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Journal articles on the topic 'Sedimentasry manganese'

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Author: Grafiati
Published: 10 December 2022
Last updated: 29 January 2023

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1

Romer, Rolf L., and Uwe Kroner. "Reply to the discussion by J.W.F. Waldron and C.E. White on “Geochemical signature of Ordovician Mn-rich sedimentary rocks on the Avalonian shelf”1Appears in Canadian Journal of Earth Sciences, 2012, 49(6): 772–774 [doi: 10.1139/e2012-004]." Canadian Journal of Earth Sciences 49, no. 6 (June 2012): 775–80. http://dx.doi.org/10.1139/e2012-006.

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In their comment, Waldron and White state that manganese-rich sedimentary rocks of Nova Scotia and Wales are Cambrian and were deposited in a deep-water turbidite basin called “Megumia” rather than on the Avalonian shelf. Available geochronological data are not in conflict with an Early Ordovician deposition age for manganese-rich sedimentary rocks north of the Rheic suture, including those of Nova Scotia and northern Wales. “Megumia” is part of the Avalonian plate, and the manganese-rich sediments were deposited on its shelf.
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2

Bar-Matthews, Miryam. "The genesis of uranium in manganese and phosphorite assemblages, Timna Basin, Israel." Geological Magazine 124, no. 3 (May 1987): 211–29. http://dx.doi.org/10.1017/s0016756800016253.

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AbstractUranium enrichments (up to 4000 ppm) occur in the manganese and phosphorite assemblages of the Lower Cambrian clastic marine sedimentary sequence, Timna Basin, Israel. Two types of mineralization assemblages can be defined. Sedimentary stratabound assemblages consist of uranium-enriched stratiform manganese and phosphatic laminae, diagenetic (type A) manganese nodules composed of pyrolusite and hollandite laminae and phosphorite lenses. Fission-track maps show that the uranium is homogeneously distributed within host manganese and phosphatic minerals of these assemblages. Epigenetic assemblages are mainly composed of manganese- and phosphorite-bearing veins and secondary (type B) manganese nodules with a coronadite dominant mineralogy. Uranium is depleted in these assemblages, relative to the sedimentary stratabound assemblages.The distribution of manganese and phosphorite assemblages has a marked bimodal character. Alternation between manganese and phosphatic laminae in the stratiform deposits reflects cycles of oxidizing and reducing conditions brought about by mixing and stratification of the waters in the Timna semi-closed depositional basins. Compaction of wet sediments led to remobilization and the formation of uranium-enriched manganese nodules at the aerated sediment–water interface, and uranium-enriched phosphorite lenses below the interface in reducing conditions. Epigenesis occurred through the passage of solution fronts which recrystallized the manganese and phosphatic minerals and remobilized metallic elements, particularly uranium which was leached away and is still being remobilized today.The mechanism of uranium uptake in manganese phases is shown most probably to involve adsorbtion of [(UO2)3. (OH)5]+ complexes on precipitating minerals. Uranium is enriched in both the pyrolusite and hollandite laminae of type A nodules, but is particularly concentrated in the former (4000–10000 ppm). Thermodynamic calculations of the relative stabilities of pyrolusite and hollandite suggest that the pH conditions of hollandite formation were close enough to the pH limit of efficient uranium adsorption to inhibit its uptake relative to pyrolusite.
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3

Costa, Marcondes, Oscar Fernandez, Marlis Requelme, Luiz Cláudio Costa, and Carlos Delgado. "SEDIMENTARY MANGANESE DEPOSITS IN CARAJÁS, BRAZIL." Boletim do Museu de Geociências da Amazônia 9, no. 2 (December 31, 2022): 1–38. http://dx.doi.org/10.31419/issn.2594-942x.v92022i2a3mlc.

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The Carajás Mineral Province in Brazil is actually one of the most important in the world because it contains world-class mineral deposits (Fe, Cu, Au, Ni and Mn), partly enriched by lateritic weathering (Fe, Mn, Ni). It carries at least four manganese ore deposits: Azul, Buritirama, Sereno-Conquista and Buriti, of these Azul and Buritirama are productive mines. The Azul deposit is the earliest known and was initially considered as typically lateritic. Further studies show that much of the reserves are classically associated with carbonaceous gray to black mineralized shales and enriched in manganese oxyhydroxides, where cryptomelane is the major ore mineral, enveloped by thick packets of red siltstones and sandstones of lower age Proterozoic (around 2.1 Ga). The mineralogical composition of rocks and ore, isotopic data, abundance of carbonaceous organic matter and the presence of stromatolite structures show deposition in a shallow platform, where the source of manganese and associated metals were mainly of ocean hydrothermal origin, while the sediments of the rocks would have a main continental source from Archean rocks. Rhodochrosite is restricted and diagenetic, likely pyrite. Tectonic deformations reached the whole package and provided environment and structures for remobilization and reprecipitation of Mn-oxyhydroxides of high content and crystallinity. These two types of ores were the source of lateritic ore and colluvionary, already practically depleted
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4

Wang, Wenming, Zongze Shao, Yanjun Liu, and Gejiao Wang. "Removal of multi-heavy metals using biogenic manganese oxides generated by a deep-sea sedimentary bacterium – Brachybacterium sp. strain Mn32." Microbiology 155, no. 6 (June 1, 2009): 1989–96. http://dx.doi.org/10.1099/mic.0.024141-0.

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A deep-sea manganese-oxidizing bacterium, Brachybacterium sp. strain Mn32, showed high Mn(II) resistance (MIC 55 mM) and Mn(II)-oxidizing/removing abilities. Strain Mn32 removed Mn(II) by two pathways: (1) oxidizing soluble Mn(II) to insoluble biogenic Mn oxides – birnessite (δ-MnO2 group) and manganite (γ-MnOOH); (2) the biogenic Mn oxides further adsorb more Mn(II) from the culture. The generated biogenic Mn oxides surround the cell surfaces of strain Mn32 and provide a high capacity to adsorb Zn(II) and Ni(II). Mn(II) oxidation by strain Mn32 was inhibited by both sodium azide and o-phenanthroline, suggesting the involvement of a metalloenzyme which was induced by Mn(II). X-ray diffraction analysis showed that the crystal structures of the biogenic Mn oxides were different from those of commercial pyrolusite (β-MnO2 group) and fresh chemically synthesized vernadite (δ-MnO2 group). The biogenic Mn oxides generated by strain Mn32 showed two to three times higher Zn(II) and Ni(II) adsorption abilities than commercial and fresh synthetic MnO2. The crystal structure and the biogenic MnO2 types may be important factors for the high heavy metal adsorption ability of strain Mn32. This study provides potential applications of a new marine Mn(II)-oxidizing bacterium in heavy metal bioremediation and increases our basic knowledge of microbial manganese oxidation mechanisms.
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5

Gao, Lingfeng, Shan Xu, Xiangyun Hu, Shuang Liu, Qi Zhou, and Bingnan Yang. "Sedimentary Setting and Ore-Forming Model in the Songtao Manganese Deposit, Southwestern China: Evidence from Audio-Frequency Magnetotelluric and Gravity Data." Minerals 11, no. 11 (November 17, 2021): 1273. http://dx.doi.org/10.3390/min11111273.

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The break-up of the supercontinent Rodinia in the late Neoproterozoic led to the formation of the Nanhua rift basin within the South China Block. The Datangpo-type manganese deposit, which developed in the Nanhua rift basin, is one of the most important types of manganese deposits in South China. Although it is widely accepted that deep sedimentary structures significantly affect the manganese ore system, the relationship between the manganese deposits in South China and the Nanhua rifting process is still unclear. The origin of the manganese ore layer remains controversial. In this paper, we integrated the audio-frequency magnetotelluric (AMT) data, gravity data, and comprehensive geological and borehole data analysis to characterize the structure of the Datangpo-type manganese deposit in Songtao, Guizhou Province. The resistivity and density models produced an inclined layered structure, which correlated well with the coeval sediment strata of the Nanhua rift basin. A high-resistivity cap was observed from the surface to a depth of 800 m, corresponding to the Cambrian Loushanguan (ϵ3−4ls) and Palang dolomite formation (ϵ2p), which has helped the storage of the manganese ore. The most significant low-resistivity anomaly (25–40 Ω·m) resides at a depth of 1400 m in the Nantuo (Nh3n) gravel sandstone and Datangpo (Nh2d) silty and carbonaceous shale, corresponding to the ore-forming layer. This distinct low-resistivity layer was possibly produced by aqueous fluids and pyrite in the syn-sedimentary fault and alteration zone. The accumulations of sulfide minerals in the rock samples suggest a possible anoxic-euxinic deposition environment during the manganese mineralization and precipitation. The fault revealed in the resistivity models is perhaps a previous fault zone produced by extension in the Nanhua rifting process, which provided migration and upwelling channels for ore-forming minerals. Based on our resistivity models, density models, and geological survey, the manganese ore-forming model was derived, which can help to provide geophysical evidence for the origin of the Datangpo-type manganese deposit.
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6

Pattan, J. N. "Manganese micronodules: A possible indicator of sedimentary environments." Marine Geology 113, no. 3-4 (August 1993): 331–44. http://dx.doi.org/10.1016/0025-3227(93)90026-r.

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7

Johnson, Jena E., Samuel M. Webb, Chi Ma, and Woodward W. Fischer. "Manganese mineralogy and diagenesis in the sedimentary rock record." Geochimica et Cosmochimica Acta 173 (January 2016): 210–31. http://dx.doi.org/10.1016/j.gca.2015.10.027.

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8

Michel, Magdalena. "A study of application of chalcedonite as a manganese dioxide carrier." Annals of Warsaw University of Life Sciences - SGGW. Land Reclamation 44, no. 1 (January 1, 2012): 63–73. http://dx.doi.org/10.2478/v10060-011-0063-z.

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A study of application of chalcedonite as a manganese dioxide carrier Chalcedonite is a sedimentary siliceous rock, which occurs at four deposits in Poland and is included into a group of unique rocks. Chalcedonite is utilized in water treatment technology, mostly as an effective filtration material due to its mesoporous structure and extended outer surface of the grains. This paper presents three different methods of impregnation of the mineral material (MDMC-1, MDMC-2, MDMC-3) by manganese dioxide. As an oxide carrier chalcedonite was used. The results of the chalcedonite surface modification with SEM-EDS technique were presented. It was found that the chalcedonite is a very good manganese dioxide carrier and the modification of the chalcedonite surface changes its chemical composition, structure and value of the specific surface area.
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9

Xu, Zhiming, Chengquan Wu, Zhengwei Zhang, Jinhong Xu, Xiyao Li, and Ziru Jin. "Separation of Fe from Mn in the Cryogenian Sedimentary Mn Deposit, South China: Insights from Ore Mineral Chemistry and S Isotopes from the Dawu Deposit." Minerals 11, no. 5 (April 23, 2021): 446. http://dx.doi.org/10.3390/min11050446.

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Manganese and Fe have similar geochemical properties in the supergene environment. Separation of Mn and Fe is an important process for the formation of high-grade sedimentary manganese deposits. Large-scale manganese carbonate deposits (total reserves of approximately 700 Mt) were formed during the interglacial of the Sturtian and Marinoan in South China. The orebodies are hosted in the black rock series at the basal Datangpo Formation of the Cryogenian period. The Fe contents in ores range from 1.15 to 7.18 wt.%, with an average of 2.80 wt.%, and the average Mn/Fe ratio is 8.9, indicating a complete separation of Mn and Fe during the formation of manganese ores. Here, we present element data of manganese carbonates and sulfur isotopes of pyrite from the Dawu deposit, Guizhou, China, aiming to investigate the separation mechanism of Mn and Fe and the ore genesis. The Fe in ores mainly occurs as carbonate (FeCO3) and pyrite (FeS2). The Mn, Ca, Mg and Fe exist in the form of isomorphic substitutions in manganese carbonate. The contents of FeCO3 in manganese carbonates are similar in different deposits, with averages of 2.6–2.8 wt.%. The whole-rock Fe and S contents have an obvious positive correlation (R = 0.69), indicating that the difference of whole-rock Fe content mainly comes from the pyrite content. The δ34SV-CDT of pyrite varies from 40.0 to 48.3‰, indicating that the pyrite formed in a restricted basin where sulfate supply was insufficient and the sulfate concentrations were extremely low. Additionally, the whole-rock Fe content is negatively correlated with the δ34S values of the whole-rock and pyrite, with correlation coefficients of −0.78 and −0.83, respectively. Two stages of separations of Mn and Fe might have occurred during the mineralization processes. The reduced seawater became oxidized gradually after the Sturtian glaciation, and Fe2+ was oxidized and precipitated before Mn2+, which resulted in the first-stage separation of Mn and Fe. The residual Mn-rich and Fe-poor seawater flowed into the restricted rift basin. Mn and Fe were then precipitated in sediments as oxyhydroxide as the seawater was oxidized. At the early stage of diagenesis, organic matter was oxidized, and manganese oxyhydroxide was reduced, forming the manganese carbonate. H2S was insufficient in the restricted basin due to the extremely low sulfate concentration. The Fe2+ was re-released due to the lack of H2S, resulting in the second-stage separation of Mn and Fe. Finally, the manganese carbonate deposit with low Fe and very high δ34S was formed in the restricted basin after the Sturtian glaciation.
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10

Ostwald, J., and Barrie R. Bolton. "Glauconite formation as a factor in sedimentary manganese deposit genesis." Economic Geology 87, no. 5 (August 1, 1992): 1336–44. http://dx.doi.org/10.2113/gsecongeo.87.5.1336.

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11

Sugisaki, Ryuichi, Kenichiro Sugitani, and Mamoru Adachi. "Manganese Carbonate Bands as an Indicator of Hemipelagic Sedimentary Environments." Journal of Geology 99, no. 1 (January 1991): 23–40. http://dx.doi.org/10.1086/629471.

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12

Gutzmer, J., and N. J. Beukes. "Fault-controlled metasomatic alteration of early Proterozoic sedimentary manganese ores in the Kalahari manganese field, South Africa." Economic Geology 90, no. 4 (July 1, 1995): 823–44. http://dx.doi.org/10.2113/gsecongeo.90.4.823.

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13

Gutzmer, J., A. P. Du Plooy, and N. J. Beukes. "Timing of supergene enrichment of low-grade sedimentary manganese ores in the Kalahari Manganese Field, South Africa." Ore Geology Reviews 47 (September 2012): 136–53. http://dx.doi.org/10.1016/j.oregeorev.2012.04.003.

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14

Glasby, G. P. "Fractionation of manganese from iron in Archaean and Proterozoic sedimentary ores." Geological Society, London, Special Publications 119, no. 1 (1997): 29–42. http://dx.doi.org/10.1144/gsl.sp.1997.119.01.03.

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15

Xie, Jiancheng, Xiaoyong Yang, Jianguo Du, and Wei Xu. "Geochemical Characteristics of Sedimentary Manganese Deposit of Guichi, Anhui Province, China." Journal of Rare Earths 24, no. 3 (June 2006): 374–80. http://dx.doi.org/10.1016/s1002-0721(06)60127-0.

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16

Baohong Hou. "Primary braunite in Triassic sedimentary manganese deposits of Dounan, Yunnan, China." Ore Geology Reviews 9, no. 3 (August 1994): 219–39. http://dx.doi.org/10.1016/0169-1368(94)90007-8.

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17

Sugisaki, Ryuichi, Masayoshi Ohashi, Kenichiro Sugitani, and Kazuhiro Suzuki. "Compositional Variations in Manganese Micronodules: A Possible Indicator of Sedimentary Environments." Journal of Geology 95, no. 4 (July 1987): 433–54. http://dx.doi.org/10.1086/629142.

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18

Latif, Dnya Abdualwahab, Yousif Osman Mohammad, and Musher Mustafa Baziani. "Mineralogy and Origin of the Manganese Deposit in the Sulaimani Province, Kurdistan Region of Iraq: Insight to Serpentinization-Induced Manganese Production Scenario." Iraqi Geological Journal 55, no. 1F (June 30, 2022): 178–200. http://dx.doi.org/10.46717/igj.55.1f.15ms-2022-06-30.

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The Manganese deposits in Sulaimani metallogenic province mainly occur within the top Qulqula Radiolarite chert unit of the Penjween ophiolite complex as strata bound type deposits near Kani Saif village, 15 km south of the Penjween district within the Imbricated zone, Kurdistan Region of Iraq. A restricted occurrence of massive manganese boulders was identified, 1 km north to the Mawat District, associated with the Oligocene Merga Red beds Group. The Qulqula Radiolarite represents the Middle Jurassic-Early Cretaceous sedimentary cover of Neo-Tethys oceanic crust deposits throughout the early to mature stages of the Neo-Tethys ocean opening along the northern and eastern margins of the Afro-Arabian plate. The field and petrographical data indicated that the nature of manganese mineralization in the area is of various forms including veins, brecciated, micronodules, banded and massive types. Reflected light microscopy, high resolution scanning electron microscope and X-ray diffraction reveal that the mineral assemblages are dominated by barunite, rhodinite, hematite, quartz and carbonate for the massive metamorphosed type deposit in the Mawat area. Meanwhile, the mineralogy of the vein, micronodule and banded types are simple and dominated by pyrolusite, hollandite minerals close to Kain Saif village. Combinations of the modal manganese minerals, filed and textural observations, a paragenetic-time model suggests that the manganese deposit in the area formed via a sequence of multiple processes (1) serpentinization of the upper mantle at mid oceanic ridge during the Cretaceous period, (2) deposition from diluted hydrothermal fluids in the Neo-Tethys mature oceanic basin, (3) the diagenetic modification of the manganese bearing sediment and (4) metamorphism of sediment a combing Zagros orogeny in Paleogene. Overall data suggest that the manganese deposits in the Kurdistan region of Iraq are cogenetic and spatially related to those which occur along the entire margin of the Arabian plates from Oman to Turkey associated with the radiolarite facies.
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19

El-Shafei, Shaimaa, Fatma Ramadan, Mohamed Essawy, Ahmed Henaish, and Bassem Nabawy. "Geology, mineralogy and geochemistry of manganese ore deposits of the Um Bogma Formation, south-western Sinai, Egypt: genesis implications." Mining of Mineral Deposits 16, no. 3 (September 30, 2022): 86–95. http://dx.doi.org/10.33271/mining16.03.086.

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Purpose.This paper aims to understand the genesis and nature of the manganese ore deposits associated with the Ras Samra Member of the Um Bogma Formation in the southwest of Sinai. Methods. Mineralogical and geochemical studies of 50 selected samples of manganese ores and host shale have been conducted. These samples have been taken from different sites representing the Ras Samra Member. Findings. The dominant manganese minerals are pyrolusite and hausmannite. In most samples, helvite and hematite are noted in association with pyrolusite. In the investigated manganese ores, wide ranges of MnO (17.70-81.90 wt. %) and Fe2O3 (1.16-65.49 wt. %) concentrations are observed. Based on their Mn/Fe ratio, they can be classified into high-Mn ore content (76.94-6.46%), medium-Mn ore content (4.87-2.58%), and low-Mn ore content (1.51-0.30%). Originality. The compositions of major and trace elements in Ras Samra manganese ores, together with their textures and mineralogical compositions, suggest an epigenetic hydrothermal contribution for high-Mn ores, as well as syngenetic sedimentary precipitation for medium- Mn and low-Mn ores. The epigenetic nature of the high-Mn samples may be related to a younger phase of hydrothermal activity associated with Tertiary basalt flows. Ore-bearing hypogene solutions, which penetrate the bedding planes, have impregnated and cemented non-diagenetic terrigenous sandstones and shale. Practical implications. In contrast to low-Mn ores, high-Mn and medium-Mn ores of Um Bogma are preferable for obtai-ning a significant economic effect in the production of ferromanganese alloys. However, low-Mn ores need to be processed appropriately to achieve the desired quality in order to meet the present level of manganese demand in Egypt.
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20

Ostwald, J., and B. R. Bolton. "Diagenetic braunite in sedimentary rocks of the proterozoic Manganese Group, Western Australia." Ore Geology Reviews 5, no. 4 (May 1990): 315–23. http://dx.doi.org/10.1016/0169-1368(90)90036-m.

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21

Roy, Supriya. "Sedimentary manganese metallogenesis in response to the evolution of the Earth system." Earth-Science Reviews 77, no. 4 (August 2006): 273–305. http://dx.doi.org/10.1016/j.earscirev.2006.03.004.

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22

Bayirli, Mehmet. "Numerical Approaches of Cluster Statistics for Stochastic Manganese Deposits." Zeitschrift für Naturforschung A 69, no. 10-11 (November 1, 2014): 581–88. http://dx.doi.org/10.5560/zna.2014-0054.

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AbstractIn terms of origin, the most important manganese deposits are sedimentary deposits which grow on the surface and/or fractures of the natural magnesite ore. They reveal various morphological characteristic according to their location in origin. Some of them may be fractal in appearance. Although several studies have been completed with regards to their growth mechanism, it may be safe to say that their cluster statistics and scaling properties have rarely been subject an academic scrutiny. Hence, the subject of this study has been designed to calculate cluster statistics of manganese deposits by first; transferring the images of manganese deposits into a computer and then scaling them with the help of software. Secondly, the root-mean square (rms) thickness (also called as expected value in systems), the number of particles, clusters and cluster sizes are computed by means of scaling method. In doing so it has been found that the rms thickness and the number of particles are in correlation, a result which is called as power-law behaviour, T~N-ε (the critical exponent is computed as ε = 1.743). It has also been found that the correlation between the number of clusters and their sizes are determined with the power-law behaviour n(s)~s-τ (the critical exponent t may vary between 1.054 and 1.321). Finally, the distribution functions of natural manganese clusters on the magnesite subtract have been determined. All that may point to the fact that the manganese deposits may be formed according to a Poisson distribution. The results found and the conclusion reached in this study may be used to compare various natural deposits in geophysics.
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23

Herrera, N., and N. Toro. "Use of tailings in mn dissolution from marine nodule matrix." E3S Web of Conferences 266 (2021): 02008. http://dx.doi.org/10.1051/e3sconf/202126602008.

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The nodules are spherical bodies that are scattered within the sedimentary zone of the seabed, and their growth is closely associated with the biogeochemical processes and water sediments. These nodules are mainly composed of Mn, Fe, SiO2, Ca, Ni, Cu, Co and Al. Manganese nodules are an excellent source of base metals and sought-after and rare elements and the fact that they are used as a base elements matrix will be in high demand in industry. Previous studies have shown that primary con-centrations of chemical such as Fe in the system are beneficial for increas-ing manganese extraction. However, it is necessary to optimize the opera-tional parameters so as to maximise Mn recovery. This work investigates the effect of using of tailings, obtained after slag flotation ata foundry plant on the dissolution of Mn from marine nodules, where statistical analysis was distributed using factorial experimental design ontime, MnO2/Fe2O3 ratio, and H2SO4 concentration.
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24

Adamu, L. M., N. G. Obaje, A. A. Sidi, A. K. Aweda, and H. M. Liman. "Geochemical Evidence for the Origin of the Daranna Manganese Deposit, Kebbi State, Nigeria." Nigerian Journal of Basic and Applied Sciences 29, no. 2 (February 8, 2022): 30–45. http://dx.doi.org/10.4314/njbas.v29i2.4.

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Inorganic and organic geochemical and geostatistical studies of manganese ore deposits exposed at Daranna, near Kaoje have been carried out with the aim of characterizing and delineating the origin of the manganese ore deposits. Data were obtained from field observations and chemical analyses of 12 ore samples. Major and trace elements and organic geochemical analyses were conducted with Energy Dispersion X-ray Fluorescence Spectrometer and Rock-Eval pyrolysis method at Geo-data GmbH Garbsen, Germany. Results of the Major and trace elements, total organic carbon content abundances and the correlation among them imply that Daranna mineralizations are mainly of hydrothermal origin with little contribution from contemporaneous volcanic materials and this is confirmed by high Fe/Mn (8.274 to 24.066 wt%) and low Co/Zn ratios and trace element patterns. The significant geochemical characteristics such as high Mn content (22.660 to 62.330 wt%; average 45.919 wt%), low concentration of Fe (2.590 to 3.310 wt%; average 3.008 wt%) reveal a primary distal hydrothermal source for mineralization. The position of samples on Ni–Zn–Co and (Co/Zn)–(Co + Ni + Cu) diagrams and evaluation of these data reveals that hydrothermal activity was the main process with sedimentary influence responsible for mineralization in the Daranna manganese deposit.
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25

Jones, C., S. A. Crowe, A. Sturm, K. L. Leslie, L. C. W. MacLean, S. Katsev, C. Henny, D. A. Fowle, and D. E. Canfield. "Biogeochemistry of manganese in ferruginous Lake Matano, Indonesia." Biogeosciences 8, no. 10 (October 26, 2011): 2977–91. http://dx.doi.org/10.5194/bg-8-2977-2011.

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Abstract. This study explores Mn biogeochemistry in a stratified, ferruginous lake, a modern analogue to ferruginous oceans. Intense Mn cycling occurs in the chemocline where Mn is recycled at least 15 times before sedimentation. The product of biologically catalyzed Mn oxidation in Lake Matano is birnessite. Although there is evidence for abiotic Mn reduction with Fe(II), Mn reduction likely occurs through a variety of pathways. The flux of Fe(II) is insufficient to balance the reduction of Mn at 125 m depth in the water column, and Mn reduction could be a significant contributor to CH4 oxidation. By combining results from synchrotron-based X-ray fluorescence and X-ray spectroscopy, extractions of sinking particles, and reaction transport modeling, we find the kinetics of Mn reduction in the lake's reducing waters are sufficiently rapid to preclude the deposition of Mn oxides from the water column to the sediments underlying ferruginous water. This has strong implications for the interpretation of the sedimentary Mn record.
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26

Schissel, Don, and Phil Aro. "The major early Proterozoic sedimentary iron and manganese deposits and their tectonic setting." Economic Geology 87, no. 5 (August 1, 1992): 1367–74. http://dx.doi.org/10.2113/gsecongeo.87.5.1367.

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27

Scholtysik, Grzegorz, Tobias Goldhammer, Helge W. Arz, Matthias Moros, Ralf Littke, and Michael Hupfer. "Geochemical focusing and burial of sedimentary iron, manganese, and phosphorus during lake eutrophication." Limnology and Oceanography 67, no. 4 (February 28, 2022): 768–83. http://dx.doi.org/10.1002/lno.12019.

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28

Jordan, P., and B. Rippey. "Lake sedimentary evidence of phosphorus, iron and manganese mobilisation from intensively fertilised soils." Water Research 37, no. 6 (March 2003): 1426–32. http://dx.doi.org/10.1016/s0043-1354(02)00488-8.

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29

Mukhopadhyay, Joydip, Jens Gutzmer, and Nicolas J. Beukes. "Organotemplate structures in sedimentary manganese carbonates of the Neoproterozoic Penganga Group, Adilabad, India." Journal of Earth System Science 114, no. 3 (June 2005): 247–57. http://dx.doi.org/10.1007/bf02702948.

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30

Flohr, Marta J. K., and J. Stephen Huebner. "Mineralogy and geochemistry of two metamorphosed sedimentary manganese deposits, Sierra Nevada, California, USA." Lithos 29, no. 1-2 (December 1992): 57–85. http://dx.doi.org/10.1016/0024-4937(92)90034-v.

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31

Madison, Andrew S., Bradley M. Tebo, Alfonso Mucci, Bjørn Sundby, and George W. Luther. "Abundant Porewater Mn(III) Is a Major Component of the Sedimentary Redox System." Science 341, no. 6148 (August 22, 2013): 875–78. http://dx.doi.org/10.1126/science.1241396.

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Soluble manganese(III) [Mn(III)] can potentially serve as both oxidant and reductant in one-electron-transfer reactions with other redox species. In near-surface sediment porewater, it is often overlooked as a major component of Mn cycling. Applying a spectrophotometric kinetic method to hemipelagic sediments from the Laurentian Trough (Quebec, Canada), we found that soluble Mn(III), likely stabilized by organic or inorganic ligands, accounts for up to 90% of the total dissolved Mn pool. Vertical profiles of dissolved oxygen and dissolved and solid Mn suggest that soluble Mn(III) is primarily produced via oxidation of Mn(II) diffusing upwards from anoxic sediments with lesser contributions from biotic and abiotic reductive dissolution of MnO2. The conceptual model of the sedimentary redox cycle should therefore explicitly include dissolved Mn(III).
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32

Scholtysik, Grzegorz, Olaf Dellwig, Patricia Roeser, Helge Wolfgang Arz, Peter Casper, Christiane Herzog, Tobias Goldhammer, and Michael Hupfer. "Geochemical focusing and sequestration of manganese during eutrophication of Lake Stechlin (NE Germany)." Biogeochemistry 151, no. 2-3 (November 24, 2020): 313–34. http://dx.doi.org/10.1007/s10533-020-00729-9.

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AbstractSignificant sedimentation of manganese (Mn) in form of manganese oxides (MnOx) and the subsequent formation of authigenic calcium-rich rhodochrosite (Mn(Ca)CO3) were observed in the seasonally stratified hard water Lake Stechlin in north-eastern Germany. This manganese enrichment was assumed to be associated with recent eutrophication of the formerly oligotrophic lake. The mechanisms and processes involved were examined by analysing: (i) short sediment cores obtained from seven locations along a depth transect ranging from 69.5 m (the deepest point) to 38 m; (ii) sediment traps located at 20 m and 60 m water depths; (iii) water column profiles; and (iv) porewater profiles at 69.5 m and 58 m depths. Sedimentary Mn enrichment was observed at water depths below 56 m and increased to more than 25 wt% at the deepest site. Between 2010 and 2017, Mn accumulation at the deepest site was 815 g Mn m−2. Transfer of Mn from the shallower towards the deepest parts of the lake was initiated by reductive dissolution of MnOx and diffusion of dissolved Mn from the sediment to the overlying water column. Manganese was then dissipated via turbulent mixing and subsequently oxidised to MnOx before being transported towards the deepest zone. Transformation of the redeposited MnOx to Mn(Ca)CO3 favoured the final burial of Mn. We show that eutrophication and the areal spreading of anoxic conditions may intensify diagenetic processes and cause the spatial redistribution of Mn as well as its effective burial. Contrary to many previous findings, we show that increases of Mn and Mn/Fe can also be used as indicators for increasing anoxic conditions in previously oligotrophic lakes.
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Jones, C., S. A. Crowe, A. Sturm, K. L. Leslie, L. C. W. MacLean, S. Katsev, C. Henny, D. A. Fowle, and D. E. Canfield. "Biogeochemistry of manganese in Lake Matano, Indonesia." Biogeosciences Discussions 8, no. 2 (April 26, 2011): 4063–106. http://dx.doi.org/10.5194/bgd-8-4063-2011.

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Abstract. This study explores Mn biogeochemistry in a stratified, ferruginous lake. Intense Mn cycling occurs in the chemocline where Mn is recycled at least 15 times before sedimentation. The kinetics of Mn oxidation in Lake Matano are similar to other studied environments, implying that Mn oxidation is relatively insensitive to environmental parameters and may be controlled by similar mechanisms in diverse settings. The product of biologically catalyzed Mn oxidation in Lake Matano is birnessite. Although there is evidence for abiotic Mn reduction with Fe(II), Mn reduction likely occurs through a variety of pathways. The flux of Fe(II) is insufficient to balance the reduction of Mn at 125 m depth in the water column, and Mn reduction could be a significant contributor to CH4 oxidation. By combining results from synchrotron-based X-ray fluorescence and X-ray spectroscopy, extractions of sinking particles, and reaction transport modeling, we find the kinetics of Mn reduction in the lake's reducing waters are sufficiently rapid to preclude the deposition of Mn oxides from the water column to the sediments underlying anoxic water. Rather, Mn is likely sequestered in these sediments as pseudo kutnahorite. This has strong implications for the interpretation of the sedimentary Mn record.
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34

Zhang, Zhen Guo, Chang Shui Liu, Lian Feng Gao, Ying Zhang, Guo Yuan Shi, and Peng Zhang. "Causative Mechanism of the Continental Margin Polymetallic Nodules from the South China Sea and its Resource Effects." Advanced Materials Research 524-527 (May 2012): 408–12. http://dx.doi.org/10.4028/www.scientific.net/amr.524-527.408.

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Polymetallic nodules are one of the most important sedimentary mineral resources in the ocean, in which iron, manganese, copper, cobalt, nickel and other metals are rich, and rare earth elements are rich, too. The samples are collected from the northwest continental margin of South China Sea (SCS). Their model show the similar appearance to the oceanic nodules which collected from the Pacific and Indian Ocean. They are big, regular shape and clear layers. But their geochemical characteristics show distinct difference with oceanic nodules.The samples formed by multiple millimeter-thick layers of Fe and Mn oxyhydroxides surrounding the nucleus composed of plastic marl and sediment. Massive, laminated, detrital and mottled to dendritic textural features were developed by the Fe and Mn oxyhydroxide layers.Based on the detailed study of the geochemistry and growth rate, the nodules may represent new-type ones which grow fastly in high sediment rates environment from the northwest continental margin of the SCS. The reason of the fast growth may be affected by the environmental fluctuations and the change of terrigenous sediments. Elements correlation of Mn-Fe-(Cu+Ni) suggests that the origin of the sample may be of hydrogenic. It may be show that these nodules are dominative of the special environment of the marginal sea which includes the geographical condition and the oceanic environmental factors. The average content of Rare Earth Elements (REEs) in these samples are much higher than those recorded in Earth’ crust and sedimentary rocks. The enrichment of rare earth elements is controlled by iron and manganese oxides and clay minerals in nodules, which could absorb rare earth elements from seawater and terrigenous sediment. Ce elements are highly enriched, making polymetallic nodules become the first used rare earth elements in oceanic mineral development.
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Calvert, S. E., and T. F. Pedersen. "Sedimentary geochemistry of manganese; implications for the environment of formation of manganiferous black shales." Economic Geology 91, no. 1 (February 1, 1996): 36–47. http://dx.doi.org/10.2113/gsecongeo.91.1.36.

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36

Slomp, C. P., J. F. P. Malschaert, L. Lohse, and W. Van Raaphorst. "Iron and manganese cycling in different sedimentary environments on the North Sea continental margin." Continental Shelf Research 17, no. 9 (August 1997): 1083–117. http://dx.doi.org/10.1016/s0278-4343(97)00005-8.

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37

Martin-Barajas, A., E. Lallier-Verges, and L. Leclaire. "Characteristics of manganese nodules from the Central Indian Basin: Relationship with the sedimentary environment." Marine Geology 101, no. 1-4 (October 1991): 249–65. http://dx.doi.org/10.1016/0025-3227(91)90074-e.

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38

Askarova, N. S., V. S. Portnov, G. G. Blyalova, R. K. Madisheva, and V. V. Dyakonov. "Geology and minerageny of the Bestobe deposit (Central Kazakhstan)." Kompleksnoe Ispolʹzovanie Mineralʹnogo syrʹâ/Complex Use of Mineral Resources/Mineraldik Shikisattardy Keshendi Paidalanu 321, no. 2 (March 2, 2022): 22–30. http://dx.doi.org/10.31643/2022/6445.14.

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Polygenic stratiform deposits are the largest in the world in terms of barite and manganese reserves, as well as lead and zinc reserves. In the mineral resource complex of the Republic of Kazakhstan, they are of great importance and are distinguished as an independent genetic Atasu type. In the article, the deposits of the Zhailma graben-syncline in a large riftogenic structure are considered as a reference for the Atasu type. The geological structure of the Bestobe stratiform polymetallic deposit located in the eastern part of the Zhailma synclinorium is presented. The stratigraphy of ore formations, mineralization features, morphology of the ore body and the pattern of zoning the distribution of elements in the ore-bearing rocks of the Bestobe deposit are shown. A feature of the deposit is the combination of layered iron-manganese and lead-zinc ores and superimposed zinc-lead-barite mineralization; the sharply subordinate role of hydrothermal-sedimentary ores in the total reserves of lead and zinc; comparative abundance of lead, copper and silver sulfosalts. The analysis of the materials indicates that mineralization at the Bestobe deposit is complex. Its main value is polymetallic ores. The role of iron ore mineralization of the deposit is insignificant. Manganese mineralization is practically absent. Polymetallic ores are conventionally subdivided into lead-zinc-barite, lead-barite, barite and lead-zinc. Strontium is a constant impurity in barites. Lead is mainly concentrated in galena; its insignificant amount is found in geocronite, boulangerite, jamsonite, bournonite, cerussite, anglesite, pyromorphite, plumboyarosite. The bulk of zinc is concentrated in the form of sphalerite.
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39

McSwiggen, Peter L., G. B. Morey, and Jane M. Cleland. "Occurrence and genetic implications of hyalophane in manganese-rich iron-formation, Cuyuna Iron Range, Minnesota, USA." Mineralogical Magazine 58, no. 392 (September 1994): 387–99. http://dx.doi.org/10.1180/minmag.1994.058.392.04.

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AbstractThe recent discovery of hyalophane [(K,Ba)Al1−2Si3−2O8] on the North range segment of the Early Proterozoic Cuyuna Iron Range of east-central Minnesota has shed new light on the depositional environment of these rocks. This Ba-feldspar occurs in a 10 m thick interval within the main iron-formation and typically contains between 8 and 26 mol.% celsian (BaAl2Si2O8). Its occurrence in several textural settings suggests that barium was being deposited at various stages in the paragenetic history of the iron-formation. Some of the hyalophane grains occur as the cores of micronodules, which are structurally similar to oolites or oncolites, but mineralogically are very complex. The hyalophane also occurs as rims on core grains of diverse mineral composition and as discrete phases in late crosscutting veins.Hyalophane, like other Ba-silicates, has a very restricted paragenesis. They are associated typically either with sedimentary manganese and ferromanganese deposits, or with Cu-Pb-Zn-Ba deposits. The presence of hyalophane in the Early Proterozoic manganiferous iron ores of east-central Minnesota casts doubt on the historic interpretation of these deposits as typical Superior-type sedimentary iron-formations and instead supports the view that these deposits, at least in part, consist of chemical sediments from a hydrothermal fumarolic system. The suggested involvement of a hydrothermal system is also supported by the occurrence of aegirine within the hyalophane-rich layer, and the occurrence of tourmalinites and Sr-rich baryte veins elsewhere in the Cuyuna North range.
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40

Robbins, Eleanora, Shannon Quigley-Raymond, Ming Lai, and Janae Fried. "Microbial Geochemistry Reflecting Sulfur, Iron, Manganese, and Calcium Sources in the San Diego River Watershed, Southern California USA." Geosciences 8, no. 12 (December 17, 2018): 495. http://dx.doi.org/10.3390/geosciences8120495.

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Microbial populations involved in forming the distinctive precipitates of S, Fe, Mn, and Ca in the San Diego River watershed reflect an interplay between the mineralogy of the rocks in the watershed, sparse rainfall, ground- and surface-water anoxia, and runoff of high sulfate, treated imported water. In the sparsely developed headwaters, the Temescal Creek tributary emerges from pyrite-bearing metamorphic rocks, and thus exhibits both an oxidized Fe and reduced S. In the middle reaches, the river moves through developed land where treated, imported high sulfate Colorado River water enters from urban runoff. Mast Park surrounded by caliche-bearing sedimentary rocks is a site where marl is precipitating. Cobbles in riffles along the river are coated black with Mn oxide. When the river encounters deep-seated volcanic bedrock, it wells up to precipitate both Fe and Mn oxides at the Old Mission Dam. Then, directly flowing through caliche-laced sedimentary rocks, Birchcreek tributary precipitates tufa. Further downstream at a site under a bridge that blocks sunlight, a sulfuretum sets up when the river is deoxygenated. Such a rich geochemistry results in activity of iron and manganese oxidizing bacteria, sulfur oxidizers and reducers, and cyanobacteria precipitating calcareous marl and tufa.
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41

D'Hondt, S., F. Inagaki, and C. Alvarez Zarikian. "IODP Expedition 329: Life and Habitability Beneath the Seafloor of the South Pacific Gyre." Scientific Drilling 15 (March 1, 2013): 4–10. http://dx.doi.org/10.5194/sd-15-4-2013.

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Integrated Ocean Drilling Program (IODP) Expedition 329 made major strides toward fulfilling its objectives. Shipboard studies documented (1) fundamental aspects of habitability and life in this very low activity subseafloor sedimentary ecosystem and (2) first-order patterns of habitability within the igneous basement. A broad range of postexpedition studies will complete the expedition objectives. Throughout the South Pacific Gyre (SPG; Sites U1365–U1370), dissolved oxygen and nitrate are present throughout the entire sediment sequence, and sedimentary microbial cell counts are lower than at all previously drilled IODP/ Ocean Drilling Program (ODP)/Deep Sea Drilling Program (DSDP) sites. In contrast, at Site U1371 in the upwelling zone just south of the gyre, detectable oxygen and nitrate are limited to the top and bottom of the sediment column, manganese reduction is a prominent electron-accepting process, and cell concentrations are higher than at the same depths in the SPG sites throughout the sediment column. Geographic variation in subseafloor profiles of dissolved and solid-phase chemicals are consistent with the magnitude of organic-fueled subseafloor respiration declining from outside the gyre to the gyre center. <br><br> Chemical profiles in the sedimentary pore water and secondary mineral distributions in the basaltic basement indicate that basement alteration continues on the timescale of formation fluid replacement, even at the sites with the oldest basement (84–120 Ma at Sites U1365 and U1366). <br><br> doi:<a href="http://dx.doi.org/10.2204/iodp.sd.15.01.2013" target="_blank">10.2204/iodp.sd.15.01.2013</a>
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42

SUGITANI, Kenichiro. "A geochemical study of hydrothermal manganese micronodules from marine sediments and sedimentary rocks on land." Journal of the Geological Society of Japan 93, no. 8 (1987): 555–74. http://dx.doi.org/10.5575/geosoc.93.555.

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43

Algouti, Ahmed, Abdellah Algouti, Fatiha Hadach, and Naji Jdaba. "Geodynamic of the Cenomanian-Turonian Sedimentary Basin and the Manganese Mineralization Setting (Imini-Boutazoult, Morocco)." Iraqi Geological Journal 55, no. 2D (October 31, 2022): 83–107. http://dx.doi.org/10.46717/igj.55.2d.8ms-2022-10-24.

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The Upper Cenomanian-Lower Turonian of the Imini-Boutazoult region consists of a limestone containing Mn mineralization-rich beds. In order to demonstrate the relation between the mineralization and the sedimentary context, this study was carried out to analyze the evolution of the paleoenvironments during this interval. In the field, the boundaries that allowed the lithostratigraphic division are continuous and are easily recognizable from one section to another, which contributed to simplifying the subdivisions of the Cenomanian-Turonian lithostratigraphy into three units U1, U2 and U3. All the geological data from the field and the sequential, sedimentological and diagenetic analyses made it possible to elaborate correlative diagrams showing the spatio-temporal evolution as well as paleogeographical sketches during the dolomitic deposits of the Cenomanian-Turonian. The Mn mineralization may be linked to the diagenesis in the vadose zone in a very shallow internal platform. It can also be very belated and strongly linked to karstification with areas supporting the circulation of fresh water (dissolution cavities, dissolved fossils, cracks, fractures.
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44

Gutzmer, J., and N. J. Beukes. "Effects of mass transfer, compaction and secondary porosity on hydrothermal upgrading of Paleoproterozoic sedimentary manganese ore in the Kalahari manganese field, South Africa." Mineralium Deposita 32, no. 3 (May 26, 1997): 250–56. http://dx.doi.org/10.1007/s001260050090.

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45

Johnson, J. E., S. M. Webb, C. B. Condit, N. J. Beukes, and W. W. Fischer. "Effects of metamorphism and metasomatism on manganese mineralogy: Examples from the Transvaal Supergroup." South African Journal of Geology 122, no. 4 (December 1, 2019): 489–504. http://dx.doi.org/10.25131/sajg.122.0034.

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AbstractManganese-bearing minerals in ancient strata provide a particularly informative record of the redox potentials of ancient Earth surface environments due to the high specificity of species that can oxidize Mn(II). However, little is known about how this sedimentary archive might have been altered by processes occurring long after lithification, including the effects of metamorphism, fluid mobilization, and metasomatism. We investigated Mn mineralization across known metamorphic gradients in the Kaapvaal craton, South Africa, in Archean and early Paleoproterozoic age carbonate-, shale-, and iron formation-bearing marine strata. We sampled contemporaneous strata that record the drowning of the Campbellrand-Malmani carbonate platform and a transition to iron formation deposition in a range of localities, from two metamorphosed (greenschist and above, affected by the intrusion of the Bushveld igneous complex) and four better-preserved (sub-greenschist) deep subsurface drill cores. To evaluate the geochemistry and mineralization tied directly to petrographic textures and cross-cutting relationships, we combined bulk geochemistry with light and electron microscopy and synchrotron microprobe X-ray absorption spectroscopy and imaging to produce Mn speciation maps at the requisite micrometer length scales for these textures. Samples with lesser degrees of post-depositional transformation contained minor amounts of Mn(II) in early diagenetic marine carbonate cements and detrital carbonate grains, while metamorphosed samples typically contained Mn concentrated into a combination of coarse-grained and vein-filling carbonate phases (ankerite, siderite, and rhodochrosite), garnet and amphibole. Chemical imaging analyses of these more metamorphosed samples show that Mn is held by phases and textures that mineralized post-deposition and lithification, demonstrating that Mn was mobilized – at least locally – by metasomatic fluids, although it is difficult to distinguish whether this Mn was original to these strata or was introduced secondarily. Our results confirm that Mn can be mobilized and therefore caution should be applied when interpreting Mn enrichments in sedimentary rocks, especially when Mn enrichment is not geographically extensive and coincides with metamorphic processes.
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46

Wang, Xiao Li, Hui Juan Wang, and Ying Ga Wu. "Time-Space Distribution Characteristics of Nitrogen in Surface Sediment from the Inner Mongolia of the Yellow River." Advanced Materials Research 1092-1093 (March 2015): 996–1000. http://dx.doi.org/10.4028/www.scientific.net/amr.1092-1093.996.

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Time-space distribution characteristics of nitrogen in surface sediment from the Inner Mongolia of the Yellow River were investigated using the sequential extraction method. Sedimentary nitrogen were fractionized into four forms: ion exchange nitrogen (IEF-N), nitrogen combined with carbonate (CF-N), nitrogen combined with iron-manganese oxide (IMOF-N), organic nitrogen and combined with sulfides (OSF-N). The rank order according to the mean concentration of N-fraction in surface sediments from the Inner Mongolia of the Yellow River was OSF-N > IMOF-N > IEF-N > CF-N and the N-fraction content in surface sediments of autumn was higher than that of spring. Moreover, the different degrees of positive correlation between different morphological transformation nitrogen forms and the sum of TN, TP, CEC and organic matter of 12 sediment samples.
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47

Versteegh, Gerard J. M., Andrea Koschinsky, Thomas Kuhn, Inken Preuss, and Sabine Kasten. "Geochemical consequences of oxygen diffusion from the oceanic crust into overlying sediments and its significance for biogeochemical cycles based on sediments of the northeast Pacific." Biogeosciences 18, no. 17 (September 13, 2021): 4965–84. http://dx.doi.org/10.5194/bg-18-4965-2021.

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Abstract. Exchange of dissolved substances at the sediment–water interface provides an important link between the short-term and long-term geochemical cycles in the ocean. A second, as yet poorly understood sediment–water exchange is supported by low-temperature circulation of seawater through the oceanic basement underneath the sediments. From the basement, upwards diffusing oxygen and other dissolved species modify the sediment, whereas reaction products diffuse from the sediment down into the basement where they are transported by the basement fluid and released to the ocean. Here, we investigate the impact of this “second” route with respect to transport, release and consumption of oxygen, nitrate, manganese, nickel and cobalt on the basis of sediment cores retrieved from the Clarion Clipperton Zone (CCZ) in the equatorial Pacific Ocean. We show that in this abyssal ocean region characterised by low organic carbon burial and sedimentation rates vast areas exist where the downward- and upward-directed diffusive fluxes of oxygen meet so that the sediments are oxic throughout. This is especially the case where sediments are thin or in the proximity of faults. Oxygen diffusing upward from the basaltic crust into the sediment contributes to the degradation of sedimentary organic matter. Where the sediments are entirely oxic, nitrate produced in the upper sediment by nitrification is lost both by upward diffusion into the bottom water and by downward diffusion into the fluids circulating within the basement. Where the oxygen profiles do not meet, they are separated by a suboxic sediment interval characterised by Mn2+ in the porewater. Where porewater Mn2+ in the suboxic zones remains low, nitrate consumption is low and the sediment continues to deliver nitrate to the ocean bottom waters and basement fluid. We observe that at elevated porewater manganese concentrations, nitrate consumption exceeds production and nitrate diffuses from the basement fluid into the sediment. Within the suboxic zone, not only manganese but also cobalt and nickel are released into the porewater by reduction of Mn oxides, diffusing towards the oxic–suboxic fronts above and below where they precipitate, effectively removing these metals from the suboxic zone and concentrating them at the two oxic–suboxic redox boundaries. We show that not only do diffusive fluxes in the top part of deep-sea sediments modify the geochemical composition over time but also diffusive fluxes of dissolved constituents from the basement into the bottom layers of the sediment. Hence, the palaeoceanographic interpretation of sedimentary layers should carefully consider such deep secondary modifications in order to prevent the misinterpretation of primary signatures.
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48

Segev, A., L. Halicz, G. Steinitz, and B. Lang. "Post-depositional processes on a buried Cambrian sequence in southern Israel, north Arabian Massif: evidence from new K–Ar dating of Mn-nodules." Geological Magazine 132, no. 4 (July 1995): 375–85. http://dx.doi.org/10.1017/s0016756800021440.

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AbstractThe Cambrian sedimentary sequence in Israel and adjacent countries marks the beginning of the Phanerozoic sedimentation on the Arabian–Nubian craton. The maximal burial of this sequence, in the southernmost part of Israel, was approximaly 2.5 km. Manganese nodules hosted by shales of the marine Cambrian Timna Formation, Timna Valley, were subjected to K–Ar analysis in order to date their Mn-mineral formation. In addition, the <2 μm clay fraction in the host rock was dated by K–Ar and Rb–Sr methods. The K–Ar ages (average 365 ± 4 Ma) and Rb–Sr isochron (381 ± 10 Ma) of the illitic clay fraction yielded a Middle/Late Devonian age. The results imply that K–Ar and Rb–Sr systems of <2μm illites in the Cambrian host rocks, as well as those enclosed in the Mn nodule insoluble residues, were completely resetin a Middle/Late Devonian thermo-tectonic event, coeval with the beginning of a stratigraphically recorded epeirogenic uplift. The Mn-nodules which were studied fall into two types: (1) nodules constituted by massive, well-crystallized hollandite and pyrolusite; and (2) younger nodules of poorly crystallized massive hollandite and coronadite solid-solutions. Type-1 nodules yielded a calculated Early Cretaceous age of 112 ± 11 Ma, whereas type-2 nodules yielded calculated apparent dates of 20 and 49 Ma. The first age suggests a first stage of manganese nodule formation within the Timna Formation, in Early Cretaceous time, possibly genetically connected with the shallow basic intrusions and volcanic explosive activity in the area. The much younger K–Ar dates of type-2 Mn nodules may be due to late manganese remobilization and mineralization processes. This activity is interpreted as being related to the nearby Tertiary Dead Sea rifting, which was accompanied by low temperature hydrothermal processes.
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49

Martínez-García, E., J. F. Antona, A. García Sánchez, and J. L. Quiroga de la Vega. "Tectonic and Metallogenic Significance of Sedimentary Manganese Deposits in the Eastern Cantabrian Domain, Asturias, Northwestern Spain." International Geology Review 46, no. 3 (March 2004): 273–88. http://dx.doi.org/10.2747/0020-6814.46.3.273.

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50

Cheize, M., H. F. Planquette, J. N. Fitzsimmons, E. Pelleter, R. M. Sherrell, C. Lambert, E. Bucciarelli, et al. "Contribution of resuspended sedimentary particles to dissolved iron and manganese in the ocean: An experimental study." Chemical Geology 511 (April 2019): 389–415. http://dx.doi.org/10.1016/j.chemgeo.2018.10.003.

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