Drilling Update: Cliff Head-5

Roc Oil Company Limited
25 February 2005




25 February 2005

                        ROC OIL COMPANY LIMITED ('ROC')
                              STOCK EXCHANGE RELEASE

                    DRILLING ACTIVITY UPDATE: CLIFF HEAD - 5

KEY POINT

•   Cliff Head-5 (CH-5), a vertical, 'pathfinder', appraisal well in the
    Cliff Head Oil Field, offshore Western Australia, is being plugged and
    abandoned after encountering the top of the reservoir target 56 metres low
    to prognosis and coincident with the field's oil-water contact. The Ensco 56
    rig will now move to drill the next well in the programme, Cliff Head-6
    (CH-6), approximately 2.3 km northwest of the CH-5 location.


Roc Oil (WA) Pty Ltd, as Operator of the WA-286-P Joint Venture (the 'Joint
Venture'), advises that the CH-5 appraisal well has reached a Total Depth of
1,516 metres and completed wireline logging. As of 0600 hours on Friday 25
February (Australian Western Standard Time) the current operation was preparing
to plug and abandon the well prior to the rig moving approximately 2.3 km to the
northwest to drill CH-6, the second well in the planned two well programme.

CH-5 is a vertical 'pathfinder' appraisal well located about 1 km southeast of
the CH-1 discovery well. The primary purpose of CH-5 was to determine the nature
and extent of the reservoir in the East Ridge portion of the Cliff Head
structure which had not previously been drilled. The well encountered the top of
the main reservoir target sand 56 metres low to prediction and coincident with
the field's oil-water contact. The discrepancy between the prognosed and actual
depth at top reservoir target level is currently interpreted to be mainly due to
unexpected seismic velocity variations in the overlying sequence in that part of
the field. The reservoir quality of the target sand sequence drilled by CH-5 is
the best yet encountered in the Cliff Head area.

The results of CH-5 indicate that the depth configuration of the field at top
reservoir level needs to be refined in the light of additional subsurface data
points and with particular reference to the seismic velocity variations. This
work is currently underway. Until the work has been completed, during March
2005, it is not possible to make any definitive statement about the impact which
the CH-5 well has had on field reserves. Directionally, however, it would seem
that proved and probable recoverable oil reserves at Cliff Head may be reduced
by a few to several millions of barrels of oil ('MMBO') from the previously
quoted range of 18 to 21 MMBO. It is possible that the addition of the new
velocity variation information to the field database will cause other parts of
the structure, which are currently mapped as being below the oil-water contact,
to be remapped as being above that contact. Whether or not this will prove to be
the case will not been known until after the drilling of CH-6 which should be
complete in early March 2005. A Final Investment Decision will also wait upon
the results of CH-6.

Commenting on the results from CH-5, Dr John Doran, ROC's Chief Executive
Officer, stated that:

'Fifty-six metres is a big seismic bust, particularly at relatively shallow
depth. Seismic velocity variations of this magnitude can work against you - as
they have plainly done at the CH-5 location - or, they can work for you, as
could happen in other parts of the structure. However, whether or not that will
happen elsewhere within the Cliff Head field is pure speculation at this stage.
The fact that the target reservoir sands in CH-5 represent the best quality
sands seen in the field area offers a degree of ironic comfort.'


The WA-286-P Joint Venture comprises:                 Equity

    Roc Oil (WA) Pty Ltd (Operator)...................37.5%
    AWE Oil (Western Australia) Pty Ltd...............27.5%
    Wandoo Petroleum Pty Ltd..........................24.0%
    Voyager (PB) Limited...............................6.0%
    CIECO Exploration and Production
    (Australia) Pty Ltd................................5.0%


Bruce Clement
Chief Operating Officer                  For further information please contact:
                                                                   Dr John Doran
                                                            Tel: [phone]
                                                            Fax: [phone]
                                                     Email: [e-mail]
                                                         Or visit ROC's website:
                                                               www.rocoil.com.au

                                                                   Dr Kevin Hird
                                            General Manager Business Development
                                                       Tel:  [phone]
                                                       Fax:  [phone]
                                                      Email:  [e-mail]

                                                                    Nick Lambert
                                            Bell Pottinger Corporate & Financial
                                                        Tel:  [phone]



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