Stratabound lead-zinc pyrite ore deposits in upper precambrian carbonate rocks, Rodna Mountains, Romania

1983 ◽  
Vol 18 (3) ◽  
pp. 519-528 ◽  
Author(s):  
G. Udubaşa ◽  
L. Nedelcu ◽  
A. AndĂr ◽  
P. AndĂr
Keyword(s):  
Carbonate Rocks ◽  
Ore Deposits ◽  
Lead Zinc

Cathodoluminescence Microscopy: A Valuable Technique for Studying Ceramic Materials

MRS Bulletin ◽  
1989 ◽  
Vol 14 (11) ◽  
pp. 54-59 ◽  
Author(s):  
Richard D. Hagni ◽  
Musa Karakus
Keyword(s):  
Carbonate Rocks ◽  
Standard Technique ◽  
Ceramic Materials ◽  
Ore Deposits ◽  
Luminescence Microscopy ◽  
Geological Materials ◽  
The Past ◽  
Argillic Alteration ◽  
Lead Zinc ◽  
Growth Zoning

Over the past 10 to 20 years, cathodo-luminescence microscopy (CLM) has become an important, standard technique for studying many geological materials, but its application to ceramic material has not been fully realized. CLM has been found to be especially valuable in determining original porosity in carbonate rocks, a feature that was extremely important in determining the ability of petroleum and related fluids to migrate through the rocks and concentrate in the favorable structures where petroleum is found today. CLM constitutes one of the most significant techniques employed in the exploration for petroleum, but the results of those investigations remain largely unpublished in company files. A number of investigations have discussed the application of cathodoluminescence (CL) to studies of porosity in carbonates.Other applications of CLM to geology involve metals exploration. Halos of red CL feldspar in the rocks around carbon-atite deposits, which may contain rare earths, copper, and other metals, contrast with feldspar crystals with blue or blue-green CL that are distal from the ore deposits. Dolomite associated with lead-zinc ores may exhibit growth zoning by CL that can be used to trace the path of the ore fluids for distances of 100 miles or more. The detection of host rock limestone alteration in the Tri-State zinc-lead district, potassic and argillic alteration at the Henderson molybdenite mine, and ore guides in other metallic deposits by CL was discussed by Hagni.

Estimation of copper ore deposit parameters – case study of Rudna Mine mining block R-1 (SW part of Poland) using geostatistics

2021 ◽  
Author(s):  
Barbara Namysłowska-Wilczyńska
Keyword(s):  
Carbonate Rocks ◽  
Mineral Resources ◽  
Ore Deposits ◽  
Upper Permian ◽  
Spatial Analyses ◽  
Copper Ore ◽  
Cu Content ◽  
Copper Mineralization ◽  
Rock Formations ◽  
Mineralized Zone

<p>This geostatistical study investigates the variation in the basic geological parameters of the lithologically varied deposit in mining block R-1 in the west (W) part of the Rudna Mine (the region Lubin – Sieroszowice, SW part of Poland).</p><p>Data obtained from the sampling (sample size N = 708) of excavations in block R-1 were the input for the spatial analyses. The data are the results of chemical analyses of the Cu content in the (recoverable) deposit series, carried out on channel samples and drilled core samples, taken systematically at every 15-20 m in the headings.</p><p>The deposit profile comprises various rock formations, such as: mineralized Weissliegend sandstones, intensively mineralized upper Permian dolomitic-loamy and loamy copper-bearing schists and carbonate rocks: loamy dolomite, striped dolomite and limy dolomite, of various thickness. No schists formed in some parts of block R-1, which are referred to as the schistless area. The deposit series here is considerably less mineralized (comparing with other mining blocks) even though the mineralization thickness of the sandstone and carbonate rocks reaches as much as 20 m.</p><p>The variation in the Cu content and thickness of the recoverable deposit and the estimated averages Z* of the above parameters were modelled using the variogram function and the ordinary (block) kriging technique. The efficiency of the estimations was characterized.</p><p>As part of the further spatial analyses the Z<sub>s</sub> values of the analysed deposit parameters were simulated using the conditional turning bands simulation. Confidence intervals for the values of averages based on the estimated averages Z* and averages <strong> </strong>based on the simulated values (realizations) Z<sub>s</sub>, showing the uncertainty of the estimations and simulations, were calculated.</p><p>The results of the analyses clearly indicate the shifting of the mineralized zone (the mineralizing solutions), sometimes into the sandstones while spreading throughout the floor of calcareous-dolomitic formations and sometimes into the carbonate rocks, partly entering the roof layers of sandstones. It can be concluded that the process of deposit formation and copper mineralization variation had a multiphase character and the lateral and vertical relocation of the valuable metal ores could play a significant role.</p><p>The combination of various geostatistical techniques - estimation and simulation - will allow for more effective management of natural resources of mineral resources, including copper ore deposits.</p>

Pétrographie et altération de la matière organiquedu gisement de plomb–zinc–cuivre de tourist–Bou Beker,Maroc nord oriental

1996 ◽  
Vol 33 (10) ◽  
pp. 1363-1374 ◽  
Author(s):  
M. Bouadellah ◽  
A. C. Brown ◽  
Y. Héroux
Keyword(s):  
Organic Matter ◽  
Ore Deposits ◽  
Mississippi Valley ◽  
Sulfide Mineralization ◽  
Mineralization Process ◽  
Associated Gas ◽  
Regional Flow ◽  
Lead Zinc ◽  
Reflectance Measurements ◽  
Ore Deposition

Reflectance measurements and organic petrography were used to study altered organic matter in the dolomitic Middle Jurassic Beddiane sequence hosting the Beddiane lead–zinc deposit. Organic matter occurs in the lower dolostone units of the formation where zinc sulfide mineralization prevails. The upper units, where lead sulfide mineralization is dominant, contain lesser amounts of organic matter. The organic matter in the Beddiane sequence consists of macerals, amorphous kerogen, and solid bitumen, inertinite and vitrinite are ubiquitous. The amount of exinite increases toward mineralized areas but the ratio exinite/kerogen remains constant. Two types of vitrinite are considered on the basis of their reflectance: Vt1 with low reflectance values (0.3–0.5%) and Vt2 with higher values (0.7–1.25%). The ratio Vt1/Vt2 increases and the reflectance values for Vt1 decrease toward the zinc-prevailing units, Organic matter associated with the mineralization exhibits features such as oxidation halos and desiccation cracks, together with a low-fluorescent exinite. The association of the kerogen content, the trend in reflectance values, and the alteration features of the Mississippi Valley-type Beddiane deposit support the hypothesis that the regional flow of hot brines associated with the mineralization process was the cause of anomalous heating, that the occurrence of exinite maceral and its associated gas played a role in the ore deposition, and that the new chemical equilibrium reached by the zinc-dominant host rock after ore deposition is responsible for the suppressed reflectance values within and near the ore deposits.

Geochemical significance and Formation of Suçatı Pb-Zn Deposits – Eastern Taurides

2020 ◽  
Author(s):  
Ali Erdem Bakkalbasi ◽  
Hatice Nur Bayram ◽  
Mustafa Kumral ◽  
Ali Tugcan Unluer
Keyword(s):  
Carbonate Rocks ◽  
Field Studies ◽  
Hydrothermal Activity ◽  
Ore Deposits ◽  
Central Anatolia ◽  
Lower Permian ◽  
Ore Minerals ◽  
Geochemical Significance ◽  
Mvt Deposits ◽  
Marine Platform

<p><strong>Geochemical significance and Formation of  Suçatı Pb-Zn Deposits – Eastern Taurides</strong></p><p>Hatice Nur Bayram<sup>(1)*</sup>, Ali Erdem Bakkalbaşı <sup>(1)*</sup>, Mustafa Kumral<sup>(1)</sup>, Ali Tuğcan Ünlüer<sup>(1)</sup></p><p><sup>(1)</sup>Istanbul Technical University, Department of Geological Engineering, Istanbul/Turkey</p><p>(*E-mail: [email protected])</p><p> </p><p>The Middle Tauride Orogenic Belt is a productive enviroment in terms of Pb-Zn ore deposits, mostly associated with Permian aged dolomitized, shallow marine platform type carbonate rocks. There have been many studies on the origin of the ore deposits in the region, there are two important approaches that stand out for the formation of the ore deposits: the first theory is hydrothermal deposits with magmatic origin, and the other theory is Missisippi Valley-type (MVT) deposits related with the carbonate rocks commonly found in the region. Field studies at the Suçatı (Kayseri – Yahyalı, Central Anatolia, Turkey, East of Aladağlar extension of the Taurides) ore district in the Aladağ geologic unit indicate that the deposits in the region are associated with Paleo-Tethys limestones, fossiliferous limestones and dolomitic limestones. Mineralization is related to Lower Permian aged carbonate rocks include primary mineralization ore minerals as galena, sphalerite, smithsonite and goethite and as a product of hydrothermal activity, calcite mineral filled within fractures and cracks represents gangue minerals. As a result of geochemical analysis of the samples collected from the ore zones, PbO values range between 25.93% - 0.012%, ZnO values range between 51.01% - 0.042%, Fe<sub>2</sub>O<sub>3</sub> values range between 42.81% - 10.21%. In conclusion hydrothermal activities closely related with compressional and extentional tectonic regimes took place in multiphase mineralization.</p><p> </p><p><strong>Keywords:</strong> Pb-Zn Deposits, MVT, Taurides, Yahyalı</p>

Symposium: Role of organisms and organic matter in ore deposition/Le rôle des organismes et de la matière organique dans la formation des gisements métallifères

1985 ◽  
Vol 22 (12) ◽  
pp. 1890-1892 ◽  
Author(s):  
R. W. Macqueen
Keyword(s):  
Organic Matter ◽  
Ore Deposits ◽  
Sulphate Reduction ◽  
Sulphide Mineral ◽  
Special Session ◽  
Geochemical Cycle ◽  
Lead Zinc ◽  
Pine Point ◽  
Earth’S System ◽  
Ore Deposition

The following seven papers were presented on May 16, 1984, at the Geological Association of Canada and Mineralogical Association of Canada joint annual meeting. The special session, organized by R. W. Macqueen and J. A. Coope, contained 10 papers and was sponsored by the Mineral Deposits Division of the Geological Association of Canada.Our objective in organizing the special session was to examine organically based processes and relationships that may be of major importance to the origin of ore deposits. As noted by Fyfe (1984), the concept of the geochemical cycle focuses attention on pathways of chemical elements and isotopes of the Earth's system during geologic history. It is clear from the chemistry of carbon-rich materials that a wide range of elements is concentrated directly or indirectly by biological processes operating as part of the geochemical cycle. Two of the papers of the special session examine some of these concentration processes, although definitive links to actual ore deposits cannot be made yet. Beveridge and Fyfe document the remarkable ability of the anionic cell walls of certain bacteria to concentrate metals and to provide sites for nucleation and growth of minerals. In a related paper, Mann and Fyfe show that several species of simple freshwater green algae readily concentrate large amounts of uranium under both experimental and natural conditions (Elliot Lake and Thames River, Ontario).Two papers deal with aspects of sulphate reduction. Birnbaum and Wireman describe controlled experiments that suggest that sulphate-reducing bacteria may be involved in the selective replacement of sulphate-evaporite minerals by silica and in the precipitation of silica in association with sulphide mineral phases in banded iron formations. Their work focuses directly on the effect that bacterial sulphate reduction has on silica solubility. Trudinger et al. examine the question of mechanisms of sulphate reduction at temperatures less than 200 °C and the bearing this has on origin of sulphide for low-temperature sulphide ore deposits. Although there is empirical evidence favouring abiological sulphate reduction at temperatures in the vicinity of 100 °C, Trudinger et al. have not been able to demonstrate abiological reduction of sulphate under controlled laboratory conditions and at temperatures under about 200 °C. Perhaps catalysts, as yet undiscovered, are involved in this process in nature.Impressive progress has been made in understanding the diagenetic evolution of organic matter in response to heat and pressure in geological environments: excellent reviews are found in Barnes et al. (1984) and Bustin et al. (1985). Simoneit's paper examines and reviews the genesis of petroleum in a most unusual setting, that of the active ocean ridge spreading centre of Guaymas Basin, Gulf of California. There, in the vicinity of black smokers and associated metallic sulphide deposits, petroleum originates instantaneously geologically as a result of hydrothermal activity. The question of genetic involvement of organic matter in the origin of the metallic sulphides (e.g., reduction of sulphate to H2S) cannot be answered yet for this setting with the available data.The final two special session papers included here are concerned with organic matter associated with mineralization in Canadian Shield Precambrian settings. Willingham et al. demonstrate that Elliot Lake – Blind River Early Proterozoic uranium deposits with minor amounts of associated gold also contain kerogen-like organic matter. Some of this organic matter has anomalously rich amounts of gold and uranium and appears to have originated as mats of cyanobacteria, possibly with the ability to concentrate these metals. For a number of settings in the Archean-aged Abitibi greenstone belt of Ontario and Quebec, Springer demonstrates that carbon, at least partly of organic origin, is closely associated with some gold deposits. Her interpretation is that carbon activated by shear-zone-associated hydrothermal fluids has provided sites for fixing some of the gold.Three of the papers given at the special session are not included here. H. T. Shacklette reviewed metal uptake by young conifer trees, demonstrating that nursery-grown seedlings of several species readily concentrated a variety of metals, including lead, zinc, tin, and gold, over a 7 year period. This work is of interest to those involved in geochemical prospecting and is now published elsewhere (King et al. 1984). R. W. Macqueen presented quantitative data on the genesis of sulphide by abiological bitumen–sulphate reactions at the Pine Point lead–zinc property, Northwest Territories, Canada (Macqueen and Powell 1983; Powell and Macqueen 1984). Although Trudinger et al. have not been able to demonstrate abiological reduction of sulphate at temperatures approximating those of Pine Point [Formula: see text], the data presented by Macqueen (Powell and Macqueen 1984) are consistent with the amounts, alteration, and composition of bitumens at Pine Point, as well as with the presence of native sulphur and the sulphur isotope compositions of the various Pine Point sulphur species. This work is continuing, and a more extensive account is in preparation. J. R. Watterson examined relationships between freezing climates and the local chemical behaviour of gold in the weathering cycle, concluding that ice-induced accumulation of organic acids, bacteria, and other organic matter at mineral surfaces may increase rates of chemical attack, leading to dissolution of normally insoluble metals such as gold (Watterson 1986).Interest in organic aspects of the geochemical cycle, including ore deposition, is growing dramatically (e.g., Fyfe 1984). Although the following papers address a limited range of topics within the field, they do indicate some of the diversity and variety of active processes and associations between metallic elements and organic components. Perhaps, in the not too distant future, we will be able to identify or even discover whole classes of ore deposits that owe their origin directly to organic influences operating within the geochemical cycle.

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