Self-propelled drilling ship GLOMAR III (2860 tons, built 1963 for Global Marine Inc). Employed by joint-venture partners BHP and Esso Exploration Australia over continental shelf in Bass Strait between Australia and Tasmania in the 1960s. On 18 February 1965 it drilled Australia's first offshore well (Barracouta Well) discovering natural gas in the Gippsland Basin, Bass Strait. They expected oil, but the best was yet to come. Oil was discovered in 1966. (That's not an oil slick in the upper part of the photo, it discoloured over time.)