scholarly journals EFFECTS OF IGNEOUS INTRUSION ON THE MINERALOGICAL CONTENT OF IRATI FORMATION, PARANÁ BASIN, IN SAPOPEMA (PR), SOUTHERN BRAZIL

2019 ◽  
Vol 4 (3) ◽  
pp. 350-360
Author(s):  
Werlem Holanda ◽  
Anderson Costa dos Santos ◽  
Camila Cardoso Nogueira ◽  
Luiz Carlos Bertolino ◽  
Sérgio Bergamaschi ◽  
...  
Keyword(s):  
Host Rock ◽  
Mineral Assemblage ◽  
Sedimentary Basins ◽  
Southern Brazil ◽  
X Ray Diffraction ◽  
X Ray ◽  
Mineralogical Association ◽  
Irati Formation ◽  
Igneous Intrusions ◽  
Rock Association

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.

Redefinition of thérèsemagnanite, NaCo4(SO4)(OH)6Cl·6H2O: new data and relationship to ‘cobaltogordaite’

2018 ◽  
Vol 82 (1) ◽  
pp. 159-170 ◽  
Author(s):  
Anatoly V. Kasatkin ◽  
Jakub Plášil ◽  
Radek Škoda ◽  
Dmitriy I. Belakovskiy ◽  
Joe Marty ◽  
...  
Keyword(s):  
Crystal Structure Data ◽  
New Mineral ◽  
X Ray Diffraction ◽  
Oh Groups ◽  
X Ray ◽  
International Mineralogical Association ◽  
Mineralogical Association ◽  
Holotype Specimen ◽  
Cl Atoms ◽  
The Ideal

ABSTRACTThérèsemagnanite was originally described from the Cap Garonne mine, Var, France. Its ideal formula was reported as (Co,Zn,Ni)6(SO4)(OH,Cl)10·8H2O; without crystal structure data, only the powder X-ray diffraction pattern was given. Revision of the holotype material revealed that thérèsemagnanite is identical to ‘cobaltogordaite’ (IMA2014-043), recently described from the Blue Lizard mine, Utah, USA. Thérèsemagnanite is thus redefined in accordance with the new data obtained for the neotype specimen from Blue Lizard (formerly the holotype specimen of ‘cobaltogordaite’) and ‘cobaltogordaite’ has been discredited by the International Mineralogical Association Commission on New Mineral Nomenclature and Classification (IMA CNMNC). Thérèsemagnanite has the ideal, end-member formula NaCo4(SO4)(OH)6Cl·6H2O. The empirical formulae of the holotype (Cap Garonne) and the neotype (Blue Lizard), both based on microprobe analyses and calculated on the basis of 17 O + Cl atoms per formula unit (with fixed 6 OH groups and 6 H2O molecules; H content is calculated by stoichiometry) are (Na0.64K0.09)Σ0.73(Co2.35Zn1.22Ni0.50)Σ4.07S1.02O3.98(OH)6Cl1.02·6H2O and Na1.01(Co1.90Zn1.37Ni0.48Cu0.15Mn0.05)Σ3.95S1.03O4.09(OH)6Cl0.91·6H2O, respectively. Thérèsemagnanite is trigonal,P$\overline 3 $,a= 8.349(3),c= 13.031(2) Å,V= 786.6(4) Å3and Z = 2 (neotype). The strongest powder X-ray diffraction lines are [dobsin Å (hkl) (Irel)]: 13.10 (001)(100), 6.53 (002)(8), 4.173 (110)(4), 3.517 (112)(5), 2.975 (104, 10$\overline 4 $)(4), 2.676 (211)(5) and 2.520 (12$\bar 2$)(5) (neotype). Thérèsemagnanite is a cobalt analogue of gordaite, NaZn4(SO4)(OH)6Cl·6H2O. These minerals represent the gordaite group, accepted by the IMA CNMNC.

pH Dependence of the Aqueous Dissolution Rates of Perovskite and Zirconolite at 90°C

1994 ◽  
Vol 353 ◽  
Author(s):  
Peter J McGlinn ◽  
K. P. Hart ◽  
E. H. Loi ◽  
E. R. Vance
Keyword(s):  
Mineral Assemblage ◽  
Perovskite Phase ◽  
Ph Dependence ◽  
Xrd Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Dissolution Behaviour ◽  
Alkaline Conditions ◽  
Ph Conditions ◽  
Sem Investigation

AbstractPerovskite and zirconolite are two of the major phases of the Synroc titanate mineral assemblage. Their aqueous durability under a range of pH conditions at 90°C has been examined. Solution analysis, electron microscopy and X-ray diffraction have been used to investigate the dissolution behaviour of these phases, and a perovskite phase doped with Nd, Sr and Al, using buffered solutions at pH levels of 2.1, 3.7, 6.1, 7.9 and 12.9. After 43 days of leaching, Ca and Ti extractions from perovskite and zirconolite show only a weak pH-dependence.SEM investigation of the samples leached at pH 2.1, 6.1 and 12.9 showed that a titanaceous surface layer formed on the perovskite specimens. XRD analysis of the perovskite samples showed that anatase formed on the leached surface at acidic and neutral pHs, but not under alkaline conditions, and that minor amounts of rutile also formed. In the leached perovskite specimens doped with Nd, Sr and Al, no rutile was found by XRD and anatase was only detected in the sample leached at pH 2.1. There were no detectable changes in the leached zirconolite samples examined by SEM and XRD.

Alteration Minerals in Granitic Rock at Ashio as Radionuclide Adsorption Materials

1994 ◽  
Vol 353 ◽  
Author(s):  
S. Hamasaki ◽  
K. Tsukimura ◽  
K. Fujimoto ◽  
K. Omura ◽  
R. Ikeda
Keyword(s):  
Host Rock ◽  
Mineral Assemblage ◽  
Granitic Rock ◽  
Drill Core ◽  
Radionuclide Transport ◽  
Central Japan ◽  
X Ray ◽  
Alteration Minerals ◽  
Analytical Scanning Electron Microscopy ◽  
Scanning Electron

AbstractAlteration minerals from a drill-core (maximum depth 2002 m) in the granitic rock at Ashio, central Japan, were studied by optical microscopy, X-ray diffractometry and analytical scanning electron microscopy. In the host rock, biotite is altered to chlorite and plagioclase to illite. Calcite has precipitated in veinlets and grain boundaries. The host rock close to fractures is strongly altered, whereas the rocks distant from fractures are less altered. Quartz, illite, chlorite, laumontite and calcite have precipitated on fracture walls. The alteration minerals are estimated to have formed in the range 140–200°C, higher than the present temperature (13°96°C). The chemical composition of the ground water in the granitic rock at Ashio was estimated thermodynamically from the mineral assemblage. The alteration reaction of palgioclase and the precipitation of calcite may occur simultaneously. The alteration minerals formed in the host rock and in the fractures may adsorb radionuclides effectively, and thus may inhibit radionuclide transport to biosphere.

Effects of Chlorite Alteration on Uranium Redistribution in Koongarra, Australia

1990 ◽  
Vol 212 ◽  
Author(s):  
Takashi Murakami ◽  
Hiroshi Isobe ◽  
Robert Edis
Keyword(s):  
Diffraction Study ◽  
Host Rock ◽  
Uranium Concentration ◽  
Major Constituent ◽  
X Ray Diffraction ◽  
Ore Deposit ◽  
X Ray ◽  
Uranium Ore ◽  
Iron Minerals ◽  
Uranium Migration

ABSTRACTThe relevance of alteration of chlorite, one of the major constituent minerals of the host rock to uranium ore at Koongarra, to the redistribution of uranium in the vicinity of the ore deposit has been examined. The chlorite alteration is produced by weathering; chlorite is transformed to vermiculite, through regularly interstratified chlorite/vermiculite. The Fe released from chlorite reprecipitates to form iron minerals, possibly ferrihydrite. Vermiculite is then replaced by kaolinite (and possibly smectite), further releasing Fe. On the millimeter scale, an alpha autoradiography study has shown that uranium concentrations are qualitatively proportional to the extent of the alteration; altered chlorite grains having higher uranium concentration. On the meter scale, the X-ray diffraction study has revealed that the abundances of chlorite, vermiculite, and kaolinite correspond well to the low, intermediate, and high uranium concentration zones, respectively. These suggest that the interaction of the uraniferous solution with chlorite causes the alteration of chlorite and the precipitation and sorption of uranium in the alteration products from the solution, and thus, the uranium migration is retarded at Koongarra.

Phlogopite from the Ventaruolo subsynthem volcanics (Mt Vulture, Italy): a multi-method study

2007 ◽  
Vol 71 (5) ◽  
pp. 519-537 ◽  
Author(s):  
E. Schingaro ◽  
F. Scordari ◽  
S. Matarrese ◽  
E. Mesto ◽  
F. Stoppa ◽  
...  
Keyword(s):  
Volcanic Activity ◽  
Electron Microprobe ◽  
Host Rock ◽  
Microprobe Analysis ◽  
Electron Microprobe Analysis ◽  
Structural Data ◽  
Underground Water ◽  
Middle Pleistocene ◽  
X Ray Diffraction ◽  
X Ray

AbstractVolcanic activity at Mt Vulture lasted throughout the Middle Pleistocene and produced SiO2- undersaturated volcanics. Deposits from the Monte Vulture stratovolcano have been classified into four subsynthems and clustered into the Barile Synthem. In the present investigation, trioctahedral micas from the uppermost units (the Ventaruolo Subsynthem) of the Barile Synthem are considered. The samples are labelled VUT187. The phlogopitic micas were separated from the host rock (an olivinefoidite) and underwent chemical (electron microprobe analysis - EMPA and C-H-N), structural (singlecrystal X-ray diffraction) and spectroscopic (Mössbauer) investigations.The EMPA yielded: MgO (17.62–21.89 wt.%), FeOtot (5.98–9.78 wt.%), TiO2 (1.81–3.92 wt.%) and Al2O3 (14.47–17.98 wt.%), with H2O contents = 2.86 (±0.42) wt.% determined by C-H-N analyses. Mössbauer investigation provided [VI]Fe2+ = 12.6%, [VI]Fe3+ = 87.4%. The chemical and structural data are consistent with the occurrence of Ti-oxy, [VI]M2+ + 2(OH)– ⇋ [VI]Ti4+ + 2O2– + H2, and M3+-oxy substitutions, [VI]M2+ + (OH)– ⇋ [VI]M3+ + O2– + 1/2H2, with M3+ = Fe3+, Al3+. In particular, Fe3+-oxy substitution has affected the Fe2+/Fe3+ ratioin the studied sample. This is probably due to the fact that interaction with underground water or a hydrothermal system may have altered the oxygen fugacity and raised the Fe3+ content of VUT187 phlogopite with respect to magmatic values.

Geochemical and Palaeo-Climate Significance of the 56 Submember of Majiagou Formation in Northern Shaanxi Ordovician Salt Basin

2013 ◽  
Vol 868 ◽  
pp. 159-163
Author(s):  
Wen Qiang Gong ◽  
Yong Sheng Zhang
Keyword(s):  
Mineral Assemblage ◽  
Chemical Elements ◽  
Vertical Section ◽  
Major Elements ◽  
X Ray Diffraction ◽  
X Ray ◽  
Northern Shaanxi ◽  
Reducing Environment ◽  
Trace And Major Elements ◽  
Semi Arid

In order to investigate the geochemical and palaeo-climate significance of the 56submember of majiagou formation, mineral assemblage and inorganic geochemistry features of SJ1 well were particular analyzed by X-ray diffraction and SEM characterization. The result of trace and major elements about mudstone interlayer samples showed that the mineral assemblage of clay in this area was mainly illite and chlorite, and these two complement were relatively complementd from each other. Mn, Sr, P, Cu, Rb/Sr, Sr/Cu, Fe/Mn, (Fe+Al)/(Ca+Mg) ,V/(V+Ni) and Cu/Zn had the simialr variation tendencies on the vertical section. Upper and middle cycle could be divided into five and four sub-cycles, respectively. The analysis on clay minerals and chemical elements revealed that the paleoclimate of the 56Submember of Majiagou was formed in semi-arid and arid with deepwater and reducing environment. The palaeo-climate of upper cycle was more arid than the middle, and it had lower frequency on the secondary wet-arid change, which was regarded to be conducive to the formation of potassium.

scholarly journals Predictive Models of Mineralogy from Whole-Rock Assay Data: Case Study from the Productora Cu-Au-Mo Deposit, Chile

2019 ◽  
Vol 114 (8) ◽  
pp. 1513-1542 ◽  
Author(s):  
Angela Escolme ◽  
Ron F. Berry ◽  
Julie Hunt ◽  
Scott Halley ◽  
Warren Potma
Keyword(s):  
Value Chain ◽  
Mineral Assemblage ◽  
Qualitative Approach ◽  
Geochemical Data ◽  
X Ray Diffraction ◽  
Data Set ◽  
X Ray ◽  
Quantitative Estimates ◽  
Mineral Phases

Abstract Mineralogy is a fundamental characteristic of a given rock mass throughout the mining value chain. Understanding bulk mineralogy is critical when making predictions on processing performance. However, current methods for estimating complex bulk mineralogy are typically slow and expensive. Whole-rock geochemical data can be utilized to estimate bulk mineralogy using a combination of ternary diagrams and bivariate plots to classify alteration assemblages (alteration mapping), a qualitative approach, or through calculated mineralogy, a predictive quantitative approach. Both these techniques were tested using a data set of multielement geochemistry and mineralogy measured by semiquantitative X-ray diffraction data from the Productora Cu-Au-Mo deposit, Chile. Using geochemistry, samples from Productora were classified into populations based on their dominant alteration assemblage, including quartz-rich, Fe oxide, sodic, potassic, muscovite (sericite)- and clay-alteration, and least altered populations. Samples were also classified by their dominant sulfide mineralogy. Results indicate that alteration mapping through a range of graphical plots provides a rapid and simple appraisal of dominant mineral assemblage, which closely matches the measured mineralogy. In this study, calculated mineralogy using linear programming was also used to generate robust quantitative estimates for major mineral phases, including quartz and total feldspars as well as pyrite, iron oxides, chalcopyrite, and molybdenite, which matched the measured mineralogy data extremely well (R2 values greater than 0.78, low to moderate root mean square error). The results demonstrate that calculated mineralogy can be applied in the mining environment to significantly increase bulk mineralogy data and quantitatively map mineralogical variability. This was useful even though several minerals were challenging to model due to compositional similarities and clays and carbonates could not be predicted accurately.

Discreditation of tombarthite-(Y)

2018 ◽  
Vol 82 (5) ◽  
pp. 1131-1139
Author(s):  
Henrik Friis
Keyword(s):  
Original Description ◽  
Chemical Analyses ◽  
X Ray Diffraction ◽  
History Museum ◽  
X Ray ◽  
International Mineralogical Association ◽  
Mineralogical Association ◽  
Fresh Material ◽  
Heating Scheme ◽  
Quantitative Chemical

ABSTRACTTombarthite-(Y) is discredited as a mineral species. No type material was available, but material used for the original description has been located and neotype material defined. The main reason for the erroneous description of tombarthite-(Y) is the result of chemical analyses being carried out on heated material, which removed elements such as C and F. New semi-quantitative chemical analyses show that at least F is present in the fresh material, but absent after a heating scheme identical to that of the original description. Modern powder X-ray diffraction methods (XRD) confirm that the material identified as tombarthite-(Y) is a mixture of metamict and crystalline phases. Consequently, what was known as tombarthite-(Y) is not a mixture of the same minerals in equal amounts in different samples, but mixtures of various minerals depending on the sample. The main minerals identified are thalénite-(Y), xenotime-(Y) and kainosite-(Y). The discreditation of tombarthite-(Y) relies on new analyses of a large number of samples from the collection of the Natural History Museum (NHM) in Oslo and has been approved by the International Mineralogical Association Commission on New Minerals, Nomenclature and Classification (proposal 16-K).

scholarly journals Yeomanite, Pb2O(OH)Cl, a new chain-structured Pb oxychloride from Merehead Quarry, Somerset, England

2015 ◽  
Vol 79 (5) ◽  
pp. 1203-1211 ◽  
Author(s):  
R. W. Turner ◽  
O. I. Siidra ◽  
M. S. Rumsey ◽  
Y. S. Polekhovsky ◽  
Y. L. Kretser ◽  
...  
Keyword(s):  
Diffraction Pattern ◽  
Mineral Assemblage ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ideal Formula ◽  
Perfect Cleavage ◽  
The Mean ◽  
The Ideal ◽  
White Streak

AbstractYeomanite, Pb2O(OH)Cl, is a new Pb-oxychloride found in the manganese pod mineral assemblage at Merehead (Torr Works) Quarry, near Cranmore, Somerset, England. Yeomanite is named in joint recognition of Mrs Angela Yeoman (1931–) and her company, Foster Yeoman, who operated Merehead Quarry for aggregate until 2006. The mineral is normally white, occasionally grey, with a white streak and a vitreous to transparent lustre. Invariably intimately associated with mendipite, yeomanite appears to be formed of small, twisted, rope-like fibres growing from the end of columnar mendipite masses, forming loose mats and strands resembling asbestos. Individual fibres are generally <8 mm long, but exceptionally may reach up to 15 mm. There is a perfect cleavage parallel to the long axis of the fibres but this is masked by the fibrous nature, especially as individual fibres break easily. The Dcalc for the ideal formula is 7.303 g/cm3. The mean RI in air at 589 nm is 2.27. The eight strongest reflections in the powder X-ray diffraction pattern [(d in Å) (Intensity) (hkl)] are: 2.880(100)(113); 2.802(78)(006); 3.293(61)(200); 3.770(32)(011); 2.166(22)(206); 1.662(19)(119); 2.050(18)(303); 3.054(17)(105) Yeomanite is orthorhombic, Pnma, a = 6.585(10), b = 3.855(6), c = 17.26(1) Å, V = 438(1) Å3, Z = 4. Yeomanite is a new example of the growing family of lead oxychloride minerals that have a structure based upon oxocentred OPb4 tetrahedra, which, in this mineral, jointly with OHPb3 triangles, form [O(OH)Pb2]+ chains similar to those observed in synthetic Pb2O(OH)I. Yeomanite is structurally related to sidpietersite, penfieldite and laurionite.

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