Exxon Mobil Corp (XOM.N) has begun marketing U.S. shale gas properties as it ramps up a long-stalled program that aims to raise billions of dollars to shed unwanted assets and reduce debt taken on last year. The top U.S. oil producer three years ago set a goal of raising $15 billion from sales by December. More recently, it promised to accelerate lagging sales to whittle a record $70 billion debt pile. The company’s XTO Energy shale unit is seeking buyers for almost 5,000 natural gas wells in the Fayetteville Shale in Arkansas, spokeswoman Julie King confirmed. Exxon is marketing the properties itself and aims to receive bids this month, people familiar with the matter said. “We are providing information to third parties that may have an interest in the assets,” King said. No buyers have been identified, she said, declining to confirm the August […]