PERTH (miningweekly.com) – Diversified giant BHP Billiton’s iron-ore operations in the Pilbara have achieved record production for the nine-month period ended March, despite reporting a 5% production decline between the December and March quarters.

The miner reported on Wednesday that iron-ore production for the three months ended March reached 40.2-million tons, bringing the year-to-date output to some 122.1-million tons.

The decrease in the March quarter production, compared with the December quarter production, was owing to cyclone-related downtime during the period, BHP said. However, it noted that the division was on track to achieve its production guidance of 183-million tons for the 2013 financial year.

Meanwhile, petroleum production increased by 6% year-on-year, with the group producing some 176.57-million barrels of oil equivalent in the year to date.

For the three months ended March, petroleum output amounted to 55.42-million barrels, a 2% decline on the previous corresponding period and a 7% decline on the December quarter.

Production for the petroleum division was again affected by cyclone-related downtime at the Western Australian operations, BHP said, as well as extended maintenance delays and drilling delays at the non-operated facilities in the Gulf of Mexico, and a natural field decline.

The diversified giant has maintained its production guidance for the full year at around 240-million barrels of oil equivalent.

Meanwhile, metallurgical coal production during the quarter increased by 22% compared with the previous corresponding period, and by 1% compared with the December quarter to reach 26.7-million tons during the three months to March.

Metallurgical coal production was also affected by adverse weather conditions during the March quarter; however, BHP noted that recently installed flood-mitigation infrastructure enabled a rapid recovery in performance and noted that the business was operating at full supply chain capacity at the end of the period.

Energy coal production for the period was down 10% on the previous corresponding period and down 15% on the December quarter. BHP reported that it had produced some 53.3-million tons of energy coal during the quarter ended March.

The miner said energy coal production had also been affected by adverse weather conditions on the east coast of Australia and industrial action at Cerejon Coal, in Colombia.

Meanwhile, copper production increased by 9% during the quarter, compared with the previous corresponding period and by 4% on the December quarter figure, to some 876 200 t.

Uranium production also increased by 4% quarter-on-quarter, but declined by 8% compared with the December quarter, with BHP producing 2 989 t.