder sekundäre Zusammenhänge bestehen.Die zur Beurteilung der Satellitenbilder notwendigen technischen Angaben bezüglich des Aufnahme- und Übertragungsverfahrens werden kurz resumiert, ausführlicher wird darüber an anderen Stellen (vgl. Schrifttum) berichtet.Eine kritische Diskussion des Problems der Eindringtiefe von Licht in Wasser führte zu der Annahme, daß im Bereich des Sonnenreflexes größere Tiefen als bislang vermutet ausgeleuchtet werden und sich aus der Zusammenschau aus großer Höhe veränderte optische Bedingungen ergeben können, als wir sie gewohnt sind.Insgesamt sprechen die Ergebnisse dafür, daß die Aussagefähigkeit der Methode noch an technischen Mängeln und dergleichen leidet, im Prinzip aber doch neue Beiträge zur Ozeanographie erwarten läßt.
Essay of an ocean-morphological interpretation of Satellite-air-Pictures
Summary While for some time, Satellite-air-Pictures have already been interpreted for evaluation in the continental sphere, it was generally assumed that the oceans in such pictures were shown in an uniform and undifferentiated black colour. However, it was concluded that on some of these photos, showing the oceans, greyish shades were clearly visible which fact led to the assumption that one is confronted here primarily or, at least, secondarily by a coherence with submarine structures and, therefore, Satellite-air-Photos could perhaps also be construed in an ocean-morphological way.In order to test such a possibility, 27 Satellite-air-Photos out of a lot of pictures have been compared with the respective sea-charts and other data. In some instances, amazing conformities of certain greyish hues with the known substratal forms got visible, while in many other spots, so far, only vague statements can be made. First of all, at this point, it cannot as yet be decided whether and how far a primary or secondary context exists.The necessary technical data for the evaluation of such Satellite-air-Photos, with reference to the receiving and transmitting procedures, will be summarized in short, yet reports in greater detail can be found in the comparable literature.A critical discussion of the problems of depth of light-penetration into the water led us to the assumption that in the sphere of sunreflexes greater depths than so far presumed can be reached and, by the synoptical view from enormous heights, completely changed optical conditions may result, than we are so far used until now.Altogether, the results prove that the capacity of this method is still suffering from technical shortcomings, principally however, new contributions to oceanography can be expected.
Essai d'une exploitation des images par satellites pour la morphologie marine
Résumé Tandis que depuis quelque temps déjà on interprétait des images par satellites de zones continentales, il était admis en général que les mers, sur ces images, seraient rendues par un «noir» uniforme sans nuances. Mais en fait, sur plus d'une image, on peut reconnaître distinctement dans les zones maritimes diverses tonalités de gris qui donnent à penser qu'il pourrait y avoir là une relation de premier ou tout au moins de second ordre avec des structures sous-marines. Dans ces conditions des images par satellites devraient offrir un intérêt pour la morphologie marine.Afin de vérifier cette possibilité, dans la présente étude, on a comparé 27 images par satellites, tirées d'un grand nombre de prises de vues, avec les cartes marines correspondantes et d'autres documents. En quelques points apparuent des concordances surprenantes entre certains tons de gris et des formes sous-marines connues, tandis qu'en beaucoup d'autres endroits on ne peut encore rien préciser pour le moment. Avant tout, en l'état actuel des choses, on ne peut encore affirmer qu'il existe — et dans quelle mesure — des concordances d'ordre primaire ou secondaire.Les données techniques nécessaires pour l'appréciation des images par satellites en ce qui concerne les procédés de prises de vue et de transmission, sont résumées succinctement; elles sont traitées de façon plus détaillée ailleurs (voir bibliographie).Une discussion critique du problème de la profondeur de pénétration de la lumière dans l'eau, permet de supposer que dans la zone où pénètre la lumière solaire, des profondeurs plus grandes que celles admises jusqu'alors sont éclairées et aussi que de la «vue d'ensemble», de haute altitude, peuvent résulter des conditions optiques qui diffèrent de celles auxquelles nous sommes accoutumés.Dans l'ensemble les résultats montrent que les informations à attendre de la méthode, souffrent encore d'un insuffisance de moyens techniques et autres mais laisse entrevoir, en principe, de nouvelles contributions à l'océanographie.相似文献
9.
Jacek W Kaminski David A Plummer Lori Neary John C McConnell Joanna Struzewska Lech Lobocki 《Physics and Chemistry of the Earth》2002,27(35):1517-1524
A three-dimensional air quality model (MC2-AQ) developed for studying oxidant chemistry on regional to urban scales over North America was adapted and implemented for European conditions. The modelling system is based on the Canadian Mesoscale Compressible Community (MC2) Model, a non-hydrostatic meteorological model, to which modules permitting on-line calculations of chemical transformations, anthropogenic and biogenic emissions, and deposition were added. The transport of chemical species is done on the same grid and with the same advection, convection, and diffusion schemes as are used for the meteorological fields. The developed model is highly flexible and was adapted to different scales by allowing for self-nesting. In this paper we present model results for a high-ozone episode, June 18–26, 2000, over Europe. The modelling system was able to reproduce general characteristics (growth, extent, and dissipation) of the pollution episode. Accumulation of ozone precursors during weak wind and high-temperature synoptic conditions was essential for episode formation. Subsequent episode development and advancement across Europe was driven by frontal systems. A stationary front associated with a low-pressure system over Ukraine prevented the further eastward transport of the polluted air mass. The episode was terminated after the passage of a cold front advecting relatively clean Atlantic air mass. 相似文献
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