not exactly apples with apples

Cliff Head from what I can make of it, is a rather different shape when you compare its surface area and varying degrees of vertical relief with that of the Dunsborough structure.

Roc put out a Schematic Cross-Section for Dunsborough-1 in its 27th June 07 Investor Presentation at slide # 31, if you extrapolate what has been said in todays announcement (and previous info) then I believe it points to a somewhat different shaped structure to Cliff Head and thus a potentially significantly different OOIP potential.

Anyway, only time will tell.

John Doran made the following comments in todays ASX release .......

Subject to completing the coring programme, drilling to Total Depth and running a full suite of
logs, including wireline sampling, this latest well appears to point to a potentially significant
gross hydrocarbon column both at the Dunsborough-2 well and for the field as a whole.

"Subject to all the usual – and very valid – caveats about obtaining further data between now and the end of the well, the Dunsborough-2 results to date appear to be quite encouraging, particularly given that it is about 50 metres down structure and 1.6 kilometres south of the discovery well.

While it is way too early to offer any comment regarding reserves, a comparison of the basic dimensions of the Dunsborough and Cliff Head structures might help provide shareholders and potential investors with a rough perspective should Dunsborough-2 prove to have producible oil.

Cliff Head, about 50 km south of Dunsborough, had original recoverable proved and probable oil reserves of almost 16 MMBO; covers an area of about 6 sq km and has a gross oil column of approximately 60 metres. Dunsborough, as currently understood, covers around 5 sq km and has the capacity for a 90 metre gross oil column."