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111.
Zusammenfassung Der Malm der Ith-Hils-Mulde wird am. SE-Ende des Ith diskordant von Unterkreide überlagert, und im Innern der Mulde sind in einer Umgebung von Jura und Wealden Schichten des Neokom und des Tertiär erhalten, die durch Ablaugung auf dem Salzstock von Weenzen versenkt worden sind. Aus diesen Lagerungsverhältnissen ergibt sich folgende Vorstellung von der Entstehung des Malm-Schichtkammes der Ith-Hils-Mulde:Die Malm- und Wealdenschichten des Ith-Hils-Gebietes sind während ihrer Ablagerung eingemuldet worden; die Mulde ist nach Einebnung ihrer Ränder von den Schichten der marinen Kreide überlagert worden und hat bis zum Ende der Oligozänzeit unter Kreide- und Tertiärschichten gelegen. Soweit diese Schichten infolge einer nacholigozänen Hebung wieder abgetragen worden sind, wurden die Kalke des Unteren und Mittleren Malm in jungtertiärer Zeit als Schichtkamm herausgearbeitet.Der Malm-Schichtkamm der Ith-Hils-Mulde ist insofern ein Schlüssel zur Morphologie des nordwestdeutschen Berglandes, als seine morphologische Entwicklung in allen wesentlichen Phasen aus dem geologischen Befund abgeleitet werden und damit auch für andere Teile dieses Berglandes, deren geologische Überlieferung weniger vollständig ist, als Beispiel gelten kann.
At the south-east spur of the secondary chain of mountains of the Ith situated between the valleys of the Rivers Weser and Leine the Malm of the Ith-Hils Trough is unconformably overlain by the Lower Cretaceous. In the interior of this trough, strata of the Neocomian and of the Tertiary have been preserved in a surrounding of Jurassic and Wealden. Salt dissolution and evacuation have caused these strata to subside on top of the salt dome of Weenzen. From these circumstances of stratification the following concept ensues regarding the formation of the Malm stratum ridge of the Ith-Hils Trough:During strata deposition the Malm and Wealden strata of the Ith-Hils region have been subjected to trough formation. After levelling of its rims the trough has been overlain by strata of the Cretaceous, and, until the end of the Oligocene, it had been situated underneath Cretaceous and Tertiary strata. Insofar as these latter strata have been destroyed again in consequence of a post-oligocene uplift, the limestones of the Lower and Middle Malm have been shaped out as the stratum ridge in the late Tertiary epoch.The Malm stratum ridge of the Ith-Hils Trough represents a key to the explanation of the morphological conditions of the mountainous country of north-western Germany, as the morphological development of the same can be derived from the geological findings in all its essential phases. Thereby the Malm stratum ridge of the Ith-Hils Trough can be set as a validated example for other parts of this stretch of mountainous country, whose structural aspect is less complete.

Résumé Au contrefort sud-est de la chaîne de montagnes de l'Ith située entre les vallées des rivières Weser et Leine, le Malm (Jurassique Supérieur) du synclinal de l'Ith-Hils est couvert par le Crétacé Inférieur sous forme d'une discordance de stratification. A l'intérieur de ce synclinal des strates du Néocomien et du Tertiaire se sont conservées dans un entourage du Jurassique et du Wealdien. Au-dessus du dôme de sel de Weenzen la dissolution et l'écoulement des sels ont causé que ces strates se soient enfoncées. De ces circonstances de stratification le concept suivant s'ensuit en ce qui concerne la formation de la crête de strate du Malm du synclinal de I'Ith-Hils:Pendant le processus de stratification les strates du Malm et du Wealdien de la région de l'Ith-Hils ont subi une formation de synclinal. A la fin du processus de nivellement de ses bords le synclinal a été couvert par les strates du Crétacé (marin), et, jusqu'à la fin de l'Oligocène, il a été situé au-dessous des strates du Crétacé et du Tertiaire. En tant que ces dernières strates ont été enlevées à nouveau en conséquence d'un soulèvement post-oligocène, les calcaires des strates de Malm inférieur et moyen ont été façonnés en qualité de crête de strate à l'époque du Néogène.La crête de strate du Malm du synclinal de l'Ith-Hils représente une explication fondamentale des conditions morphologiques du pays de montagnes de l'Allemagne du nord-ouest jusqu'à un tel point que le développement morphologique de ce pays peut être dérivé des constatations géologiques de l'état récent dans toutes ses phases essentielles. De cette manière la crête de strate du Malm peut servir d'exemple corroboré à d'autres parties de cette région de pays de montagnes, dont l'aspect structurel est moins complet.

Ith-Hilo Ith . , . : , . . . , , .


Vortrag, gehalten auf der 58. Jahrestagung der Geologischen Vereinigung in Göttingen am 19. 2. 1968.  相似文献   
112.
Zusammenfassung Alle einwandfreien Gesteinsanalysen der jungen Vulkanite des süd-ägäischen Raumes (insgesamt 181) wurden nach der von A.Rittmann neu entwickelten Berechnungsmethode (Rittmann-AMS) auf ihren quantitativen Mineralbestand berechnet und ausgewertet. Dabei zeigte sich, daß ein Großteil dieser Vulkanite falsch benannt ist. Der Anteil der Andesite ist wesentlich geringer als bisher angenommen. Ebenso sind keine Basalte vertreten. Der Schwerpunkt der Gesteine fällt in das Latitandesitfeld, wobei besonders stark quarzführende Typen dominieren. Ein Teil der alkalirhyolithischen bis latitandesitischen Vulkanite weist einen teilweise beträchtlichen AI-Überschuß auf, der sich im Auftreten von (errechnetem) Cordierit ausdrückt. Die Entstehung der Magmen des untersuchten Gebietes wird durch Anatexis von sialischem Material verschiedener Zusammensetzung erklärt. Dies wird durch AI-Überschuß, den ausgeprägt pazifischen Charakter, das Auftreten von exogenem Quarz und weitere Indizien gestützt. Die lokal vertretenen Vulkanite mit schwacher atlantischer und mediterraner Tendenz werden durch mäßige und lokale pneumatolytische Differentiation (Alkalizufuhr) der sialisch-anatektischen Magmen gedeutet.
With a new calculation-method for volcanic rocks, recently developed by A.Rittmann (Rittmann-AMS), all available chemical analyses of the young volcanics of the south-aegean Sea (altogether 181) have been calculated. The evaluation proved a wrong denomination for the bulk of these volcanic rocks. More than 50% of the so-called andesites are latitandesites and dacites (nomenclatureStreckeisen, 1965). Likewise no basalts are existing in this area. The latitandesites are mostly quartz-bearing types (on an average between 10 and 15% of free quartz). Many of the alkalirhyolitic to dacitic rocks and some of the latitandesites show a considerable excess of A12O3, which appears in the calculation as cordierite (up to7%). The acid volcanics are explained to have been originated by fusion of sialic material of granitic to granodioritic composition of the upper parts of the crust. The latitandesites and andesites are supposed to be derived by melting of degranitizised sialic material of lower parts of the crust. Characteristics for the sialic origin are: excess of A12O3, the presence of exogenous quartz-relics, the strong calcalcaline serial index and others. In the south-aegean area locally appear volcanics with a weak atlantic or mediterranean serial character. This fact is interpreted by moderate pneumatolytic differentiation (gaseous transfer) of the sialic-anatectic magmas.

Résumé Toutes les analyses chimiques des jeunes roches volcaniques dans la région de la mer Egée sud (en somme 181) ont été calculées et évaluées à l'aide de la nouvelle méthode de A.Rittmann (Rittmann-AMS). Alors on a constaté qu'un grand nombre des roches volcaniques avait été qualifié incorrectement. Plus de 50 pour cent des « andesites » sont latitandesites et dacites. Il n'y a pas de basaltes. La plupart des latitandesites contiennent du quartz. Beaucoup de roches alcalirhyolitiques à latitandesitiques montrent un excès considérable de Al, ce qui apparaît dans la calculation comme cordierite. On explique la formation des magmas par la fusion de différents matériels sialiques. Quelques indices soutiennent cette théorie: l'excès de Al, le caractère typiquement pacifique, la présence de quartz exogène. La présence de roches volcaniques à caractère faiblement atlantique et méditerranéen est expliquée par la différenciation pneumatolytique modérée des magmas sialiques anatectiques.

- , . , , . . .


Herrn Professor Dr. Dr. A.Rittmann zum 75. Geburtstag gewidmet  相似文献   
113.
The development of gypsum maze caves under artesian conditions has been simulated. The numerical model simulations show that the evolution of maze caves in this type of setting requires structural preferences such as laterally extended fissure networks in a horizon of the gypsum layer. Without any structural preferences vertical shafts rather than maze caves are predicted to develop. The most important stage for the development of horizontal caves under artesian conditions is found to be the initial karstification period. During this period the structure of the mature conduit system is established. The solutional enlargement of conduits is spatially extended, total dissolution rates are higher than the later ones.  相似文献   
114.
Vibrios are widespread in the marine environment and a few pathogenic species are known to be commonly associated with outbreaks of diarrheal diseases in humans due to the consumption of raw or improperly cooked seafood. However, there are also many Vibrio species which are potentially pathogenic to vertebrate and invertebrate aquatic animals, and of which little is known. In an attempt to develop rapid PCR detection methods for these latter class of vibrios, we have examined the 16S-23S intergenic spacers (IGSs) of 10 lesser-known Vibrio species and successfully developed species-specific primers for eight of them--Vibrio costicola, V. diazotrophicus, V. fluvialis, V. nigripulchritudo, V. proteolyticus, V. salmonicida, V. splendidus and V. tubiashii. The IGS amplicons were amplified using primers complementary to conserved regions of the 16S and 23S rRNA genes, and cloned into plasmid vectors and sequenced. Analysis of the IGS sequences showed that 37 ribosomal RNA (rrn) operons representing seven different IGS types have been cloned from the 10 vibrios. The three IGS types--IGS(0), IGS(IA) and IGS(Glu)--were the most prevalent forms detected. Multiple alignment of representative sequences of these three IGS types from different Vibrio species revealed several domains of high sequence variability, which were used to design species-specific primers for PCR. The specificity of the primers were evaluated using total DNA prepared from different Vibrio species and bacterial genera. The results showed that the PCR method can be used to reliably detect eight of the 10 Vibrio species in marine waters in this study.  相似文献   
115.
郎庆勇 Jaffe  R 《岩矿测试》1997,16(2):118-127
自1994年6月至1995年3月对(美)迈阿密市大气颗粒物及干、湿沉降物中的多种有机化合物进行了定量分析与监测,并依据分析结果结合分子参数对有机污染水平的季节性变化、气候条件影响和清除机理等进行了探讨。  相似文献   
116.
Most of the mesotrophic to eutrophic lakes in central Europe have been showing signs of oligotrophication during recent years. The question as to how the fish populations would react to this new situation was investigated looking at the growth rate of roachRutilus rutilus (L.) of Lake Sarnen, central Switzerland. The water temperature sum as day-degrees over 12 to 13°C for the months of June to October was found to be the predominant factor governing the marked year-to-year fluctuations of the growth rate. Contrary to expectation, the decreasing trophic state of the lake has not yet manifested itself noticeably in the growth rate.  相似文献   
117.
Summary This paper presents an improved investigation technique for in-situ determination of the deformation properties of rock masses, which are important parameters in the desing of foundations. This technique permits testing on a circular, one square metre area of the rock. In order to obtain reproducible loading conditions when testing, an equipment was introduced that gave almost uniformly distributed loading of the rock surface. This device is described in this paper. Displacement measurements are made in a central measuring hole, since a point of zero displacement, located equidistant between the loaded surface and the upward-pointing anchoring forces, offered a suitable reference point. In this way, the measuring device is also well protected against disturbing variations in temperature. During cyclic loading and unloading, charateristic load/deflection graphs are recorded, which directly demonstrate the deformation properties of the rock, such as the modulus of deformation at different loads, linearity deviation from linearity, as well as hysteresis effects and creep. It is clear that the results of the investigation apply only to the measuring point—the place at which the investigation was carried out. The properties of the rock nearby may vary considerably. The procedure for using this method of investigation for testing improvement measures for turbine foundations is shown in some examples.  相似文献   
118.
Information in the universe evolves according to a nonlinear law, which results from a combination of nonlinear dynamics and quantum theory. The Kolmogoroff-Sinai entropy rate of the Universe evolves in inverse proportion to the temperature. Since the evolution of temperature is known from standard cosmology, the time dependence of the universal entropy rate can be determined and the temporal evolution of the universal information content can be calculated. Information starts growing at the enormous rate of 1044 bits per second from an initial value of at least 2 (seven) bits at Planck time. However, it reaches its contemporary value only if one or more inflationary phases have been passed by the Universe in the course of its evolution.  相似文献   
119.
In the last years more and more often detections of antimicrobially active compounds (“antibiotics”) in surface waters have been reported. As a possible input pathway in most cases municipal sewage has been discussed. But as an input from the realm of agriculture is conceivable as well, in this study it should be investigated if an input can occur via the pathway application of liquid manure on fields with the subsequent mechanisms surface run‐off/interflow, leaching, and drift. For this purpose a series of surface waters, soils, and liquid manures from North Rhine‐Westphalia (Northwestern Germany) were sampled and analyzed for up to 29 compounds by HPLC‐MS/MS. In each of the surface waters antibiotics could be detected. The highest concentrations were found in samples from spring (300 ng/L of erythromycin). Some of the substances detected (e.g., tylosin), as well as characteristics in the landscape suggest an input from agriculture in some particular cases. In the investigation of different liquid manure samples by a fast immunoassay method sulfadimidine could be detected in the range of 1…2 mg/kg. Soil that had been fertilized with this liquid manure showed a content of sulfadimidine extractable by accelerated solvent extraction (ASE) of 15 μg/kg dry weight even 7 months after the application. This indicates the high stability of some antibiotics in manure and soil.  相似文献   
120.
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