biotite schist
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2022 ◽  
Vol 44 (1) ◽  
Author(s):  
Maria Madalena Rinaldi ◽  
Ana Maria Costa ◽  
Juaci Vitória Malaquias ◽  
Eder de Souza Martins

Abstract The present study aimed to evaluate the physicochemical characteristics and shelf life of P. cincinnata BRS Sertão Forte fruits produced with conventional fertilization recommended for passion fruit, conventional organic fertilization, organic fertilization enriched with biotite schist, conventional fertilization with replacement of the potassium source and chemical fertilization only and the mineral nutrition of plants stored under ambient and refrigerated conditions. Analyses of pH, soluble solids, titratable acidity, ratio, color, texture and mass loss were performed. Fertilizers differed in terms of nutrient absorption associated with protein synthesis (N, S, B, Cu, Mn, Zn), especially where soil remineralizer was applied. Treatments without fertilization and that with organic fertilization enriched with biotite schist soil remineralizer also positively influenced fruit physicochemical properties such as color and texture. Fruits stored under refrigeration conditions showed the best results for the conservation of their qualitative characteristics. Under the conditions of the present study, it could be concluded that the postharvest life of P. cincinnata fruits stored under refrigeration at 100C is at least 60 days. This period is 30 days under ambient conditions.


Geofluids ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Jianguo Wang ◽  
Ting Zuo ◽  
Xianglong Li ◽  
Zihao Tao ◽  
Jun Ma

In order to study the fractal characteristics of the pomegranate biotite schist under the effect of blasting loads, a one-dimensional SHPB impact test was carried out to test the dynamic compressive strength, damage morphology, fracture energy dissipation density, and other parameters of the rocks under different strain rates; besides, sieve tests were conducted to count the mass fractal characteristics of the crushed masses under different strain rates to calculate the fractal dimension of the crushed rock D . Finally, the relationships between fractal dimension and dynamic compressive strength, crushing characteristics, and energy dissipation characteristics were analysed. The results show that under different impact loads, the strain rate effect of the rock is significant and the dynamic compressive strength increases with the increasing strain rate, and they show a multiplicative power relationship. The higher the strain rate of the rock, the deeper the fragmentation and the higher the fractal dimension, and the fractal dimension and rock crushing energy density are multiplied by a power relationship. By performing the comparative analysis of the pomegranate biotite schist, a reasonable strain rate range of 78.75 s-1~82.51 s-1 and a reasonable crushing energy consumption density range of 0.78 J·cm-3~0.92 J·cm-3 were determined. This research provides a great reference for the analysis of dynamic crushing mechanism, crushing block size distribution, and crushing energy consumption of the roadway surrounding rock.


2021 ◽  
Author(s):  
Bernardo Cesare ◽  
Fabrizio Nestola

<p>Common (anhydrous) Fe-Mg-Ca-Mn garnet, the archetypal cubic mineral, has been recently discovered to be tetragonal in metapelites and metabasites from low-temperature regional metamorphic terranes (Cesare et al., 2018).</p><p>Despite the differences in bulk rock composition and pressure conditions, such low-T tetragonal garnets share common chemical features, namely high grossular (>25 mol%) and low pyrope (<7 mol%) contents. Similar compositions are documented in other contexts worldwide, both in blueschists-eclogites and in phyllites, including the metapelites from the garnet zone of the iconic Barrovian metamorphism of the Scottish highlands (Viete et al., 2011).</p><p>We have analysed a garnet crystal from a chlorite-biotite schist collected at the Barrow’s garnet zone in Glen Esk. The unit cell parameters were refined using diffraction reflections between 1.20 and 0.55 Å providing a tetragonal cell with a = 11.5731(5) Å and c = 11.5887(8) Å and volume V = 1552.15(15) Å3. Systematic absences analysis on complete intensity data collected up to 2theta = 80° indicated I41/acd space group confirming the cell parameters refinement.</p><p>Therefore, the garnet is tetragonal and not cubic, as suggested by its weak birefringence under crossed polarizers.</p><p>These results show that the tetragonal structure of common Fe-Mg-Ca-Mn garnet is verified whenever this mineral displays the Ca-rich, Mg-poor composition often observed in low-T metamorphic rocks. And support the hypothesis that the lowering of symmetry is composition-dependent.</p><p> </p><p>References</p><p>Cesare, B., et al. Garnet, the archetypal cubic mineral, grows tetragonal. Sci Rep <strong>9</strong>, 14672 (2019).</p><p>Viete, D.R., et al. The nature and origin of the Barrovian metamorphism, Scotland: Diffusion length scales in garnet and inferred thermal time scales. J. Geol. Soc. London <strong>168</strong>, 115–132 (2011).</p><p> </p>


Author(s):  
Cintia Carla Niva ◽  
Julia Cora Segat ◽  
Dilmar Baretta ◽  
Carolina Riviera Duarte Maluche Baretta ◽  
Maria Inês Lopes de Oliveira ◽  
...  

Abstract: The objective of this work was to evaluate the possible adverse effects of rock dusts on the avoidance behavior of earthworms and collembolans, as well as on the survival and reproduction of enchytraeids, in ecotoxicological tests using artificial and natural soils. The tests were performed following international guidelines (ISO 17512-2/2011, ISO 11267/1999, and NBR ISO 16387/2012), with some adaptations, in order to evaluate the effect of dusts from two silicate rocks, biotite schist and phonolite, at the concentrations of 0, 0.1, 1.0, 10, and 100%, in artificial and natural (Arenosol and Ferralsol) soils. The avoidance behavior of the earthworm Eisenia andrei and the collembolan Folsomia candida was evaluated, as well as the survival and reproduction of the enchytraeid Enchytraeus sp. Biotite schist and phonolite affected negatively earthworms when applied to the soil at concentrations equal to or higher than 1.0%. The observed effect was associated to the greater presence of salts, especially in the phonolite, and to changes in soil texture when higher concentrations were used. Negative effects on collembolans and enchytraeids were verified at concentrations of 10% or using pure rock dusts. Agronomic rates smaller than 1.0% (approximately 20 Mg ha-1) rock dusts do not cause avoidance behavior or reduction in the survival and reproduction of invertebrates in the soil.


2020 ◽  
Author(s):  
Subhash Singh ◽  
Tapas Kumar Biswal

<p>South Delhi orogeny is constrained by correlating the deformational fabric with geochronology of the granites and metasediments around Beawar- Rupnagar-Babra, Rajasthan, NW India. The area consists of metaconglomerate, calcareous schist, mica schist and amphibolite. These were deformed by three stages of deformation(D<sub>1-3</sub>) and intruded by four types of granite plutons (G<sub>1-4</sub>). The D<sub>1</sub> deformation produced F<sub>1</sub>, reclined/recumbent folds with S<sub>1</sub> axial planar fabric in greenschist facies metamorphic condition. The D<sub>2</sub> deformation produced NE-SW trending F<sub>2</sub> folds coaxial with F<sub>1</sub>(type 3 interference pattern), crenulations and F<sub>2</sub>-axial parallel ductile shear zones.  The D<sub>3</sub> deformation produced NW-SE F<sub>3 </sub>folds, which superimposed on F<sub>1</sub> and F<sub>2</sub> to create type 1 and 2 interference pattern. Granites carry pervasive S<sub>1</sub> fabric. In G<sub>1-3</sub> granites, the S<sub>1</sub> is characterized by low temperature deformation fabric marked by bulging recrystallization of quartz. The G<sub>4</sub> granite (namely Sewariya granite) contains magmatic to submagmatic fabric and the S<sub>1</sub> fabric in it is a high temperature deformation fabric and lies parallel to magmatic fabric in the rock. Plagioclase is dynamically recrystallized by subgrain rotation and grain boundary migration and quartz shows chess board twinning. We interpret that the G<sub>4</sub> granite is syntectonic and G<sub>1-3 </sub>were pre-tectonic to D<sub>1</sub> deformation.  U-Pb data (SHRIMP method) of G<sub>1</sub>, G<sub>2 </sub>and G<sub>4 </sub>granites yield Concordia age calculated with <sup>206</sup>Pb/<sup>238</sup>U and <sup>207</sup>Pb/<sup>235</sup>U ratio at ~982 Ma, ~992 Ma and ~878 Ma respectively. Thus the South Delhi orogeny is constrained by the age of G<sub>4</sub> granite at ~ 878 Ma (~ 870 Ma).  The G<sub>1-3 </sub>granites are pre- Delhi orogeny and probably constrain the age of rifting of the Delhi basin. EPMA Th-U-total Pb monazite geochronology of the garnet-staurolite-quartz-feldspar-biotite schist from the basal conglomerate zone shows three distinct ages, ca. 1611 Ma, 864 Ma and 718 Ma.  Correlating with granite SHRIMP age, the ~ 864 Ma corresponds to Delhi metamorphism and D<sub>1</sub> deformation (~ 870 Ma). The event ca. 1611 Ga probably belongs to pre-Delhi age, which is observed in nearby pre-Delhi localities like Sandmata terrane.</p><p>Keywords: Deformational fabric, geochronology, metaconglomerate, granite and geochronology.</p>


2020 ◽  
Vol 115 (1) ◽  
pp. 51-77
Author(s):  
Xuyang Meng ◽  
Jeremy Richards ◽  
Jingwen Mao ◽  
Huishou Ye ◽  
S. Andrew DuFrane ◽  
...  

Abstract The Tongkuangyu copper deposit in the Zhongtiaoshan region, southern Trans-North China orogen, is hosted by a poorly constrained sequence of Paleoproterozoic volcano-sedimentary (quartz-sericite schist and biotite schist) and granitic rocks that have been metamorphosed to lower greenschist facies and variably deformed. The deposit has previously been proposed to be either a porphyry-type or a sediment-hosted stratiform Cu deposit, and its age of formation has been debated. The quartz-sericite schist is interpreted to be a felsic crystal tuff and consists of angular quartz crystals in a fine-grained sericite-altered matrix. Two quartz-sericite schist samples yielded zircon U-Pb upper concordia intercept ages of 2512 ± 12 (2σ, mean square of weighted deviates [MSWD] = 0.19) and 2335 ± 16 Ma (2σ, MSWD = 0.80). Biotite schist, which is interleaved locally with the quartz-sericite schist and is interpreted to be a basaltic-andesitic sill, yielded a younger zircon U-Pb upper concordia intercept age of 2191 ± 10 Ma (2σ, MSWD = 1.7). Five samples of granodiorite and granodiorite porphyry that intruded the schist sequence yielded similar zircon U-Pb ages, with a weighted mean upper concordia intercept age of 2182 ± 7 Ma (2σ, MSWD = 1.3). These results suggest that the volcanic sequence was deposited between ∼2.5 and 2.3 Ga and was intruded by basaltic-andesitic sills and a suite of granodiorite and granodiorite porphyry intrusions at ∼2.19 to 2.18 Ga. Two stages of copper mineralization are interpreted to have formed after pervasive sericite alteration of the felsic volcanic rocks. Stage 1 mineralization includes disseminated and deformed quartz veinlets containing chalcopyrite ± pyrite ± magnetite ± molybdenite associated with biotite ± K-feldspar alteration in granodiorite porphyry and schist. Stage 2 comprises undeformed quartz-chlorite-carbonate veins with bornite ± chalcopyrite ± magnetite associated with local chlorite and silicic alteration. Allanite crystals intergrown with chalcopyrite in the granodiorite porphyry yielded an approximate concordia U-Pb age of 2115 ± 31 Ma (2σ, MSWD = 2.3). Two molybdenite samples in a deformed quartz-chalcopyrite-molybdenite vein yielded Re-Os model ages of 2106 ± 9 and 2089 ± 9 Ma (2σ), consistent with previously published results. Hydrothermal monazite grains with Cu-Fe sulfide inclusions in the granodiorite porphyry, quartz-sericite schist, and undeformed chlorite-bornite-quartz veins yielded much younger U-Pb upper concordia intercept ages of 1832 ± 16 (2σ, MSWD = 0.48), 1810 ± 14 (2σ, MSWD = 0.92), and 1809 ± 12 Ma (2σ, MSWD = 0.38), respectively. The results are in agreement with four Re-Os model ages for pyrite mineral separates from undeformed quartz-sulfide veins, which yielded a weighted mean age of 1807 ± 4 Ma (2σ, n = 4, MSWD = 0.42). In contrast, hydrothermal rutile crystals in the quartz-sericite schist and biotite schist yielded a range of roughly concordant ages between 2.1 and 1.8 Ga, reflecting isotopic disturbance. We interpret these results to indicate original copper mineralization at ∼2.1 Ga that is significantly later than the granodiorite (∼2.18 Ga) and schists (∼2.5–2.2 Ga), followed by hydrothermal remobilization and metamorphism at ∼1.8 Ga. The metavolcanic and granodiorite porphyry host rocks, alteration styles, and disseminated and veinlet form of the earlier mineralization are strongly reminiscent of porphyry Cu deposits, and ages of ∼2.1 Ga have been reported for one intrusion and three volcanic rock samples from the district. The Tongkuangyu, therefore, represents one of the oldest known porphyry copper deposits. Remobilization of copper occurred at ∼1.8 Ga during the Zhongtiao orogeny.


Author(s):  
Giuliano Marchi ◽  
Douglas Ramos Guelfi-Silva ◽  
Juaci Vitória Malaquias ◽  
Luiz Roberto Guimarães Guilherme ◽  
Carlos Roberto Spehar ◽  
...  

Abstract: The objective of this work was to evaluate the solubility of the micronutrients copper, nickel, and zinc, chemically extracted from silicate agrominerals, as alternative sources of potassium for lettuce (Lactuca sativa) and rice (Oryza sativa) cultures, as well as their availability to the plants. The micronutrient contents of five agrominerals (alkaline ultramafic, biotite schist, volcanic breccia, phlogopite schist, and mining by-product from Chapada) were evaluated, after being extracted by the citric acid, hydrochloric acid, diethylenetriaminepentaacetic acid, 3051A, neutral ammonium citrate, and Mehlich-3 methods. The agrominerals, at the doses of 0 (control), 200, 400, and 600 kg ha-1 K, were mixed to soil where lettuce and rice were cultivated. The agrominerals presented a low solubility of Ni, Cu, and Zn, with lower contents in lettuce shoots and rice grains than the corresponding soluble standards in sulfate form. The availability of micronutrients to the plants increased with the use of agrominerals, in comparison with the control. Similarities were observed in micronutrient solubility and availability between the different groups of agrominerals. The solubility and availability of Cu, Ni, and Zn depend on the solubility of the minerals that compose the agrominerals.


2019 ◽  
Vol 35 (2) ◽  
pp. 363-375 ◽  
Author(s):  
QIN ShengKai ◽  
◽  
ZHANG ZeMing ◽  
JIANG YuanYuan ◽  
CHEN YanFei ◽  
...  

2013 ◽  
Vol 5 (3) ◽  
Author(s):  
Yeşim Özen ◽  
Fetullah Arik

AbstractThe Inkaya Cu-Pb-Zn-(Ag) mineralization, located about 20 km west of the Simav (Kütahya-Turkey), is situated in the northern part of the Menderes Massif Metamorphics. The mineralization is located along an E-W trending fault in the Cambrian Simav metamorphics consisting of quartz-muscovite schist, quartz-biotite schist, muscovite schist, biotite schist and the Arıkayası formation composed of marbles. Mineralized veins are 30–35 cm in width. The primary mineralization is represented by abundant galena, sphalerite, chalcopyrite, pyrite, fahlore and minor amounts of cerussite, anglesite, digenite, enargite, chalcocite, covellite, bornite, limonite, hematite and goethite with gangue quartz.Fluid inclusion studies on the quartz samples collected from the mineralized veins indicate that the temperature range of the fluids is 235°C to 340°C and the salinities are 0.7 to 4.49 wt. % NaCl equivalent. The wide range of homogenization temperatures indicates that two different fluid generations were trapped in quartz.Sulfur isotope studies of the sulfide minerals showed that all of the δ 34S values are between −2.1 and 2.6 per mil. These values are a typical range for hydrothermal sulfide minerals that have sulfur derived from a magmatic source.Pyrite-galena and pyrite-chalcopyrite sulfur isotope fractionation is consistent with an approach to isotopic equilibrium, and calculated temperatures are 254.6 and 277.4°C for pyrite-galena and 274.7°C for pyrite-chalcopyrite. The microthermometric data and sulfur isotope thermometry indicate the existence of a hydrothermal fluid that circulated along the fault crossing the Simav metamorphics and Arıkayası formation.Fluid inclusion and sulfur isotope thermometry can be used in combination with ore petrographical and geological information to provide site-specific targets for meso-hypothermal metal concentrations.


2010 ◽  
Vol 39 (9) ◽  
pp. 1883-1888 ◽  
Author(s):  
Adônis Moreira ◽  
Nand Kumar Fageria ◽  
Gilberto Batista de Souza ◽  
Alfredo Ribeiro de Freitas

The objective of this work was to evaluate the effects of cattle manure, reactive natural phosphate and biotite schist on the soil fertility, yield and nutritional status of Megathyrsus spp. cv. Massai. The experiment was conducted under field conditions, in a dystrophic Red Yellow Latosol (Oxisol). It was used a randomized block experimental design with the following treatments: three natural reactive rock phosphate from Algeria (Djebel-Onk) doses (0, 100 and 200 kg ha-1 of P2O5), three biotite schist doses (0, 150 and 300 kg ha-1 of K2O) and three cattle manure doses (0, 20 and 40 t ha-1). The application of natural phosphate increased dry matter yield, however, application of cattle manure and biotite schist did not influence this variable. Foliar levels of nitrogen, potassium and magnesium (cattle manure), phosphorous and boron (natural rock phosphate) and potassium (biotite schist) were influenced by the applied fertilizer doses. Only the levels of phosphorous in the soil and in the plant and levels of magnesium and boron in the plant show interaction with dry matter yield of Massai cultivar.


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