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1.
Peter Luger M. Gröschke M. Bussmann A. Dina W. Mette A. Uhmann H. Kallenbach 《International Journal of Earth Sciences》1994,83(4):711-727
The Jurassic and Cretaceous sedimentary history of northern Somalia and the Morondava Basin of south-western Madagascar have been studied. Both regions display an independent facial development; however, a comparison of the sequential evolution of the Mesozoic sedimentary successions in these two presently widely separated areas reveals a surprisingly high level of similarity, which probably reflects major events during the disintegration of Eastern Gondwana during the Jurassic and Cretaceous. Although in Jurassic times the onset of transgressions and regressions in both areas compares well with eustatic development, major deviations in combination with the tectonic activities of different degrees are observed in the Early and Late Cretaceous synchronously in both regions. Transgressions are observed in Toarcian, Bajocian (not dated in northern Somalia), Callovian, Valanginian (Madagascar only), Aptian and Campanian times. Tectonism is noted before the Aptian and Campanian transgressions in northern Somalia and the Morondava Basin of south-western Madagascar. 相似文献
2.
Dr. Heinrich Kallenbach 《International Journal of Earth Sciences》1972,61(1):302-322
Zusammenfassung Am Westrand des Murzukbeckens ist über marinem Karbon eine etwa 800 m mächtige kontinentale, vorwiegend fluviatile Sedimentfolge von roten und braunen Sandsteinen und zwischengelagerten Tonsteinen aufgeschlossen. An der Messak-Schichtstufe wurden an drei Stellen korrelierbare Profile aufgenommen. Die Schichtfolge ließ sich nach feldgeologischen Befunden von unten nach oben in Tilemsin-Schichten und Messak-Sandstein gliedern.Die sedimentologischen Untersuchungen, die sich vorwiegend auf die Tonstein-Horizonte erstreckten, ergaben in der äußerlich gleichartigen Sedimentfolge kontrastreiche Unterschiede der Mineralvergesellschaftung. Die Tilemsin-Schichten sind durch Illit/ Montmorillonit-Vormacht und selektive Feldspatverwitterung gekennzeichnet. Sie müssen auf ein Abtragungsgebiet bezogen werden, in dem relativ milde Verwitterungsbedingungen eines semiariden bis semihumid-tropischen Klimas herrschten. Demgegenüber zeigt der Messak-Sandstein starke Kaolinit-Vormacht und völlige Feldspatzersetzung. Diese Sedimente bestehen aus den umgelagerten Produkten intensiver, lateritischer Verwitterung eines humid-tropischen Klimabereiches. Das Profil zeigt fließende Übergänge und zeugt von einem allmählichen Klimawechsel. Im Gegensatz zu den Tilemsin-Schichten gehört der Messak-Sandstein als Endglied der Entwicklung zur Nubischen Fazies, die im Sinne der siderolithic facies vonMillot (1970) durch die Produkte einer humid-tropischen Verwitterung bestimmt wird.
At the Western flank of the Murzuk basin, a sequence of about 800 m of continental, mainly fluviatile red and brown sandstone with intercalated clay is exposed, overlying marine strata of Carboniferous age. Three sections at the Messak escarpment were investigated. On the basis of field evidence, the sequence was subdivided into Tilemsin Formation (bottom) and Messak Sandstone (top).This study dealing primarily with the clay units, revealed significant differences in mineral association despite of the homogeneous appearance. The Tilemsin Formation is characterized by predominance of illite, montmorillonite, and selective feldspar breakdown. These sediments are derived from an area of relatively mild weathering conditions in a semi-arid to semihumid-tropical climate. In contrast, in the Messak Sandstone kaolinite is predominant, and feldspars and mica are lacking. These sediments are reworked products of intense lateritic weathering of a humid-tropical climate. The transitions within the section are gradual, thus indicate gradual climatic changes. In contrast to the Tilemsin Formation, the Messak Sandstone represents the final stage of the climatic development; it belongs to the Nubian facies which as siderolithic facies sensuMillot (1970) is characterized by the products of humid-tropical weathering.
Résumé Sur la marge ouest du bassin de Mourzouk est exposée, au-dessus du Carbonifère marin, une succession continentale d'environ 800 m de grès rouges et bruns, intercalés d'argiles et à prépondérance fluviatile. Trois sections corrélatives ont été prélevées à l'escarpement de Messak. D'après les observations du terrain géologique, il a été possible de diviser la succession, de bas en haut, en Couches de Tilemsin et en Grès de Messak.Les études sédimentologiques effectuées pour la plupart sur des horizons d'argile ont démontré des différences essentielles dans l'association minéralogique malgré son apparence homogène. Les Couches de Tilemsin sont caractérisées par une prédominance d'illite/montmorillonite et une décomposition sélective de feldspath; elles se rapportent certainement à une région d'érosion où régnaient les conditions douces de décomposition d'un climat semi-aride à tropical semi-humide. En revanche, les grès de Messak présentent une dominance de kaolinite et une décomposition totale de feldspath; ces sédiments se composent des produits remaniés de la décomposition latéritique intensive d'un domaine tropical humide. La section offre des transitions coulantes attestant des variations climatiques graduelles. Les Grès de Messak, en tant que membre terminal du développement, appartiennent — contrairement aux Couches de Tilemsin — au « faciès du Nubie », faciès caractérisé au sens du « siderolithic facies » deMillot (1970), par les produits d'une décomposition humide-tropicale.
Murzuk , . Messak . Tilemsin Messak.- , , . Tilemsin / . . , Messak . - . , . — Messak — siderolithic facies (1970) , - .相似文献
3.
R. Kallenbach J. Geiss G. Gloeckler R. von Steiger 《Astrophysics and Space Science》2000,274(1-2):97-114
Measurements of the composition and spatial distribution of pick-up ions inside the heliosphere are reviewed. The first interstellar
4He+pick-up ions were detected with the SULEICA instrument on the AMPTE spacecraft near Earth's orbit. Most data on pick-up ions
were taken in the solar-wind and suprathermal energy range of SWICS on Ulysses while the spacecraft cruised from 1.4 to 5.4
AU and explored the high-latitude heliosphere and solar wind from the ecliptic to ± 80° heliolatitude. This includes the discovery of H+, 4He++, 3He+, N+,O+, and Ne+ pick-up ions that originate from the interstellar neutralgas penetrating the heliosphere. From their fluxes properties of
the interaction region between the heliosphere and the Local Interstellar Cloud such as the limits on filtration and the strength
of the interstellar magnetic field have been revealed. Detailed analysis of the velocity distributions of pick-up ions led
to 1) the discovery of a new distinct source, the so-called Inner Source, consisting of atoms released from interstellar and
interplanetary dust inside the heliosphere, 2) the determination of pick-up ion transport parameters such as the long mean
free path for pitch-angle scattering of order1 AU, and 3) detailed knowledge on the very preferential injection and acceleration
of pick-up ions during interplanetary energetic particle events such as Co-rotating Interaction Regions and Coronal Mass Ejections.
SWICS measurements have fully confirmed the theory of Fisk, Koslovsky, and Ramaty that pick-up ions derived from the interstellar
gas are the dominant source of the Anomalous Cosmic Rays; they are pre-accelerated inside the heliosphere and re-accelerated
at the solar-wind Termination Shock according to Pesses, Eichler, and Jokipii. The data indicate that the Inner Source of
pick-up ionsis largely responsible for the occurence of C+ in the Anomalous Cosmic Rays. The abundances of recently discovered Inner-Source Mg+ and Si+ are solar-wind like and consistent with their abundances in the energetic particles associated with Co-rotating Interaction
Regions. Knowledge on the injection and acceleration processes in Co-rotating Interaction Regions is applied to discuss the
current observational evidence for the Interplanetary Focusing Cone of the interstellar neutral gas due to the Sun's gravitational
force. The 25–150 keV/amu suprathermal 4He+ pick-up ion fluxes measured by CELIAS/STOF on board SOHO over 360° of ecliptic longitude represent a `local' ionization and acceleration of interstellar atoms at 1 AU or smaller heliocentric
distances. Completing the first limited data set of SULEICA/AMPTE on 4He+ pick-up ions they indicate a density enhancement in the Interplanetary Focusing Cone which is confirmed by recent SWICS/ACE
data. Clear evidence for signatures in ecliptic longitude are found in the data on energetic neutral H fluxes observed with
the CELIAS/HSTOF sensor on board SOHO. These fluxes are enhanced in the upstream and downstream directions of the interstellar
wind. Detection of energetic H atoms, which propagate unaffected by the Heliospheric Magnetic Field, provided for the first
time a diagnostic tool for observations near Earth to analyze the structure in ecliptic longitude of the interface region
between the heliosphere and the Local Interstellar Cloud.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
4.
Christian Koch Ulrich Christensen Reinald Kallenbach 《Planetary and Space Science》2008,56(9):1226-1237
Solar tidal forces generate elevation changes of Mercury's surface of the order 1 m within one Hermean year, and solar torques on the non-symmetric permanent mass distribution of the planet cause an uneven rotation of Mercury's surface with a libration amplitude of the order of 40 arcsec. Knowledge of the precise reaction of the planet to tidal forcing, expressed by the Love numbers h2 and k2, as well as accurate knowledge of the amplitude of forced libration Φlib, puts constraints on the internal structure, for example the state and the size of the core. The MESSENGER and BepiColombo missions to Mercury carry laser altimeters, whose primary goal is to accurately map the topography. Here we investigate if the Love number h2 and the amplitude of forced libration can be determined together with the static topography of the planet from a global altimetry record. We do this by creating synthetic altimeter data for the nominal orbit of BepiColombo over the nominal mission duration of approximately four Mercury years and inverting them for the static and time-dependent parts of the topography. We assume purely Gaussian noise. We find that it is possible to extract both parameters h2 and Φlib with an accuracy of approximately 10%, while the static topography coefficients of a spherical harmonic expansion can be determined simultaneously with an accuracy at the centimetre level. Extraction of the static topography to higher harmonic degrees improves the precision of the measurement of h2 and Φlib. The simulation results demonstrate that it seems feasible to test current models on Mercury's interior with sufficient precision using BepiColombo Laser Altimeter data. 相似文献
5.
Abstract In a further step to assess processes leading to the complicated secular trend of the isotopic composition of N implanted in lunar regolith, we investigate mechanisms fractionating solar energetic particles (SEPs). We conclude that such mechanisms are likely to occur, most probably producing an enrichment of 15N over 14N in SEPs over the photospheric abundance ratio. Simultaneously, 22Ne is enriched over 20Ne but to a lesser extent. An enrichment of the heavy Ne isotope is observed in the suprathermal solar particles, implanted in the lunar regolith. Hence, the now well-established difference between the isotopic composition of suprathermal Ne and solar wind Ne in the lunar regolith might be taken as evidence for the validity of this model. The present-day fluxes of energetic particles produced in impulsive flare events, capable to produce such isotopic fractionations are, however, orders of magnitude below the required amounts to explain the lunar observations. The details of the secular variation of the N isotopic composition remain an enigma. 相似文献
6.
Dr. Heinrich Kallenbach 《International Journal of Earth Sciences》1966,55(3):582-607
Zusammenfassung An ausgewählten, stratigraphisch gut gegliederten Profilen wurden Mineralbestand und Bildungsumstände der würmeiszeitlichen Lösse sowie ihrer unterlagernden Schichten mit geologischen, sedimentpetrographischen und mineralogischen Methoden untersucht. Schwermineralgehalt und paläogeographische Folgerungen machen die Alpen als primäres Liefergebiet wahrscheinlich. Die vorwiegend detritischen Tonminerale wurden postsedimentär durch Klima und Bodenbildung regional unterschiedlich beeinflußt. Während in den alpennahen, niederschlagsreichen Gebieten mit hoher Bodenauswaschung der Tonmineralbestand (vorherrschend Illit, neben Kaolinit und Chlorit) keine merkliche Veränderung zeigt, werden in den alpenfernen, relativ trockenen Gebieten Umwandlungen von Illit in Montmorillonit beobachtet. Ein Absinken des pH-Wertes (pH 4 bis 5) unter dem Einfluß von Staunässe und Bodenbildung führte zu einer verstärkten Verwitterung der Silikate und begünstigte eine Neubildung von Kaolinit.
Aus dem Geologischen Institut der Technischen Hochschule München und dem Mineralogischen Institut der Universität Erlangen-Nürnberg. 相似文献
In the last glacial period (Würm) the origin of loess in Southern Bavaria is to be found in the Alps, as the mineral components of the loess indicate. After the glacial deposit the mainly detrital clay minerals were influenced in different ways by climate and soil formation. In regions rich in rainfall the clay mineral component (Illit, Kaolinit, Chlorit) remained almost the same, while in regions poor in rainfall a transformation from Illit to Montmorillonit was to be observed. Constant moisture of the soil produced in acid reaction (pH 4–5) a more intensive weathering of the silicates and supported a new formation of Kaolinit.
Résumé En Bavarie du Sud, se trouver la région d'origin du loess de la dernière période glaciale (Würm) dans les Alpes, a qui est indique par les composants minéraux dans le loess. Aprés le dépôt l'argile assentiellement détritique fut inffuencée de manière différente par le climat et la pédogénèse. Dans les régions riche en pluie le composant d'argile (Illit, Kaolinit, Chlorit) restait presque inchangé, tandis que dans les régions qui out peude pluie on observait une transformation de Illit en Montmorillonit. L'humidité constante du sol accidité pH 4–5 causait une plus forte altération des silicates et favorisait la nouvelle formation de Kaolinit.
— , , . — pH 5 — .
Aus dem Geologischen Institut der Technischen Hochschule München und dem Mineralogischen Institut der Universität Erlangen-Nürnberg. 相似文献
7.
Dr. Frits Hendriks Prof. Dr. Heinrich Kallenbach 《International Journal of Earth Sciences》1986,75(2):445-460
The Abu Ballas Formation in the Western Desert of Egypt represents a marine intercalation within fluvial, Nubia-type sandstones. These deposits document an extensive transgression of Aptian age flooding the Dakhla Basin from north to south. Due to this first advance of the Tethyan sea during the Cretaceous, sediments of open and marginal marine provenance were accumulated in the SE of the basin.The sedimentary succession of the open marine facies is divided into five lithostratigraphic units which reflect that deposition was largely controlled by one single transgressive-regressive event. The transgressive sequence in the lower part of the formation comprises sandstones of a backshore to foreshore environment (unit 1) which are overlain by offshore claystones (unit 2). The middle portion of the sedimentary succession consists of silty and sandy strata (unit 3) which are attributed to large-scale redepositional processes due to intensified bottom currents during the maximum extension of the sea. These sediments are capped by offshore originated claystones (unit 4) grading upwards into siltstones and sandstones of transition-zone to backshore environments (unit 5), which indicate a gradual regression.This stratigraphic sequence documenting a retrograding-prograding shoreline due to the transgression and regression of the Aptian sea, interfingers with silty and sandy deposits of the marginal marine facies of the Abu Ballas Formation. Comparable to the lithostratigraphic units 1 and 5 these strata represent a variety of sedimentary environments ranging from the backshore to the transition zone. They were accumulated on the western slope of the Kharga Uplift bounding the Dakhla Basin towards the east, which was partially flooded while the sea had its maximum extension.
Zusammenfassung Die Abu Balks-Formation in der Western Desert Ägyptens stellt eine marine Einschaltung innerhalb von fluviatilen Sandsteinen Nubischen Typs dar. Diese Schichtenfolge dokumentiert eine weitflächige, nach Süden hin in das Dakhla-Becken vorgreifende Transgression aptischen Alters. Im Verlauf dieses ersten Vorstoßes der Tethys während der Kreide wurden im SE des Beckens Sedimente offen und randlich mariner Provenienz abgelagert.Die Ablagerungen der offen marinen Fazies werden in fünf lithostratigraphische Einheiten unterteilt, deren vertikale Abfolge eine Sedimentakkumulation im Rahmen einer Transgression und einer nachfolgenden Regression widerspiegelt. Die transgressive Schichtenfolge im unteren Teil der Formation umfaßt Sandsteine mit Merkmalen einer Strandsedimentation (Einheit 1), die von Peliten eines untiefen Schelfs (Einheit 2) überlagert werden. Höher folgen siltige und sandige Schichten (Einheit 3), die auf großräumige Umlagerungsvorgänge im Becken durch bodennahe Strömungen während der maximalen Ausdehnung des Meeres zurückgeführt werden. Die regressive Entwicklung setzt ein mit einer erneuten Ablagerung von pelitischen Sedimenten eines flachen Schelfmeeres (Einheit 4). Diese gehen zum Hangenden hin über in Siltsteine und Sandsteine (Einheit 5), die zwischen dem Schelf und dem Strandbereich vermitteln und das Ende der Verflachungsphase andeuten.Diese Schichtenfolge, die auf ein anfängliches Zurückweichen und späteres Vorrücken der Küstenlinie im Rahmen von Transgression und anschließender Regression hinweist, verzahnt sich mit siltigen und sandigen Ablagerungen der randlich marinen Fazies der Abu Ballas-Formation. Ähnlich wie die lithostratigraphischen Einheiten 1 und 5 entstammen sie einem Strandbis küstennahen Schelf-Milieu und wurden während der maximalen Ausbreitung des Meeres an der westlichen Flanke des Kharga-Uplifts akkumuliert. Diese Schwellenregion, die das Dakhla-Becken nach Osten begrenzt, war im Apt vermutlich nur teilweise überflutet.
Résumé La formation Abu Ballas du désert occidental d'Egypte représente une intercalation marine dans les grès fluviatiles de type nubien. Cette séquence illustre une large transgression d'âge aptien pénétrant vers le Sud dans le bassin de Dakhla. Au cours de cette première progression de la Téthys pendant le Crétacé, des sédiments d'origine marine et marginolittorale se sont déposés dans la partie SE du bassin.Les couches de facies marin sont diversées en cinq unités lithostratigraphiques, dont la succession verticale refléte une accumulation de sédiments au cours d'une transgression et d'une régression successives. La série transgressive, dans la partie inférieur de la formation, comprend des grès typiques d'une sédimentaion de haute et de basse plage (unité 1), surmontés par des pélites de plate-forme continentale peu profonde (unité 2). Plus haut viennent des chouches silteuses et sableuses (unité 3) qui sont attribuées à des processus de remaniements dans le bassin par les courants de fond pendant l'extension maximale de la mer. La phase régressive commence par un nouveau dépôt de sédiments pelitiques de mer peu profonde (unité 4). Ceux-ci sont suivis vers le haut par des siltites et des grès (unité 5) déposés dans une zône de transition arrière plage/plateforme continentale et indiquant la fin de la régression.Cette série qui indique un recul puis une avancée de la ligne de rivage, par transgression et régression, est interstratifiée de dépôts silteux et sableux de facies marin marginal de la formation Abu Ballas. Semblables aux unités lithostratigraphiques 1 et 5, ces couches témoignent d'un milieu variant de la basse plage à la partie haute du shelf. Elles se sont accumulés au bord ouest du seuil de Kharga au cours de l'extension maximale de la mer aptienne. A cette époque, cette region élevée limitant le bassin de Dakhla vers l'est, n'était probablement inondée qu'en partie.
- . , Dakhla. , - . , — — . , , (1- ), (2- ). , (3- ), . , (4- ). (5- ), . , , -. 1 5, , Kharga. , Dakhla , , , .相似文献
8.
CELIAS - Charge, Element and Isotope Analysis System for SOHO 总被引：1，自引：0，他引：1
D. Hovestadt M. Hilchenbach A. Bürgi B. Klecker P. Laeverenz M. Scholer H. Grünwaldt W. I. Axford S. Livi E. Marsch B. Wilken H. P. Winterhoff F. M. Ipavich P. Bedini M. A. Coplan A. B. Galvin G. Gloeckler P. Bochsler H. Balsiger J. Fischer J. Geiss R. Kallenbach P. Wurz K. -U. Reiche F. Gliem D. L. Judge H. S. Ogawa K. C. Hsieh E. Möbius M. A. Lee G. G. Managadze M. I. Verigin M. Neugebauer 《Solar physics》1995,162(1-2):441-481
The CELIAS experiment on SOHO is designed to measure the mass, ionic charge and energy of the low and high speed solar wind, of suprathermal ions, and of low energy flare particles. Through analysis of the elemental and isotopic abundances, the ionic charge state, and the velocity distributions of ions originating in the solar atmosphere, the investigation focuses on the plasma processes on various temporal and spatial scales in the solar chromosphere, transition zone, and corona. CELIAS includes 3 mass- and charge-discriminating sensors based on the time-of-flight technique: CTOF for the elemental, charge and velocity distribution of the solar wind, MTOF for the elemental and isotopic composition of the solar wind, and STOF for the mass, charge and energy distribution of suprathermal ions. The instrument will provide detailed in situ diagnostics of the solar wind and of accelerated particles, which will complement the optical and spectroscopic investigations of the solar atmosphere on SOHO. CELIAS also contains a Solar Extreme Ultraviolet Monitor, SEM, which continously measures the EUV flux in a wide band of 17 – 70 nm, and a narrow band around the 30.4 nm He II line.Principal-InvestigatorPrincipal-Investigator for data phase 相似文献
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