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161.
Boris Shustov Mikhail Sachkov Ana I. Gómez de Castro Maohai Huang Klaus Werner Norbert Kappelmann Isabella Pagano 《Astrophysics and Space Science》2009,320(1-3):187-190
The World Space Observatory UltraViolet (WSO–UV) is an international space mission devoted to UV spectroscopy and imaging. The observatory includes a 170 cm aperture telescope capable of high-resolution and long slit low-resolution spectroscopy, and deep UV and optical imaging. The observatory is designed for observations in the ultraviolet domain where most of astrophysical processes can be efficiently studied with unprecedented capability. 相似文献
162.
The global martian volcanic evolutionary history 总被引:1,自引:0,他引:1
Stephanie C. Werner 《Icarus》2009,201(1):44-68
Viking mission image data revealed the total spatial extent of preserved volcanic surface on Mars. One of the dominating surface expressions is Olympus Mons and the surrounding volcanic province Tharsis. Earlier studies of the global volcanic sequence of events based on stratigraphic relationships and crater count statistics were limited to the image resolution of the Viking orbiter camera. Here, a global investigation based on high-resolution image data gathered by the High-Resolution Stereo Camera (HRSC) during the first years of Mars Express orbiting around Mars is presented. Additionally, Mars Orbiter Camera (MOC) and Thermal Emission Imaging System (THEMIS) images were used for more detailed and complementary information. The results reveal global volcanism during the Noachian period (>3.7 Ga) followed by more focused vent volcanism in three (Tharsis, Elysium, and Circum-Hellas) and later two (Tharsis and Elysium) volcanic provinces. Finally, the volcanic activity became localized to the Tharsis region (about 1.6 Ga ago), where volcanism was active until very recently (200-100 Ma). These age results were expected from radiometric dating of martian meteorites but now verified for extended geological units, mainly found in the Tharsis Montes surroundings, showing prolonged volcanism for more than 3.5 billions years. The volcanic activity on Mars appears episodic, but decaying in intensity and localizing in space. The spatial and temporal extent of martian volcanism based on crater count statistics now provides a much better database for modelling the thermodynamic evolution of Mars. 相似文献
163.
A resampling scheme for regional climate simulations and its performance compared to a dynamical RCM 总被引:5,自引:2,他引:3
B. Orlowsky F.-W. Gerstengarbe P. C. Werner 《Theoretical and Applied Climatology》2008,92(3-4):209-223
Summary A new statistical method for regional climate simulations is introduced. Its simulations are constrained only by the parameters
of a linear regression line for a characteristic climatological variable. Simulated series are generated by resampling from
segments of observation series such that the resulting series comply with the prescribed regression parameters and possess
realistic annual cycles and persistence. The resampling guarantees that the simulated series are physically consistent both
with respect to the combinations of different meteorological variables and to their spatial distribution at each time step.
The resampling approach is evaluated by means of a cross validation experiment for the Elbe river basin: Its simulations are
compared both to an observed climatology and to data simulated by a dynamical RCM. This cross validation shows that the approach
is able to reproduce the observed climatology with respect to statistics such as long-term means, persistence features (e.g.,
dry spells) and extreme events. The agreement of its simulations with the observational data is much closer than for the RCM
data.
Correspondence: B. Orlowsky, Potsdam Institute for Climate Impact Research, P.O. Box 60 12 03, 14412 Potsdam, Germany 相似文献
164.
Recent anomalies of mean temperature of 12 consecutive months – Germany, Europe, Northern Hemisphere
Z. W. Kundzewicz F.-W. Gerstengarbe H. Österle P. C. Werner W. Fricke 《Theoretical and Applied Climatology》2009,95(3-4):417-422
Anomalies of mean air temperature of 12 consecutive months were detected recently at a number of spatial scales: from local via national and continental, to hemispheric. At all these spatial scales, pre-2007 records were exceeded by considerable margins. The recent rise in the mean temperature of 12 consecutive months at several scales has remained largely unnoticed, because the 12-month means are seldom analyzed. Broad attention is typically focused on monthly, seasonal and annual temperatures. Analysis of shifted 12-month periods helps spot peculiar 12-month episodes with remarkable temperature anomalies that do not coincide with a calendar year. Introducing 12-month running mean temperatures into the global warming debate can prove useful. 相似文献
165.
In the hot, dense plasma of solar and stellar interiors, the Coulomb interaction is screened by the surrounding plasma. Although the standard Salpeter approximation for static screening is widely accepted and used in stellar modeling, the question of dynamic screening has been revisited. In particular, Shaviv and Shaviv apply the techniques of molecular dynamics to the conditions in the solar core in order to numerically determine the dynamic screening effect. By directly calculating the motion of ions and electrons due to Coulomb interactions, they compute the effect of screening without the mean-field assumption inherent in the Salpeter approximation. Here we reproduce their numerical analysis of the screening energy in the plasma of the solar core and conclude that the effects of dynamic screening are relevant and should be included in the treatment of the plasma, especially in the computation of stellar nuclear reaction rates. 相似文献
166.
Herbert Lutz Uwe KaulfuSS Torsten Wappler Werner L?hnertz Volker Wilde Dieter F. Mertz Jens Mingram Jens L. Franzen Herbert Frankenh?user Martin Koziol 《《地质学报》英文版》2010,84(4):984-1009
<正>To mark the occasion of the 175th anniversary of the Rheinische Naturforschende Gesellschaft in 2009 and of the centennial of the Mainz Natural History Museum in 2010,we present a short account of our present knowledge of the Eckfeld Maar after 20 years of continuous research.This paper does not attempt to include all of the detailed results on the geology of the Eckfeld site or its biota.To date,nearly 250 papers and books have been published since the start of our project.An up-to-date list of these publications can be found at www.eckfeldermaar. de. 相似文献
167.
Possibilities to sequester anthropogenic CO2 in deep geological formations are being investigated worldwide, but the potential within Switzerland has not yet been evaluated.
This study presents a first-order appraisal based solely on geological criteria collated from the literature. The Swiss Molasse
Basin (SMB) and the adjacent Folded Jura are the only realms of the country where CO2 could conceivably be stored in saline aquifers. Evaluation of geological criteria at the basin-wide scale shows that the
SMB–Jura has moderate potential (score of 0.6 on a scale from 0 to 1) when compared to basins elsewhere. At the intrabasinal
scale, inspection of the stratigraphy reveals four regional candidate aquifers that are sealed by suitable caprocks: top Basement
plus basal Mesozoic sandstones, all sealed by the Anhydrite Group; Upper Muschelkalk sealed by the Gipskeuper; Hauptrogenstein
sealed by the Effinger Member, and Upper Malm plus Lower Cretaceous sealed by the Lower Freshwater Molasse. Nine geological
criteria are defined to evaluate the storage potential of these and other smaller scale candidates. A numerical scoring and
weighting scheme allows the criteria to be assessed simultaneously, permitting the storage potential to be depicted using
the 0–1 scale in contoured maps. Approximately 5,000 km2 of the central SMB exhibits potentials between 0.6 and 0.96. The Fribourg–Olten–Luzern area is the most favoured owing to
the presence of several sealed aquifers within the preferred 800–2,500 m depth interval, and to its low seismicity, low geothermal
gradient, low fault density, and long groundwater residence times. Smaller areas with good potential lie between Zürich and
St. Gallen. In contrast, western Switzerland, the Jura and the southern SMB have markedly poorer potential. Considering only
the portions of the aquifers with potential above 0.6, the theoretical, effective storage capacity of the basin is estimated
to be 2,680 million tonnes of CO2. 相似文献
168.
169.
Zusammenfassung Rb/Sr-Altersbestimmungen an Biotiten aus Gneisen und Graniten des Moldanubikums lieferten übereinstimmende Alterswerte von 330–345 Millionen Jahren. Das Biotitalter eines vormoldanubischen Granat-Disthen-Gneises ergab sich zu 440 Millionen Jahren, das eines Metagranodiorits der Münchberger Gneismasse zu 385 Millionen Jahren. Zirkone aus einem moldamibischen Gneis zeigen nahezu konkordante Alter um 450 Millionen Jahre.Diese Ergebnisse deuten darauf hin, daß die Münchberger Masse sowie weite Teile des Moldanubikums eine frühvaristische Aufheizung, wahrscheinlich im Zuge regionaler Metamorphose, erlebt haben. Die Beziehungen dieser beiden stark metamorphen Komplexe zu den benachbarten weniger beanspruchten Sedimenten des Saxothuringikums (im Falle der Münchberger Masse) und des Barrandiums (im Falle des Moldanubikums) werden im Sinne einer varistischen Stockwerkstektonik erklärt. Die höheren Alterswerte scheinen wenigstens teilweise auf kaledonische Intrusionen hinzuweisen.
Rb/Sr biotite ages of Moldanubian gneisses and granites fall in the range of 330–345 million years (m.y.). The biotite age of a pre-Moldanubian garnetkyanite gneiss was found to be 440 m.y., that of a metagranodiorite of the Münchberg Mass 385 m.y. Zircons from a Moldanubian gneiss yielded nearly concordant ages of approximately 450 m.y.These results indicate that both the Münchberg Mass and large parts of the Moldanubicum have undergone considerable heating during early Variscan (=early Hercynian) time, probably in the course of regional metamorphism. The relations of these strongly metamorphosed complexes with the neighboring less affected sediments of the Saxothuringicum (in the case of the Münchberg Mass) and the Barrandium (in the case of the Moldanubicum) are presumed to be caused by different depths of metamorphism in Variscan time. Higher ages seem to be related at least partly to Caledonian intrusions.
Résumé Des déterminations de la teneur Rb/Sr dans les biotites des gneiss et des granites du Moldanubique ont fourni les indications d'un âge de 330 à 345 millions années. La biotite d'un gneiss à grenat et disthène prémoldanubique a donné l'âge de 440 m.a.; celle d'une métagranodiorite du massif gneissique de Münchberg a fourni l'âge de 450 m.a. Les zircons d'un gneiss moldanubique montrent l'âge approximatif de 450 m.a.Ces résultats indiquent que le gneiss de Münchberg ainsi qu'une grande partie du Moldanubique ont subi une métamorphose varisque ancienne. Les relations entre ces deux ensembles très métamorphiques et les sédiments moins affectés du Saxothuringien et du Barrandien s'expliquent par une tectonique varisque à plusieurs étages structuraux de nature différente. On suppose que les valeurs donnant un âge plus ancien indiquent des intrusions calédoniennes.
/, 330–345 . . -- 440, 385 . . 450 . . , . . .相似文献
170.
Prof. Dr. Paul Karl Hörmann Priv.-Doz. Hans Pichler Prof. Dr. Werner Zeil 《International Journal of Earth Sciences》1973,62(2):397-418
The Puna of NW-Argentina is divided into a Paleozoic basement complex and a late Mesozoic-Cenozoic sedimentary cover. The sedimentary cover was affected by late fracture tectonics and, from middle Tertiary to Quaternary times, invaded by various volcanics.These volcanics can be subdivided into two groups. A stratigraphically older group of volcanic rocks which belongs to the typical calc-alkaline rock series that is also found in the adjacent parts of the Andes.A younger group of volcanics which is similar to the alkaline rock series and possibly of upper mantle origin. The rocks of this group form small isolated occurrences connected to late fracture zones.Comments are made on the relations between these continental basalt-like rocks and the quasi-cratonic structure of the Puna.
Zusammenfassung Die Puna NW-Argentiniens ist strukturell in ein palÄozoisches Grundgebirge und ein jungmesozoisch-kÄnozoisches Deckgebirge gegliedert. Das Deckgebirge ist besonders durch junge Bruchtektonik geprÄgt und wurde vom mittleren TertiÄr bis in das QuartÄr von verschiedenen Vulkaniten durchsetzt.Diese Vulkanite lassen sich in zwei Gruppen einteilen: Eine stratigraphisch Ältere Generation besteht aus typischen Kalkalkali-Serien, wie sie auch in den benachbarten Andenabschnitten vorkommen. Dagegen zeigen die jüngsten Vulkanite eine Verwandtschaft zu Alkali-Serien und dürften aus dem oberen Mantel stammen. Es sind kleine, isolierte Vorkommen, die an junge Bruchstrukturen gebunden sind.Auf den Zusammenhang zwischen diesen kontinentalbasalt-Ähnlichen Gesteinen und der quasi-kratonischen Struktur der Puna wird hingewiesen.
Résumé La Puna de l'Argentine Nord-Ouest est, du point de vue structural, constituée d'un socle paléozoÏque et d'une couverture faite de roches sédimentaires du MésozoÏque supérieur et du CénozoÏque. La couverture est surtout affectée par une tectonique cassante récente et fut recoupée, du Tertiaire moyen jusqu'au Quaternaire, par des roches volcaniques diverses.Ces roches volcaniques peuvent Être divisées en deux groupes: Une génération stratigraphiquement plus ancienne est composée de séries typiquement calcalcalines comme celles qu'on trouve aussi dans les parties voisines des Andes. Par contre les roches volcaniques plus récentes montrent une parenté avec les séries alcalines et auraient leur origine dans le manteau supérieur. Ce sont des venues isolées et de faible extension liées aux fractures récentes.L'accent est mis sur la liaison existant entre ces roches, semblables au basalte continental, et la structure quasi-cratonique de la Puna.
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