<正> Updated petroleum prospecting technology used in the DaqingOil Field in recent years has allayed fears stemming from gloomypredictions in the 1990s that its reserves would dwindle and its futurewas uncertain.In the past 3 years,184.52 million tons of petroleumand 8.381 billion cubic meters of natural gas have been prospectedin Daqing.According to the president of PetroChina CompanyLimited,with rational exploration Daqing Oil Field reserves will lastanother 100 years.