The first commercial offshore production in the Perth basin off Western Australia will begin shortly when one of the country’s smaller oil fields is activated.
If it were to hold at an initial 10,000 b/d for all of its first year on line, Cliff Head field will have recovered more than one fourth of the 14 million bbl of proved and probable reserves.
Cliff Head, when discovered at Roc Oil Co. Ltd.’s first well in Australia in late 2001, was not commercial at then-prevailing oil prices near $20/bbl, said John Doran, Roc Oil chief executive officer.
The field figures in an OGJ special report on Australia that starts on p. 20.
Cliff Head is in 59 ft of water 7 miles off Geraldton in the Indian Ocean. It will become Australia’s fourth offshore oil producing region after the Bass Strait, Northwest Shelf, and Timor Sea.
Cliff Head field, on the WA-31-L production license, has oil in a stacked series of Permian sands at about 4,100 ft subsea in a structure sealed by Early Triassic Kockatea shale. The joint venture didn’t make the final investment decision until March 2005.
Oil at one of the delineation wells was reported to be of 33° gravity.
After setting the unmanned platform jacket at the field location in late December 2005, the Ensco 67 jack up began drilling the five producing wells to have electric submersible pumps and two water injection wells.
Upon completion of drilling in the field in April 2006, the rig is to begin a multiwell exploration program on nearby prospects.
Cliff Head oil will be pumped through an 83⁄4-mile pipeline to onshore processing facilities at Arrowsmith, and the crude will be trucked 215 miles to BP Australia Ltd.’s Kwinana refinery south of Perth.
Interests in the Cliff Head venture, with a capital investment of $265 million (Aus.), are Roc Oil, Sydney, 37.5%; Australian Worldwide Exploration Ltd., Sydney, 27.5%; Wandoo Petroleum Pty. Ltd. of Japan, 24%; Voyager Energy Ltd., Perth, 6%; and CIECO Exploration & Production (Australia) Pty. Ltd., 5%.✦
