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31.
32.
Zusammenfassung Nach einer Erläuterung des Begriffes Stockwerktektonik wird über derartige Untersuchungen im südlichen Ruhrkarbon berichtet. Hier lassen sich drei durch fließende Übergänge verbundene tektonische Stockwerke unterscheiden: Das Flözleere ist durch das Vorherrschen tektonischer Formen niederer Größenordnung gekennzeichnet, die sich an bestimmten Stellen summieren. Das nächst höhere Stockwerk zeichnet sich durch eine sanfte Faltung und einige typische Faltenformen aus. Ein weiteres Stockwerk ist in seinem Formenschatz stärker differenziert. Über höhere Stockwerke liegen Untersuchungen vonKukuk, Kienow undSeidel vor. - Der vorliegende Bericht bringt nur Ergebnisse aus dem südlichen Revier; eine Gesamtdarstellung kann damit noch nicht gegeben werden.  相似文献   
33.
Summary UsingCraddock's method of representing the annual temperature variation by a two-term harmonic form fitted to monthly means, the harmonic coefficients of 63 stations in western Europe and around the Mediterranean Sea, as well as the 5-day normals for 24 Mediterranean stations, were computed and tabulated. In addition, some of the harmonic coefficients were charted and isoplethed, showing very distinctly the influence of continentality and topography. These charts, together withCraddock's charts for northern and northwestern Europe, provide fairly complete coverage of Europe and the Mediterranean area.This paper was prepared in the offices of the Technical Support Division of the 2d Weather Wing, United States Air Force, as a matter of routine business. The information contained herein was presented at the 5th Meeting of the Italian Society of Geophysics and Meteorology by Dr.Ingrid Weiss (Genoa: 23–25 April 1957). Since the paper is of general interest to all meteorologists of the Mediterranean area, it is published here with the permission of the originating agency as «Mémoire No. 3 du Centre International de Recherches sur la Météorologie de la Méditerranée (CIRMM)».  相似文献   
34.
This paper discusses the broadscale distribution of some ore deposit types in South America, trying to discern possible relations with major geotectonic features. It does not cover all ore deposits but rather a selection based on available information, genetic types, geographic distribution, and a representation of deposit types which are either abundant or very rare in South America. Included are porphyry copper, zoned copper-zinc-lead-silver, contact-metasomatic, red-bed copper-uranium-vanadium, lead-zinc (including Mississippi Valley type), mercury, tin, pegmatite, carbonatite and alkalic complex, diamond, nickelcobalt-chromite-asbestos-talc, iron, bauxite, tungsten, titanium, uranium, gold, potash and phosphate deposits. Comparisons are made with the distribution of these deposit types in other continents, especially in North America and Africa. This leads to some speculations bearing on theories of ore genesis. The evidence suggests that upper crustal processes predominate in the formation of the majority of ore deposits considered (excepting carbonatites, alkalic complexes and diamond pipes). Also, the relative level of an orogenic belt exposed by erosion seems to be an important factor bearing on the presently known distribution of many ore deposit types. Furthermore, the fact that ore deposits of given types tend to be aligned along the Cordillera in more or less defined belts with changing chemical composition accross the Andes, which partake in all its inflections, and in patterns which are similar in North and South America, indicates that they are either dependent on the distribution of eugeosynclinal vs miogeosynclinal sediments in the original geosynclinal prism, or that their character is related to distance from the major batholitic masses or to shallow stocks and volcanic activity. The indicated correlation with sediment character and evaporites speaks in favor of modem concepts viewing hydrothermal fluids as mainly meteoric but heated and circulated largely by igneous activity. This study raises more questions than it can answer and calls attention to a number of problems requiring further research. From a practical point of view, this investigation reveals several possibilities for future exploration, as well as opportunities for further development of mineral resources in South America. Several countries could probably improve or diversify their mineral production significantly, thus raising the standard of living of their increasing population. Whereas in North America both Canada and the U.S.A. span from east to west the whole range of geological environments, from cratonic to geosynclinal and orogenic, in South America the distribución of countries is essentially either along the Cordillera or over shield areas, a fact of obvious geopolitical implications with regard to mineral resources.  相似文献   
35.
The Southern Venn-Stavelot Massif is characterized by Ordovician and Devonian rocks very rich in manganese and aluminum, which are attacked by a low grade regional metamorphism. The assemblages 1 (phengite, paragonite, chlorite, chloritoid, garnet, quartz, hematite, rutile) and 2 (phengite, paragonite, chlorite, kaolinite (andalusite, pyrophyllite), garnet, quartz, hematite, rutile) are of basic interest for the formation of chloritoid. As the two rock types are isofaciell and quasi-identical in chemistry except for the iron oxides, there is clear evidence for the influence of on the chloritoid formation at its lower p-T stability limit. This can be shown by a discussion of the phase relations of chloritoid, garnet, kaolinite, chlorite and phengite in respect to the oxidation ratio mol 2 Fe2O3x 100/2 Fe2O3+ FeO of the host rocks. Especially chloritoid and chlorite change their chemistry in a characteristic way with rising oxidation ratio in getting richer and richer in manganese and magnesium (chloritoid) and magnesium (chlorite). A simultaneous increase in trivalent iron in these phases is supposed. At an oxidation ratio of 85–90 the stability limit of chloritoid is reached. The increasing substitution of manganese and magnesium up to this limit should have a stabilizing effect. In a rough estimate the oxygen partial pressure is supposed to be in the order of 10−10 atm at the stability limit of chloritoid assuming a temperature of metamorphism between 360–400° C. Rocks with oxidation ratios between 90 and 100 are characterized by the presence of kaolinite. If the oxidation ratio is still higher (all iron as Fe3+, parts of the manganese in the trivalent state), the rocks belong to assemblage 3 (phengite, paragonite, chlorite, viridine, (kaolinite), (garnet), quartz, hematite, braunite, rutile). Dedicated to Prof. Dr. K. Jasmund at his 60. birthday.  相似文献   
36.
Zusammenfassung In den Bohrungen Deiningen (D.) und Wörnitzostheim (W.) im Nördlinger Ries wurde unter tertiären Seesedimenten eine 40 m bzw. 70 m mächtige Suevitabfolge aufgeschlossen. Diese Breccie, bestehend aus zertrümmertem kristallinem Grundgebirge mit verschiedenen Anzeichen einer Stoßwellenmetamorphose und aus Glasbomben, wurde mineralogisch und petrographisch untersucht.Korngrößenanalysen zeigen in beiden Profilen eine allmähliche Zunahme des Mediandurchmessers von oben nach unten (D.: 0,1···0,4 mm; W.: 1···6 mm). Die Kornverteilungskurve von W. ist bimodal; das Hauptmaximum wird überwiegend aus grobkörnigen Gesteinsgläsern gebildet, ein kleineres Maximum liegt bei 0,2–0,6 mm und enthält bevorzugt Grundgebirgseinschlüsse.Das Verhältnis von Gesteinsgläsern: Kristallinkomponenten beträgt in D. etwa 30 70, in W. 60 40. Der Suevit von W. enthält durchschnittlich 28% Porenraum und 1–2% Neubildungen; seine Glassubstanz ist überwiegend frisch. Im Suevit von D. sind die Gläser sekundär zersetzt und bedingen höhere Porenvolumina (34–36%) und eine stärkere Verwitterungsneubildung (6–10%; Montmorillonit, Montmorillonit-Illit-Wechsellagerung, Karbonate und Analcim).Einzelminerale in der Kornfraktion 0,063–0,125 mm verteilen sich bei den Leicht-mineralen (d<2,96 g/cm3; Neubildungen nicht berücksichtigt) auf Feldspäte (D.: 56%; W.: 44%), Quarz (D.: 32%; W.: 28%), Biotit (D.: 5%; W.: <1%), Hornblende (D.: 2%; W.: -) und Gläser (D.: 3%; W.: 27%); der Anteil der Schwerminerale beträgt in D. 3–4% (Biotit, Opakes — Hornblende, Granat, Turmalin), in W. 0,5–0,8% (Opakes, Zirkon — Biotit, Rutil).Die chemische Zusammensetzung der Suevit- und Glasproben von W. ist dem granodioritischen Magmentyp ähnlich; die Suevitproben von D. weisen höhere Alkaligehalte auf.
Underlying miocene lake sediments, suevite was found in the drill holes of Deiningen (D.) and Wörnitzostheim (W.), 40 meters and 70 meters thick, respectively. This breccia, containing glass and shattered crystalline rocks, in different stages of shock metamorphism, was examined by mineralogical and petrographical methods.In the two suevite profiles medians of grain size distributions gradually increase from top to bottom (D.: 0,1···0,4 mm; W.: 1···6 mm). The grain size distributions of W. are bimodal; the first maximum is mainly formed by coarse grained glass, the second (smaller) maximum (0,2···0,6 mm) contains crystalline components. The ratio of melted rocks: crystalline components is 3070 at D. and 6040 at W. Suevite from the latter locality has a total porosity of 28% (average) and contains 1–2% autigenic minerals; the glasses are mostly fresh. In the D. suevite decomposition of the glass has produced higher porosities (34–36%) and more autigenic minerals (6–10%: montmorillonite, mixed-layer minerals montmorillonite-illite, carbonates, analcime).Mineral composition was determined for the grain sizes from 0,063 to 0,125 mm. The light minerals (d<2,96 g/cm3, without autigenic minerals) comprise: feldspars (D.: 56%; W.: 44%), quartz (D.: 32%; W.: 28%), biotite (D.: 5%; W.: < 1%), hornblende (D.: 2%; W.: -) and glass (D.: 3%; W.: 27%); heavy-mineral content is 3–4% at D. (biotite, opaque minerals — hornblende, garnet, tourmaline) and 0,5–0,8% at W. (opaque minerals, zircon — biotite, rutile).The chemical composition of suevite and glass samples from W. is similar to granodiorite type rock. The suevite of D. contains more potassium and sodium.


Meinem verehrten Lehrer, Herrn Prof. Dr. W. v. Engelhardt, danke ich für die Überlassung des Themas und alle Förderung meiner Arbeit. Für fördernden Rat danke ich ferner den Herren Dr. F. Lippmann und Dr. D. Stöffler.

Der Deutschen Erdöl AG, insbesondere Herrn Prof. Dr. F. Hecht, danke ich für die Überlassung der Bohrkerne von Deiningen.

Der Deutschen Forschungsgemeinschaft danke ich für die finanzielle Unterstützung dieser Arbeit.  相似文献   
37.
The line profile of H as emanating from the interior of supergranular cells was measured at sin = 0, 0.6, 0.8 and 0.9. The measurements are described and the results presented.Mitteilung aus dem Fraunhofer Institut Nr. 117.  相似文献   
38.
Considering food web energetics and elemental cycling together allows the testing of hypotheses about the coevolution of biological systems and their physical environment. We investigated the energy flow and the distribution of 25 elements in the Steina River.¶We constructed an annual energy flow network and estimated the emergy ("embodied energy" that includes all the energy involved in a process) contributions of resources sustaining the system. Furthermore, we measured the concentration of various macronutrients, essential elements, and heavy metals in the physical environment and trophic compartments. Finally, we examined the hypothesis of a positive relationship between the "rarity" of an element and its tendency to bioaccumulate. To do so, we used transformity, the relative energy input required to sustain a compartment's net production or the concentration differential of an element between the living community and the physical environment.¶The resulting energy flow network is one of the most complete available for streams. In the Steina, over 99% of the energy input is transported through the system without being processed. Dissolved inorganic matter and sunlight are the largest inputs, but uptake efficiency is much higher for dissolved and particulate organic matter. Transformities of trophic compartments and elements span 6 to 7 orders of magnitude.¶The tendency to bioaccumulate was as predicted for most elements, with macronutrients showing no accumulation and heavy elements accumulating in high-transformity compartments. However, Na and K were found at highest concentrations in consumers, and Pb, Ga, and Cd in algae. Improved estimates may become possible as more knowledge is available on ecosystem flows. We suggest further ways of testing hypotheses about strategies of element processing.  相似文献   
39.
Forest conditions in Europe have been monitored over 20 years jointly by the International Cooperative Programme on Assessment and Monitoring of Air Pollution Effects on Forests (ICP Forests) and the European Union (EU). Maps for mean bulk SO4, NO3 and NH4 deposition at around 400 intensive monitoring plots in the years 1999–2001, as well as time trends for the period 1996–2001, are presented. Mean bulk SO4 deposition at 169 plots mostly located in central Europe decreased from 7.4 to 5.8 kgS ha−1 a−1. Mean NH4 bulk deposition decreased from 6.2 to 5.3 kgN ha−1 a−1. Nitrate bulk deposition fluctuated around 5 kgN ha−1 a−1. On average, throughfall deposition was considerably higher than bulk deposition. Time trends for mean tree crown defoliation as an overall indicator for forest condition show a peak in the mid 1990s for most of the monitored main tree species and a recent increase for the years 2003 and 2004. Multivariate linear regression analyses show some significant relations between deposition and defoliation. These relations depend on the tree species and site characteristics. Effects of deposition are moderated by the influence of biotic stress factors such as insects and fungi and by abiotic stress factors, such as weather.  相似文献   
40.
Modern and known-age Pleistocene fluvial sediments were investigated by optical dating of quartz to test the suitability of the approach for dating deposits from the deeply incised Middle Rhine Valley. Samples from modern flood sediments revealed skewed distributions indicating different residual levels of equivalent dose (De) within the different aliquots. Nevertheless, a substantial number of aliquots from the modern deposits reflect De values close to zero. For the Pleistocene samples, optical ages are in general consistent with age control given by the presence of the Laacher See Tephra and radiocarbon dating. However, some samples overestimate the known age by a few thousand years when using the arithmetic mean. This is apparently explained by including aliquots in the determination of mean De where the optical signal was incompletely bleached at deposition. The most difficult issue in this context is identifying a suitable approach that can distinguish between the variability of De due to partial bleaching and microdosimetry. However, even when considering these limitations it appears that optical dating will by a quite suitable method to date Pleistocene sediments from such a complex fluvial environment, especially when focusing on a precision scale beyond a few thousand years.  相似文献   
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