Die entwicklung der Landwirtschaft in den bantugebieien von Süd- und Südwestafrika: Magura,W. (1970): Afrika-Forschungsbericht Nr. 26, Afrika-Studienstelle des IFO-lnstituts. 211 S., 4 Karten. München: Weltforum Verlag. DM 20,-     

Erwin Mai 《Geoforum》1974,5(3):92-93

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Interaction of organic compounds with calcium carbonate-II. Organo-carbonate association in Recent sediments     

Erwin Suess 《Geochimica et cosmochimica acta》1973,37(11):2435-2447

Surface area measurements as well as organic carbon, nitrogen and phosphorus analyses on various grain size fractions of carbonate mud samples confirm that in natural environments of carbonate deposition, surface sorption processes take place which are similar to those described earlier for dissolved organics and artificially suspended calcite particles in both seawater and synthetic solutions.The specific surface area of the sediment increases from 1.8m²/g for the coarse-grained fraction to 12.5 m²/g for the fine material; likewise organic carbon, nitrogen and phosphorus increase with increasing surface area so that there are 1.20 mg C, 0.175 mg N and 0.06–0.20 mg P associated with every square meter of carbonate surface irrespective of the mineralogy of the sediment particles.It appears that the organic matter in these sediments is similar in composition, structure and quantity to the organic layers produced in sorption experiments. With their apparently defined structure and ubiquitous nature, these layers could determine the mineralogy and orientation of submarine carbonate cement or could even be a prerequisite to calcification in general.  相似文献   

The metamorphic evolution of migmatites from the Ötztal Complex (Tyrol,Austria) and constraints on the timing of the pre-Variscan high-T event in the Eastern Alps     

Werner F. Thöny  Peter Tropper  Friederike Schennach  Erwin Krenn  Friedrich Finger  Reinhard Kaindl  Franz Bernhard  Georg Hoinkes 《Swiss Journal of Geoscience》2008,101(1):111-126

Within the Ötztal Complex (ÖC), migmatites are the only geological evidence of the pre-Variscan metamorphic evolution, which led to the occurrence of partial anatexis in different areas of the complex. We investigated migmatites from three localities in the ÖC, the Winnebach migmatite in the central part and the Verpeil- and Nauderer Gaisloch migmatite in the western part. We determined metamorphic stages using textural relations and electron microprobe analyses. Furthermore, chemical microprobe ages of monazites were obtained in order to associate the inferred stages of mineral growth to metamorphic events. All three migmatites show evidence for a polymetamorphic evolution (pre-Variscan, Variscan) and only the Winnebach migmatite shows evidence for a P-accentuated Eo-Alpine metamorphic overprint in the central ÖC. The P-T data range from 670–750 °C and < 2.8 kbar for the pre-Variscan event, 550–650 °C and 4–7 kbar for the Variscan event and 430–490 °C and ca. 8.5 kbar for the P-accentuated Eo-Alpine metamorphic overprint. U-Th-Pb electron microprobe dating of monazites from the leucosomes from all three migmatites provides an average age of 441 ± 18 Ma, thus indicating a pervasive Ordovician-Silurian metamorphic event in the ÖC.  相似文献   

A field trial for in-situ bioremediation of 1,2-DCA   总被引：2，自引：0，他引：2  

Mark Dyer  Erwin van Heiningen  Jan Gerritse 《Engineering Geology》2003,70(3-4):315-320

Historic spillages of chlorinated hydrocarbons at a vinyl chloride plant in the Rotterdam Botlek area in The Netherlands have lead to contamination of the underlying aquifer. The principal contaminant is 1,2-dichloroethane (1,2-DCA). The contamination is temporarily contained by a pump-and-treat system. A field trial was carried out to investigate the feasibility of treating the dissolved phase of 1,2-DCA via reductive dechlorination by injection of an aqueous solution of methanol, ammonium chloride and sodium chloride into the confined aquifer using an array of eight boreholes. Biodegradation of 1,2-DCA was localised. This was attributed to limited mixing of the carbon substrate within the test zone. In addition, clogging of recharge wells complicated groundwater circulation.  相似文献   

Die Mikroseismik und ihre Anwendung zum Abschätzen der Dicke der Kontinentalschollen     

Dozent Dr. Erwin Hardtwig 《Pure and Applied Geophysics》1949,14(3-4):203-224

Zusammenfassung An Hand einiger Wetterlagen mit besonders starker Mikroseismik wird der Verlauf von Amplituden und Perioden in Stuttgart verfolgt. Das Gesetz der Abhängigkeit zwischen Periode und Amplitude wird empirisch ermittelt, das Periodenspektrum gezeichnet. Die am häufigsten auftretende Periode wird zur Berechnung der Dicke der schwingenden Schicht benutzt unter der Annahme, dass diese Schicht mit ihrer Unterlage lose verbunden ist und die Art der Schwingungen sich nicht wesentlich von Rayleighwellen unterscheidet. Es ergibt sich so der theore tische Zusammenhang zwischen Periode und Amplitude einerseits und der Schichtdicke andrerseits. Sie beträgt für Norwegen etwas über 40 km.

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Summary With the help of several weather-situations with particularty violent microseism the progress of amplitudes and periods as perceived at Stuttgart is examinated. The law of dependency between period and amplitude is found empirically, the spectrum of periods is drawn up. The period, which occurs most frequently is used for calculating the thickness of the swinging layer as this layer is supposed to be in loose connection with its support and as the sort of oscillations is not essentially different from Rayleight waves. Thus there is found the theoretical connection between periods and amplitudes and, on the other side, the thickness of layer of something more than 40 km for Norway.

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Bemerkungen zur Zwillingsbildung bei Plagioklasen     

Dr. Erwin Nickel 《Contributions to Mineralogy and Petrology》1949,2(1-2):176-188

Ohne Zusammenfassung  相似文献   

An Algorithm to Determine the Slope of the Spectral Absorption of Colored Dissolved Organic Matter (CDOM) and Detritus     

Suresh Thayapurath  Albertina Balbina Dias  Erwin J. A. Desa  Arvind Sahay 《Journal of the Indian Society of Remote Sensing》2018,46(4):625-631

A simple method to determine the slope of spectral variations of combined absorption of the colored dissolved organic matter and detritus (CDM) is presented. This method uses the slope of total absorption spectrum excluding contribution of waters in lieu of slope for the CDM. The errors in slopes using the new method decreased with increase in contributions of CDM to the total absorption. The relative errors were less than 10% when CDM contributions were above 60% and even at very low contributions of CDM of 25%, errors in the slopes were less than 40%. For estuarine and coastal waters rich in CDM, the errors in the slopes for CDM were less than 10% using this simple method. Absorption of CDM derived using the slope with the new method in a semi-analytical algorithm QAAV6 showed improved performance with RMSE of 0.07, 0.0119 and 0.0027 at 405, 555 and 665 nm respectively and with R² > 0.95 at all spectral range. The method provided values of spectral absorption due to CDM with fewer errors when validated with the satellite derived data from MODIS and SeaWiFS. This method to determine the slope of CDM could be easily implemented in any model, as it was very generic in nature, simple, did not involve any mathematical model and avoids empirical methods. Since the method is also independent of any specific bands, it can be used for most ocean color satellites. Considering the performance of this new method and applicability for most water types, it was considered as a better option to derive the slope of CDM than using a constant value or deriving the slope with empirical method.  相似文献   

Magnetic signature of hydrocarbon-contaminated soils and sediments at the former oil field H?nigsen, Germany     

Moti L. Rijal  Katharina Porsch  Erwin Appel  Andreas Kappler 《Studia Geophysica et Geodaetica》2012,56(3):889-908

Magnetic properties of hydrocarbon (HC) containing soils and sediments from two sites (Site A and B) of the former oil-field H?nigsen were analyzed in order to determine whether magnetic methods can be employed to delineate HC contamination of soils and sediments. Magnetic parameters such as magnetic susceptibility and induced isothermal remanent magnetizations, as well as soil and sediment properties such as pH, iron content and water content, HC content and most probable number counts of iron-metabolizing microorganisms were determined. The magnetic concentration-dependent parameters for HC contaminated samples were 25 times higher in soils from Site A than in sediment samples from Site B. However, at Site B the magnetic susceptibility was still four times higher in comparison to lithologically similar non-contaminated sediment samples from a third Site C. Newly formed magnetite containing mainly single domain particles was responsible for the magnetic enhancement, whereas superparamagnetic grains represented only a minor component. Site A had an acidic pH compared to neutral pH at Site B, and a higher crystalline and bioavailable total iron content. Nevertheless, Site B samples contained significant numbers of both iron(II)-oxidizing and iron(III)-reducing microorganisms indicating that microbial iron cycling might have taken place at this site and potentially played a role for iron mineral transformation, including magnetite (trans)formation. The content of total non-polar hydrocarbons (TNPH) at Site A was one order of magnitude higher than at Site B. Only at Site A magnetic susceptibility correlated well with TNPH. Our results demonstrate that HC contaminated samples had an enhanced magnetite content compared to non-contaminated soils and sediments. Therefore, magnetic methods may provide a quick and cost-effective way to assess HC contamination in soils and sediments. However, more field sites and laboratory investigations are needed to reveal the complex nature of the processes involved.  相似文献   

Environmental mechanism of magnetic susceptibility changes of lacustrine sediments from Lake Hulun, China   总被引：1，自引：0，他引：1  

HU Shouyun  WANG Sumin  Erwin Appel  JI Lei 《中国科学D辑(英文版)》2000,43(5):534-540

The changes of magnetic susceptibility(κ) are correlated with those of corresponding sedimentological, geochemical, mineralogical and biological results, which verifies thatκ can be taken as one of the environmental proxies. However, usually the exact origin of magnetic signal is poorly understood, and is difficult to relate with the environmental evolution. Magnetic properties of material derived from the catchment and sedimentary environment may affect the accumulation, preservation, or authigenesis and diagenesis of magnetic minerals. In the Lake Hulun region in Inner Mongolia, it is found that muddy sediments, deposited during high water level period (corresponding to humid climate), have comparatively highκ values. In contrast, the sandy sediments, deposited during low water level period (corresponding to arid climate), have lowκ values. Detailed rock magnetic investigation confirms that detrital magnetite derived from volcanic rocks in the catchment exists in both muddy and sandy sediments. During high water level period, secondary ferrimagnetic iron sulphide was produced in muddy sediments under relatively reductive conditions. Ferrimagnetic iron sulphide, coexisting with detrital magnetite, predominates the magnetic properties of muddy sediments, resulting in increasingκ. This paper reveals the significance of authigenic ferrimagnetic iron sulphide produced after sediment deposition.  相似文献   

The HST/ACS Coma Cluster Survey – V. Compact stellar systems in the Coma Cluster     

J. Price  S. Phillipps  A. Huxor  N. Trentham  H. C. Ferguson  R. O. Marzke  A. Hornschemeier  P. Goudfrooij  D. Hammer  R. B. Tully  K. Chiboucas  R. J. Smith  D. Carter  D. Merritt  M. Balcells  P. Erwin  T. H. Puzia 《Monthly notices of the Royal Astronomical Society》2009,397(4):1816-1835

The Hubble Space Telescope /Advanced Camera for Surveys ( HST /ACS) Coma Cluster Treasury Survey is a deep two-passband imaging survey of the nearest very rich cluster of galaxies, covering a range of galaxy density environments. The imaging is complemented by a recent wide field redshift survey of the cluster conducted with Hectospec on the 6.5-m Monolithic Mirror Telescope (MMT). Among the many scientific applications for these data is the search for compact galaxies. In this paper, we present the discovery of seven compact (but quite luminous) stellar systems, ranging from M32-like galaxies down to ultra-compact dwarfs (UCDs)/dwarf to globular transition objects (DGTOs).
We find that all seven compact galaxies require a two-component fit to their light profile and have measured velocity dispersions that exceed those expected for typical early-type galaxies at their luminosity. From our structural parameter analysis, we conclude that three of the samples should be classified as compact ellipticals or M32-like galaxies, and the remaining four being less extreme systems. The three compact ellipticals are all found to have old luminosity weighted ages (≳12 Gyr), intermediate metallicities  (−0.6 < [Fe/H] < −0.1)  and high [Mg/Fe] (≳0.25).
Our findings support a tidal stripping scenario as the formation mode of compact galaxies covering the luminosity range studied here. We speculate that at least two early-type morphologies may serve as the progenitor of compact galaxies in clusters.  相似文献