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EN
Stan Terg deposit, one of numerous occurrences within the Vardar Zone on the Balkan Peninsula, is located in the north-eastern part of Kosovo. The formation of the deposit was controlled by metasomatic processes between carbonates and volcanic intrusive rocks. Ore bodies are located on the contact between Tertiary volcanic breccias, and Triassic metamorphic Trepca Series (represented by schists and carbonates). Significant number of ore precipitated from hydrothermal fluids in paleokarst cavities. Galena, sphalerite, pyrite, pyrrhotite and arsenopyrite are the main components of the primary ore assemblage (Forgan 1950, Schumacher 1950, Palinkas et al. 2013). The weathering zone is not well developed in the deposit. Development of weathering zone was stopped by tuff series overlaying the area after volcanic activity. Gossan occurs, but it is seldom (Forgan 1950). However, the circulating water through the karstic system could have dissolved sulphides, as well as neighboring rocks, which led to the precipitation and formation of secondary minerals on the galleries walls inside the mine. The aim of the study is identification and description of secondary minerals paragenesis that is present on the corridor walls inside the mine. The knowledge about this kind of secondary minerals may led to determination of weathering conditions in the deposit. Secondary minerals described in this study occur in minor amounts and should be regarded rather as a curiosity and as a supplement of knowledge about Stan Terg deposit. Samples were collected at 6 level of the mine. 20 samples were investigated using of X-Ray Diffraction (XRD) and 5 samples by Raman spectroscopy. Secondary minerals occur mainly in form of fine-grained crystals, dripstones or incrustations. Among them copiapite, roemerite, epsomite, bianchite, melanterite, rozenite and gypsum have been recognized. Copiapite is present in form of yellow and yellowish fine-grained crystals. It is most common secondary mineral in the mine. It occurs together with roemerite and epsomite. Roemerite, macroscopically not visible, occurs in minor amounts. Epsomite occurs in form of fine-grained, fibrous aggregates, crusts or dripstones. It exhibits white color, but may be also orange, if mixed with copiapite. Small amounts of bianchite were found (using XRD) within fine-grained crusts of epsomite. Melanterite occurs as crusts and stalactites. It builds clear phases or occurs together with other, yet not recognized minerals. A further study of melanterite is needed for successful characterization this additional phases. Rozenite was confirmed only by XRD. This mineral occurs in greenish-white fine-grained aggregates. Gypsum is a widespread mineral in the deposit. It occurs as single phases (with fibrous, fine-grained, needle-like or tabular crystals habit) or in lesser amounts with all other secondary minerals. Weathering of primary ore minerals is related to underground water circulating through karst cavities and fractures within the Stan Terg deposit. Recognized secondary minerals are being an effect of metal sulfides oxidation when oxygen and water are present in the environment. Highly soluble sulphates are formed in such condition. Copiapite, rozenite, melanterite, roemerite, bianchite may be caused by quickly oxidization of pyrite to aqueous Fe2+ and SO42- . The source of zinc in bianchite is sphalerite, whereas the presence of the magnesium in epsomite may be linked to Mg-reach carbonates. All of described minerals precipitated from the solution.
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2015
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tom 6
42-52
EN
The main products of terrestrial weathering of metallic phases in Nantan meteorite are represented by: goethite, lepidocrocite and others nonstructural Fe-hydroxides with differ hydratation ratio. Sometimes iron hydroxides are associated with high-nickel phases. Hydrated iron phosphates are observed like, e.g. vivianite, in vicinity schreibersite. Only phosphides, relics of taenite and the hight-nickel phases are preserved in strongly weathered specimens. Generally, both the process of weathering and the types of secondary phases are similar in Nantan and Morasko meteorites. The differences are very small and are caused by slightly different chemical composition of both meteorites.
EN
Primary epithermal and secondary Cu mineralization in the Stary Lesieniec rhyodacite quarry, located within the Intra-Sudetic Depression, was studied using reflected light microscopy, powder X-ray diffraction, and electron microprobe. Samples containing copper sulphides, baryte, and secondary weathering minerals were collected from mineralized veinlets in the Upper Carboniferous rhyodacite. Copper sulphides (chalcocite Cu2S, djurleite Cu31S16, anilite Cu7S4 / digenite Cu9S5, and covellite CuS) are the major ore minerals and are associated with quartz, hematite, and very minor uraninite. The samples studied indicate phase transformation from chalcocite to anilite, which indicates that Cu sulphides began to crystallize at ~100°C. Then, during the epithermal stage of precipitation, the temperature of the solutions dropped <72°C, based on the Cu-S ternary diagram and anilite stability. Admixtures of Ag, Fe, Bi, and Se in the sulphides are very minor. Supergene paragenesis is represented by chrysocolla with minor brochantite and very scarce malachite. These only bear trace impurities at the anionic sites. The supergene oxidation process began with the formation of abundant chrysocolla, at a relatively neutral pH. After dropping of the pH to ~4-6, brochantite was deposited.
EN
Weathering processes of minerals which are presented in the Morasko meteorite are characterized by different speed of the secondary changes. The most resistant minerals for the alternations are phosphites (schreibersite, rhabdite, nickielphosphide) and carbides (cohenite) but also the mentioned phases show secondary fluctuation. Phosphites are changing into metallic, phosphorus free phases, which are similar to native nickel or avaurite (awaruitu) with very well visible modification of its crystal morphology. All phosphorus amount is introduced to secondary phosphates like vivianite. The carbides alternation processes occur in a different way than in case of phosphates. Carbon is free to the environment up to time, when the new phase is totally decomposed and replaced by hydroxyoxide of iron. Sometimes, the high-nickel metallic phases are also noted as the products of the weathering. All described mineral phases, that are resistant for secondary alternation might be indicators for high evolved meteoritic material in the Earth’s weathered rocks.
PL
Wietrzenie poszczególnych faz mineralnych, obecnych we fragmentach meteorytu Morasko, przebiega w różnym tempie. Za najbardziej odporne uznaje się fosforki (schreibersyt, rhabdyt, nickielphosphide) oraz węgliki (cohenit). Jednak po pewnym czasie również i te fazy ulegają rozpadowi. Z fosforków wyraźnie ubywa fosforu i przekształcają się one stopniowo w fazy metaliczne, zbliżone do taenitu lub awaruitu. Towarzyszy temu zmiana morfologii kryształów. Uwolniony fosfor wchodzi w skład wtórnych fosforanów typu wiwianit (vivianit). Węgliki zachowują się nieco odmiennie. Węgiel zostaje stopniowo uwalniany do środowiska a w dalszym etapie faza ta ulega całkowitemu rozpadowi przechodząc w wodorotlenki żelaza. Jednymi z ostatnich faz, które można dostrzec wśród wodorotlenków żelaza są wtórne fazy wysokoniklowe. Powyższe odporne na wietrzenie fazy, jako nieobecne na powierzchni Ziemi (z wyjątkiem krzemianów), mogą służyć identyfikacji meteorytowego pochodzenia silnie zwietrzałych skał.
5
Content available Wietrzenie meteorytu Muonionalusta
88%
EN
Muonionalusta meteorite is weathering over 0,8 Ma years in the subpolar climate. Fragments buried deep in the ground (up to about 2 meters) are usually well insulated so they are being found in virtually intact state. The main secondary phases are: Fe oxides (in different state of crystallization), with admixtures of Ni and Cl. Akaganeite is locally present. Moreover, in the final stage of weathering, there are observed awaruite and/or (native) nickel. Ge was not detected in the minerals, despite the fact that it was detected in the case in Morasko meteorites. Surface of the meteorite is not protected in surface conditions and corrodes. It is weathering very rapidly and it provides till total disintegration.
PL
Meteoryt Muonionalusta wietrzeje od ponad 0,8 Ma lat w klimacie subpolarnym. Fragmenty zagrzebane głęboko w ziemi (nawet do ok. 2 metrów) są przeważnie tak dobrze izolowane od wpływów czynników atmosferycznych, że odnajdowane są w stanie praktycznie nienaruszonym. Głównymi wtórnymi fazami są w różnym stopniu wykrystalizowane wodorotlenki Fe z domieszkami Ni i Cl. Miejscami spotykany jest akaganeit (β-Fe3+O(OH,Cl)). Ponadto, w końcowym etapie wietrzenia zaobserwowano żyłkowe wydzielenia awaruitu (Ni2Fe do Ni3Fe) i/lub niklu rodzimego. Nie odnotowano zwiększenia koncentracji w tych wydzieleniach Ge, jak to ma miejsce w meteorytach moraskich. W warunkach powierzchniowych, nie zabezpieczona przed korozją powierzchnia meteorytu, bardzo szybko ulega zwietrzeniu i w konsekwencji całkowitemu rozpadowi.
6
88%
|
2020
|
tom 11
45-59
EN
A specimen of the ‘Gardnos breccia’ was explored, in which granitic gneiss clasts were found to dominate over a dark matrix. Some clasts retained their cataclastic structure. The matrix of the specimen showed various colours, such as gray, black, and beige, while exhibiting different levels of hardness. In addition, the matrix appeared as an almost isotropic and microcrystalline mass. Quartz, K-feldspar, biotite and plagioclase were identified as the main minerals of the rock. No impact-generated features were observed in the minerals; however, biotite crystals showed decorated kinky bands. In cataclastic clasts, a net of black micro-veins was found, which can be interpreted as pseudotachylite. These veins were composed of a dark non-cohesive glassy mass and carbonaceous micro-aggregates. Furthermore, such carbonaceous aggregated particles were also observed in the black matrix. The white-greenish domains containing isotropic and microcrystalline aggregates of quartz and feldspars showed partial anisotropy. Domains were surrounded by a light recrystallising polycrystalline quartz. Hard black clasts of the matrix and the white-greenish domains showed great similarity in their mineral composition. The results of the X-ray diffraction analyses revealed the minerals as quartz, K-feldspar, muscovite and chlorite (clinochlore). In the white-greenish domains, albite was found as an additional component, whereas it was absent in the black matrix. The black matrix, which was interpreted as a pseudotachylite relic, also seemed to contain allochthonic components. Fluorite, calcite, and Fe-oxides were identified as the secondary minerals that were crystallised in the free spaces of the rock, filling the voids and cracks during the postimpact stage. Oriented glassy spherules, fragments with fluidal texture, and a fragment of the semi-vesicular glassy domain were noted in the specimen, which were probably relics of the suevite breccia. Thus, the analysed breccia seemed to be an intermediate type between the ‘Gardnos breccia’ and the black-matrix breccia and suevite.
PL
Uwagi o okazie ‘brekcji Gardnos’, Norwegia. W egzemplarzu skały znanej jako ‘brekcja Gardnos’ klasty granito-gnejsu dominują nad ciemną matriks. Niektóre klasty zachowały strukturę kataklastyczną. Matriks wykazywała różne kolory, szary, czarny i beżowy, a także różną twardość. Matriks była głównie masą izotropową i mikrokrystaliczną. Kwarc, K-skaleń, biotyt i plagioklaz są głównymi minerałami skały. W minerałach nie zaobserwowano struktur charakterystycznych dla impaktu, jednak w kryształach biotytu odnotowano dekorowane spękania ‘kinky’. W klastach kataklastycznych sieć czarnych mikrożyłek można interpretować jako pseudotachylit. Te żyły składają się z ciemnej, niespoistej szklistej masy, w tym z węglistych mikroagregatów. Zagregowane takie cząstki zaobserwowano również w macierzy czarnej. Biało-zielonawe domeny mikrokrystalicznych agregatów kwarcu i skaleni wykazały częściową anizotropię w partiach izotropowych. W domenach, zielonawe centra stopu skaleniowego otoczone są jasnym, rekrystalizującym polikrystalicznym kwarcem. Twarde czarne klasty macierzy i biało-zielonawe domeny charakteryzują się dużym podobieństwem w składzie minerałów. Analizy dyfrakcji rentgenowskiej wykazały, że były to kwarc, K-skalenie, muskowit i chloryt (klinochlor). W biało-zielonawych domenach dodatkowo występuje albit, nieobecny w czarnej macierzy. Macierz ta interpretowana jako relikt pseudotachylitu zawiera prawdopodobnie również składniki allochtoniczne. Fluoryt, kalcyt i tlenki żelaza były minerałami wtórnymi krystalizowanymi w wolnych przestrzeniach skały i wypełniały puste przestrzenie i pęknięcia w procesach poimpaktowych. Zorientowane szkliste sferule, fragmenty o fluidalnej teksturze i fragment szklistej domeny semi-pęcherzykowej są prawdopodobnie reliktami brekcji suevitu. Analizowana brekcja wydaje się być typem pośrednim między ‘brekcją Gardnos’ a brekcją z czarną matriks i suevitem.
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|
tom 10
74-91
EN
The complex Puchezh-Katunki (PK) structure was created in the area of the Vladimir-Vyatka dislocation zone on the crystalline basement of the East European platform. The crater ca 80 km in diameter is located north of the city Nizhny Novgorod and is covered by thick layers of Mesozoic sediments. Shocked rocks, mainly gneisses, have been described. Recrystallised feldspar-quartz melt is the most common component in specimens of impactites. The melt is preserved in the form of various clasts showing wavy nebulous contacts within the surrounding microcristalline or isotropic matrix. Planar deformation features (PDFs) were observed in the quartz grains, including toasted quartz. Their number ranges from one to three. The PDF lines are limited to the grain boundaries or cross them. A few ‘kinky’ cracks have been noted in the biotite plates. Lobate inter-grain contacts prove that quartz is recrystallised by grain-boundary migration. The recrystallized quartz also occurs in the form of ballen quartz and trydimite. Both types of quartz are numerous in the material under study. Tridymite tiles show patchy extinction. Various matrices formed from rock melts are microcrystalline (clay minerals) and contain fragments of isotropic glass, also in the form of spherules. In matrix, some clasts are in the form of the ballen quartz, sometimes with relics of PDFs. Matrices of recrystallized rock melts are characterised by different colours, number of clasts and are distinctly separated from each other. The melts during the impact process are immiscible. Secondary mineralization is more frequent in the rock melts and less frequent in the metamorphosed gneisses. Magnetite, pyrite and zeolites are the most common secondary minerals.
EN
The researchInvestigations of secondary changes in the tree samples of Pułtusk meteorite, have brought more questions than answers. All the samples have well kept preserved fusion crust, which is built of tree parts. The external part is massive and compact, practically without any fractures whereas the middle part is cracked and porous. The internal part goes into the “black veins zone”. In the middle zone of the crust, skeletal crystals of Fe-Ni spinel, - trevorite, were found. Minerals present within Pułtusk meteorite are differently variously weathered. In At the edges of meteorite the sulphide phases are slightly altered whereas the metallic phases are completely replaced by iron and iron-nickel oxides and hydroxides, which were party removed during cutting. Silicates and chromite are the best preserved minerals.
EN
The study area is located within the Silesia-Cracow zinc-lead ore district. Secondary minerals were collected from the reclaimed zinc-lead underground mine in Bolesław and from the currently operated zinc-lead underground mine Olkusz-Pomorzany. The main goal of investigations was the geochemical and mineralogical comparison of weathering zone developed within horst and tectonic graben. Semi-quantitative chemical composition was determined using the SEM-EDS method and quantitative chemical composition was determined employing the EMP microanalysis. Mineralogical investigations were performed with the XRD. The predominant zinc mineral of weathering zone located within tectonic horst is hemimorphite. No primary and secondary lead minerals were observed in this zone. In contrast, the weathering zone within tectonic graben contains secondary carbonate zinc and lead minerals. These differences could result from pervasive sulfide minerals (especially marcasite) in a graben unit, and limestones which are the main gangue rock of this zinc-lead ore.
PL
Działalność wydobywcza i produkcja koncentratów Pb-Zn prowadzona przez ZGH BOLESŁAW S.A. powoduje powstawanie corocznie ok. 1,5 do 1,6 mln t odpadów poflotacyjnych. Zawierają one znaczne ilości węglanowej skały płonnej (dolomity) oraz metalonośnych minerałów siarczkowych, takich jak: piryt i markasyt, galena, sfaleryt, których koncentracja w odpadach dochodzi do 20 % wagowych. Dynamika procesów uwalniania metali z odpadów, zależy od wielu czynników fizycznych i chemicznych, a także od obecności mikroflory autochtonicznej. Poznanie tych zależności pozwoli na ocenę potencjalnych zagrożeń środowiska. W pracy wykazano, że aktywność metaboliczna utleniających bakterii siarkowych i żelazowych w badanych składowiskach odpadów może prowadzić do przemian fazowych minerałów występujących w odpadach i zwiększenia ładunków metali ciężkich uwalnianych do środowiska. Stężenia metali, w szczególności Cd i Zn w roztworach ługujących pożywek, stymulujące aktywność bakterii siarkowych przewyższają kilkakrotnie lub kilkunastokrotnie poziomy koncentracji metali w pożywkach stymulujących aktywność bakterii żelazowych. Na efektywność (bio)ługowania metali ciężkich (Cd, Pb, Fe, Zn) wywierają wpływ także czynniki abiotyczne, z których istotną rolę odgrywa ustalanie się równowagi kwasowo-zasadowej w obecności alkalicznej skały płonnej.
EN
The mining and production of Zn-Pb concentrates that are conducted by the BOLESŁAW Mine and Metallurgical Plant annually produce approximately from 1.5 to 1.6 m t of flotation tailings. This waste contains aignificant amounts of carbonate gangue (dolomites) and metalliferous sulphide minerals, such as: pyrite and marcasite, galena and sphalerite, whose concentration in the tailings reaches 20 % in terms of weight. The dynamics of metals release from the flotation tailings depends on numerous physical and chemical factors as well as the presence of indigenous microflora. Finding these relations will allow you to estimate potential environmental threats. The paper shows that the metabolic activity of sulphur- and iron-oxidizing bacteria in the examined tailings storages may result in phase transitions of minerals in the flotation tailings and increase in the quantity of heavy metals released into the environment. The concentrations of metals, in particular of Cd and Zn, in leaching solutions of nutrient mediums stimulating the activity of sulphur-oxidizing bacteria exceed the concentrations of metals in leaching solutions stimulating the activity of iron-oxidizing bacteria several times, and more. Finally, abiotic factors also influence the efficiency of heavy metals bioleaching (Cd, Pb, Fe, Zn). Normalization of acid-base balance in the presence of alkaline gangue plays a significant role among these factors.
EN
The abandoned deposit of polymetallic ore in Miedzianka-Ciechanowice is located in the northern part of the Kowary-Czarnów Unit, within the eastern metamorphic cover of the Karkonosze granite. This deposit is formed mainly of hydrothermal veins related to the Karkonosze granite and Intra-Sudetic Fault. Lenses-forming contact-metasomatic ores are also present. The ore assemblages are rich in Cu, and poor in Pb, Ag, As and Fe. The Miedzianka- -Ciechanowice deposits were mined from the early Middle Ages to the middle of the 20th
EN
The former gold and silver mine of Breiner, is located in the village of Băiuţ, in the mining area of Băiuţ-Tibleş (Maramureş, Romania). The local polymetallic occurrences are characterized by a rich sulfide (Cu, Pb, Zn sulfides/sulfosalts) and arsenic mineralization. While the primary mineralization is relatively well known, the diverse paragenesis of second- ary mineralization has never been the subject of detailed research. Based on diffraction studies, several species of weathered minerals have been identified, most of which have never been reported in the study area before. The dominant minerals in the mine belong to the melanterite and halotrichite groups. The occurrence of rare phases on a global scale has also been observed - zaherite Al12(SO4)5(OH)26 20H2O, tooeleite Fe6(AS3+O3)4(SO4)(OH)44H2 and wattevilleite - a species with uncertain chemistry, possibly Na2Ca(SO4)24H2O. The formation of these parageneses is related to currently occurring weathering processes of primary ore mineralization that undergoes decomposition under low pH conditions.
EN
The polymetallic Radzimowice deposit is located in the vicinity ofRadzimowice village, about 20 km east of Jelenia Góra (Western Sudetes, Poland). The deposit consists of several ore veins. The primary ore assemblage is represented by arsenopyrite, pyrite and chalcopyrite, and less common galena, sphalerite, Cu-Pb-Sb sulphosalts of Cu andPb, and native gold. The mining activity in this area started in the mid-12th century and lasted until the mid-20th century. This paper presents general information about typical parageneses of secondary minerals occurring in the oxidation zone of the Radzimowice deposit. Based on the mineralogical investigations, 43 secondary mineral species have been recognized. Such a rich assemblage of secondary minerals makes the oxidation zone one of the most interesting formations of this kind in Poland. Phosphates (pseudomalachite, phosphosiderite) and sulphides (covellite, chalcocite) of copper were ascertained in the near-surface part of the supergene zone. Secondary lead minerals (cerussite, pyromorphite and mimetite) were found only in medieval dumps. Phosphates and sulphides of Cu and supergene lead minerals belong to sub-recent secondary parageneses. Since the end of local mining activity in 1957, the intensive weathering processes caused the decomposition of ore minerals in the mine galleries, producing recently forming associations of new minerals. The first mineral paragenesis is represented by recently formed arsenates. Kankite, scorodite and zykaite are the most widespread constituents of this assemblage. Large accumulations ofpitticite, forming stalagmites up to 10 cm in length, are sometimes found in old mine galleries. In those parts of the abandoned mine, where pyrite is a dominant primary mineral, huge accumulations of the minerals related to acid mine drainage are present. Schwertmannite, ferrihydrite and poorly crystalline goethite are the main representatives of this paragenesis. Associations of basic copper sulphates are present in all parts of the abandoned mine. Langite, posnjakite, brochantite and devilline are the most common minerals of this assemblage. Sulphates of Cu and Al (chalcoalumite and cyanotrichite), native copper, cuprite and malachite are locally found to coexist with these phases. Precipitations of secondary minerals play an important role in the retention and liberation of considerable amounts of toxic elements. Dissolution ofthese phases can result in the release ofarsenic and heavy metals into the groundwater and in the migration ofthese elements into the environment.
EN
The theoretical and experimental studies resulted in establishing regularities in the distribution of secondary minerals and their associations in metasomatically altered diamond-bearing kimberlites and products of their processing. Based on integrated mineralogical research, it was found out that the composition of the altered kimberlites and the fine-dispersed clayey slurries formed during their processing constituted the basis of hydrophilic formations on the surface of diamond crystals not recovered by the methods of grease and froth separation. Particles of these minerals concentrate in fine-dispersed slurry products of kimberlite ore processing, interact with the crystal surface, reduce their hydrophobic properties and, accordingly, recovery in processes of grease and froth separations into concentrates.
PL
Przeprowadzono analizę teoretyczną i badania eksperymentalne w celu ustalenia prawidłowości w rozkładzie minerałów wtórnych i ich związków w metasomatycznie zmienionych diamentach kimberlitowych i produktach ich przetwarzania. Na podstawie zintegrowanych badań mineralogicznych stwierdzono, że zmienione kimberlity i drobnoziarniste produkty ich metamorfozy stanowiły hydrofilowe formacje na powierzchni kryształów diamentu, które nie zostały odzyskane metodami flotacji pianowej. Cząstki tych minerałów koncentrują się w drobno zdyspergowanych produktach przerobu rudy kimberlitowej, oddziałują z powierzchnią kryształu, redukują ich właściwości hydrofobowe i odpowiednio przechodzą w procesach flotacji do koncentratów.
EN
The study presents fifteen oxygen-bearing secondary minerals of bismuth from the north-eastern part of the Variscan Karkonosze granitoid pluton in the northern zone of the Bohemian massif. The minerals were investigated by optical, electron microprobe, classic chemical, XRD, IR absorption and fluid inclusion methods. The late, very low temperature epithermal solutions most probably caused formation of sillénite, kusachiite, bismoclite, bismutite, beyerite, kettnerite, pucherite, schumacherite, namibite and eulytite. Solutions dominated by supergene (meteoric) waters were the parents for bismite, russellite, koechlinite, ximengite and walpurgite. The paper also contains information on early research on the investigated minerals.
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