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531.
Markus Båth 《Tectonophysics》1980,66(4):T11-T18
Based on a combination of instrumental and macroseismic data, a method for calculating maximum seismic intensities is developed and applied to Sweden for the period 1951–1976. The method is particularly useful for areas with a low seismicity and a sparse population. Tectonophysical and engineering aspects on the resulting map are discussed. 相似文献
532.
Dr. Hermann Harder 《Contributions to Mineralogy and Petrology》1954,4(1-2):54-66
Ohne ZusammenfassungHerrn Professor Dr.Carl W. Correns zur 60. Geburtstag gewidmet. 相似文献
533.
Dr. Markus Båth 《Pure and Applied Geophysics》1959,43(1):108-130
Summary A review is given of the present (1959) seismological stations in Sweden, i.e. Uppsala, Kiruna, Skalstugan, and Göteborg, as well as of older stations, which are no longer in operation, i.e. Vassijaure, Abisko, and Lund, including all pertinent information. The disturbing effect of the loose ground at Lund in distinction from the four first-mentioned stations is clearly demonstrated. The very good ground at Uppsala, Kiruna, Skalstugan, and Göteborg, together with the use of modern equipment of high magnification has made these stations, especially Uppsala and Kiruna, very sensitive. This is obvious from the number of recorded earthquakes. The method of time measurements, including direct recording of time signals, is described, and means to reach a high time accuracy are outlined, including the recommendation to use quartz clocks. Long-period (0.5–2 min) disturbances on the long-period Benioff combinations were mainly due to air currents in the seismometer room and were eliminated by providing the seismometers with special covers. The method of ground amplitude determinations is outlined, especially for the Benioff instruments, and typical magnification curves are given. Comparisons of ground amplitudes from simultaneous records of BenioffE, N and WiechertE, N and of BenioffZ and GrenetZ have been made. The amplitude comparison between Benioff and Wiechert has given a new estimate of the effect of friction (especially of the recording pen against the paper) in the Wiechert apparatus.
Zusammenfassung Eine Übersicht sowohl von den gegenwärtigen (1959) seismologischen Stationen in Schweden, d.h. Uppsala, Kiruna, Skalstugan und Göteborg, als auch von früheren Stationen, die nicht mehr im Betrieb sind, d.h. Vassijaure, Abisko und Lund, wird gegeben. Die störende Wirkung des lockeren Bodens in Lund zum Unterschied gegen die vier erstgenannten Stationen wird deutlich hervorgehoben. Der sehr gute Untergrund in Uppsala, Kiruna, Skalstugan und Göteborg und die Verwendung moderner Apparate hoher Vergrösserung haben diese Stationen, besonders Uppsala und Kiruna, sehr empfindlich gemacht. Dieser Umstand geht aus der Anzahl registrierter Beben hervor. Die Methode der Zeitmessungen (direkte Registrierung der Zeitsignale einbegriffen) wird beschrieben, und Massnahmen eine hohe Zeitgenauigkeit zu erreichen werden erwähnt, die auch die Verwendung von Quarz-Uhren umfassen. Langperiodische Störungen (Perioden 0.5–2 Min) auf den langperiodischen Benioff-Registrierungen waren hauptsächlich durch Luftströmungen im Seismometerraum verursacht und wurden durch spezielle Kappen über den Seismometern eliminiert. Die Methode der Bestimmung von Boden-Amplituden wird beschrieben, hauptsächlich für die Benioff-Instrumente, und typische Vergrösserungskurven sind gegeben. Vergleichungen der Bodenamplituden von parallelen Registrierungen von BenioffE, N und WiechertE, N und von BenioffZ und GrenetZ sind ausgeführt worden. Die Amplitudenvergleichung zwischen Benioff und Wiechert hat eine neue Schätzung des Einflusses der Reibung (speziell vom Schreibfeder gegen das Papier) im Wiechert-Seismographen gegeben.相似文献
534.
Summary Continental dispersion curves for Love and Rayleigh waves have been determined by means of the Uppsala seismograph records for three earthquakes near the south coast of Turkey in April, 1957. To the authors' knowledge this is the first time dispersion curves have been determined for a relatively homogenous path across the whole of continental Europe and covering a good range of periods, namely from 3 to 86 sec for Love waves and from 5 to 61 sec for Rayleigh waves. The dispersion curves obtained are relevant to determinations of the average structure along the path traversed in particular, and to determinations of crustal structure of the European continent in general.
Zusammenfassung Kontinentale Dispersionskurven für Love-und Rayleigh-Wellen wurden vermittels Registrierungen an der Station Uppsala von drei Erdbeben in der Nähe der Südküste der Türkei im April 1957 bestimmt. Soweit es den Autoren bekannt ist, wurden damit erstmalig Dispersionskurven für einen relativ homogenen Weg über das gesamte kontinentale Europa mit einem beträchtlichen Periodenbereich, der 3 bis 86 Sek für Love-Wellen und 5 bis 61 Sek für Rayleigh-Wellen umfasst, ausgearbeitet. Die erhaltenen Dispersionskurven haben ihre Bedeutung in der Festlegung der mittleren Krustenstruktur entlang dem durchlaufenen Wellenweg und überhaupt in der Festlegung der Krustenstruktur im Bereich des europäischen Kontinents.相似文献
535.
Samantha Palmer Ian Walker Markus Heinrichs Geoffrey Scudder 《Journal of Paleolimnology》2002,28(4):469-490
Stratigraphic analysis of fossil chironomid head capsules wasperformed at North Crater Lake and Lake of the Woods, located at treeline (2250m) in the Ashnola region of southernmost British Columbia. Priorto 10,000 yr BP, cold conditions were indicated by the lack oftemperate taxa and the presence of cold-stenotherms. The abundance anddiversity of warm-adapted taxa (e.g., Dicrotendipes,Microtendipes, Polypedilum and Cladopelma)increased rapidly after 9500 yr BP, whereas taxa indicative ofcold conditions disappeared. Beginning prior to deposition of the Mazama ash(6730 ± 40 yr BP), several warm-adapted taxa decreasedin abundance. Mid- to late-Holocene assemblages (ca. 4500yr BP to present) indicated continued cooling as revealed by afurther reduction in diversity and abundance of warm-adapted taxa atboth lakes, and the reappearance of cold-stenotherms in Lake of theWoods. Diversity changes in the cores paralleled the inferred climatic changes.Diversity was low during the late-glacial, increased in theearly-Holocene, and declined after 5400 yr BP.To quantitatively infer past climatic changes, a newweighted yphen;averaging partial-least-squares (WA-PLS)model was developed and applied to the fossil midge data. The quantitativereconstructions revealed late-glacial mean July air temperatures rangingfrom about 8 to 10°C. Summer air temperatures were highest inthe early Holocene (13 to 17°C), gradually decreasing by about3°C through the mid- to late-Holocene. 相似文献
536.
Depth profiles of dissolved zinc were measured monthly over one year in Lake Greifen, a eutrophic lake. The concentrations are in the range 10–40 nM and show systematic variations over time and depth. Due to the increased binding to particles and subsequent settling, concentrations of zinc in the epilimnion decrease during summer stagnation. Clear correlations between Zn and major nutrients (P, Si) are, however, not observed in the water column. No accumulation of Zn occurs in the anoxic hypolimnion. The Zn sedimentation is related to the sedimentation of algae and of manganese oxide. A mass-balance calculation shows that 87% of the Zn input is retained in the sediments of Lake Greifen. 相似文献
537.
538.
Dr. Hermann Harder 《Contributions to Mineralogy and Petrology》1951,2(5):455-476
Zusammenfassung Die eisenoolithischen Lias--Erze der Lagerstätten Echte, Markoldendorf und Holtensen wurden chemisch, spektralanalytisch, röntgenographisch und optisch untersucht.Wie schonC. W. Correns undW. v. Engelhardt zeigten, gestattet die röntgenographische Methode eindeutige Aussagen über den Mineralbestand der feinkörnigen sedimentären Eisenerze.Petrographisch unterscheiden wir drei Erzsorten: Grüne Chamositerze, rote Hämatiterze und braune Nadeleisenerze. Die Minerale der Chamositerze sind: Chamosit, Siderit und Kalkspat neben geringen Mengen von Quarz und Pyrit. Hämatiterze bestehen aus Hämatit und Calcit neben geringen Mengen Chamosit und Siderit. 相似文献
539.
540.
More than half of the surface sediments covering the continental shelves are sandy, which may permit substantial sub-seafloor pore water advection. Knowledge of sediment permeability is required for quantifying advection and associated solute transport, but studies of marine sediments typically report grain size analyses rather than permeability. Here data from 23 studies were examined to determine the range in permeabilities reported for sublittoral marine sands and to assess the utility of permeability–grain size relationships in this setting. In the resulting database, the permeability of small (∼30 cm) undisturbed cores collected from the sea floor all fell between 2 × 10−12 and 4 × 10−10 m2, a range where advective transport induced by wave and current action should be pervasive. The range in grain size was very similar for near-shore (<10 m water depth) and continental shelf samples (>10 m water depth), but the permeability of the continental shelf samples was consistently lower for the same median grain size. Empirical permeability–grain size relationships generated a poor fit (r2 = 0.35) for the aggregate data, but separate relationships for near-shore and continental shelf samples were significantly better, r2 = 0.66 and 0.77, respectively. Permeability–grain size relationships thus may be useful for sublittoral sands, but a larger database needs to be accumulated before reliable fit parameters and variability can be predicted. Thus it is recommended that permeability be routinely determined when characterizing sedimentological properties of marine sand deposits. Concurrent determinations of sediment bulk density and porosity may further improve estimates of permeability. 相似文献