UPDATE 1-U.S. petroleum rail shipments up nearly 50 pct in 2012
By Kristen Hays HOUSTON, Jan 3 (Reuters) - Shipments of petroleum on U.S. railroads rose more than 46 percent in 2012 as shale oil producers put record amounts of crude on trains to overcome pipeline capacity constraints. Petroleum products were the fastest growing cargo category for major U.S. rail
