Massambala Oil Discovery

Roc Oil Company Limited
30 August 2007


30 August, 2007

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

                 EXPLORATION UPDATE: MASSAMBALA OIL DISCOVERY,
                                 ONSHORE ANGOLA

Roc Oil (Cabinda) Company, a wholly owned subsidiary of ROC, is pleased to
advise that the Massambala-1CH2 sidetrack hole has reached a prognosed total
depth of 491 metres and wireline and coring programmes have been completed. The
sidetrack hole was drilled to evaluate a shallow oil zone intersected by
Massambala-1, ROC's first exploration well in Angola.

On 27 August 2007, Massambala-1CH2 was suspended for possible re-entry in order
to determine the commercial merit of the discovery. Laboratory analyses have
been initiated with regard to the fluid and core samples obtained from the
sidetrack well and results are expected during the next several weeks. In the
meantime, a preliminary interpretation of currently available data provides the
following insights:

*   The oil is mobile, not residual.

*   Visually, the oil appears to be heavy and viscous, but definitive
    comment must await laboratory analysis. In any event, the oil seems to bear
    comparison to many crudes that are currently being routinely produced in 
    other parts of the world via standard heavy oil industry production 
    techniques.

*   Although there appears to be a 1 to 2 metre oil sand higher in the section, 
    the sidetrack confirmed that the main zone of interest is a 16 metre gross 
    oil column with approximately 15 metres (94%) of net oil saturated sand with
    good to excellent reservoir qualities and an associated wireline log 
    anomaly.

At the depth of the shallow oil accumulation, approximately 400 metres, the
Massambala feature is currently mapped on 3D seismic data as a gentle four-way
dip structure with a vertical relief in the order of 16 metres at the well which
is located a few metres below the structure's high point. As currently mapped,
the area of structural closure is approximately 26 sq km/6,400 acres and based
on an apparent oil-water contact identified in the well, it would seem that the
shallow Massambala structure is filled to spill.

It is far too early to comment specifically on potential recoverable reserves at
Massambala but volumetric calculations, based on the most recent 3D seismic
mapping and available well data, suggest the in-place oil resource potential
could be in the order of 170 MMBO. In a more generic sense and subject to
specific field details, heavy oil recovery techniques can recover a minimum of
10% of the oil in-place, often about 20% and sometimes considerably more.

Commenting on the Massambala results, ROC's Chief Executive Officer, Dr John
Doran, stated:

'After drilling the original Massambala well last month, there were two main
concerns about the shallow oil accumulation: is it residual and, if not, is the
oil too heavy to be produced via conventional heavy oil industry techniques? The
sidetrack tells us that the oil is not residual and, even if it is heavy, it may
still be producible.

Heavy oil production techniques are an established and increasingly important,
subset of the upstream petroleum business, particularly in countries such as
Canada and Venezuela. Therefore, although ROC's primary exploration target in
Cabinda continues to be the more mobile and lighter crudes typical of the
region, we have had enough exposure to crudes with less amenable flow
properties, through our Cliff Head, Zhao Dong and Beibu Gulf operatorships, to
realise the potential importance of the oil discovery at Massambala.

On this basis, Massambala becomes the most recent addition to ROC's 'conveyor
belt' of projects which merit more thorough appraisal. In Massambala's case, the
thought that it might be possible to produce 20% or more of the in-place oil
using standard heavy oil industry production techniques, provides plenty of
reason for ROC and its co-venturers to take a very close look at the discovery.

Finally, from a purely statistical point of view, Massambala-1 was not only
ROC's first well in Angola and its first well onshore Africa, but also the
Company's fifth exploration success out of nine exploration wells drilled in
three different countries during the last 16 months.'


Participating Interests in the Cabinda South Block are:
    ROC Group Companies (Operator)    60%
    Force Petroleum Limited           20%
    Sonangol P&P S.A.                 20%

In accordance with ASX and AIM Rules, the information in this Release has been
reviewed and approved by Dr John Doran, Chief Executive Officer, Roc Oil Company
Limited, BSc (Hons) Geology, MSc and PhD. Dr Doran, who is a member of the
Society of Petroleum Engineers, has more than 30 years relevant experience
within the industry and consents to the information in the form and context in
which it appears.


Damian Fisher
General Manager
External Affairs & Investor Relations

                                         For further information please contact:
                                                                Dr John Doran on
                                                            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]
                                            Mob: [phone]
                                                     Email:  [e-mail]

                                                                    Michael Shaw
                                    Oriel Securities Limited (Nominated Adviser)
                                                       Tel:  [phone]



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