by Pedro Jacobi

This region is bounded by the Amazon Basin to the North, in the proximity of Itaituba and the Cachimbo Graben to the South.gold, copper, molly, mineral exploration, brazil, amazon, geology, consultant, properties, minerals, tantalite, porphyries, consultants, quartz, amethyst, diamonds, tapajos, garimpo, garimpeiro

In spite of some preserved Archaen supracrustals (Jacareacanga) Tapajos geology is characterized by a huge volume of anorogenic granites and co-magmatic volcanics (Uatumã Supergroup) of Proterozoic age. Proterozoic sediments are confined to grabens. Mafic Proterozoic intrusions, sometimes layered, are frequent. Younger, Paleozoic/Mesozoic sediments are restricted to the large intracratonic Amazon Basin and to the Cachimbo Graben.

Main Proterozoic units are:gold, copper, molly, mineral exploration, brazil, amazon, geology, consultant, properties, minerals, tantalite, porphyries, consultants, quartz, amethyst, diamonds, tapajos, garimpo, garimpeiro

Parauari granitoids (1.9-2.2Ga), frequently showing rapakivi textures, are calc-alkaline with flat HREE, weakly enriched in LREE and related to the Trans-Amazonian Orogeny. Parauari intrusions, form large batoliths and have RB/Sr ratios, in average, above 1.gold, copper, molly, mineral exploration, brazil, amazon, geology, consultant, properties, minerals, tantalite, porphyries, consultants, quartz, amethyst, diamonds, tapajos, garimpo, garimpeiro

Acid to intermediate volcanics (Iriri) with subordinated pyroclasts and sediments (1.7-1.9Ga). Volcanics are rhyolites, dacites, andesites, trachytes, tuffs, aglomerates and breccias. gold, copper, molly, mineral exploration, brazil, amazon, geology, consultant, properties, minerals, tantalite, porphyries, consultants, quartz, amethyst, diamonds, tapajos, garimpo, garimpeiro

Late stage granitoids, with alkaline chemistry, generally described as Maloquinha, intrude both Parauari and volcanics. Maloquinha rocks are dated 1.84 Ga. These younger granitoids are more fractionated than Parauari rocks having a Rb/Sr > 1, high Nb/Zr and Gd/Yb ratios. Such intrusives had a very shallow depth emplacement. They are frequently red and may have a porphyry-like texture. These granitoids also carry anomalous F, Zr, REE, Y, Sn, Au and Cu, playing an important role in Tapajós mineral economics.gold, copper, molly, mineral exploration, brazil, amazon, geology, consultant, properties, minerals, tantalite, porphyries, consultants, quartz, amethyst, diamonds, tapajos, garimpo, garimpeiro

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ouro, cobre, molibdenita, pórfiros, exploração mineral, amazônia, brasil, geologia, consultor, áreas, garimpos, minerais, quartzo, tantalita, ametista, citrino, diamantes, tapajós,

gold, copper, molly, mineral exploration, brazil, amazon, geology, consultant, properties, minerals, tantalite, porphyries, consultants, quartz, amethyst, diamonds, tapajos, garimpo, garimpeiro