(ShareCast News) - BHP Billiton said on Monday that it plans to spend around $900, or 18% of its overall capital budget on exploration next financial year.Speaking at Citigroup's Mining Exploration Day in Sydney, the company's head of geoscience, Laura Tyler, said BHP's petroleum exploration programme is focused on three conventional deepwater basins in the Gulf Of Mexico, the Caribbean, and the Northern Beagle sub-basin off the cost of Western Australia.The company's copper exploration will focus on copper porphyry and skarn deposits in deposits in Chile, Peru and the south west of the US. It will also target sedimentary hosted copper deposits in the north of Canada and iron oxide copper gold deposits in South Australia's Stuart Shelf."We are investing at a time when most in our sector continue to reduce discretionary spend," she said."We are also challenging existing paradigms with a scientific based and disciplined approach to exploration. We have reduced exploration operating costs by 70% since 2013, and this year we have increased the targets tested by 44%."Last week, the miner said it expects costs to drop 16% over the next year and for coal production to grow 8% between now and 2018.