Lateritic weathering of trachyte, and bauxite formation in …
Bauxites and Fe laterites were formed on Neogene volcanics from Fongo-Tongo region in the highlands of western Cameroon, and are distributed on plateaus, slopes and downslope surfaces. Bauxitic profiles result from intense in-situ weathering of trachytes that implied depletion of silica and labile elements from the saprolite, while alumina …
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Mineralogy and geochemistry of the Zhuxi Nb-rich
The Zhuxi trachytic rocks are predominantly composed of trachyte ignimbrites and trachytes, with pronounced Nb contents of 213–627 ppm and 116–384 ppm, respectively. ... However, others emphasized that metasomatism played a significant role in remobilizing and transporting Nb from primary magmatic minerals to alkali-rich fluids …
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(PDF) Distribution of duricrusted bauxites and laterites on …
Our results document two major bauxitic phases in the Fongo-Tongo area, i.e., mid-Miocene primary in situ bauxitic weathering of trachyte and late Miocene secondary bauxitization of previously ...
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Trachyte
The crystals found in Trachyte are primarily composed of alkali feldspar, which is rich in potassium and sodium. Additionally, Trachyte may contain either nepheline or small …
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Rare metal enrichment of the Tianbao trachytic complex
The primary ore minerals are evenly dispersed throughout the rock and include lueshite/natroniobite and complex Na–Fe–Zr–Nb–Y–REE silicate minerals dominated by a eudialyte group mineral ...
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Phanerozoic extensional faulting and alteration control …
The primary uranium minerals are preserved in the unweathered trachyte, consistent with Abdel Gawad and Attawiya (1966) who identified pitchblende in El Atshan trachyte. The low U contents of zircon in the investigated uraniferous trachyte samples probably also reflect the release of U from their hosting minerals (such as zircon) due to …
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Trachyte | SpringerLink
Arsoite —a leucotrachyte related to rhomb porphyry and kenyte; Arso-type trachyte. Calcitetrachyte —contains>10% calcite, probably primary. Drachenfels trachyte ( …
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Trachyte : Composition, Formation, Classification and …
Trachyte is a relatively homogenous rock type in terms of its composition, consisting primarily of alkali feldspar minerals, with smaller amounts of other minerals like quartz, biotite, and hornblende. While it doesn't exhibit the same wide variety of types and varieties as, for example, … See more
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Partial melt generation and evolution of magma
Trachyte magma pressures 0.3–2.5 kbar, ... Geochemistry and the petrological approach can overcome this challenge by utilizing minerals and their carrier melt to provide information about storage temperature and pressure conditions, ... The primary magma in Paka was most probably generated by 5–10% partial melting of …
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Petrophysical and mechanical properties of Euganean trachyte …
Euganean trachyte is a subvolcanic porphyritic rock extracted in northern Italy with an age-old tradition of use as dimension stone, historically linked, in particular, to the fervent building activity brought by the Roman Empire and, later on, the Republic of Venice Serenissima.The results of a comprehensive petrophysical and mechanical …
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Trachyte
Trachyte is a fine grained and generally light coloured volcanic rock that usually has a rough surface to the touch which is the reason it was given that name trachys. 'The major mineral component of trachyte is alkali feldspar and it generally contains no quartz. Trachyte lava is of moderate viscosity and forms thick lava flows and domes ...
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Trachyte | SpringerLink
'Trachyte' published in 'Petrology' Arsoite —a leucotrachyte related to rhomb porphyry and kenyte; Arso-type trachyte.. Calcitetrachyte—contains>10% calcite, probably primary.. Drachenfels trachyte ( drakonite)—phenocrysts of sanidine and plagioclase in a groundmass of alkali feldspar microlites with accessory minerals (Drachenfels, W …
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Understanding Trachyte, a Fine-grained Volcanic Rock
Trachyte rock has mostly alkali feldspar and lesser sodic plagioclase minerals. Also, it may have no or minor quartz and minor mafic minerals, especially …
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Geology
The major mineral component of trachyte is alkali feldspar (e.g. orthoclase), and it generally contains no quartz. Trachyte often displays trachytic texture, where acicular to tabular feldspar phenocrysts align in …
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primary minerals of trachyte
Trachyte Trachyte,, light-coloured, very fine-grained extrusive igneous rock that is composed chiefly of alkali feldspar with minor amounts of dark-coloured minerals such as biotite, amphibole, or pyroxene Compositionally, trachyte is the volcanic equivalent of the plutonic intrusive rock syenite Most primary minerals of trachyte Know More
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What Is Porphyry? How Does It Form, and In Which Rocks?
Its mineral composition is between granite (felsic) and gabbro (mafic). Also, it has mainly sodium-rich plagioclase and lesser amounts of quartz, amphibole, hornblende, or pyroxene. ... Trachyte porphyry. A trachyte porphyry textured rock features sanidine phenocrysts in a fine-grained groundmass. The groundmass has mainly alkali felspar …
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Understanding Trachyte, a Fine-grained Volcanic Rock
Let us now look at the chemical and mineral composition of trachyte. 1. Chemical composition. Trachyte is an intermediate to felsic or acidic rock. It is high in alkali oxides with Na 2 O + K 2 O > 7 and low in iron and magnesium. Data from Le Maitre (1976) from 534 samples has an average weight % of chemical composition to be SiO 2: …
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Mineral and geochemical characterization of a leptic
Mineral transformations. Trachyte weathering in both soils is associated with the appearance of halloysite and goethite. The process of their formation can be related to deep and intense hydrolysis of primary minerals during which released Al combines with the remaining Si to form halloysite (Certini et al., 2006) whereas Fe crystallizes into ...
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Trachyte | Natural Atlas
On Wikipedia. Trachyte is an extrusive igneous rock composed mostly of alkali feldspar. It is usually light-colored and fine-grained, with minor amounts of mafic minerals, and is …
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(PDF) GEOLOGY AND RADIOELEMENTS POTENTIALITY OF
Trachyte rocks of Wadi Al-Owayrishah and its surroundings crop out in the form of sheets and dykes. They are striking and dipping in a concordant manner with the primary and secondary ...
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Trachyte Igneous Rock
Price: $4.29. Trachyte is a white to light gray extrusive igneous rock. Major minerals include feldspar and biotite mica. Trachyte has a porphyritic texture which is mostly fine-grained with many large grains visible. An information card with details on the rock formation, mineral content, characteristics, and uses is included.
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ALEX STREKEISEN-Trachyte-
Trachyte. Trachyte is a fine-grained and generally light-colored volcanic rock that usually has a rough surface to the touch which is the reason it was given that name (trachys is "rough" in the Greek). Trachytes are composed chiefly of alkali feldspar with minor amounts of dark-coloured minerals such as biotite, amphibole, or pyroxene.
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Geology
Trachyte Trachyte is an extrusive rock, belonging to the alkali series of intermediate volcanic rocks. The major mineral component of trachyte is alkali feldspar (e.g. orthoclase), and it generally contains no quartz.Trachyte often displays trachytic texture, where acicular to tabular feldspar phenocrysts align in one direction, suggestive of flow …
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Trachyte
Trachyte is a volcanic equivalent of syenite. Syenite is a feldspar-rich plutonic rock which is similar to granite but lacks or contains very little quartz. Mafic minerals in trachyte are usually biotite, amphiboles …
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Rhyolite Rock | Properties, Composition, Formation, Uses
Rhyolite. Rhyolite is felsic igneous extrusive rock and it is a fine-grained and dominated by quartz (>20%) and alkali feldspar (>35%).Due to the high silica content, rhyolite lava is very viscous. It is often difficult to identify rhyolites without chemical analysis due to their glassy groundmasses. Many rhyolites consist mainly of glass, and are …
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Mineral control of organic carbon storage in acid temperate forest
Quartz was the dominant primary mineral in the sandstone-derived soil (almost 75% of the mineral fraction) and the mean was 50–60% higher than in the soils derived from basalt and trachyte (Table 2 and Supplementary Data 1). By contrast, highly weatherable minerals such as plagioclases were detected in the volcanic soils.
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(PDF) Teplá trachyte weathering phenomena …
Its primary minerals consists of plagioclase feldspar, quartz, alkali feldspar, biotite, and hornblende, the most common accessory minerals include apatite, zircon, sphene, ilmenite, and magnetite.
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Trachyte
Trachyte: "A quartz-poor volcanic rock in which 65-95% of the feldspar is alkali feldspar." Photos. Hand Sample Photos (3) Thin Section Photos (2) Typical Minerals. sanidine. augite. glass. Information about and links to …
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Trachyte
Mafic minerals in trachyte are usually biotite, amphiboles (hornblende or arfvedsonite), and pyroxenes ( diopside, augite, aegirine). Aegirine and arfvedsonite occur in the rock …
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Monazites reveal timing and genesis of Nb-REE
The primary ore minerals are evenly dispersed throughout the rock and include lueshite/natroniobite and complex Na–Fe–Zr–Nb–Y–REE silicate minerals dominated by a eudialyte group mineral ...
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