(Adds details on copper production and forecast, background)...

(Adds details on copper production and forecast, background)

Jan 22 (Reuters) - Global miner BHP Group (BHP) BHPB.L said on Tuesday its second-quarter iron ore production fell 9 percent and flagged a $600 million negative impact due to production disruptions at its copper and iron ore operations.

The world's biggest miner said unplanned production outages at Olympic Dam, Spence and Western Australia Iron Ore are likely to negatively impact productivity and flagged that it would revise guidance at its results on Feb 19.

The miner also raised its 2019 copper production forecast to between about 1.6 million tonne and 1.7 million tonne bolstered by the retention of Cerro Colorado copper mine in Chile, after a sale to private equity house EMR Capital fell through.

BHP's iron ore output declined to 66 million tonnes during the three months ended Dec. 31, compared with 72 million tonnes a year ago, hurt by a forced train derailment that caused a supply disruption.

The mining giant had said in November that it expected some interruption to its Australian iron ore exports after it was forced to derail a cargo train loaded with the commodity after it ran away en route to a key shipping hub.

The Anglo-Australian miner has so far maintained its fiscal 2019 guidance of 273-283 million tonne of iron ore from its Western Australian operations.

In other metals, BHP's copper output fell 3 percent at 416,000 tonnes in the quarter, hurt by planned maintenance as well as outages.