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Romero Baylón, Alfonso, Silvana Flores Chávez e Walter Arévalo. "Tratamiento de efluentes de la industria minera con dolomita". Industrial Data 13, n.º 1 (22 de março de 2014): 085. http://dx.doi.org/10.15381/idata.v13i1.6174.
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El artículo presenta una metodología de tratamiento de las aguas ácidas obteniendo la remediación de los efluentes de la industria minera, basado en el empleo de la dolomita tratada que permite reducir las concentraciones de los iones de metales pesados disueltos en los efluentes minero-metalúrgicos a valores altos de reducción de los metales pesados, los cuales son indicadores de una mejora en la calidad de agua de los desechos industriales provenientes, principalmente, de procesos metalúrgicos de plantas concentradoras. Esta técnica de tratamiento resuelve el problema de generación de efluentes metalúrgicos con el empleo de la dolomita, mineral no metálico de carbonato doble de calcio y magnesio (CaCO3. MgCO3), que se comporta como un efectivo reactivo de remediación, debido a las propiedades fisicoquímicas de la neutralización de la acidez de aguas ácidas, así como la adsorción de iones metálicos disueltos en las aguas ácidas. Asimismo, la aplicación de este tratamiento de remediación propone establecer una metodología de trabajo que desarrolle una tecnología de limpieza a nivel de laboratorio, con perspectivas a desarrollar la misma tecnología a nivel de planta piloto, con el posterior desarrollo de una planta de tratamiento de remediación a nivel industrial.
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Soares, R. A. L., R. M. do Nascimento, C. A. Paskocimas e R. J. S. Castro. "Avaliação da adição de dolomita em massa de cerâmica de revestimento de queima vermelha". Cerâmica 60, n.º 356 (dezembro de 2014): 516–23. http://dx.doi.org/10.1590/s0366-69132014000400009.
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A dolomita é um mineral encontrado em abundância no estado do Piauí, ao mesmo tempo é desconsiderada pela indústria cerâmica. A sua formação química-mineralógica aponta para uma potencialidade de aplicação em massa cerâmica de revestimento, devido à presença de óxidos fundentes e outros capazes de formar novas fases cristalinas que contribuem na melhoria da estabilidade dimensional e resistência mecânica dos corpos cerâmicos. Desta forma, o presente trabalho tem como objetivo avaliar a potencialidade do uso de um carbonato dolomítico na produção de cerâmica de revestimento de base vermelha. Para isso foram caracterizadas uma massa cerâmica usada na produção de revestimento semiporoso e dolomita oriunda de uma jazida piauiense. O carbonato foi adicionado à massa industrial em diferentes teores e as formulações foram queimadas em três temperaturas: 1080 ºC, 1120 ºC e 1160 ºC. Foram realizados nos corpos de prova queimados ensaios tecnológicos de retração linear, absorção de água, massa específica aparente e resistência mecânica. A microestrutura foi avaliada através de análise por difração de raios X e microscopia eletrônica de varredura. Os resultados mostraram potencialidade da aplicação da dolomita piauiense em massa de revestimento cerâmico.
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Amorim, K. B., e R. S. Angélica. "Mineralogia e geoquímica da ocorrência de palygorskita de Alcântara, bacia de S. Luís-Grajaú, Maranhão". Cerâmica 57, n.º 344 (dezembro de 2011): 483–90. http://dx.doi.org/10.1590/s0366-69132011000400017.
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A Formação Alcântara (bacia de São Luis-Grajaú, região de Alcântara, MA) é constituída por pelitos, arenitos e dolomitos. Esses litotipos representam uma sucessão progradacional de depósitos de laguna/washover e canal de maré sobrepondo-se a depósitos de shoreface gerados por processos de tempestade. O presente trabalho tem como objetivo principal à caracterização mineralógica e geoquímica dos argilominerais que ocorrem nos níveis pelíticos da Formação Alcântara, especialmente a palygorskita. Foi descrito e amostrado um perfil geológico na praia da Baronesa, na cidade de Alcântara, MA, no qual foram coletadas 8 amostras, que após a preparação em laboratório, foram submetidas a análises mineralógicas e químicas por difração de raios X, fluorescência de raios X, análises térmicas e microscopia eletrônica de varredura. Os resultados mostraram que o perfil da praia da Baronesa é composto por arenitos na base, seguido de pelitos dominantes, com intercalações de dolomitos. Nos pelitos, foram descritos uma ampla assembléia de argilominerais, em ambiente lagunar, com variações no conteúdo de palygorskita, clorita, illita, esmectita e traços de caulinita. Observam-se ainda traços de dolomita, calcita e feldspatos. Os teores de palygorskita e dolomita (níveis dolomíticos) são acentuados, sugerindo que as condições climáticas durante o período de deposição foram áridas a semi-áridas. Duas gerações de palygorskita foram descritas: uma na forma de bolsões ou acumulações macroscópicas nos níveis pelíticos ricos em esmectita, freqüentemente descritas na literatura, e outra na forma maciça, como o mineral dominante dos níveis pelíticos superiores do perfil da praia da Baronesa. Essa segunda geração está sendo descrita pela primeira vez, neste trabalho, podendo constituir em níveis métricos e que podem revelar interesse econômico.
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González-Fuentes, José Antonio, Daniela Jiménez-López, Alberto Sandoval-Rangel, Armando Hernández-Perez, Julia Medrano-Macías e Pablo Preciado-Rangel. "Efecto de enmiendas minerales sobre el contenido mineral y antioxidantes en frutos de frambuesa//Effect of mineral amendments on raspberry fruits mineral content and antioxidants". Biotecnia 22, n.º 1 (18 de outubro de 2019): 48–55. http://dx.doi.org/10.18633/biotecnia.v22i1.1124.
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Con el propósito de que plantas de frambuesa cultivadas en sustrato de peat moss y perlita, adquirieran una mayor cantidad de nutrientes minerales de los que comúnmente obtienen de una solución nutritiva completa en cultivo sin suelo, aquí se reporta el efecto de enriquecer el medio de crecimiento (sustrato) con diferentes moliendas de rocas minerales ricas en nutrientes (roca fosfórica, riolita, diatomita, dolomita, zeolita y harina de basalto) de las cuales se aplicaron 15 g por tratamiento a cada planta de frambuesa (Rubus ideaus L.) variedad fx1522. Con las aplicaciones de las diferentes rocas molidas se incrementó en frutos el contenido mineral de K, P, Ca, Mg, S, y Cu en 27, 27, 42, 33 y 44 %, respectivamente. Con respecto a la actividad enzimática de la catalasa se encontró que con riolita, diatomita y zeolita aumentaron en 54, 45 y 34 % respectivamente comparados con el testigo. La actividad de superóxido dismutasa y el contenido de vitamina C no se vieron afectadas por los tratamientos. El tratamiento con zeolita incrementó los compuestos fenólicos en un 23 %.ABSTRACTIn order for raspberry plants cultivated in an inert growing medium of peat moss and perlite acquire a greater amount of mineral nutrients than they commonly obtain from a complete nutrient solution in soilless culture, here we report the effect of amending the soilless growing medium with different ground mineral rocks (mills) rich in nutrients (phosphate rock, rhyolite, diatomite, dolomite, zeolite and basalt flour) of which 15 g were applied per treatment to each raspberry plant (Rubus ideaus L.) variety fx1522. The applications of different ground rocks increased the fruits K, P, Ca, Mg, S, and Cu mineral contents by 27, 27, 42, 33 and 44 %, respectively. Regarding the CAT enzymatic activity, it was found that the treatments with riolite, diatomite and zeolite increased 54, 45 and 34 % respectively when compared against the control plants. Superoxide dismutase activity and vitamin C content were not altered by the treatments. The treatment with zeolite increased the phenolic compounds by 23%.
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Sena, Mábia Ruana Silva, e José Agnelo Soares. "EFEITO DA COMPOSIÇÃO MINERAL SOBRE AS PROPRIEDADES PETROFÍSICAS DE ROCHAS CARBONÁTICAS DA BACIA DO ARARIPE". HOLOS 1 (18 de julho de 2017): 185. http://dx.doi.org/10.15628/holos.2017.5159.
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As rochas carbonáticas apresentam grande importância como reservatórios de hidrocarbonetos em várias bacias sedimentares do mundo. Visando esta importância foi realizado o estudo em rochas carbonáticas da Bacia do Araripe que é a maior das bacias interiores do Nordeste, com o objetivo de avaliar a influência da composição mineral nas propriedades petrofísicas destas rochas. Foram utilizadas quatro amostras de rochas, determinando as propriedades petrofísicas através de ensaios convencionais e a composição mineralógica das rochas através da análise de imagens digitais de microtomografia de raios x (mCT). Os resultados alcançados para a simulação da composição mineral indicam que as amostras são formadas essencialmente por calcita e/ou dolomita. Os resultados mostram que os teores dos minerais principais controlam as propriedades petrofísicas, especialmente a densidade e as velocidades elásticas. No entanto, outros fatores também podem afetar substancialmente as velocidades elásticas, como a porosidade, o tipo de porosidade (vugular ou intergranular) e o percentual de microporosidade.
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Flores Chávez, Silvana, Alfonso Romero Baylón e David Martínez Aguilar. "Tecnología de clasificación fina de mineral metálico y no metálico". Industrial Data 12, n.º 1 (22 de março de 2014): 027. http://dx.doi.org/10.15381/idata.v12i1.6081.
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El artículo describe una visión general sobre el uso del Cyclosizer, utilizado principalmente para la realización de pruebas experimentales de minerales metálicos y no metálicos en el procesamiento de minerales tales como: mineral aurífero y mineral de dolomita, respectivamente. El cyclosizer es un elutriador que separa una muestra en fracciones de tamaño específico por una técnica que depende de las fuerzas producidas por las velocidades relativas de las partículas y del fluido de elutriación. Difiere de una elutriación convencional en la que la acción de elutriación toma lugar en un ciclón hidráulico donde el fluido está girando y las fuerzas centrífugas muchas veces, debido a la gravedad, están actuando sobre las partículas. Los modelos de fluidos dentro del ciclón son estables y los cambios en las condiciones del ambiente no son muy críticas como el procedimiento convencional para elutriación. También las altas fuerzas cortantes que son desarrolladas en el ciclón sobrepasan cualquier tendencia natural para que flocule el material fino y una excelente disposición de las partículas sea asegurada.
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Δήμου, Ε., e Κ. Κούκουζας. "MlNERALOGICAL STUDY OF Mg-SKARNS WITH CLINOHUMITE AT THE OMERLI SITE AGGISTRO, SERRES". Bulletin of the Geological Society of Greece 36, n.º 1 (1 de janeiro de 2004): 436. http://dx.doi.org/10.12681/bgsg.16732.
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Mg-skam occurrences located in the dolomitic marbles at the Omerli site near Aggistro are studied. The dolomitic marbles are gradually enriched in metasomatic minerals, up to the full replacement and the formation of cohesive lenticular beds of skarns in the marbles. The aplito-pegmatitic veins traversing the surrounding marbles as well as the granodiorite occurring in the broader area of Ahladohoho, are considered responsible for the phenomena of thermal metamorphism and metasomatism in the dolomites. On the basis of mineralogical analytical methods (optical microscopy, X-Ray diffraction, microanalysis) the following metasomatic minerals in decreasing order, have been determined: Clinohumite (Mg, Fe +)Q (Si04)4(F,OH)2, forsterite Mg2Si04, spinel MgAb04, hornblende-pargasite NaCa2 (MgFe% AI(SÌ6AI2)022(F,OH)2, clinochlore (MgFe2+)AI(SÌ3AI)Oi0(OH)8, phlogopite KMg3SÌ3AIOio(F, OH)2, dolomite, calcite. The mineral chemistry and petrography of the above assemblages lead to the conclusion that the skarns at Omerli site constitute pure metasomatic concentrations at the expense of the dolomites, with addition of elements from external thermal source and removal of elements from the hosting dolomites. It is, therefore, an open chemical system and not an iso-chemical one.
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LUCIANO, Rejane Lima, e Antonio Misson GODOY. "LITOGEOQUÍMICA E QUÍMICA MINERAL DAS ROCHAS METACARBONATÍTICAS DE ANGICO DOS DIAS, DIVISA BAHIA/PIAUÍ, BRASIL." Geosciences = Geociências 37, n.º 1 (4 de abril de 2018): 99–119. http://dx.doi.org/10.5016/geociencias.v37i1.12920.
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As rochas do Complexo Metacarbonatítico de Angico dos Dias ocorrem na região do extremo noroeste do estado da Bahia e são constituídas por metacarbonatitos, metassienitos variados, metapiroxenitos, metadioritos, tremolititos, biotitito, metalamprófiros, fenitos e apatititos, que constituem depósito secundário de fosfato residual. Os metacarbonatitos originam um acamamento cumulático, definido por níveis diferenciados em apatita, minerais ferromagnesianos e magnetita, que permitem individualizar cinco tipos petrográficos: o apatita metacarbonatito; olivina-apatita metacarbonatito; flogopita-apatita-olivina metacarbonatito; olivina-apatita-biotita/flogopita metacarbonatito e metacarbonatito silicificado. Dados petrográficos e de química mineral apontam a presença de: calcita com exsolução de dolomita; fluorapatita; pseudomorfos de olivina alteradas para serpentina, tremolita, antofilita e magnetita; flogopita; badeleíta; exsolução de ilmenita em magnetita que se altera para hematita; pirrotita; pirita; calcopirita; sulfatos como celestita, barita e baritocelestita e oxi-hidróxidos do tipo goethita e lepidocrocita. O intemperismo dos carbonatitos encontra-se associado com as carapaças ferruginosas e/ou silicificadas, além de concentrar apatita, pode originar alumino-fosfatos do grupo da crandalita, goyazita, gorceixita, plumbogumita, florencita. As associações minerais ígneas anidras e metamórficas de alto grau apresentam-se superimpostas por paragêneses retrometamórficas em fácies xisto verde alto. Dados geoquímicos classificam as rochas metacarbonatíticas principalmente como calciocarbonatitos e aquelas intensamente hidrotermalizadas são classificadas como ferrocarbonatitos e magnesiocarbonatitos
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Soares de Almeida, Gabriel, Eduardo Duarte Marques, Francisco José da Silva, Claiton Piva Pinto e Emmanoel Vieira Silva-Filho. "APPLICATION OF pXRF (FIELD PORTABLE X-RAY FLUORESCENCE) TECHNIQUE IN FLUVIAL SEDIMENTS GEOCHEMICAL ANALYSIS – BULE STREAM, MINAS GERAIS STATE, BRAZIL". Journal of Sedimentary Environments 4, n.º 2 (11 de junho de 2019): 143–58. http://dx.doi.org/10.12957/jse.2019.43279.
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A new methodology based on a portable X-ray fluorescence (pXRF) was applied in this work to analyze the geochemical dispersion halo of a sulfide mineralization along the Bule Stream sediments (Ouro Branco, Minas Gerais State, Brazil). The study area, located in the Iron Quadrangle (QF), has an important sulfide occurrence of antimony and zinc, which was explored between 1920s and 1930s. Stream sediment samples were collected along the Bule Stream and from some of its tributaries. Aluminum, Fe, Ca, Mg, Mn and Ti contents were obtained by the pXRF “mining mode” and quantified in percentage (%), while the results for Cu, Zn, Pb, As, Cr, Ag, Sb and Sr were carried out by the pXRF “soil mode”, quantified in parts per million (ppm). The statistical treatment of data by Spearman correlation based on geochemical data and some sediment features were discussed, such as the geochemical affinities between the analyzed elements and supergene processes which control the elemental dispersion. Aluminum, Ca and Mg contents were compared with that of the Upper Continental Crust (UCC), since the composition of the Bule Stream sediments should be related to the composition of the source rocks. The results indicate that the Al contents reflect the surrounding soil maturity. The concentrations of Ca and Mg increase in weathered resistant mineral phases, mainly dolomite. The Fe enrichment is associated with geological units containing this element, such as dolomite/ferruginous itabirites (BIF). The high Mn content is related to the QF unity with larger dolomite occurrence (Gandarela Formation). Secondary environmental characteristics can justify the enrichment of Zn and Cu in the study area. All types of rocks have significant concentration of Cr. The comparison of the elemental concentrations of Bule Stream sediments with the average concentration of the elements in the Earth's upper crust (UCC) reveals intense weathering rate of the parent rocks characterized by high maturity of the geological material, enrichment of Fe and Mn and most of the analyzed trace metals. The results of an enrichment factor with three different normalizers (Al representing clay minerals; Fe + Mn representing oxides/hydroxides and; Ca + Mg representing carbonates) indicate that the carbonate phase is the main conveyor of trace elements. APLICAÇÃO DA TÉCNICA DE pXRF NA ANÁLISE GEOQUÍMICA DE SEDIMENTOS FLUVIAIS – RIBEIRA BULE, ESTADO DE MINAS GERAIS, BRASIL ResumoUma nova metodologia baseada na fluorescência de raios X portátil (pXRF) foi aplicada neste trabalho para analisar o halo de dispersão geoquímica de uma mineralização de sulfeto ao longo dos sedimentos Córrego do Bule (Ouro Branco, Minas Gerais, Brasil). A área de estudo, localizada no Quadrilátero Ferrífero (QF), tem uma importante ocorrência de sulfeto de antimônio e zinco, que foi explorada entre as décadas de 1920 e 1930. Amostras de sedimentos fluviais foram coletadas ao longo do Córrego do Bule e em de alguns dos seus afluentes. Os teores de Al, Fe, Ca, Mg, Mn e Ti foram obtidos por pXRF em “mining mode” e quantificados em porcentagem (%), enquanto os resultados de Cu, Zn, Pb, As, Cr, Ag, Sb e Sr foram obtidos pelo pXRF em “soil mode” e foram quantificados em partes por milhão (ppm). Este trabalho analisa o tratamento estatístico dos dados por correlação de Spearman com base em dados geoquímicos e algumas características do sedimento, assim como as afinidades geoquímicas entre os elementos analisados e os processos supergênicos que controlam a dispersão dos elementos químicos. Os teores de Al, Ca e Mg foram comparados com os da Crosta Continental Superior (UCC), uma vez que a composição dos sedimentos do Córrego do Bule devem estar relacionados à composição das rochas geradoras. Os resultados indicam que o teor de Al reflete a maturidade do solo ao redor. As concentrações de Ca e Mg aumentam nas fases minerais resistentes às intempéries, principalmente dolomita. O enriquecimento de Fe está associado a unidades geológicas que contêm esse elemento, como o itabirito dolomítico e/ou dolomito ferruginoso (BIF). O alto teor de Mn está relacionado à unidade de QF com maior ocorrência de dolomita (Formação Gandarela). Características ambientais secundárias podem justificar o enriquecimento de Zn e Cu na área de estudo. Todos os tipos de rochas possuem concentração significativa de Cr. A comparação das concentrações elementares dos sedimentos da corrente de Bule com as concentrações médias dos elementos da Terra (UCC) revela intensa taxa de intemperismo das rochas-mãe caracterizadas pela alta maturidade do material geológico, enriquecimento de Fe e Mn e a maioria dos metais traço analisados. Os resultados de um fator de enriquecimento com três diferentes normalizadores (Al representando minerais argilosos; Fe + Mn representando óxidos / hidróxidos e; Ca + Mg representando carbonatos) indicam que a fase carbonatada é o principal transportador de elementos químicos.Palavras-chave: Geoquímica. Quadrilátero de Ferro. Sedimentos. Fluorescência Portátil de Raios X. Metais. Fatores de Enriquecimento.
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Chen, Xiaoquan, Fengcun Xing, Shu Jiang, Yongchao Lu, Zhongrong Liu, Lei Pan e Huarui Hu. "Origin and formation model of Eocene dolomite in the upper Niubao Formation of the Lunpola Basin, Tibetan Plateau". Interpretation 9, n.º 3 (1 de agosto de 2021): SF11—SF22. http://dx.doi.org/10.1190/int-2020-0195.1.
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Using fresh core samples, we have determined the origin and formation process of Eocene lacustrine dolomites in the Tibetan Plateau through petrological, mineralogical, and geochemical analyses. Dolomitic rocks were collected from the upper member of the Eocene Niubao Formation in the Lunpola Basin, consisting of dolomitic mudstone, argillaceous dolomite, dolomite-bearing mudstone, and mud-bearing dolomite. These dolomites are dominated by aphanotopic and microcrystalline dolomites, with minor amounts of euhedral or subhedral powder- and fine-crystalline dolomites. Carbon and oxygen stable isotopes, combined with ubiquitous gypsum in study area, indicate a semisaline continental lake under strong evaporative conditions. The revealed relatively high temperature of the dolomitization (33.8°C–119.1°C), combined with hydrothermal minerals such as cerous phosphate and barite, reflect the participation of dolomite from hot fluids. Moreover, the inferred dolomitization temperatures decrease gradually toward the center of the lake basin, suggesting the resurgence of hydrothermal fluids along a fault zone on the lake margin. This proves that frequent thermal events occurred at the boundary fault of the Lunpola Basin margin during early Himalayan orogenesis. In addition, Jurassic carbonates interacting with hydrothermal fluids, as well as strong evaporation conditions, likely provided favorable conditions for the formation of primary lime sediments. A rich source of [Formula: see text] brought by volcanic ash, hydrothermal fluids, and the Jurassic carbonates then created conditions for dolomitization during the depositional period. Strong evaporation under a relatively hot climate enhanced penecontemporaneous dolomitization, thus forming dolomite. Tibetan Plateau was under arid to semiarid climate conditions, and there was a widespread distribution of dolostones in western, central, and northern China during the Eocene period. The hydrothermal dolomites of the upper Niubao Formation testify for active hot springs, whereas lacustrine dolomite imply arid or semiarid climates during the Eocene, in the early stages of Himalayan orogenesis.
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ΚΑΝΤΗΡΑΝΗΣ, Ν., Α. ΤΣΙΡΑΜΠΙΔΗΣ, Α. ΦΙΛΙΠΠΙΔΗΣ, Α. ΚΑΣΩΛΗ-ΦΟΥΡΝΑΡΑΚΗ e Β. ΧΡΗΣΤΑΡΑΣ. "Industrial uses of carbonate rocks from Thassos island (Greece)". Bulletin of the Geological Society of Greece 34, n.º 3 (1 de janeiro de 2001): 1147. http://dx.doi.org/10.12681/bgsg.17175.
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The carbonate rocks of Thassos Island are holocrystalline and present sparitic texture. The dolomites have smaller crystall size (0.7-1.6 mm) than the calcitic marbles (0.8-2.2 mm). In the dolomites except the synonymous mineral, calcite (1-10%) and traces of quartz, feldspars and micas are present. In the calcitic marbles except of the calcite, dolomite (2-28%), micas (1-6%) and occasionally feldspars, clay minerals and goethite occur. The results of chemical analysis agree with the mineralogical ones, as well as with the percentage of the isnoluble residue. The dolomites appear purer than all other marbles of the island. They most often contain Si02 (up to 0.88%). Beyond the decorative applications the calcitic marbles of Thassos are mainly suitable for the production of aggregates with any size requirement, cement and probably container glasses, for environmental uses and as soil conditioners. Respectively, the dolomitic marbles are suitable for the production of fertilizers and probably of container glasses and as fillers or whitenings in paper, paint and rubber industries.
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Monte, Marisa Bezerra de Mello, e Danielle Andrade Pimentel. "Influência dos Finos de Dolomita e da Dissolução de Minerais de Cálcio no Desempenho da Flotação de Apatita / Influence of Dolomite Fines and Calcium Mineral Dissolution on Apatite Flotation Performance". Brazilian Journal of Development 7, n.º 4 (13 de abril de 2021): 38090–105. http://dx.doi.org/10.34117/bjdv7n4-323.
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Srinivasan, Sesha, Dominic Dodson, Mc Ben Joe Charles, Scott L. Wallen, Gary Albarelli, Ajeet Kaushik, Nicoleta Hickman, Ganga Ram Chaudhary, Elias Stefanakos e Jaspreet Dhau. "Energy Storage in Earth-Abundant Dolomite Minerals". Applied Sciences 10, n.º 19 (24 de setembro de 2020): 6679. http://dx.doi.org/10.3390/app10196679.
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Dolomite, a calcium magnesium mineral (CaMg(CO3)2), is considered an undesirable accompanying mineral in the phosphoric acid production process and, as such, large quantities of this mineral are available in Florida. This study is aimed toward the characterization of the high-concentration phosphatic dolomite pebbles (handpicked dolomites) received from the Florida Industrial and Phosphate Research Institute (FIPR) and investigate their feasibility for thermochemical energy storage (TCES). The chemical composition, structural and microstructural characteristics of commercial and handpicked dolomite minerals was studied using a variety of techniques such as X-ray Fluorescence (XRF), Fourier-transform infrared spectroscopy (FTIR), and an automated mineralogy Automated SEM-EDX Mineralogy (or automated scanning electron microscopy) with energy dispersive X-rays spectrometer (SEM-EDX), which confirmed the phosphatic pebbles received contains dolomite (CaMg(CO3)2) phase in a high percentage. Particle size and the surface area were measured using XRD and N2 adsorption, the Brunauer–Emmett–Teller (BET) methods. Thermogravimetric analysis (TGA) was used to determine the activation energy for the calcination and re-carbonation reactions of the dolomite pebbles in nitrogen (N2) and carbon dioxide (CO2) atmospheres at temperatures up to 800 °C. The present results exhibit, for the first time, the potential for using abundant, high phosphatic concentration dolomite possessing long-term cycling behavior for thermochemical energy storage applications in Concentrated Solar Power (CSP) plants.
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Krogulec, Ewa, Katarzyna Sawicka, Sebastian Zabłocki e Ewa Falkowska. "Mineralogy and Permeability of Gas and Oil Dolomite Reservoirs of the Zechstein Main Dolomite Basin in the Lubiatów Deposit (Poland)". Energies 13, n.º 23 (5 de dezembro de 2020): 6436. http://dx.doi.org/10.3390/en13236436.
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Permeability characterizes the ability of rocks to store and transport natural gas, crude oil and reservoir fluids. Permeability heterogeneity of reservoir rocks, including dolomites, results from overlapping geological and physicochemical processes. The permeability study of gas-bearing dolomites was carried out on the Lubiatów hydrocarbon deposit (Poland), located at the Ca2 carbonate platform toe-of-slope, which is a prospective area for hydrocarbon exploration in Europe. Due to the complicated rock textures and overlapping alteration processes, including secondary crystallization or dissolution of minerals, the permeability of the deposit is variable. Studies of dolomites from a depth of 3242–3380 m show high mineralogical diversity; the percentage of dolomite ranges from 79% to 95% with a variable content of other minerals: anhydrite, gypsum, quartz, fluorite, plagioclase and clay minerals. The porosity variability ranges from 4.69% to 31.21%, depending on the measurement method used. The mean permeability value is 35.27 mD, with a variation range of 0.9 to 135.6 mD. There is neither change in permeability with depth and mineral composition, nor a direct relationship between porosity and permeability.
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Chatalov, Athanas. "Origin of fabric-selective dolomitization recognizable in the field: two case studies from Anisian carbonate rocks in the western Balkanides". Geologica Balcanica 47, n.º 1 (maio de 2018): 43–60. http://dx.doi.org/10.52321/geolbalc.47.1.43.
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The origin of dolomitized burrows (Cruziana ichnofacies) in limestones and dolomitic layers in limestone-dolostone ribbon rocks was studied on the basis of petrography, X-ray diffractometry, geochemical data and isotope signatures of the dolomites. Selective dolomitization of the burrows with a local source of Mg occurred in a near-surface setting from non-evaporitic solutions with low Mg/Ca ratio. The low-temperature precipitation of non-stoichiometric (with Ca excess) dolomite was microbially mediated and controlled by bacterial sulphate reduction. The carbon for dolomite formation was largely derived from seawater and/or dissolution of precursor carbonate sediments, and partly derived from the decomposition of organic matter. Selective dolomitization of primarily argillaceous carbonate layers in the ribbon rocks was mainly associated with an autochthonous source of Mg. Clay mineral transformations (i.e., illitization of smectite) at intermediate burial depths supplied Mg ions for the formation of Ca-rich (locally ferroan) dolomite. However, differential diagenesis of the originally clay-rich and clay-poor layers may also have favoured early dolomite precipitation, whereupon contemporaneous seawater was the primary Mg source during shallow burial. The obtained results show that various factors control the formation of fine-grained, non-stoichiometric dolomite with macroscopically recognizable fabric-selective character of replacement.
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Womer, M. B. "HYDROCARBON OCCURRENCE AND DIAGENETIC HISTORY WITHIN PROTEROZOIC SEDIMENTS, McARTHUR RIVER AREA, NORTHERN TERRITORY, AUSTRALIA". APPEA Journal 26, n.º 1 (1986): 363. http://dx.doi.org/10.1071/aj85031.
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The stratigraphy of the Proterozoic in the McArthur River area of Northern Territory consists of the basal, non-economic Tawallah Group, overlain unconformably by dolomitic carbonates and clastics of the McArthur Group, in turn overlain disconformably by Roper Group clastics. Several shows of tarry to brittle bitumen have been reported in sandstones of the Roper Group and in dolomites of the McArthur Group.In thin sections, the bitumen commonly displays shrinkage cracks, apparently associated with the loss of volatiles. Secondary minerals are observed infilling some of the cracks, indicating those phases of diagenesis which occurred subsequent to breaching of the hydrocarbon bearing reservoir. Additionally, the contact relationships of bitumen with the secondary minerals indicate a relatively early migration of hydrocarbons into the reservoir rocks.The inferred sequence for the McArthur Group dolomites is: early dolomitization and silicification, formation of vuggy (vadose) porosity, authigenic deposition of chalcedony at shallow burial depth, cementation by quartz at deep burial depth, migration of hydrocarbons (contemporaneous with sulphide formation), breaching of the reservoir, degradation of hydrocarbons, and deposition of sparry dolomite cement. The inferred sequence of diagenesis for Roper Group clastic reservoirs in this area is: authigenic deposition of minor quartz and illite cement, migration of hydrocarbon, breaching of the reservoir, major authigenic deposition of quartz and illite, degradation of hydrocarbon, and cementation by dolomite, hematite, and kaolinite.
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Holanda, Werlem, Anderson Costa dos Santos, Camila Cardoso Nogueira, Luiz Carlos Bertolino, Sérgio Bergamaschi, René Rodrigues e Diego Felipe da Costa. "EFFECTS OF IGNEOUS INTRUSION ON THE MINERALOGICAL CONTENT OF IRATI FORMATION, PARANÁ BASIN, IN SAPOPEMA (PR), SOUTHERN BRAZIL". Journal of Sedimentary Environments 4, n.º 3 (28 de setembro de 2019): 350–60. http://dx.doi.org/10.12957/jse.2019.45796.
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Igneous intrusions in sedimentary basins are commonly related with mineralogical association changes in host-rock. At Sapopema region (Paraná State, southern Brazil), an extensive diabase sill (associated to Serra Geral Formation) was emplaced in pelitic-carbonate succession during post-Triassic. The sedimentary host-rock association includes mostly shale, siltstone and carbonate of the Permian Irati Formation. X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) data revealed that heat transfer was not enough to cause modifications in mineral assemblage of the Taquaral Member (quartz + albite + muscovite + illite + kaolinite + chlorite). However, mineralogical content from Assistência Member presented changes probably caused by the intrusion of diabase sill (talc + pyrophyllite + calcite). Talc and calcite were formed due to the reaction between dolomite and quartz, while pyrophyllite was the product of reaction between kaolinite and quartz. EFEITOS DA INTRUSÃO IGNEA NA COMPOSIÇÃO MINERALÓGICA DA FORMAÇÃO IRATI, BACIA DO PARANÁ, SAPOPEMA (PR), SUL DO BRASIL ResumoAs intrusões ígneas em bacias sedimentares dão origem em geral a alterações mineralógicas da rocha hospedeira. Na região de Sapopema (Estado do Paraná, sul do Brasil), uma extensa soleira de diabásio (associada à Formação Serra Geral) pós-Triássica, foi intrudida numa sucessão sedimentar constituída por pelitos e carbonatos. A associação de rochas sedimentares hospedeiras, era principalmente constituída por folhelho, siltito e carbonato da Formação Irati, do Permiano. Dados de difração de raios X (DRX), microscopia eletrônica de varredura (MEV) e espectroscopia de energia dispersiva (EDS) revelaram que a transferência de calor não foi suficiente para causar modificações na composição mineralógica do membro Taquaral (quartzo + albita + moscovita + ilita + caulinita + clorita). No entanto, o conteúdo mineralógico do Membro Assistência apresentou alterações, provavelmente causadas pela intrusão do diabásio (talco + pirofilita + calcita). O talco e a calcita foram formados devido à reação entre dolomita e quartzo, enquanto a pirofilita foi o produto da reação entre a caulinita e o quartzo. Palavras-chave: Bacia Sedimentar. Intrusões Ígneas. Metamorfização de sedimentos. Reações mineralógicas. XRD. SEM / EDS.
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Liang, Huan, Feng Zhou, Ze Ying Wu, Chun Jie Yan e Wen Jun Luo. "Surface Characteristics and Flotation Behaviour of Low-Grade Manganese Ore". Advanced Materials Research 962-965 (junho de 2014): 361–69. http://dx.doi.org/10.4028/www.scientific.net/amr.962-965.361.
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Evaluation possibility of low grade manganese mineral from Hunan by froth flotation technique was investigated. Manganese mineral sample was characterized with mineralogical analysis, XRD, and SEM studies for its mineral content and surface characteristics. XRD analysis showed that the gangue contents of manganese minerals are constituted mainly by dolomite as a carbonate mineral, quartz and feldspar. SEM indicated that existence of rhodochrosite, which mainly fills in the dolomite minerals. The influences of important factors on manganese mineral flotation are investigated. The size of grind, pulp pH, dosages of depressant and collector are essential to the effective recovery of rhodochrosite in manganese mineral flotation.
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Zvir, Yuliya, Carlos Pimentel e Carlos M. Pina. "The Effect of Stoichiometry, Mg-Ca Distribution, and Iron, Manganese, and Zinc Impurities on the Dolomite Order Degree: A Theoretical Study". Minerals 11, n.º 7 (29 de junho de 2021): 702. http://dx.doi.org/10.3390/min11070702.
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The determination of the degree of Mg-Ca order in the dolomite structure is crucial to better understand the process or processes leading to the formation of this mineral in nature. I01.5/I11.0 intensity ratios in the X-ray powder diffractograms are frequently measured to quantify dolomite cation order in dolomites. However, the intensity of diffraction peaks can be affected by factors other than the Mg-Ca distribution in the dolomite structure. The most relevant among these factors are (i) deviations from the ideal dolomite stoichiometry, and (ii) the partial substitution of Mg and Ca atoms by Fe, Mn, and Zn impurities. Using the VESTA software, we have constructed crystal structures and calculated I01.5/I11.0 ratios for dolomites with Mg:Ca ratios ranging from 0.5 to 1.5, and with Fe, Mn, and Zn contents up to 30%. Our results show that both deviations from dolomite ideal stoichiometry and the presence of impurities in its structure lead to a significant decrease in I01.5/I11.0 intensity ratios, an effect which must be considered when cation orders of natural dolomites from different origins are compared.
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Badouna, I., P. Koutsovitis, K. Laskaridis, M. Patronis e Ch Papatrechas. "AESTHETIC CHARACTERISTICS OF GREEK ORNAMENTAL STONES ASSOCIATED WITH MINERAL, GEOCHEMICAL AND STRUCTURAL PROPERTIES". Bulletin of the Geological Society of Greece 50, n.º 4 (28 de julho de 2017): 1771. http://dx.doi.org/10.12681/bgsg.14104.
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Commercial marble are almost ready-to-use materials with a high economic value for the building-construction industry. The most important ornamental stones in Greece include limestone and marble with notable qualitative features and are considered products of high commercial value. In this research, seventy-three carbonate samples (limestones, dolomites and marbles) from all over Greece have been studied to determine their macroscopic and petrographic features and to investigate their mineral chemistry and geochemistry. Their colors vary from whitish to gray due to their content of calcite and dolomite, black due to bitumens, yellow due to the presence of iron oxides and clay, red due to iron oxides and mixed phases of calcite- siderite, green-brownish due to the presence of iron oxides or muscovite and chlorite, giving schistosity to the rock. Scattered calcite and dolomite veins, as well as the occurrence of other minerals such as barite, epidote and magnetite, contribute to specific features, thus making their appearance unique. The particular characteristics of each stone depend highly upon the type of minerals present, their composition, grain size and extent of aggregation, their geochemistry and structure.
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Taylor, Kevin C., Hisham A. Nasr-El-Din e Sudhir Mehta. "Anomalous Acid Reaction Rates in Carbonate Reservoir Rocks". SPE Journal 11, n.º 04 (1 de dezembro de 2006): 488–96. http://dx.doi.org/10.2118/89417-pa.
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Summary It is generally assumed that the reaction of acid with limestone reservoir rock is much more rapid than acid reaction with dolomite reservoir rock. This work is the first to show this assumption to be false in some cases, because of mineral impurities commonly found in these rocks. Trace amounts of clay impurities in limestone reservoir rocks were found to reduce the acid dissolution rate by up to a factor of 25, to make the acid reactivity of these rocks similar to that of fully dolomitized rock. A rotating disk instrument was used to measure dissolution rates of reservoir rock from a deep, dolomitic gas reservoir in Saudi Arabia (275°F, 7,500 psi). More than 60 experiments were made at temperatures of 23 and 85°C and HCl concentration of 1.0 M (3.6 wt%). Eight distinctly different rock types that varied in composition from 0 to 100% dolomite were used in this study. In addition, the mineralogy of each rock disk was examined before and after each rotating disk experiment with an environmental scanning electron microscope (ESEM) using secondary and backscattered electron imaging and energy dispersive X-ray (EDS) spectroscopy. Acid reactivity was correlated with the detailed mineralogy of the reservoir rock. It was also shown that bulk anhydrite in the rock samples was converted to anhydrite fines by the acid at 85°C, a potential source of formation damage. Introduction A study of acid reaction rates and reaction coefficients of a dolomitic reservoir rock was recently reported by Taylor et al. (2004a). In that work, it was found that reaction rates depended on mineralogy and the presence of trace components such as clays. This paper examines in detail the relationship between acid reactivity and mineralogy of a deep, dolomitic gas reservoir rock. An accurate knowledge of acid reaction rates of deep gas reservoirs can contribute to the success of matrix and acid fracture treatments. Many studies of acid stimulation treatments of Formation K, a deep, dolomitic gas reservoir in Saudi Arabia, have been published (Nasr-El-Din et al. 2001, 2002a, 2002b; Bartko et al. 2003). It is generally assumed that the reaction of acid with limestone reservoir rock is much more rapid than acid reaction with dolomite reservoir rock during acidizing treatments. However, much of the reported data were obtained with pure limestones, dolomites, and marbles. These include calcite marble (CaCO3) (Lund et al. 1975; de Rozieres 1994; Frenier and Hill 2002), dolomite marble [CaMg(CO3)2] (Lund et al. 1973; Herman and White 1985), Indiana limestone (Mumallah 1991), St. Maximin and Lavoux limestones (Alkattan et al. 1998), Haute Vallée de l'Aude dolomite (Gautelier et al. 1999), Bellefonte dolomite (Herman and White 1985), San Andres dolomite (Anderson 1991), Kasota dolomite (Anderson 1991), and Khuff dolomite reservoir cores (Nasr-El-Din et al. 2002b). The effects of common acid additives on calcite and dolomite dissolution rates were reported in detail (Frenier and Hill 2002; Taylor et al. (2004b; Al-Mohammed et al. 2006). The effects of impurities such as clays on rock dissolution have not been reported.
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Goodwin-Bell, Jo-Anne S. "Delineation of isograds in siliceous dolomitic marbles along the Sharbot Lake – Frontenac terrane boundary of the Grenville Province, southeastern Ontario". Canadian Journal of Earth Sciences 45, n.º 6 (junho de 2008): 669–91. http://dx.doi.org/10.1139/e08-017.
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This study presents details of the mineralogy and petrology of siliceous, dolomitic marbles of the Sharbot Lake domain along the Frontenac terrane boundary in the Grenville Province of southeastern Ontario. The location of four mineral isograds in the marble and the related univariant reactions were identified in the Almonte – Carleton Place area. Delineation of the isograds is based on detailed mapping, petrographic analysis of coexisting mineral assemblages, and a polybaric T–XCO2 diagram calculated using thermobarometric data from associated gneissic rocks, where T is temperature and X is fluid composition. The T–X section is based on a field gradient of 32 °C/km. The isograds correspond to the first appearance of tremolite (5 dolomite + 8 quartz + H2O = tremolite + 3 calcite + 7 CO2), diopside (tremolite + 3 calcite + 2 quartz = 5 diopside + 3 CO2 + H2O), diopside + dolomite (tremolite + 3 calcite = dolomite + 4 diopside + H2O + CO2), and forsterite (diopside + 3 dolomite = 2 forsterite + 4 calcite + 5 CO2). Mineral assemblages above and below each isograd are described and relevant examples are shown. Results of this study are consistent with a mixed volatile fluid of a uniform composition during mid- to upper amphibolite-facies metamorphism.
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Yao, Jin, Ying Hou, Yu Lian Wang, Wen Xing Zhong e Wan Zhong Yin. "Research on the Floatability of Magnesite and its Gangue Minerals with Sodium Oleate and Lauryl Amine as Collectors". Advanced Materials Research 798-799 (setembro de 2013): 328–32. http://dx.doi.org/10.4028/www.scientific.net/amr.798-799.328.
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In this study, the single mineral flotation experiments of magnesite and its associated minerals including dolomite, serpentine, talc and quartz were conducted, and the influences of the dosage of collectors such as sodium oleate and lauryl amine, pH value and the influences of regulars such as sodium hexametaphosphate and sodium silicate on those minerals were researched. According to the results, a process to reduce the content of gangue minerals was proposed, which at first use lauryl amine as a collector to remove most talc and quartz and part of the dolomite and serpentine, and then use sodium oleate as a collector to separate magnesite from dolomite and serpentine. This is a theoretical reference for the beneficiation of magnesite.
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Mao, Song, e Qin Zhang. "Mineralogical Characteristics of Phosphate Tailings for Comprehensive Utilization". Advances in Civil Engineering 2021 (31 de março de 2021): 1–13. http://dx.doi.org/10.1155/2021/5529021.
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The mineralogical characteristics of a phosphate tailing were studied, and the occurrence state, mineral types, and embedded characteristics of phosphorus in the phosphate tailings were ascertained. The results show that the main minerals in the phosphate tailings are collophane. The main gangue minerals are quartz, dolomite, calcite, a small amount of potassium feldspar, plagioclase, chlorite, etc. Monazite was found in phosphate tailings. In addition, the coarse grain size of quartz and feldspar and fine embedded particle size of calcite and dolomite are also the main factors affecting the mineral processing of phosphate tailings. According to the analysis of mineralogical characteristics, the physical and chemical properties of phosphate tailings provided the basis for comprehensive utilization of phosphorus resources.
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Shen, Zhi Hui, Xiao Tai He, Qin Zhang e Xiao Fen Huang. "The Solution Chemistry of the Effect of the Dissolved Ions on the Flotation Process in Collophane-Dolomite System". Advanced Materials Research 881-883 (janeiro de 2014): 1674–78. http://dx.doi.org/10.4028/www.scientific.net/amr.881-883.1674.
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The grain size of collophane and dolomite in phosphate ore is tiny, and the interaction of dissolved ions in solution and the re-adsorption of dissolved ions on mineral surface have a great influence on the flotation process. Because carbonate and phosphate have the similar surface properties, which have the larger concentration of the dissolved component in the pulp, and the dissolution, adsorption and equilibrium of mineral ions have a larger effect on the flotation process. In this experiment, cellophane-dolomite system was used as the research object, the solution chemistry of the effect of mineral dissolved ions on the flotation process was discussed. The test results show that under the open system, the pH of pulp increases and maintains at between 9.64~9.73 in dolomite natural dissolution process. While in collophane natural dissolution process, the pH increases and maintains at between 8.94~9.06, and the buffer capacity of collophane is weaker than dolomite. In the alkaline range, as the major dissolved ions of mineral coexistence system, CO32-and PO43-affect the conversion and separation between minerals.
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Zeng, Lianbo, Zhiguo Shu, Wenya Lyu, Mingjing Zhang, Hanyong Bao, Shaoqun Dong, Shuangquan Chen e Xiang Xu. "Lamellation Fractures in the Paleogene Continental Shale Oil Reservoirs in the Qianjiang Depression, Jianghan Basin, China". Geofluids 2021 (5 de maio de 2021): 1–10. http://dx.doi.org/10.1155/2021/6653299.
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Based on the data of cores, thin sections, well logs, and test experiments, the characteristics and main controlling factors of lamellation fractures in continental shales of the third and fourth members of the Paleogene Qianjiang Formation in the Qianjiang Depression, Jianghan Basin, are studied. Lamellation fractures mainly develop along laminas in shales. They have various morphological characteristics such as straightness, bending, discontinuity, bifurcation, pinching out, and merging. Lamellation fractures with high density show poor horizontal continuity and connectivity characteristics. The average linear density of the lamellation fractures is mainly between 20 m-1 and 110 m-1, and the aperture is usually less than 160 μm. The density of lamellation fractures is related to their apertures. The smaller the apertures of lamellation fractures are, the higher the density is. The development degree of lamellation fractures is mainly controlled by mineral composition, type, thickness, density of lamination, contents of organic matter and pyrite, lithofacies, structural position, etc. Lamellation fractures develop well, especially under the conditions of medium dolomite content, large lamination density, small lamination thickness, and high total organic carbon (TOC) and pyrite contents. The influences of lithofacies on the lamellation fractures are complex. The lamellation fractures are most developed in carbonaceous layered limestone dolomite and carbonaceous layered dolomite mudstone, followed by stromatolite dolomite filled with carbonaceous pyroxene. The fractures in the massive argillaceous dolomites and carbonaceous massive mudstones are poorly developed. No fractures can be found in the carbonaceous dolomitic, argillaceous glauberites or salt rocks with high glauberite content. Structure is also an important factor controlling lamination fractures. Tectonic uplifts are beneficial to the expansion and extension of lamellation fractures, which increases fracture density. Therefore, when other influence factors are similar, lamellation fractures develop better in the high part of the structure than in the low part.
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Süzen, M. L., e A. G. Türkmenoğlu. "Lacustrine mineral facies and implications for estimation of palaeoenvironmental parameters: Neogene intervolcanic Pelitçik Basin (Galatean Volcanic Province), Turkey". Clay Minerals 35, n.º 3 (junho de 2000): 461–75. http://dx.doi.org/10.1180/000985500546882.
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AbstractThe mineralogy of the Neogene lacustrine facies of Pelitçik basin was investigated for the purpose of deriving the palaeoenvironmental parameters of this intervolcanic basin. The laboratory studies indicate that dolomite and K-feldspar are the major non-clay minerals in the study area, where plagioclase, analcime, fibrous zeolite and quartz are the minor constituents. Dolomites are found to be non-stoichiometric in chemistry. The clay fraction of the lacustrine facies is composed mainly of dioctahedral smectites. The smectites are rich in Al-Fe indicating a detrital origin. Illite comprises a minor contribution to the clay fraction, where chlorite and kaolinite are found in trace amounts. Based on dolomite stoichiometry and the mineral paragenesis found in the Pelitçik basin, the depositional conditions are suggested to have been a shallow, quiet, perennial lacustrine environment with fresh to slightly saline and slightly alkaline water chemistry. In addition, based on geological and mineralogical constraints, it is suggested that the water chemistry fluctuated during the deposition of the Pazar formation and the lake began its evolution with a hydrologically closed system and completed its evolution with a hydrologically open system.
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He, Xiao Tai, Qin Zhang e Shu Hao Qin. "Floating Separation between Collophanite and Dolomite Affected by Inorganic Interaction". Advanced Materials Research 881-883 (janeiro de 2014): 1665–69. http://dx.doi.org/10.4028/www.scientific.net/amr.881-883.1665.
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According to the type of Guizhou marine sedimentary phosphorus ore, the main reason of refractory is the similar surface properties of collophane and dolomite.In addition,the interaction of dissolved components of mineral and external ion leads the new eguilibrium system in aqueous solution,which further affects the selective adsorption of the agent in mineral surface.Selecting collophanite-dolomite system as the research object, this article studies the effect of the interaction of some inorganic anions on the floatability difference of the two minerals in the flotation system. The effect of the interaction on the electric properties of the mineral surface and adsorption characteristics were also examined with the purpose to find out the interaction mechanism.It hopes to provide theoretical basis for practical mineral selection. The research findings shows that in the range of pH 3 to 5, the interaction of PO43- and SO42- has a better effect of the separation between collophanite and dolomite.The interactions of SiO32- and CO32- makes the floatability difference of collophanite and dolomite closer when the pH is greater than 9.25, and simultaneously shows some negative effects on the flotation separation of the two minerals.
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Kirilovica, Inta, Linda Krage, Inta Vitina e Silvija Igaune-Blumberga. "Chemical and Physical Processes in the Synthesis of Romancement from Clay and Dolomite". Key Engineering Materials 604 (março de 2014): 102–5. http://dx.doi.org/10.4028/www.scientific.net/kem.604.102.
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This work deals with the synthesis of binder, similar to historic dolomitic romancement, from mixture of clay and dolomite instead of traditionally used marlstone, thus widening the range of raw materials. In the territory of Latvia dolomitic romancement was widely known and applied in the construction of buildings since late 19th till the middle of 20th century. Nowadays the local dolomitic marlstone is not sufficiently available. As the scientists have faced the problem adjusting compatible material for restoration of historical buildings of given time period, research is done with the aim to investigate the synthesis of romancement type binder from widespread local mineral raw materials for the restoration purposes. In given paper the chemical and physical processes in the synthesis and also obtained properties are discussed.
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Chen, Yong, Yongsheng Song, Wenjuan Li e Liulu Cai. "Mineralogical Characteristics of a Micro-Fine and Low Grade Refractory Gold Ore". MATEC Web of Conferences 142 (2018): 02011. http://dx.doi.org/10.1051/matecconf/201814202011.
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Detailed characterization of a micro-fine, low-grade refractory gold ore from a beneficiation plant in Yunnan Province, China, was investigated. Different analytical techniques, such as videlicet size analysis, scanning electron microscopy, and mineral analysis by a Mineral Liberation Analyser, were used for mineralogical characterization of the ore. The results show that the most valuable metal is gold. Grain size of pyrites and arsenian pyrites, which are main gold carrying minerals, are mostly 1 ~ 30 μ m. The gangue mineral is composed of quartz, mica, dolomite and feldspar, while the content of easy-to-float and clay gangue minerals is up to 33%.
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Stanienda, Katarzyna. "Possibility of Huntite presence in the Triassic limestones of Opole Silesia". Gospodarka Surowcami Mineralnymi - Mineral Resources Management 29, n.º 3 (1 de setembro de 2013): 79–98. http://dx.doi.org/10.2478/gospo-2013-0036.
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Streszczenie W niniejszym artykule przedstawiono wyniki badań próbek skał węglanowych pobranych z utworów triasowych, w obszarze Śląska Opolskiego. Przedmiotem badań była identyfikacja huntytu - fazy węglanowej, o podwyższonej, w porównaniu z kalcytem magnezowym i dolomitem, zawartości magnezu. Huntyt powstaje zwykle wskutek procesów hydrotermalnych, wietrzenia dolomitu lub w wyniku przeobrażenia, w warunkach wysokich temperatur, kalcytu magnezowego. W skałach osadowych występuje w utworach strefy wadycznej (aeracji). W celu stwierdzenia obecności huntytu, wybrane próbki skał poddano analizom FTIR, rentgenowskiej oraz badaniom w mikroobszarach. Minerał ten zidentyfikowano w skałach wapienia muszlowego, w wapieniach warstw gogolińskich, górażdżańskich, dziewkowickich i karchowickich. W przypadku analizy FTIR, o obecności huntytu świadczy występowanie w widmach absorpcyjnych, w próbkach 1 i 4 pasma 1555 cm-1, w próbce 3 - pasma 1562 cm-1, a w próbce 2 - pasma 1572 cm-1. W dyfra kto gra mach rentgenowskich wszystkich badanych próbek, fazę węglanową uznaną za huntyt zidentyfikowano na podstawie linii dy|frakcyjnej, o najwyższej intensywności i wartości dhkl - 2,83 A. Badania w mikroobszarach pozwoliły na zidentyfikowanie huntytu w wapieniach dziewkowickich oraz karchowickich. Oznaczone w punktach mikroobszarów badanych próbek, zawartości magnezu, wahają się od 14,01% Mg (23,23% MgO) do 16,18% Mg (26,83% MgO). Wartości te przekraczają znacznie wartość stechiometryczną, typową dla dolomitu (21,86% MgO, 13,12% Mg). Oznaczona w mikroobszarach ilość magnezu w huntycie jest jednak niższa od wartości stechiometrycznej dla tej fazy węglanowej, która wynosi 20,65% Mg (34,25% MgO). Prawdopodobnie, wskutek procesów diagenezy (de- dolomityzacja ?) mogło dojść do usunięcia części jonów magnezu z kryształów huntytu. Analizując możliwości tworzenia się huntytu, fazy węglanowej o podwyższonej zawartości magnezu, w więk- szym stopniu niż Mg-kalcyt czy dolomit, można podejrzewać, że minerał ten powstał w obszarach zbiornika germańskiego, w których procesy diagenezy zachodziły przy udziale wód strefy wadycznej.
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Chung, Baru, Jaehyung Yu, Lei Wang, Nam Hoon Kim, Bum Han Lee, Sangmo Koh e Sangin Lee. "Detection of Magnesite and Associated Gangue Minerals using Hyperspectral Remote Sensing—A Laboratory Approach". Remote Sensing 12, n.º 8 (22 de abril de 2020): 1325. http://dx.doi.org/10.3390/rs12081325.
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This study introduced a detection method for magnesite and associated gangue minerals, including dolomite, calcite, and talc, based on mineralogical, chemical, and hyperspectral analyses using hand samples from thirteen different source locations and Specim hyperspectral short wave infrared (SWIR) hyperspectral images. Band ratio methods and logistic regression models were developed based on the spectral bands selected by the random forest algorithm. The mineralogical analysis revealed the heterogeneity of mineral composition for naturally occurring samples, showing various carbonate and silicate minerals as accessory minerals. The Mg and Ca composition of magnesite and dolomite varied significantly, inferring the mixture of minerals. The spectral characteristics of magnesite and associated gangue minerals showed major absorption features of the target minerals mixed with the absorption features of accessory carbonate minerals and talc affected by mineral composition. The spectral characteristics of magnesite and dolomite showed a systematic shift of the Mg-OH absorption features toward a shorter wavelength with an increased Mg content. The spectral bands identified by the random forest algorithm for detecting magnesite and gangue minerals were mainly associated with spectral features manifested by Mg-OH, CO3, and OH. A two-step band ratio classification method achieved an overall accuracy of 92% and 55.2%. The classification models developed by logistic regression models showed a significantly higher accuracy of 98~99.9% for training samples and 82–99.8% for validation samples. Because the samples were collected from heterogeneous sites all over the world, we believe that the results and the approach to band selection and logistic regression developed in this study can be generalized to other case studies of magnesite exploration.
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Lugra, I. Wayan. "HEAVY MINERAL DISTRIBUTION PATTERNS AND CHARACTERISTICS OF SEA FLOOR SURFICIAL SEDIMENT AT EAST BALI WATERS, BALI PROVINCE". BULLETIN OF THE MARINE GEOLOGY 26, n.º 2 (15 de fevereiro de 2016): 105. http://dx.doi.org/10.32693/bomg.26.2.2011.38.
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Analyses result of the heavy minerals that was took from beach sediments and sea floor surficial sediments was founded ten heavy minerals namely hematite, magnetite, limonite and rutile from oxide and hydroxide group, pyroxene, amphibol and zircon from silicate group, biotit from mica group, barite from sulfide group and dolomite from carbonate group. From 10 minerals identified, only magnetit distributes in the whole area, with the highest percentage of 34,15% in the sea and 35,14 % on beaches. Other heavy minerals distribute locally with the percentage of less than 0,01 %. Grain size analyses result of sea floor surficial sediment had identified six units sediment such as sand, sand with few gravel, sandy gravel, gravely sand, gravel and reef. Distribution area of the six units sediment as follows sand and sandy gravel are occupied 25 % respectively of the study area, reef 20%, sand 15 %, gravel 10 % and gravely sand occupied 5%. The best sediment for making art goods is sand sizes which is rich of heavy minerals such as magnetite, hematitre, limonite, zircon, pyroxene and amphibol. If will be exploited of the sand sediment on beach or sea floor surficial sediment, should be considering of the environment sustainable.
Keyword: grain size analyses, heavy mineral, seafloor surficial sediment, besach sediment, Karang Asem
Hasil analisis mineral berat dari sedimen pantai dan permukaan dasar laut dijumpai sepuluh jenis mineral berat yaitu magnetit, hematit, limonit, rutil dari kelompok oksida & hidroksida, piroksen, ampibol, sirkon dari kelompok silikat, biotit dari kelompok mika, barit dari kelompok sulfida dan dolomit dari kelompok karbonat. Dari sepuluh jenis mineral berat yang teridentifikasi hanya magnetit yang sebarannya merata di seluruh daerah penyelidikan baik di laut maupun di pantai dengan persentase tertinggi 34,15 % di laut dan 35,14% di pantai, sedangkan sembilan mineral lainnya sebarannya tidak merata atau setempat-setempat dengan persentase umumnya di bawah 0,01 %. Hasil analisis besar butir sedimen permukaan dasar laut dapat di bedakan menjadi 6 satuan yaitu pasir, pasir sedikit krikilan, pasir krikilan, krikil pasiran, krikil dan terumbu karang. Luas sebaran ke enam jenis sedimen tersebut terhadap luas daerah penelitian adalah pasir sedikit krikilan menempati 25%, pasir krikilan 25%, terumbu karang 20%, pasir 15%, krikil 10% dan menempati pasir krikilan 5%. Jenis sedimen yang baik untuk pembuatan benda seni adalah sedimen berukuran pasir dengan kandungan mineral berat yang tinggi seperti magnetit, hematit, limonit, sirkon, piroksen, dan ampibol. Bila akan dilakukan eksploitasi terhadap sedimen jenis pasir baik di laut maupun di pantai, harus memperhatikan kelestarian lingkungan.
Kata kunci: analisis besar butir, mineral berat, sedimen permukaan dasar laut, sedimen pantai, Karang Asem
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Liu, Pengfei, Yingjun Zhao, Tianxu Guo e Hongda Zhang. "Hyperspectral analysis of shale gas drilling in southern Huangling anticline". E3S Web of Conferences 261 (2021): 01048. http://dx.doi.org/10.1051/e3sconf/202126101048.
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In this paper, the visible near infrared, short wave red, and thermal infrared spectral data and high-definition core images of three wells in Huangling anticline in Western Hubei are obtained by hylogger. Through comprehensive analysis, it can be seen that the thickness of Niutitang Formation is decreasing from west to East, However, the thickness of Doushantuo Formation is basically the same, ranging from 210m to 220m. Quartz, clay minerals, carbonate and limonite are the main minerals in Niutitang formation, while in Doushantuo Formation dolomite is the main mineral. Dolomite fracture is developed in this area, which is a favorable area for shale gas development.
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Bozkaya, Ömer, Hüseyin Yalçin e Hüseyin Kozlu. "Clay mineralogy of the Paleozoic-Lower Mesozoic sedimentary sequence from the northern part of the Arabian Platform, Hazro (Diyarbakır, Southeast Anatolia)". Geologica Carpathica 62, n.º 6 (1 de dezembro de 2011): 489–500. http://dx.doi.org/10.2478/v10096-011-0035-6.
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Clay mineralogy of the Paleozoic-Lower Mesozoic sedimentary sequence from the northern part of the Arabian Platform, Hazro (Diyarbakır, Southeast Anatolia)The Paleozoic-Lower Mesozoic units in the Diyarbakır-Hazro region consist of sandstone (subarkose, quartz arenite), mudstone, shale, coal, marl, dolomitic marl, limestone (biomicrite, lithobiosparite, biosparite with lithoclast, dololithobiosparite, dolomitic cherty sparite) and dolomite (dolosparite, dolosparite with lithoclast, biodolosparite with glauconite). These units exhibit no slaty cleavage although they are oriented parallel to bedding planes. The sedimentary rocks contain mainly calcite, dolomite, quartz, feldspar, goethite and phyllosilicates (kaolinite, illite-smectite (I-S), illite and glauconite) associated with small amounts of gypsum, jarosite, hematite and gibbsite. The amounts of quartz and feldspar in the Silurian-Devonian units and of dolomite in the Permian-Triassic units increase. Kaolinite is more commonly observed in the Silurian-Devonian and Permian units, whereas illite and I-S are found mostly in the Middle Devonian and Triassic units. Vertical distributions of clay minerals depend on lithological differences rather than diagenetic/metamorphic grade. Authigenetic kaolinites as pseudo-hexagonal bouquets and glauconite and I-S as fine-grained flakes or filaments are more abundantly present in the levels of clastic and carbonate rocks. Illite quantities in R3 and R1 I-S vary between 80 and 95 %. 2M1+1Mdillites/I-S are characterized by moderatebcell values (9.005-9.040, mean 9.020 Å), whereas glauconites have higher values in the range of 9.054-9.072, mean 9.066 Å. KI values of illites (0.72-1.56, mean 1.03 Δ2θ°) show no an important vertical difference. Inorganic (mineral assemblages, KI, polytype) and organic maturation (vitrinite reflection) parameters in the Paleozoic-Triassic units agree with each others in majority that show high-grade diagenesis and catagenesis (light petroleum-wet gas hydrocarbon zone), respectively. The Paleozoic-Triassic sequence in this region was deposited in the environment of a passive continental margin and entirely resembles the Eastern Taurus Para-Autochthon Unit (Geyikdağı Unit) in respect of lithology and diagenetic grade.
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Susilawati, Rita. "MINERAL MATTER IN COAL". Buletin Sumber Daya Geologi 10, n.º 1 (8 de maio de 2015): 14–27. http://dx.doi.org/10.47599/bsdg.v10i1.134.
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The term “mineral matter” in coal is defined as all inorganic, non-combustible material that is in or associated with coal which include discrete crystalline mineral particles, dissolved ions and other inorganic components in the pore water or surface water of the coal, and inorganic elements combined within the organic compounds of the coal macerals. The minerals existing in coal are aresult of processes that occur throughout the entire history of coal formation. Its distribution is influenced by biological, hydrological and geochemical factors. Quartz and the clay minerals are the most widespread and abundant mineral found in coal. Another common minerals are feldspars and carbonate in the form of siderite, calcite and dolomite and sulfide minerals such as pyrite. Coal mineral matter analysis and characterization are useful for various reasons, particularly to take as much as benefit from coal utilization and to avoid any negative influence of coal inorganic components to the environment.
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Bai, Junzhi, Jizhen Wang, Wanzhong Yin e Xiangxiang Chen. "Influence of Sodium Phosphate Salts with Different Chain Length on the Flotation Behavior of Magnesite and Dolomite". Minerals 10, n.º 11 (19 de novembro de 2020): 1031. http://dx.doi.org/10.3390/min10111031.
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This paper analyzes the influence of sodium phosphate salts with different chain lengths as depressants on the flotation behavior of magnesite and dolomite through single mineral flotation test, contact angle test, and theoretical analysis. Flotation tests show that depressants should be added for the flotation separation of magnesite and dolomite. The inhibition of sodium phosphate salts on dolomite is significantly stronger than magnesite, and the flotation difference of minerals is affected by the chain length of phosphate depressants. The order of flotation separation enhancement of different sodium phosphate depressants is sodium hexametaphosphate ≈ sodium tetrapolyphosphate > sodium tripolyphosphate > sodium pyrophosphate. This result could also be supported by the contact angle measurement.
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Garcia, Encarnación, Pura Alfonso e Esperança Tauler. "Mineralogical Characterization of Dolomitic Aggregate Concrete: The Camarasa Dam (Catalonia, Spain)". Minerals 10, n.º 2 (29 de janeiro de 2020): 117. http://dx.doi.org/10.3390/min10020117.
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The Camarasa Dam was built in 1920 using dolomitic aggregate and Portland cement with two different compositions: type A (dolomite and Portland cement) and type B (dolomite and sand-cement). The sand cement was a finely powdered mixture of dolomite particles and clinker of Portland cement. The mineralogy of concrete was studied by optical microscopy, scanning electron microscopy, and x-ray powder diffraction. Reaction of dedolomitization occurred in the two types of concrete of the Camarasa Dam, as demonstrated by the occurrence of calcite, brucite, and/or absence of portlandite. In the type A concrete, calcite, brucite, and a serpentine-group mineral precipitated as a rim around the dolomite grains and in the paste. The rims, a product of the dedolomitization reaction, protected the surface of dolomite from the dissolution process. In type B concrete, in addition to dolomite and calcite, quartz and K-feldspar were present. Brucite occurred in lower amounts than in the type A concrete as fibrous crystals randomly distributed in the sand-cement paste. Although brucite content was higher in the type A concrete, type B showed more signs of loss of durability. This can be attributed to the further development of the alkali-silica reaction in this concrete type.
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Yalcin, M. G., M. Setti, F. Karakaya, E. Sacchi e N. Ilbeyli. "Geochemical and mineralogical characteristics of beach sediments along the coast between Alanya and Silifke (southern Turkey)". Clay Minerals 50, n.º 2 (junho de 2015): 233–48. http://dx.doi.org/10.1180/claymin.2015.050.2.07.
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AbstractThe aim of this work was to determine the distribution of trace metals in the coastal sediments from the area between Silifke and Alanya (Turkey) and to investigate the sources of these elements, based on their mineralogical, petrographical and geochemical characteristics. Forty three samples were analysed for the determination of their water content, grain-size distribution, petrographical features and their chemical and mineralogical compositions. The samples had low water content, in agreement with the large sand grain size.The mineralogical composition reflects the complex geological setting of the area. The most abundant mineral phases are represented by calcite and dolomite, followed by quartz and mica. Chlorite, feldspar and other carbonates are present in lesser amounts, while kaolinite was detected in one sample only. All samples contain hematite, chromite, magnetite and goethite and one sample contained pyrite. Samples with high concentrations of trace metals, contained fragments of metamorphic rocks with pyroxene, amphibole, quartz and feldspar, whereas carbonates and opaque minerals were subordinate. Compared to literature data, the average concentrations of several elements and trace metals were great enough to be considered as possibly toxic, exceeding the Turkish higher acceptable limits. Geochemical data were treated statistically using Principal Component Analysis (PCA) to obtain evidence of their distribution and to identify any correlations.Based on the distribution of mineral phases, the area investigated was divided into different provinces, each characterized by the abundance of one, or more, tracer minerals. In the westernmost areas, between Alanya and Demirtas, the sediments indicate a provenance from dolomites or marbles. In the area between Demirtas and Gazipasa the provenance was from quartzites, clastic and metamorphic rocks and in the sector between Guney and Anamur, the sediments were derived mostly from low-grade metamorphic rocks, in particular metaschists and metabasites. The sediments in the area between Anamur and Ovacik, display variable source rocks and those between Ovacik and Silifke, were derived from limestones and, subordinately, clastic rocks.The trace-metal concentrations in beach sands appear to be related to the abundance of silicate minerals derived from weathering of the metamorphic-rock outcrops in the inland mountainous regions. In contrast, the trace-metal contents of the limestone- and dolomite-bearing beach sands were small.
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Rajan, S., e J. K. Raghavan. "Coal Mineral Matter Transformation During Combustion and Its Effects on Gas Turbine Blade Deposition and Erosion". Journal of Engineering for Gas Turbines and Power 115, n.º 3 (1 de julho de 1993): 634–40. http://dx.doi.org/10.1115/1.2906753.
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The reaction pathways along which mineral matter is transformed during pulverized coal combustion and the corresponding characteristics of the ash formed are especially important from the standpoint of coal-fired gas turbine operation. Using a novel FT-IR technique and EDX analysis, these mineral matter transformations are investigated when coal is burned in a pulverized coal-dust burner. The mineral transformations of quartz, gypsum, calcite, dolomite, pyrite, and those of the aluminosilicate minerals, kaolinite and montmorillonite, have been evaluated. Discussion of the results focuses on the effect of these mineral transformations on the deposition and erosive characteristics of the resulting combustion-generated ash.
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Yao, J., H. Han, Y. Hou, E. Gong e W. Yin. "A Method of Calculating the Interaction Energy between Particles in Minerals Flotation". Mathematical Problems in Engineering 2016 (2016): 1–13. http://dx.doi.org/10.1155/2016/8430745.
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Extended-DLVO (Derjaguin-Landau-Verwey-Overbeek) theory is applied to calculating the interaction energy between particles in flotation process in the paper. This study investigates and compares the floatability of magnesite, dolomite, serpentine, and quartz in single mineral flotation and artificial mixture flotation with DDA as collector. The results showed that when the pH, dissolved ions, and competitive adsorption had a minor influence on their floatability, fine magnesite and dolomite largely decreased the recovery of quartz. SEM analysis on the flotation products demonstrated severe masking of fine particles on the surface of quartz. The Extended-DLVO theory was applied to calculate the interaction energy between the minerals, and the results showed that the interaction forces between magnesite and quartz, serpentine and quartz, and dolomite and quartz were attractive; therefore, fine magnesite, serpentine, and dolomite particles are easily masked on the surface of quartz. The calculation results agree with the experiment results and explain the mechanism of particles interaction and the reasons for the inconsistency in single mineral flotation and actual ore flotation. The particles interaction behavior is important in flotation process, and the interaction energy calculation is helpful for evaluating this behavior.
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Neaman, Alexander, Arieh Singer e Karl Stahr. "Clay mineralogy as affecting disaggregation in some palygorskite containing soils of the Jordan and Bet-She'an Valleys". Soil Research 37, n.º 5 (1999): 913. http://dx.doi.org/10.1071/sr98118.
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The influence of clay mineralogy on disaggregation in some palygorskite-containing soils of the Jordan and Bet-She'an Valleys was examined. The disaggregation potential of different minerals in the soil clay fraction was investigated by establishing differences in the mineral suite between the original and disaggregated clay fractions. By shaking the soil with distilled water, calcite, dolomite, feldspar, and palygorskite were disaggregated preferentially. The pattern for quartz was inconsistent. Among phyllosilicates, palygorskite was the most strongly, disaggregated, while smectite was the least disaggregated mineral. The disaggregation potential of kaolinite was of intermediate value. By shaking the soil with 0 ⋅ 01 N NaCl, calcite and dolomite were released preferentially, and were the dominant minerals in the disaggregated clay fraction. Scanning electron microscopy observations indicate that palygorskite fibres do not associate into aggregates in soils and suspensions, even when saturated with calcium ions. The present findings are relevant for soils with low exchangeable sodium percentage. These soils can be expected under rain-fed agriculture or irrigation with high quality water which has a low sodium adsorption ratio.
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Ryan, Brooks H., Stephen E. Kaczmarek e John M. Rivers. "Multi-episodic recrystallization and isotopic resetting of early-diagenetic dolomites in near-surface settings". Journal of Sedimentary Research 91, n.º 1 (31 de janeiro de 2021): 146–66. http://dx.doi.org/10.2110/jsr.2020.056.
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ABSTRACT The lower Eocene Rus Formation in Qatar reflects carbonate deposition in a semirestricted to fully restricted marine setting on a shallow ramp. Petrographic, mineralogical, and geochemical evidence from three research cores show early diagenesis has extensively altered nearly every petrological attribute of these rocks despite not having been deeply buried. In southern Qatar, the lower Rus (Traina Mbr.) consists of fabric-retentive dolomite intervals that preserve mudstone, wackestone, and packstone textures that are interbedded with depositional gypsum beds. In northern Qatar, the same member is dominated by fabric-destructive planar-e dolomite, and evaporites are absent. In both northern and southern Qatar, the upper Rus (Al Khor Mbr.) is composed of fabric-retentive dolomite intervals as well as limestone intervals rich with Microcodium textures that display evidence of dedolomitization. Geochemical analysis reveals that the limestones have an average δ18Ocal of –10.73‰ VPDB and δ13Ccal of –7.84‰ VPDB, whereas average dolomite δ18Odol is significantly higher (–1.06‰ VPDB) but δ13Cdol values (–3.04‰ VPDB; range –10 to 0‰) overlap with δ13Ccal values. Additionally, δ13Cdol trends toward normal marine values with depth away from the calcite–dolomite contact in all three cores. Petrographic observations demonstrate that dolomite crystals are commonly included in calcite and partially to completely replaced by calcite in these intervals and suggests that dolomite formed before calcite in the Microcodium-bearing intervals. Furthermore, the dolomites are commonly cemented by gypsum in the Traina Mbr. in southern Qatar, suggesting that dolomitization may have also occurred before, or concurrent with, bedded gypsum formation and indicates that dolomitization occurred early. Early dolomites were subsequently replaced by Microcodium-bearing limestones at and immediately below paleo-exposure surfaces, and at greater depths recrystallized in mixed marine–meteoric fluids, producing a negative δ13Cdol signature that trends toward more positive values away from the limestone–dolomite contact. Lastly, the dolomites underwent another phase of recrystallization in either marine-dominated fluids or possibly a well-mixed aquifer setting, resulting in a near-0‰ δ18Odol signature but retaining the negative δ13C signature. These findings thus have implications for reconstructing the diagenetic history of carbonate rocks, as they suggest that early diagenesis of carbonates can be extremely complex, resulting in multiple stages of mineral replacement and isotopic exchange in meteoric and shallow marine fluids before significant burial. Furthermore, this study shows that dolomitization of a limestone does not necessarily prevent additional early diagenesis and multiple recrystallization events. Lastly, it emphasizes the importance of incorporating petrographic observations with geochemical data when interpreting the diagenetic history of carbonate rocks.
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Herman, Richard G., Charles E. Bogdan, Andre J. Sommer e Dale R. Simpson. "Discrimination among Carbonate Minerals by Raman Spectroscopy Using the Laser Microprobe". Applied Spectroscopy 41, n.º 3 (março de 1987): 437–40. http://dx.doi.org/10.1366/0003702874448841.
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Raman spectroscopy has been used to distinguish the individual carbonate minerals belonging to the calcite, dolomite, and aragonite structural groups. With the use of the in situ laser microprobe technique, it is demonstrated that particle-size effects do not hinder the mineral identification and that high precision in line position is achieved. Spectra can be obtained from samples in any form and provide rapid, nondestructive analyses on a microscopic scale of the hard-to-discriminate carbonate minerals.
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Fu, Yan Xiong, Bao Liang Ge, Qing Li e Jing Lu Zhang. "Process Mineralogy Study on a Sandstone Copper Ore". Advanced Materials Research 881-883 (janeiro de 2014): 1603–6. http://dx.doi.org/10.4028/www.scientific.net/amr.881-883.1603.
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In this thesis the object of study is a low grade sandstone copper with complex composition. Through the process mineralogy research on a sandstone copper ore,the result showed that the primary sulfide copper minerals are tetrahedrite and chalcopyrite; secondary sulfide copper minerals are bornite, chalcocite and azurite; the main oxide copper mineral is malachite; the main gangue mineral is quartz. The grade of copper is 0.77% and the oxidation rate is 45.45% in the run of mine, it is an oxide copper ore with not thoroughly oxidation. There is a part of disseminated particle size of copper minerals is relatively fine. Mainly sulfide copper minerals are paragenesis with dolomite and pyrite; oxide copper minerals are often blended with limonite. So the key of obtaining the good flotation index is selecting reasonably grinding fineness and making the part of fine-grained disseminated copper full liberation.
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Hu, Le, Yike Li, Maoshan Chuan, Ruiping Li, Changhui Ke e Zhongjian Wu. "Post-Magmatic Fluids Dominate the Mineralization of Dolomite Carbonatitic Dykes Next to the Giant Bayan Obo REE Deposit, Northern China". Minerals 10, n.º 12 (12 de dezembro de 2020): 1117. http://dx.doi.org/10.3390/min10121117.
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The Bayan Obo rare earth element (REE) deposit in Inner Mongolia, northern China, is the largest REE deposit in the world, whose mineralization process remains controversial. There are dozens of carbonatite dykes that are tightly related to the deposit. Here we report the petrological and mineralogical characteristics of a typical dolomite carbonatite dyke near the deposit. The dolomite within the dyke experienced intense post-emplacement fluids metasomatism as evidenced by the widespread hydrothermal REE-bearing minerals occurring along the carbonate mineral grains. REE contents of bulk rocks and constituent dolomite minerals (>90 vol.%) are 1407–4184 ppm and 63–152 ppm, respectively, indicating that dolomite is not the dominant mineral controlling the REE budgets of the dyke. There are three types of apatite in the dyke: Type 1 apatite is the primary apatite and contains REE2O3 at 2.35–4.20 wt.% and SrO at 1.75–2.19 wt.%; Type 2 and Type 3 apatites are the products of replacement of primary apatite. The REE2O3 (6.10–8.21 wt.%) and SrO (2.83–3.63 wt.%) contents of Type 2 apatite are significantly elevated for overprinting of REE and Sr-rich fluids derived from the carbonatite. Conversely, Type 3 apatite has decreased REE2O3 (1.17–2.35 wt.%) and SrO (1.51–1.99 wt.%) contents, resulting from infiltration of fluids with low REE and Na concentrations. Our results on the dyke suggest that post-magmatic fluids expelled from the carbonatitic melts dominated the REE mineralization of the Bayan Obo deposit, and a significant fluid disturbance occurred but probably provided no extra REEs to the deposit.
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Elisha, Bar, Perach Nuriel, Andrew Kylander-Clark e Ram Weinberger. "Towards in situ U–Pb dating of dolomite". Geochronology 3, n.º 1 (26 de maio de 2021): 337–49. http://dx.doi.org/10.5194/gchron-3-337-2021.
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Abstract. Recent U–Pb dating by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) has demonstrated that reasonable precision (3 %–10 %, 2σ) can be achieved for high-resolution dating of texturally distinct calcite phases. Absolute dating of dolomite, for which biostratigraphy and traditional dating techniques are very limited, remains challenging, although it may resolve many fundamental questions related to the timing of mineral-rock formation by syngenetic, diagenesis, hydrothermal, and epigenetic processes. In this study we explore the possibility of dating dolomitic rocks via recent LA-ICP-MS dating techniques developed for calcite. The in situ U–Pb dating was tested on a range of dolomitic rocks of various origins from the Cambrian to Pliocene age – all of which are from well-constrained stratigraphic sections in Israel. We present imaging and chemical characterization techniques that provide useful information on interpreting the resulting U–Pb ages and discuss the complexity of in situ dolomite dating in terms of textural features that may affect the results. Textural examinations indicate zonation and mixing of different phases at the sub-millimeter scale (< 1 µm), and thus Tera–Wasserburg ages represent mixed dates of early diagenesis and some later epigenetic dolomitization event(s). We conclude that age mixing at the sub-millimeter scale is a major challenge in dolomite dating that needs to be further studied and note the importance of matrix-matched standards for reducing uncertainties of the dated material.
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Korinevsky, V. G., K. A. Filippova, V. A. Kotlyarov, E. V. Korinevsky e D. A. Artemyev. "Trace-elements in minerals from unusual rocks of the Southern Urals". LITHOSPHERE, n.º 2 (12 de junho de 2019): 269–92. http://dx.doi.org/10.24930/1681-9004-2019-19-2-269-292.
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Research subject. This articles presents the data obtained in the course of 75 analytical studies on a wide range of minerals (amphiboles, pyroxenes, garnets, spinels, olivines, anorthites, corundums, epidotes, apatites, clinochlore, dolomite, calcite, zircon) contained in igneous and metamorphic Southern Urals rocks. In addition, information is provided about the content of trace elements, including rare earth (REE) ones, in these rocks. The data on the content of trace elements in some minerals are presented for the first time (höegbomite, sapphirine, zoisite, clinozoisite, gedrite, cummingtonite, anthophyllite, potassium-magnesiohastingsite). Materials and methods. A petrographic analysis of rocks containing the minerals under study was carried out. A particular attention was paid to petrographic analysis of rocks containing the minerals under study was carried out. A particular attention was paid to “fresh” rocks, containing the mineral under study which rarely occur in the Urals. These rocks feature inclusions of serpentinite melange in the form of plates and lenses among the metamorphic strata (schists, gneisses, and amphibolites) and are characterized by the preservation of primary structures, relative chemical homogeneity, as well as the presence of simultaneous growth surfaces between most minerals. Of particular research interest were minerals from rocks, the composition of which had been relatively poorly studied (pyroxene-amphibole anorthite gabbro and gabbro-amphibolites, scapolite rocks, hornblendite, gedrite-cummingtonite-anthophyllitic crystallo-schists and amphibolites, ore-less carbonatites). The composition of mineral samples was determined using a scanning microscope REMMA-202 M equipped with an energy dispersive console and a mass-spectrometer Agilent 7700x (ICP-MS and LA-ICP-MS methods). Results. Petrographic characteristics of the rocks containing the minerals under study are given. The geographical coordinates of locations, where mineral sampling was performed, are provided. The content of trace elements is shown to vary greatly within related species of minerals (amphiboles, garnets, pyroxenes, olivines, epidotes, spinels, mica, etc.), with the fluctuations being independent of the alkalinity of host rocks or their geological nature.Conclusions. For the first time, a significant role of zoisite and clinozoisite in the process of concentrating trace elements, including REE, has been revealed. The role of apatite as one of the main mineral concentrators of REE has not been confirmed either in the main and ultrabasic rocks, or in some calcite-dolomite carbonatites.
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KLEIN, CARLA, e ANA MARIA PIMENTEL MIZUSAKI. "Cimentação Carbonática em Reservatórios Siliciclásticos - O Papel da Dolomita -". Pesquisas em Geociências 34, n.º 1 (30 de junho de 2007): 91. http://dx.doi.org/10.22456/1807-9806.19465.
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Carbonates are important diagenetic cements in siliciclastic rocks thus important to determine these rocks as hydrocarbon reservoirs. The cement is the material had chemically precipitated partial or totally pore filling, affecting rock values of porosity and permeability. The acknowledgment of diagenetic patterns those are associated to the carbonatic cement precipitation and their impacts in the reservoirs quality can decrease the risks of exploration and exploitation of new reservoirs. Therefore is necessary the knowledge of origin and processes of carbonate cement’s precipitation. These cements have distribution patterns, mineralogy, textures and isotopic compositions which vary spatial and temporally, depending of perform conditions in each diagenetic environment. One of the most important diagenetic cement is dolomite and the dolomite’s group is compound by dolomite and ankerite. These minerals can be differentiated by analytical techniques such as optical petrography, staining techniques, cathodoluminescence, scanning electron microscopy and isotopes. Besides that, dolomite cement shape in a reservoir can display different forms: rhombs, poikilotopic and saddle in a variety of dimensions, pore filling, replacing detrital carbonate grains, concretions, nodules or stratified layers. Primaries calcite and aragonite replaced can promote precipitation of dolomite through increase of temperature and by presence of Mg-being fluids. The main entrance conditions to form dolomitic cement are: (i) alkaline solutions from pre-existence rocks weathering or evaporitc environments; (ii) marine waters; (iii) clay alteration; (iv) CaCO3 polymorphs dissolution; (v) dissolution of bioclasts. An interesting example of dolomitic cementation is the Carmópolis Member of the Muribeca Formation, hydrocarbon reservoir of the Camorim Field (Sergipe-Alagoas Basin, northeastern Brazil).
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Xiao, Hong, Quan Jun Liu, Mei Guang Jiang e Jun Long Yang. "The Flotation Test of Collophanite in Yunnan Province". Advanced Materials Research 813 (setembro de 2013): 259–62. http://dx.doi.org/10.4028/www.scientific.net/amr.813.259.
Texto completo da fonteResumo:
The samples belong to low grade siliceous collophanite. Main useful mineral is cellophane and main gangue minerals are quartz , calcite and dolomite. The grade of P2O5 is 21.98% and the grade of SiO2 is 31.34%. Through the straight-reverse flotation, the phosphate concentrates with a grade of 27.68% and the recovery of 83.04% were obtained. The content of MgO is 0.92% in phosphate concentrates.