Landsat Mosaic of the Tapajós

The Tapajós Mineral Province (TMP) is certainly one of the most intriguing and at same time, exciting, auriferous regions in the world. More than 30 million ounces of gold (unofficially) have been produced without the presence of a significant gold mine in the region. For more than 50 years this region of northern Brazil has produced gold just by means of artisanal and very primitive methods. Most of this gold output comes from hydraulic mining of alluvials with some contribution of elluvials and colluvials. In the last decade, mining and grinding of fresh high grade veins has also made a minor contribution. The official government supported production in the TMP is approximately 10 million ounces not including the unreported unofficial production.

During the 1980’s, when gold prices were at their peak tens of thousands of "garimpeiros" (artisanal miners) entered into the heart of the Amazon jungle in search of gold and fortune which could come from the rich Tapajós valley. More than 230 air strips were built to feed and support these "garimpos". At that time the airport of the city of Itaituba was the second busiest in the world with more than 360 daily takeoffs and landings just with small aircraft.

The TMP encompasses the southwest portion of Pará state and the eastern portion of Amazonas state. It has an area of approximately 135,000 km2 which is larger than French Guyana. Itaituba (118,194 inhabitants - IBGE, 2007) is the center which provides almost all support to the "garimpos" and now, also to modern exploration activities.

Nowadays, most of the “easy” alluvial gold has been mined and as a consequence, several primary mineralization sites were exposed close to the surface. First modern exploration took place in the early 1990’s. This first round of exploration was carried out mainly by major companies like Rio Tinto, Barrick, Homestake and TVX. The most successful and persistent company was Rio Tinto which worked from 1992 to 1998. Rio Tinto discovered the São Jorge, Ouro Roxo, Palito and V3 gold deposits. The second round of exploration started in 2004, mainly by junior companies that were attracted by Brazauro’s discovery of the Tocantinzinho gold deposit.

The TMP is the western portion of the Archean-Proterozoic Amazon Craton that covers part of the Pará, Amazonas and Mato Grosso states of northern Brazil. The TMP presents one of the most widespread “granitization” exposures in the world. All main tectono-magmatic events took place in the early Proterozoic from 2.1 Ga to 1.88 Ga. Most gold prolific units are the metamorphosed and deformed granites of the Cuiu-Cuiu Suite and the un-metamorphosed and un-deformed granites of the Parauari Suite. Some gold occurrences also do occur in the acid-intermediate volcanic rocks of the Iriri Group. The widespread alluvial gold deposits point to the area's strong bedrock exploration potential, the placers resulting from the underlying vein-type, stockwork, and disseminated gold mineralization that exists along structurally favorable locations of the major intrusive-fed shear zones running throughout the region.

If the Tapajos was located in Canada, the US or Australia it is likely that tens of companies and multiple drill rigs would be involved in the gold search. Brazauro strongly believes that Tocantinzinho is not the only large gold deposit in the Tapajós. Tocantinzinho may be the first of a series of gold deposits that will be discovered in this rich and exciting region.

Nowadays, the Tapajós region is being regarded by both public and private sectors, as a region which needs infrastructure improvements. The federal government has included the Santarém-Cuiabá road in Brazil's Growing Plan (PAC) to be completely paved in the next three years. This work has already started. A consortium between a state owned energy company and a brazilian private construction company plans to build a 881 MW power plant in the Jamanxim river, 65 km northeast of the Tocantinzinho Project. Two other power plants, 50 MW each, are planned to be built in the next four years, by a brazilian private energy company in the Crepori river at 40 and 50 km from the Tocantinzinho Project. Also, the existent power line, 200 km South of Tocantinzinho Project is being connected to the national energy grid and this would allow an eventual mine at Tocantinzinho to buy energy elsewhere in Brazil.