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BUENOS AIRES, July 24 (Reuters) - Argentina's giant VacaMuerta shale oil and gas field has 661 billion barrels of oiland 1,181 trillion cubic feet of natural gas resources,according to estimates by state-run energy firm YPF ina presentation seen by Reuters.
Argentina last week relaxed regulations in its petroleumsector, enabling a $1.24 billion agreement between the recentlynationalized YPF and U.S.-based Chevron Corp to developpart of Vaca Muerta.
Few estimates for Vaca Muerta's resources exist and YPF's isa preliminary take, but the 7.4-million-acre formation isthought to be one of the world's most promising shale areas.
YPF operates in 3 million net acres in the formation, anarea with 316 billion barrels of shale oil and 353 trillioncubic feet of shale natural gas resources, according to thepresentation.
U.S.-based Apache, ExxonMobil and AmericasPetrogas also have rights to explore in some 6.8 million acresalong with YPF.
Other companies with a slice of the formation includeFrance's Total, Canada's Madalena Ventures andAzabache, Royal Dutch Shell, the localaffiliate of Brazil's Petrobras, Argentina's Tecpetrol,and Pan American Energy, controlled by Britain's BP.
A U.S. Department of Energy report has shown Argentina holds802 trillion cubic feet of commercially viable natural gasresources trapped in shale rock and 27 billion barrels of oil,the bulk of it located in Vaca Muerta. That would make Argentinathe second largest holder of shale gas reserves after China andNo. 4 in shale oil.
Argentina is counting on Vaca Muerta to recover the energyself sufficiency it lost a decade ago. The government has had tospend millions of scarce dollars importing energy, eroding itstrade surplus.
