ÉTOILE FLAMBOYANTE (L’): : JACQUES TRESCASES: Books. La symbolique de la mort, ou, Herméneutique de la résurrection by Jacques Trescases(Book) 8 editions published between and in French and held. Jacques Trescases. Follow. Follow on Amazon. Follow authors to get new release updates, plus improved recommendations and more coming soon.
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It is the dominant climate in the northern part of Brazil, in the Amazonie region.
Trescases, Jacques [WorldCat Identities]
You can view this on the NLA website. Carbonatic protore alteration [link] a The alteration profiles [link] b Chemical and mineralogical evolution [link] 2. Table VI Nickel deposits of Brazil. At the end of the Jurassic period, when these basins were still active, an important tectono-magmatic event South. A great variety of climates can be found in Brazil as a consequence of its continental dimensions. A schematic profile presents, from top to bottom, the following sequence:.
The South American Platform had its evolution during the Pre-Cambrian and was completely consolidated in the beginning of the Paleozoic. It is a sub-horizon of trescasrs thickness 1. The color here is redder, showing a yellow hue ; — w eathered rocks saprolitesometimes intercalated with bauxitic blocks, in the upper part.
Due to morphoclimatic conditions, they are ttrescases scarce in northeastern Brazil and absent in Rio Grande do Sul State. Main Brazilian lateritic ore deposits and their chronostratigraphic relationships modified after Schobbenhaus et al. The primary minerals are quickly altered, undergoing a total loss of silica and bases. Consequently, the paragenesis existing in Urucum represents a result of a partial alteration of a certain protore.
In the Lower Tertiary, during the agradation phase of the South American Surface, the weathering led to the formation of important alteration covers.
It changes upwards into a clay saprolite, without residual rocks, with preserved original structure total thickness around 10 m.
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Michel Cathelineau Michel Cathelineau. Quadrilatero Ferrifero, due to its proximity to the siderurgical center, and Cataguases, due to kacques important reserves recently found.
As a consequence, they are better known when compared with the small deposits of the Northeast and Goias. Considering their importance for trescaees Brazilian mineral economy, two different areas, included in this region, may be mentioned: Haematite is dominant, except locally, when dolomite and amphiboles cummingtonite or tremolite replace quartz.
Nickeliferous laterite profiles from New Caledonia Troly et al. The existence of metavolcanic rocks has been recognized rather recently treescases that Fleischer and Oliveira have suggested an allochthonous origin for these deposits, considering that the itabirite could not be a source of aluminum. Manuscript received December 9, ; accepted July 24, The friable horizon with preserved structure, which is dominant in the ridge deposits, appears scarcely in the plateau profiles ; — a nodular horizon that covers all the plateau alteration profiles.
The plateau profile, like the previous one, shows three main horizons, as follows: The Jcaques Record of the Appalachian Region. The lateritic ore deposits of Brazil 15 being the presence of a kaolinitic clay horizon between the bauxite and the parent rock and a rather important mica content. The pisolites have a manganesiferous core, several Fe-Al-Mn cortex and are embedded in a reddish-brown clay matrix pisolitic material — which may locally attain 10 m.
The iron hydroxides previously formed evolve into goethite and the asbolane remains stable. This rock is formed by the intercalation of jacquse layers of haematite and silex. The manganiferous protore is a carbonatic rock with rhodochrosite, clay minerals, pyrite and carbonaceous fragments with no metamorphism. Sign In or Create an Account.
These plates jacquee harder or even more cemented in the ore originated from the lower units, which is more manganesiferous granular, platy tresczses massive facies, with average content of No lateritic deposits are known up to now in this part of the country.
The magnesium and afterwards the silica are progressively leached, promoting a relative concentration of residual elements — Fe, AI, Cr, Ni, Co, Mn. The Archean basement An important group of rocks associated with Archean units is the large ultramafic complex with gabbros, pyroxenites and peridotites of Goias State Niquelandia, Trescasses Alto and Cana Brava.
Contrary to what was observed in other lateritic deposits, the manganese ores are mainly controlled by lithology, with no association with particular levelling surfaces or recent climatic conditions. Two main mechanisms were important: Please try your request again later. Considering a typical profile, the following horizons can be observed from bottom to top: It can be observed that the sequence of alteration horizons for the Brazilian nickeliferous laterite is similar to those from other places.
The haematite, interlayered with quartz, consists of elongated lamellae, with yum average length, which may reach some millimeters.
In the metamorphosed silico-carbonatic protores the rhodochrosite is associated with manganesiferous silicates: