Alcoa Inc has declared force majeure at its Australian alumina operations in the latest fallout out from a gas explosion that has cut supplies to the country's key mining area.

Alcoa said in New York late on Tuesday its second-quarter profit would be 2 cents to 3 cents a share lower as a result of the force majeure on its supply contracts for alumina, the raw material it uses in its smelters to produce aluminum.

Alcoa of Australia is 60 percent owned by U.S. based Alcoa and 40 percent owned by Alumina Ltd . Alumina said the disruption would cost it between A$12 million ($11.3 million) and A$17 million in after tax earnings in the year to June 30.

An explosion on June 3 at Apache Energy's Varanus Island facility in Western Australia state shut Apache's gas production operations, disrupting power supplies to Western Australia state.

The state supplies about a third of the world's iron ore, 20 percent of the gold and tens of thousands of tonnes of copper, nickel, zinc, lead and other industrial staples. It is home to 1,030 operating mine, producing over 50 different minerals. Apache has said it would be two months or more before gas supply was restored [ID:nSYD25010], prompting a rush among miners to find alternative sources.

Australia's national government has offered help to Western Australia state, media reports said on Wednesday.

The state's other main gas supplier, Woodside Petroleum Ltd , has warned it was only capable of making up a fraction of the lost Apache output, which accounts for about a third of the state's overall requirements.

BHP Billiton Ltd/Plc said the shortage was hitting operations but predicted little impact on earnings.

We view the gas situation in WA (Western Australia) with some concern, Chief Executive Marius Kloppers said in an interview broadcast on Sky Business television on Wednesday. There's no doubt there's been an impact.

BHP produces nearly 3 million tonnes of alumina from its Worsley refinery in Western Australia, as well as 165,000 tonnes of nickel, 100 million tonnes of iron ore and other minerals from other sites using gas from Apache.

About a quarter of BHP's profits come from Western Australia. BHP's iron ore and nickel mines were running normally, a company spokeswoman said.

After finding other sources of gas, Minara Resources Ltd , Australia's second largest nickel miner, cut its forecast output this year to between 31,000 tonnes and 35,000 tonnes from 34,000 to 38,000 previously [ID:nSYD117278].

Oxiana Resources Ltd was forced to buy electricity to restore production to normal levels at its zinc mine. Iluka Resources Ltd has stopped mining minerals sands from deposits hit by the gas crunch.

Rio Tinto Ltd/Plc , the state's biggest iron ore miner, said its iron ore operations had yet to be affected, though it was keeping the situation under close review.

Newcrest Mining Ltd said it would lose about 30,000 ounces of gold production, along with copper contained in the gold ore. (Reporting by James Regan in SYDNEY and Steve James in NEW YORK; editing by Jonathan Standing)

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