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1.
Georadiochemical evidence to weathering of mining residues of the Mansfeld mining district,Germany 总被引：1，自引：0，他引：1
Mining heaps are used as archives for the investigation of weathering processes. Aim of this work was to investigate the different
weathering behavior of heap materials derived from Kupferschiefer mining with respect to environmental hazard. For this purpose,
Kupferschiefer and slag material of two heaps of different age were examined regarding to the radionuclide distribution and
geochemical composition. By measuring of the local dose rate, performing digital autoradiography and gamma spectrometry the
radiological load of the heaps and the heap materials was determined. The geochemical characterization of the samples was
performed by XRF, ICP–OES and ICP–MS. The results show a clear higher radionuclide load of the younger slag heap. A depletion
of chalcophile and lithophile elements in the older slag was determined. Apart from a homogeneous radionuclide distribution,
considerable radionuclide enrichments in fossil fragments could be proven. The results reveal a different weathering behavior
of slag material in comparison to the Kupferschiefer depending on the chemical binding of the elements on organic and inorganic
species. Natural organic matter as well as apatite in Kupferschiefer act as retention barrier for some metals. 相似文献
2.
The bulk composition of organic matter and saturated and aromatic hydrocarbons extracted from 16 samples collected from two Kuperschiefer profiles in the Rudna mine,Southwest Poland has been analyzed to study the role of organic matter during base metal enrichment in the Kupferschiefer shale.The results indicated that the extract yields and saturated hydrocarbon yields decreased with increasing base metal contents.GC and GC/MS analyses indicated that n -alkanes and alkylated aromatic compounds were depleted and may have served as hydrogen donators for thermochemical sulfate reduction.The enrichment of base metal is closely connected with the destruction of hydrocarbons. 相似文献
3.
孙玉壮 《中国地球化学学报》2004,23(2):101-111
Thirty-seven Kupferschiefer samples from southwestern Poland were analyzed by microscopy, Rock-Eval approach and instrumental neutron activation analysis to understand the geochemical and morphological characteristics of kerogen present in the samples. The analytical results indicate that there are two different types of kerogens. One type was only subjected to thermal alteration processes, and the other was further oxidized after deposition of the sediment.In the oxidized samples migrabitumen was transformed into pyrobitumen. Rock-Eval analyses show a significant decrease in HI values in the oxidized samples and an increase in OI values in relation to the samples that were not influenced by oxidation. Variations in S2 versus Corg contents indicate a change in kerogen from Type II to Type III with progressing oxidation. The presence of pyrobitumen and the depletion of hydrogen in the altered kerogen allow one to conclude that the kerogen was used as hydrogen donor for thermochemical sulfate reduction(TSR). 相似文献
4.
Immature samples of the Permian Kupferschiefer from the Lower Rhine Basin in N.W. Germany were analysed for tetrapyrrole pigment type and abundance. The sediment, thought to have been deposited in a marine regime with enhanced salinity, was found to contain high concentrations of metalloporphyrins. The porphyrins are complexed to nickel (Ni) and oxovanadium (V=0), but high abundances of iron (Fe) porphyrins were also detected using UV/visible spectroscopy and mass spectrometry. The presence in the latter of series of aetioporphyrins, cycloalkanoporphyrins, di-cycloalkanoporphyrins and benz-cycloalkanoporphyrins was confirmed by accurate mass measurements; HPLC co-injection of deoxophylloerythroetioporphyrin (C32 DPEP) with the demetallated iron porphyrins indicated its presence in the sediment as an iron complex. The study provides the first evidence for the occurrence of Fe porphyrins in geological samples other than coals and lignites, and reports the highest concentrations in sedimentary organic matter to date. 相似文献
5.
《Chemie der Erde / Geochemistry》2017,77(4):614-624
Water samples (springs, creeks, mine adits) from different former mining districts of the Harz Mountains and the nearby Kupferschiefer (copper shale) basin of Sangerhausen were analysed for major ions and trace metals. Due to more intensive water rock interactions including the ore minerals, the mine water concentrations of main components and trace metals are generally higher compared to non mining affected surface waters of the mountain range. Furthermore, the content of major ions in mine water is enriched by mixing processes with saline waters from Permian layers in the Kupferschiefer district and at the deeper levels of the mines in the Upper Harz Mountains. The waters of the different mining districts can be distinguished by trace metal occurrences and concentrations derived from the different ore bodies. Water from the Kupferschiefer mines shows the highest Na, Cl, Cu, Mo and U concentrations, whereas a combination of elevated As and Se concentrations is typical for most of the samples from the mines around St. Andreasberg. However, there are exceptions, and some water samples of all the investigated mining districts do not follow these general trends. Despite the influence of mining activities and ore mineralisation, hydrochemical effects due to rain water dilution can be seen in most of the waters. According to the elevation of the mountain range, higher precipitation rates decrease the ion concentrations in the waters of springs, creeks and mine adits. 相似文献
6.
A. Bechtel R. Gratzer W. Püttmann S. Oszczepalski 《International Journal of Earth Sciences》2000,89(1):72-89
max vs the present depth of the Kupferschiefer, soluble organic matter (SOM) yields, and relative proportions of saturated and
aromatic hydrocarbons of the SOM provide evidence for an oxidative alteration of organic matter in highly mineralized Kupferschiefer
samples near the Rote F?ule zones. This is confirmed by differences in the composition of the saturated and aromatic hydrocarbon
fractions of the soluble organic matter: Saturated hydrocarbons from Rote F?ule samples are dominated by short-chain n-alkanes
and higher abundances of pristane and phytane relative to heptadecane (n-C17) and octadecane (n-C18), respectively, compared
with samples more distant to the Rote F?ule zone. Compositional changes of the aromatic hydrocarbon fractions with decreasing
distance to that zone are characterized by the occurrence of polycyclic aromatic hydrocarbons and elevated ratios of phenanthrene
to methylphenanthrenes that are attributed to demethylation reactions and resulted in a decrease of the methylphenanthrene
index (MPI 1). Kupferschiefer samples from the barren zone of the Polish Basin do not show these alteration patterns. The
observed variations in organic matter composition with burial depth are consistent with changes due to increasing thermal
maturation. Maturity assessment is achieved from MPI 1 and the methyldibenzothiophene ratio (MDR). From the relationship between
the maturity of organic matter in terms of vitrinite reflectance values and depth of the Kupferschiefer strata, a continuous
increase in reflectance of vitrinite is obtained within the Polish Basin. The alteration pattern of organic matter related
to base metal mineralization of the Kupferschiefer corresponds to changes in the isotopic composition of organic carbon and
calcite. Kerogen within, or close to, Rote F?ule zone is enriched in 13C caused by the preferential release of isotopically light organic compounds through progressive degradation of organic matter.
The opposite tendency towards lower δ
13C and δ
18O values of calcite provides evidence for isotopic exchange between carbonate and the oxidizing, ore-bearing solutions and
for organic matter remineralization. In contrast, organic matter and calcite from the Kupferschiefer do not show regular trends
in δ
13C with increasing thermal maturation.
Received: 25 June 1999 / Accepted: 1 December 1999 相似文献
7.
Within the Central European Zechstein Basin the Permian Kupferschiefer has been deposited under anoxic conditions. In most parts of the basin, the metal content does not exceed values commonly observed in black shales. However, in areas near to the Zechstein sea-shore which are simultaneously related to rift zones a significant base metal enrichment is observed. Organic geochemical analyses of the copper-mineralized sections in the Kupferschiefer from Southwest Poland show that significant changes in the composition of organic matter are associated with the metal enrichment processes. Porphyrins, commonly abundant constituents of the shale, have been decomposed by oxidizing fluids. Additionally, aliphatic hydrocarbons have been largely removed from the bitumen and alkylated aromatic systems were affected by side-chain degradation. This particular type of alteration is explained by ascending oxidizing solutions which transported high amounts of base metals from Lower Permian red beds into the Kupferschiefer horizon acting as a geochemical trap. The metal precipitation is suggested to be a result of thermochemical sulphide production with organic matter acting as hydrogen source. In areas such as the Lower Rhine Basin in the bottom section of the Kupferschiefer the base metals lead and zinc as well as barium have been accumulated from basinal Carboniferous formation waters. Copper enrichment is not observed because potential source rocks are missing in this area. However, the observed compositional changes of the organic matter do not point towards thermochemical redox processes. 相似文献
8.
Geochemical Characteristics of a Veinlet Kupferschiefer Profile from the Lubin Mine, Southwestern Poland 总被引：3，自引：0，他引：3
Previous studies have shown that the ascending, oxidizing brines play a very important role in Kupferschiefer mineralization. Fractures could be the pathway of the brines. In order to clarify the influences of the brines on bulk organic matter, aromatic hydrocarbons and Kupferschiefer mineralization, one veinlet Kupferschiefer profile from the Lubin mine, southwestern Poland was studied with the microscopic, geochemical and Rock-Eval methods. The microscopic results indicate that organic matter of the veinlet sample consists dominantly of bitumen. Its extract content is higher than in other samples. The dominant aromatic compounds are naphthalene and alkylated naphthalenes (Na-PAH), which have migrated into the veinlet sample from other sediments. The content of phenanthrene and its methylated derivatives (Ph-PAH) is much lower than in other samples. The reason may be due to their heavier mass than Na-PAH. It is more difficult for Ph-PAH to migrate. The Na-PAH was probably removed from the shale by dist 相似文献
9.
SUN Yuzhuang Basin Reservoir Research Centre University of Petroleum Shuiku Ro Changping Beijing JIN Yujie China University of Mining Technology Beijing 《《地质学报》英文版》2000,74(1):93-101
Previous studies have shown that the oxidizing brines from the Early Permian Rotliegende sequence have influences on the organic matter of Kupferschiefer. However, inside the Rotliegende sequence there are two other black shales: the Lower and Upper Antracosia shales, which have not been studied as much in detail as in Kupferschiefer. In the present study 12 samples from the Lower and Upper Antracosia shales were analyzed by organic geochemical methods in order to clarify the influences of the oxidizing brines on organic matter. The results indicate that the organic matter of the samples from the Upper Antracosia shale and the bottom of the Lower Antracosia shale was oxidized under the influences of the oxidizing brines. The oxidation resulted in a depletion of saturated hydrocarbons and the alky Is of the aromatic compounds. 相似文献
10.
四川盆地西南缘二叠系页岩铜银矿床地质地球化学特征和流体对流成矿机制 总被引：1，自引：1，他引：0
四川盆地西南缘乐山—沐川地区的页岩铜银矿床产于上二叠统宣威组上部。地质和常量元素、稀土元素、热释光等地球化学证据表明, 页岩铜银矿床形成于成岩期,成矿流体和成矿物质主要来源于下伏的峨嵋山玄武岩。流体动力学分析表明成矿流体是以单环对流方式进行迁移,流体在玄武岩中迁移并淋滤Ｃｕ 、Ａｇ 金属形成含矿流体,沿西侧基底隆起上升,然后沿宣威组向盆地中心横向迁移,在盆地中部下渗返回玄武岩中形成一个长约１５ ｋｍ 、高约３００ ｍ 的近水平的对流环。进一步的分析与计算表明,该区具有良好的形成中型铜、大型银页岩矿床的地质、构造和流体动力学条件,但难以形成超大型的页岩铜银矿床。 相似文献