Oil prices jump, but oversupply worries persist

SEOUL (Reuters) - Oil prices jumped as much as 3 percent on Friday to win back a chunk of the ground they lost in the previous session, but growth in U.S. crude stockpiles and ongoing concerns about the global economy kept markets under pressure.Brent crude was up $1.18, or 2.26 percent, at $53.34 a barrel at 0219 GMT, having earlier risen as much as 3.1 percent. It dropped 4.24 percent, or $2.31, the day before to settle at $52.16 per barrel. U.S. West Texas Intermediate (WTI) crude..