Researchers decided to name the underground river the Hamza, in tribute to the scientist of Indian origin Valiya Mannathal Hamza, who has been studying the region for more than four decades.
The discovery was made possible thanks to research work performed at 241 wells that the Petrobras oil company drilled in the Amazon region in the 1970s while prospecting for crude, according to the study published by the Sao Paulo daily O Estado which was carried out by the National Geophysical Observatory.
The subterranean river runs at a depth of about 4,000 meters along a course similar to that of the Amazon, and it has a flow rate calculated at about 3,000 cubic meters per second.
The flow is just 3 percent of that of the Amazon River itself, which has its headwaters in the Peruvian jungle, empties into the Atlantic in northern Brazil and at 6,800 kilometers is considered to be the world's longest river.