The Esso/BHP Billiton joint venture in Bass Strait is just one example. The venture is working toward giving $1.1 billion for the second-stage development of the Turrum oil and gas field in early June, The Age reported.

The offshore development on the Gippsland coast has been estimated to be able to tap 1 trillion cubic feet of gas, which is reportedly needed to offset depletion of gas reserves from existing fields.

The first of the oil from the Esso-operated development is expected by 2011. In the initial phase, gas will be re-injected and gas sales are forecast to start in 2015.

The reservoirs will be tapped by drilling two oil wells and four gas wells, and right now regulatory approvals are still being sought while front-end engineering and design work is complete.

There are other developments as well, like Nexus Energy's $195 million development of the Longtom gas field and Santos and its partners' $275 million development of the Henry gas field.