Petrographische Untersuchungen des Suevit aus den Bohrungen Deiningen und Wörnitzostheim im Ries von Nördlingen     

Ulrich Förstner 《Contributions to Mineralogy and Petrology》1967,15(4):281-308

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.

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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.

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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.

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

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Der Deutschen Forschungsgemeinschaft danke ich für die finanzielle Unterstützung dieser Arbeit.  相似文献   

灰色系统理论在海堤沉降预测中的应用   总被引：8，自引：2，他引：6  

臧德彦 《测绘工程》1999,8(2):50-54

利用灰色系统理论,对秦山核电站一期海堤沉降进行了预测,以较少的观测样本建立了新陈代谢数列,经后验差检验,观测精度达到一级。由此证明,用ＧＭ（１,１）模型进行预测,建模方便,预测精度高,在大型建筑物变形监测中有较大的实用价值。  相似文献   

Spectroscopic investigation of the chromosphere     

Ulrich Grossmann-Doerth  Marina Von Uexküll 《Solar physics》1973,30(1):71-74

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   

Energy flow and elemental concentrations in the Steina River ecosystem (Black Forest, Germany)     

Giulio P. Genoni  Elisabeth I. Meyer  Andrea Ulrich 《Aquatic Sciences - Research Across Boundaries》2003,65(2):143-157

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   

喀喇沁玻基橄辉岩中的磷酸盐质熔体及磷灰石   总被引：2，自引：0，他引：2  

邵济安  王志海 《岩石学报》2000,16(3):449-453

磷酸盐在本文讨论的坡基橄辉岩中以多种形式产生,有早期结晶的磷灰石斑晶;有熔离的磷酸盐质熔浆液滴;也有晚期穿入橄榄石斑晶的磷酸盐质细脉,表明元素磷活跃在岩浆演化的每一个阶段。磷酸盐质熔浆液滴的存在,说明磷酸盐质熔体可能是由于岩浆的熔离作用而形成的。沿着橄榄石晶格生长石出现的磷酸盐质玻璃细脉则进一步证实地幔中含磷流体不但存在,而且具有很强的活动性。  相似文献   

历史纸质气象档案数字化技术策略初步分析          下载免费PDF全文

兰平  臧海佳 《应用气象学报》2006,17(4):478-482

利用安全扫描和光学字符识别技术实现气象档案数字化是对纸质气象历史档案拯救和开发利用的有效途径。该文在对数字化技术进行调研和试验的基础上, 提出了历史纸质气象档案数字化的建设思路, 针对气象档案记录内容的特点, 对OCR (optical character recognition) 手写体数字识别技术应用进行了分析, 提出了气象档案OCR识别的解决策略, 为业界的纸质气象档案数字化建设提供一种技术思路和有效的技术参考。  相似文献   

Rock Damage and Fluid Transport, Part I     

Georg Dresen  Ove Stephansson  Arno Zang 《Pure and Applied Geophysics》2006,163(5-6):915-916

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Monitoring of atmospheric deposition in European forests and an overview on its implication on forest condition     

Richard Fischer  Volker Mues  Erwin Ulrich  Georg Becher  Martin Lorenz 《Applied Geochemistry》2007

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   

Dating of lower terrace sediments from the Middle Rhine area, Germany     

Sung-Won Choi  Frank Preusser  Ulrich Radtke 《Quaternary Geochronology》2007,2(1-4):137-142

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 (D_e) within the different aliquots. Nevertheless, a substantial number of aliquots from the modern deposits reflect D_e 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 D_e 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 D_e 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   

Imaging Offsets in the Moho: Synthetic Tests using Gaussian Beams with Teleseismic Waves     

Robert L. Nowack  Wang-Ping Chen  Ulrich Kruse  Saptarshi Dasgupta 《Pure and Applied Geophysics》2007,164(10):1921-1936

We carry out a sequence of numerical tests to understand conditions under which rapid changes in crustal thickness can be reliably imaged by teleseismic body waves. Using the finite-difference method over a 2-D grid, we compute synthetic seismograms resulting from a planar P-wavefield incident below the grid. We then image the Moho using a migration scheme based on the Gaussian beam representation of the wavefield. The use of Gaussian beams for the downward propagation of the wavefield is particularly advantageous in certain geologically critical cases such as overthrusting of continental lithosphere, resulting in the juxtaposition of high-velocity mantle material over crustal rocks. In contrast to ray-based methods, Gaussian beam migration requires no special treatment to handle such heterogeneities. Our results suggest that with adequate station spacing and signal-to-noise ratios, offsets of the Moho, on the order of 10 km in height, can be reliably imaged beneath thickened crust at depths of about 50 km. Furthermore, even sharp corners and edges are faithfully imaged when precise values of seismic wave speeds are available. Our tests also demonstrate that flexibility in choices of different types of seismic phases is important, because any single phase has trade-offs in issues such as spatial resolution, array aperture, and amplitude of signals.  相似文献