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41.
Dr. H. Kucha 《International Journal of Earth Sciences》1990,79(2):387-399
Cu, Pb and Zn are the main metals occurring in sulfides in the Kupferschiefer. They are arranged in the three distinct zones around »Rote Fäule«, in the order Cu, Pb and Zn. Copper zones are enriched in transition metals, i.e. Ag, Ni, Co, V and Mo ranging from 600 to 1500 ppm; they are concentrated especially in the bottom part of black shale. Re is associated with Mo; the Re: Mo ratio in Cu-, Pb- and K-castaingites is about 170.In copper zones, near the contact with lead zones, Au, platinum group metals (PGM) and U are concentrated, ranging from traces to several hundred ppm. The main mechanism of concentration of transition metals was catalytic autooxidation and dehydrogenation of organic matter.The noble metals form either independent minerals or are present in organic matter and thucholite. In the lead zones, at the contact with Cu zones, an increased content of Ag (100–1500) and Hg (5–800) ppm is present. The average Hg content for the black shale of the zone is 61 ppm.A natural gas, exploited from the Rotliegendes beneath the Kupferschiefer, carries, in aerosols, significant amount of Pb, Cu, Mn, Fe, Ag and Hg. This suggests the Rotliegendes as a pathway or as a source of metals for the Kupferschiefer. The presence of K-castaingite intergrown with silvinite (KCl) may suggest K-dominated brines as the mineralizing fluids.
Zusammenfassung Die häufigsten Metalle, die in den Sulfiden des Kupferschiefers vorkommen, sind Kupfer, Blei und Zink. Diese Metalle sind in der Reihenfolge Cu-Pb-Zn an drei bestimmte Zonen um die »Rote Fäule« gebunden.Die Kupfer-führenden Zonen sind reich an Übergangsmetallen wie Ag, Ni, Co, V und Mo, deren Konzentrationen zwischen 600 und 1500 ppm schwanken und die hauptsächlich in bodennahen Bereichen des Schwarzschiefers angereichert sind. Dabei tritt Re in Verbindung mit Mo auf und das Re-Mo Verhältnis in Cu-, Pb- und K-Castaingiten ist ungefähr 170.Gold, Platin-Gruppen-Metalle (PGM) und Uran, deren Konzentrationen zwischen geringen Spuren und mehreren 100 ppm liegen, findet man in Kupfer-führenden Schichten in der Nähe von Kontakten zu Blei-führenden Zonen. Katalytische Autooxidation und Dehydrogenisierung organischen Materials sind die dominierenden Mechanismen, die die Anreicherung der Übergangsmetalle steuern. Die Metalle liegen als Minerale oder gebunden an organische Substanz und Thucholit vor.In den Kontaktbereichen der Blei- und Kupferzonen findet man erhöhte Werte von Ag (100–1500 ppm) und Hg (5–800 ppm). Der Durchschnittswert für Hg im Schwarzschiefer beträgt 61 ppm.Ein natürliches Gas, das aus dem den Kupferschiefer unterlagernden Rotliegenden gefördert wird, enthält als Aerosole bedeutende Mengen an Pb, Cu, Mn, Fe, Ag und Hg. Somit ist es wahrscheinlich, daß das Rotliegende entweder als Quelle der Metalle des Kupferschiefers oder zumindest als Durchgangsstation der Metallführenden Lösungen anzusehen ist. Das Vorkommen von K-Castaingit-Verwachsungen mit Silvinit (KCI) spricht für K-reiche Solen als mineralisierende Lösungen.
Résumé Le Cu, le Pb et le Zn sont les métaux principaux des sulfures de la formation des Kupferschiefer. Ils sont distribués autour de la «Rote Fäule» en trois zones distinctes, dans l'ordre: Cu - Pb - Zn.Les zones à Cu sont enrichies en métaux de transition (Ni, Co, V et Mo) quiy présentent des teneurs de 600 à 1500 ppm; ces métaux sont concentrés spécialement dans les parties inférieures des schistes noirs. Le Re est associé au Mo, avec un rapport Re/Mo de l'ordre de 1,70 dans les castaingites à Cu, Pb et K.Dans les zones à Cu, près du contact avec les zones à Pb, on observe une concentration de Au, de U et des métaux du groupe du Pt, avec des teneurs qui vont des traces à quelques centaines de ppm. Le mécanisme principal de la concentration des métaux de transition a été l'auto-oxydation et la déshydrogénation catalytiques de la matière organique. Les métaux nobles sont sous la forme de minéraux indépendants, ou sont contenus dans la matière organique et la tucholite.Dans les zones à Pb, il existe une concentration en Ag (100–1500 ppm) et en Hg (5–800 ppm) au contact avec les zones à Cu. La teneur moyenne en Hg des schistes noirs est de 61 ppm.Un gaz naturel, exploité à partir des Rotliegende situés sous les Kupferschiefer, renferme, sous forme d'aérosols, des quantités appréciables de Pb, Cu, Mn, Fe, Ag et Hg. Les Rotliegende pourraient donc être soit la source, soit le chenal des métaux contenus dans les Kupferschiefer. La présence d'intercroissances de castaingite potassique et de sylvinite (KC1) suggère que les fluides minéralisants ont pu être des solutions potassiques.
, . «Rote Fäule»., , , .: Ag, Ni, Co, V , 600 1500 ppm; . Re , Re/Mo , 170., , , , , . . , . (100–1500 ppm) Hg (5–800 ppm). 61 m. , , , , , . , , , , - , « » , . KCl , .相似文献
42.
Poland largely encompases the estuary of the Vistula and Odra rivers, which drain into the Baltic Sea. Only a very small area of the south-east part of the country is within the Black Sea Basin. Poland contributes significantly to the pollution of the Baltic Sea, with biogenic nutrients and organic substances. Poland includes more than half the coastal inhabitants of the Baltic Sea, and they use 40% of the arable land situated there. The contribution to the pollution of this sea with nitrogen, phosphorus and organic substances is approximately 30, 40 and 22%, respectively. The main sources of nutrients are untreated sewage and the runoff and leakage of fertilizers from agricultural land. The natural conditions in Poland are poorer than in Western Europe due to the prevalence of light soils and a short growing period with frequent droughts. After correcting the synthetic index for soil and climate, it was estimated that for each inhabitant of Poland there are 0.3 ha of farmland, which is comparable to that of Western Europe. For the maintenance of the population, intensive agricultural production must be accompanied by environmental protection regulations. Polish agriculture is not only a polluter but also a recipient of pollution, especially the deposits of sulphur and heavy metals emitted by industry and municipal areas. The estimated annual emission of sulphur dioxide is about 4 million t, which equals an average deposit of about 90 kg of sulphur per hectare of farmland. The pedological processes and acid deposits cause more than 60% of agricultural land in Poland to be acidic. The contamination of soils with heavy metals in general is lower than in Western Europe, but in some areas (e.g. Upper Silesia) it exceeds the safe limits. 相似文献
43.
Additional absorption features in the red wings of the resonance Mgii lines near 2800 Å are found in the observations of Algol made by Chen and Wood (1976) from theCopernicus satellite. The absorption features were clearly seen only during a part of the primary eclipse, in the phase interval 0.90–0.03.The observations are interpreted as produced by a stream of matter flowing from Algol B in the direction of Algol A. The measured Doppler shifts of the features give the value of 150 km s–1 as the characteristic velocity of matter in the stream. The mass transfer connected with the stream is estimated to be of the order of 10–13
M
yr–1. 相似文献
44.
Polished ore samples from the world-class Bleiberg lead-zinc deposit in Austria were studied by Field Emission Scanning Electron Microscopy (FESEM) at magnifications in the range of 105–106. The zinc ore shows nano-sized sphalerite filaments and spherules which are morphologically similar to recent biofilms of sulphate-reducing bacteria. The activity of sulphate-reducing bacteria is suggested by a large 34S difference of ~40 between coeval seawater sulphate (+16 ) and sulphide sulphur (< –25 ) in the Bleiberg ores, and by variable sulphur valences. Peloids of sphalerite, Zn-bearing calcite and pyrite have features typical of bacterial colonies. Combined with geological and mineralogical evidence, a significant role of bacteria during ore deposition at Bleiberg is likely.Eugen F. Stumpfl deceasedEditorial handling: B. Lehmann 相似文献
45.
Sulphide and carbonate minerals from nine bituminous coal seams of a Paralic Series were investigated by means of polished-section microscopy, scanning electron microscopy and absorption spectral analyses. In addition to syngenetic accumulations of kaolinite, illite and quartz, diagenetic veinlets of subhedral pyrite and marcasite most often occur in vitrinite clast fissures and in post-tectonic fissures, nests and lenses with fusinite. Epigenetic anhedral and subhedral grains of ankerite, dolomite, siderite and calcite are also frequently found in post-tectonic veins. Pyrite replaced some of the marcasite grains and it dominates in older coal seams in the Flora Beds as compared with the Grodziec Beds. Occasionally there are anhedral and subhedral galena, sphalerite and chalcopyrite grains among coal macerals as well as cerussite among post-tectonic carbonate veins. They all represent the only minerals that are abundant in definite chalcophile elements (Cd, Co, Cu, Ni, Pb, Zn). In addition to the minerals just mentioned, the elements occurred in pyrite and ankerite grains, which contained inclusions of fusinite and other minerals (among others, clay and carbonate minerals in pyrite, pyrite in carbonates). Although there is a low content of minerals accumulating Cd, Co, Cu, Ni, Pb and Zn, the minerals significantly influence the average concentration of elements in the coal seams. In the Grodziec Beds, mineral matter, especially carbonates and sulphides, determines (>50%) the concentration of Cd, Cu, Pb and Zn in coal. The basic part of Cd, Co and Ni in the coal seams of the Grodziec Beds and of Co, Cu, Ni, Pb and Zn in coal seams of the Flora Beds originates from organic matter. These regularities can be important, from an ecological perspective, in stating whether the coals investigated are useful for combustion and in chemical processing. 相似文献
46.
These Kupferschiefer deposits were probably formed as a result of a mixing of two brines. The upper cold brine (UCB) is an unmineralized brine rich in Na, Ca, Cl and SO4, with a pH>7 and originating from evaporites overlying the metal-bearing Zechstein rocks. The lower hot brine (LHB) rich in Mg, K, Cl, SO4 and CO3 with a pH<=7 formed in sediments in the central part of the Zechstein basin at a depth of 7,000 m. This brine was subjected to heating and upward convection toward the Fore-Sudetic monocline along the bottom of the Z1 carbonates. During its migration, it caused albitization, serpentinization and leaching of the primary metal deposits in rocks underlying the Zechstein becoming enriched in heavy metals. The mineralization process, being a result of the mixing of the two brines (UCB and LHB), and catalytic oxidation of the organic matter of the black shale were initiated at shallow depths in the area of the Fore-Sudetic monocline. The boundary of the two brines generally overlapped the strike of the black shale.Parts of the deposit with shale-free host rock suggest that the action of two brines alone was capable of producing economic concentrations of Cu, Pb and Zn. Where the boundary of the two brines overlaps the autooxidation zone (the black shale bottom) and also coincides with radiation of thucholite, concentrations of noble metals result.The characteristic vertical distribution of the triplet CuPbZn from the bottom upward is universal in the Kupferschiefer environment. 相似文献