Tapping what may be the biggest oil finds in the Western Hemisphere in three decades will require equipment that can withstand 18,000 pounds per square inch of pressure, enough to crush a pickup truck, pipes that can carry oil at temperatures above 500 degrees Fahrenheit (260 Celsius) and drill bits that can penetrate layers of salt more than one mile thick.

Petrobras is betting on the Tupi and Carioca fields to become one of the world's seven biggest crude exporters but until the tools needed to exploit the reservoirs are invented, the crude will remain locked under the sea, according to Matt Cline, a US Energy Department economist.

"This is a very, very technically challenging environment where no one's ever done this", said Cline, who tracks the Latin American oil industry. "These discoveries are in very deep water, and once you get to the seabed they are very deep under the floor, with a layer of salt that is definitely a difficult barrier."

Brazil's oil will be harder to develop than the Gulf of Mexico, where the deepest wells are now in production, Cline said. Exxon Mobil Corp. and Chevron Corporation, the two biggest U.S. oil companies, saw diamond-crusted drill bits disintegrate and steel pipes crumple when they attempted to tap deposits beneath the Gulf's seafloor two years ago.

Pumping oil from the Brazilian finds, parts of which are 10,000 meters below the ocean's surface, will require boring almost twice as far down as the world's deepest producing offshore well.

Engineers will have to overcome temperatures that range from near freezing above the ocean floor to temperatures that can melt bismuth, used for transporting uranium rods and for shotgun shells. Layers of salt will also increase the challenge because the crystals absorb seismic waves used to pinpoint oil deposits.

"The seismic issue is important because if you don't identify the location of the oil properly, you're going to waste a lot of money when you drill the hole in the wrong spot" said Vital, a former Exxon engineer.

Brazil pumped 2.13 million barrels of oil a day in the last three months of 2007, more than OPEC members Angola, Libya and Algeria.

Tupi, 250 kilometers off Brazil's coast, may begin production by 2012, according to consulting firm Strategic Forecasting in Austin, Texas. The field may have 8 billion barrels of recoverable oil.

No start date has been set for Carioca, which Petrobras said will take at least three months to evaluate. A Brazilian regulator said this month the reservoir may have 33 billion barrels. If confirmed by further drilling the reserves will be triple the size of Alaska's Prudhoe Bay, the largest US field.

The ocean-depth record for production was set last year by Anadarko Petroleum Corp extracting natural gas from beneath 8,960 feet of water in the Gulf of Mexico, where pressure measures 3,069 pounds per square inch, squeezing joints and tearing at seals.

"What we do at that water depth in the ocean is similar to NASA's space program, but they get to do it without any pressure trying to attack them", Kevin Renfro, production engineering manager at Woodlands, Texas-based Anadarko, said in a November interview.

Petrobras hasn't said how much it spent to sink wells at Tupi and Carioca. Similar drilling by Exxon and Chevron Corp. in the Gulf of Mexico cost 180 million to 200 million US dollars for each well.

Chevron, which has the deepest Gulf of Mexico exploration well, including distance below the seafloor, destroyed as many as a dozen 50,000 US dollars drill bits at each of the 14 wells in its 4.7 billion US dollar Tahiti project.

Exxon Mobil abandoned a Gulf project that would have been the deepest well after pressure and heat shut down the venture in August 2006. The Irving, Texas-based company developed pipes tough enough to withstand temperatures that would shatter regular steel at its Sakhalin-1 project in Russia. The metal may help make Brazil's offshore fields accessible, Vital said.

"These challenges in the Brazilian offshore area are too great for any one company or even country to be able to digest themselves," insists Vital.

Mercopress

"It is the largest discovery in the oil market in the last 30 years, and this field, named Carioca, might be the third largest in the world," said Haroldo Lima.

According to Lima, the Carioca field is located near the Tupi field discovered last year. He stated that the new field contains reserves estimated at 33 billion barrels of oil equivalent (petroleum and petroleum gases), whereas the Tupi field contains reserves estimated to be between 5 million and 8 billion barrels.

The Tupi discovery was announced last November 8. At the time the state company informed that it had concluded the analysis of formation tests conducted in the second well of the area baptized as Tupi, in the bloc BM-S-11, located in the Santos Basin, in the pre-salt layer.

The volume of light oil (28º API) was estimated between 5 billion and 8 billion barrels of oil and natural gas.

On January 21st, Petrobras disclosed the existence of large reserves of natural and condensed gas (very light oil) in the pre-salt layer (deep layer of rock) in Santos Basin. According to the organization, the main well, in bloc BM-S-24, was located 290 kilometers away from the coast of Rio de Janeiro.

"This field will help us reach independence in the sector," stated the minister of Mines and Energy, Edison Lobão, in Brasí­lia, at the time of the announcement. "In terms of gas, there are gigantic proportions."

The statement also added that the consortium that explores Jupiter, made up of Petrobras and Galp Energia, from Portugal, is going to continue investigating the dimensions of the new natural and condensed gas reserves.

The Exploration and Production director of Petrobras, Guilherme Estrella, said that the reserves may guarantee self-sufficiency in gas. Still according to Estrella, there was great expectations for new discoveries at Santos Basin, as most of the 15 fields drilled presented successful results in the tests executed.