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1.
The development of immunodetection method of 2, 2-Bis (4-chlorophenyl) acetic acid (DDA), the decomposition product of organochlorine insecticide DDT, was performed in this study. DDA was conjugated with bovine serum albumin (BSA) and ovualbumin (OVA) for the use of immunogen to produce antibodies and coating ligands to measure the titration level of antibody and the displacement of free analytes. Evaluation of the antisera by antibody capture assay showed that the antibody titer of antisera raised against DDA-OVA was higher than 1 : 80000. Using 5#PAb, an indirect competitive enzyme immunoassay was developed for measurement of DDA. The working range for quantitative measurement of DDA and the quantitative limit for DDA were estimated to be 2.5-2000 ng/mL and 2.5 ng/mL for seawater, 12.5 ng/g for shellfish, respectively.  相似文献   

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Conceptual geological repositories are generally used for disposing spent nuclear wastes containing both high and low level of nuclear radiation and heat. Due to its long-lasting effect, it is imperative to analyze its long-term effect on the surrounding rock. Before analyzing radiation and thermal effect, it is important to have structurally stable cavern because designing an opening in rock is a more difficult problem than designing the structure made of steel. Underground rocks are under stress because of the weight of the overlying rock, and in addition, an underground opening will produce a stress concentration and stress relaxation in the surrounding rock. If the induced stress in the surrounding rock exceeds its strength, the opening will fail either by fracturing or by deforming more than the tolerable limit. In this paper, the stability of four different shapes of excavation has been examined for conceptual geological repositories in Indian context. This has been done using equivalent continuum numerical model which has been incorporated in the commercial finite difference code-FLAC-3D. Effects of opening shapes on stress distribution, subsidence of crown and side wall, and their stability have been analyzed and discussed. The validation of FLAC3D software for its applicability in conceptual underground geological repositories has been done with a published literature.  相似文献   

3.
In geosciences the necessity of combining geological and geophysical information as well as applying tools for designing 3D geological and geophysical models is well accepted. Nevertheless, in most cases this demand is only put into practice by file transfer between the applications. The creation of a common 3D model is complicated by the inflexible handling of new and reinterpreted data and by changing applications, heterogeneous operating systems and/or hardware platforms. We present a new approach for a component based GIS which is coupled with an object oriented database management system. The original data, as well as the derived data and the 3D models, are stored in the extensible database. Geological and geophysical 3D modeling tools have direct access to the database via the Common Object Request Broker Architecture (COREA). By this means, we obtained both the integration of the software components and independence from changing software applications and changing platforms, finally resulting in an interoperable 3D GIS.  相似文献   

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Zusammenfassung Die Sandsteine und Eisenoolithe im Schwäbischen Jura sind im allgemeinen unvollständig verkittet.An der Eisenerzlagerstätte von Geislingen (Steige), einem etwa 2 m mächtigen, langgestreckten Eisenoolithkörper im Oberen Braunen Jura, sind Verkittungserscheinungen besonders auffallend und wurden eingehend untersucht.Die verkitteten Teile können überall im Flözprofil auftreten, insgesamt ist die Verkittung aber oben ausgedehnter als unten. Es wird der Nachweis geführt, daß der Kalkzement primär ± homogen im Profil verteilt war und bei der diagenetischen Mobilisierung vorzugsweise nach oben gewandert ist. Für die Sandsteinhorizonte des Braunen Jura und z. T. des Schwarzen Jura gilt ähnliches.Da der unverkittete Oolith im Korngefüge Setzungserscheinungen zeigt, der verkittete dagegen nicht, läßt sich die Zeit der Verkittung als frühdiagenetisch angeben.Es wird angenommen, daß die Mobilisierung des Kalkzements im Rahmen der Setzungsentwässerung der liegenden Tonschichten erfolgte.Durch Wechsel von Zementation und Erosion ist am Dach des Lagers eine konglomeratische Schicht entstanden. Die Entstehung der konkretionär entstandenen Konglomeratkomponenten wird zu den Verkittungsvorgängen im Flöz in Beziehung gesetzt.  相似文献   

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Zusammenfassung Silurische Riffe von Gotland wurden im Detail untersucht. Es fand Biohermbildung in einem warmen, untiefen, epikontinentalen Flachmeere statt. Verschiedene Typen von Riffen werden beschrieben. Unterschiede zu den heutigen Riffen, dem heutigen reef complex, und den Riffen geosynklinaler Faziesbereiche gegenüber werden diskutiert.  相似文献   

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Summary Early tentative hypotheses, that regional metamorphism may be genetically associated with the formation of mineral deposits are now reasonably confirmed, and the class of metamorphogenic mineral deposits is widely accepted. Two end member models define a range of possibilities occurring in nature: the prograde devolatilization model, and the retrograde leaching model. In the first, the mineralizing fluids are thought to have been generated and to have acquired their solute content within source rocks undergoing prograde metamorphism. Then they flow towards lower pressure zones, possibly accompanied by further reactions with country rocks. Finally, changes in the chemical or physical environment along the flow conduits potentially induce mineral precipitation. Retrograde leaching occurs after peak metamorphism, when a still-hot metamorphic complex is flooded and cooled by waters from outside; this will normally happen during uplift and extensional tectonics, and the resulting convection cells are open to the surface. Metamorphogenic deposits cannot be recognized as such in the field, where they appear as examples of epigenetic hydrothermal mineralization. Only the application of a broad spectrum of laboratory methods allows a correct genetic classification. It is expected that future research will increasingly quantify the evolution of metamorphic terranes through time, similar to modern basin analysis in petroleum geology.
Das Erkenen metamorphogener Lagersätten-eine Einleitung
Zusammenfassung Frühe Beobachtungen über enge Zusammenhänge zwischen regionaler Metamorphose und Lagerstättenbildung wurden in jüngerer Zeit bestätigt, so daß die Klasse der metamorphogenen Lagerstätten nunmehr nahezu gesichert ist. Zwei verschiedene genetische Modelle bilden die Endglieder eines in der Natur vorkommenden Spektrums solcher Lagerstättenbildung: das Modell der prograden Devolatilisierung und das Modell einer retrograden Laugung. Im ersten Fall wurden die lagerstättenbildenden Fluide innerhalb eines Gesteinskörpers gebildet, während dieser eine prograde Metamorphose erlitt; gleichzeitig nahmen die Fluide ihre kennzeichnende Lösungsfracht auf. Danach fließen sie einem Druckgefälle folgend aus dem Bildungsraum ab, z.T. unter weiteren Reaktionen mit Nebengesteinen. Chemische oder physikalische Zustandsänderungen im Verlauf der Fließwege induzieren den Mineralabsatz. Retrograde Laugung hingegen findet statt, wenn ein noch heier metamorpher Komplex nach Durchlaufen der maximalen p/T-Bedingungen durch von außen zufließende Wässer geflutet und abgekühlt wird; dies wird gewöhnlich mit Aufstieg und Dehnungstektonik verbunden sein, weshalb die resultierenden Konvektionszellen zur Oberfläche offen sind. Metamorphogene Lagerstätten können nicht nur mit Feldmethoden als solche erkannt werden, da sie dort einfach als epigenetische hydrothermale Mineralisationen erscheinen. Nur die Anwendung eines breiten Spektrums geeigneter Labormethoden erlaubt eine richtige Zuordnung. Es wird erwartet, daß zukünftige Forschung dadurch wesentliche Fortschritte erzielt, daß die Entwicklung metamorpher Komplexe in Zeit und Raum quantitativ untersucht wird, ähnlich wie jene sedimentärer Becken in der modernen Erdölgeologie.


This paper was presented at the IGCP 291 Project Symposium Metamorphic Fluids and Mineral Deposits, ETH Zürich, March 21–23, 1991.  相似文献   

9.
Over the past two decades, whenever a copy of Journal of Geological Society of lndia has reached my hand, the first thing I have done is read the editorial. No matter what their topics are, these essays are never dull but lively and precise presentations of various earth science issues facing the developing countries and oftentimes the world as well.Coming from the pen of Dr. B. P. Radhakrishna,  相似文献   

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 Sinkhole development along the western shore of the Dead Sea became a major concern in 1990 with the appearance of a series of holes 2–15 m diameter and up to 7 m deep in the Newe Zohar area. One of these sinkholes, below the asphalt surface of the main road along the western shore of the Dead Sea, was opened by a passing bus. Repeated infilling and collapse of these holes indicated the extent of this ongoing process and the significance of this developing hazard. Since then sinkholes have developed in other areas including Qalia, Ein Samar, Ein Gedi and Mineral Beach. Three main types of sinkholes have been recognized. Gravel holes occurring in alluvial fans, mud holes occurring in the intervening bays of clay deposits between fans and a combination of both types at the front of young alluvial fans where they overlap mud flats. Fossil, relict sinkholes have been observed in the channels of some old alluvial fans. Sinkhole development is directly related to the regression of the Dead Sea and the corresponding lowering of the regional water table. Continuation of this process widens the neritic zone enveloping the sea and increases the sinkhole hazard of the region. Received: 4 February 1999 · Accepted: 8 April 1999  相似文献   

12.
In a joint enterprise, mostly Eastern Sahara artesian waters have been investigated. Age determinations and geochemistry allow geological conclusions. The rains responsible for the waters probably fell in a Pluvial about 25–35000 years ago. Their infiltration took place (simultaneously with or shortly after the lowest Würm-level of the Mediterranean) mainly in Nubian sandstone regions and within Oasis-depressions of Western Egypt. The upper levels of the geological reservoir seem to have been leaked out during the eustatic lowering of the Mediterranean level via an overdeepened Nile-bed. Infiltration trapped air within the pore-space of Nubian sandstone. This air re-appears to-day — after having lost its Oxygene etc.-content — as Nitrogene-gas.Münnich andVogel describe (?Untersuchungen an pluvialen Wässern etc.“) detailed investigations concerning the absolute age of these (and generally such) waters. E. T.Degens, in his part ?Geochemische Untersuchungen etc.“, deals with the geochemistry of the occurrences, mainly with some stable isotopes.  相似文献   

13.
Two occurrences of Viséan ammonoids in the Ural Mountains form the basis for this paper. In the Kzyl-Shin Gorge on the Kiya river, Aktiubinsk province, a bed of gray fragmental limestone, 1 m thick, has yielded the following genera: *Prolecanites, *Pronorites, Beyrichoceras, *Nomismoceras, *Girtyoceras, Trizonoceras, Arcanoceras, and *Goniatites. Also, east of the village of Novosamarskaya on the Sakmara river, Orenburg province, a black limestone block contains the genera marked with an asterisk (*) in the list above, together with Kazalchoceras. The Kzyl-Shin assemblage is of particular interest because it includes Beyrichoceras, generally not found with Goniatites this high in the Carboniferous section. Based on the Goniatites, assignable to the group of G. crenistria Phillips, and other components, the assemblage is dated as very late Visean. It probably is equivalent to the bottom part of the Caney Shale of Oklahoma that contains Girtyoceras meslerianum (Girty) and Goniatitesmultiliratus Gordon. The overlying part of the Caney Shale and the higher beds near the Kzyl-Shin Gorge contain Neoglyphioceras and are considered to be Namurian in age. New species described in this paper are Prolecanites kiaensis, Pronorites ultimus, Beyrichoceras tardum, Girtyoceras kazakhorum, and Arcanoceras praecox. --M. Gordon, Jr.  相似文献   

14.
This article looks at how five environmental leaders in Jogjakarta became environmentally active, and at the groups and interventions they formed. Interview data are drawn from a broader project that aimed to find out what might turn an Indonesian person into someone who cares for the environment. It examines the journey in leadership as “becoming” in the terms of Deleuze and Guattari (1987); a journey constituted in the desire to make something different. Against a backdrop of day-today practices in Central Java that do not favour environmental conservation and sustainability, the five informants seized upon an idea, a praxis, and explored it in the company of like-minded others, to join or make an organisation or action dedicated to redressing environmental crisis or neglect.  相似文献   

15.
This paper examines the use of an interaction coefficient to couple sedimentation and consolidation phenomena with the conventional finite strain consolidation theory. A specific continuous interaction function was implemented and the resulted model was examined. The model was found to able to capture proper sedimentation–consolidation features. It was also determined that the structural and maximum suspension void ratios are the major factors controlling the shape of the void ratio profile. The model was compared with experimental data and other numerical models and qualitatively good agreement was obtained.  相似文献   

16.
Incorporation of the Kaapvaal craton within a speculative Neoarchaean–Palaeoproterozoic supercontinent has long been debated, and this idea provides a potential solution to solving the apparently enigmatic provenance of the huge quantities of gold within the famous Witwatersrand auriferous deposits of Kaapvaal. Within a framework of a postulated Neoarchaean “Kenorland” (“northern”; present-day reference) supercontinent, we examine possible “southern” cratons that may have been contiguous with Kaapvaal: Pilbara, Zimbabwe, Dharwar, São Francisco, Amazon, Congo. Brief reviews of their basic geology and inferred evolution in syn-Witwatersrand basin times (c. 3.1–2.8 Ga) show no obvious support for any such supercontinental amalgamations. An alternative idea to explain a measure of gross similarity amongst several Neoarchaean cratons is through global events, such as a c. 3125–3000 Ma cratonic-scale erosive event interpreted for both Pilbara and Kaapvaal, and a much more widespread magmatic event at c. 2760–2680 Ma. We postulate that a global superplume event at c. 3.0 Ga included a plume beneath the Kaapvaal cratonic nucleus, thus halting any subduction around that terrane due to the thermal anomaly. Such a speculative global magmatic event is assumed to have enhanced production of juvenile oceanic crust at mid-ocean ridges, including those “offshore” of the thermally elevated Kaapvaal nucleus. Intra-oceanic obduction complexes may have built up fairly rapidly under such conditions, globally, and once the plume event had abated, “normal” plate tectonics would have resulted in composite (greenstone-tonalite, possibly also including granite) terranes accreting with nuclei such as Kaapvaal. This enhanced plume-related cratonic growth can be seen as a rapid accretion event. Formation of the envisaged ophiolite complexes possibly encompassed deformation-related first-order concentration of gold, and once accretion occurred around Kaapvaal's nucleus, from north and west (present-day frame of reference), a second-order (deformation-related) gold concentration may have resulted. The third order of gold concentration would logically have occurred once placer systems reworked detritus derived from the orogens along the N and W margins of Kaapvaal. Such conditions and placer gold deposits are known from many Neoarchaean cratons. The initial source of gold was presumably from the much hotter Mesoarchaean mantle and may have been related to major changes in Earth's tectonic regime at c. 3.0 Ga. The unique nature of Kaapvaal is probably its early stabilization, enabling formation of a complex flexural foreland basin system, in which vast quantities of placer sediments and heavy minerals could be deposited, and preserved from younger denudation through a unique post-Witwatersrand history.  相似文献   

17.
Zusammenfassung Den Grundlagen der C-14-Datierung von Wasser folgen Ausführungen über Ursprung und Anfangskonzentration dieses Isotops im Grundwasser, Verfälschungsmöglichkeiten und Ausführungen über das Isotopenverhältnis C-13/C-12 als geologisches Instrument. Der Hauptteil der Arbeit beschäftigt sich mit der Altersberechnung der in Frage stehenden Grundwasserproben.
Basal considerations concerning C-14-dating include origin and primary concentration of this isotope in subsurface waters. These and, C-13/C-12 proportion are discussed in their value for geological conclusions. Finally, absolute-age determinations of this kind are dealt with.

Résumé Sur la base de la datation des eaux à partir du C 14, les auteurs présentent leurs déductions sur l'origine et la concentration de cet isotope dans les eaux des nappes aquifères ainsi que sur les contaminations possibles, et s'étendent sur le rapport des isotopes C-13/C-12 comme instrument géologique.La partie principale du travail a trait aux calculs d'âge des eaux prélevées ici.

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River related tourism in Europe — an overview   总被引:1,自引:0,他引:1  
Josef Steinbach 《GeoJournal》1995,35(4):443-458
This paper gives an overview of different types of river-oriented tourism in Europa. All of them belong to the growing sectors of the business. They are based on essential characteristics of river landscapes as common factors of attractiveness. A series of supply-oriented indicators is used to draw up a ranking of the European river-cruise-districts. The cruising market is characterized by extensive investment strategies of some leading companies. In order to attract also younger people and families, they have to develop new structures of supply. The canal-systems of Western Europe form the most important prerequisite for houseboat-tourism. It's main districts can be ranked by the indicator: number of the types of charterable boats. The rising request for adventures and progress in kayak- and raft-technology are driving factors to whitewater-tourism. It's more important districts in the Alps, Pyrenees as well as in different medium mountains are shown. The shift into higher mountain regions causes ecological problems and severe personal risks. Biking has become a prefered leisure activity with river basins as the main goal areas. Some essential characteristics are given by the examples of two most significant routes: the Austrian Danubetrail and the Bavarian Altmühl-route. Finally, the planning concept of integral management of river basins is discussed which should support and coordinate the different styles of river-oriented tourism.  相似文献   

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