The tussle for supremacy between OPEC and U.S. shale drillers is killing off older oil fields at the fastest pace in almost a quarter century. That could hurt the industry once the current glut has faded. The three-year price slump triggered by the battle for market share choked off funds for aging deposits elsewhere, accelerating their decline. Output at older fields from China to North America -- making up a third of world supply -- fell 5.7 percent last year, the most since 1992, according to Rystad Energy AS. It’ll drop about 6 percent in 2017 if oil stays at current prices, the consultant said. Oil fell from ... (full story)