By Catherine Ngai NEW YORK -LRB- Reuters -RRB- - Global oil prices slidMovement.down.lossfurther on Friday , with Brent on track for the first weekly close below $ 70 a barrel since 2010 , as strongGrow.strongU.S. employment data did little to lift the oil market 's bearishSlow.weakmood a day after Saudi Arabia cutCause.movement.down.lossofficial selling prices .