2D Seismic Interpretation

Rockhopper Exploration plc
05 February 2007


                                                             


PRESS RELEASE


5 February 2007


2D Interpretation Update


• Ernest contains multiple zones of interest - target size increased by 30%

• Newly mapped Lead K closure co-incident with CSEM response

• 20 additional structural leads identified


Interpretation of the 920km 2D seismic data collected in early 2006 is complete
and Rockhopper Exploration is pleased to provide the following exploration
update.

The 2D seismic data, when combined with the controlled-source electromagnetic
survey (CSEM) data gathered in late 2005, gives the Company increased confidence
in prospect Ernest such that the potential recoverable P50 reserve estimate has
been increased by 30% to 130 mmbbls. In addition, on Lead K, a closure has been
confirmed coincident with that identified by CSEM and could contain 60 mmbbls
recoverable.

A further twenty structural leads have been identified which warrant further
investigation. It is estimated that nine of these could be sufficiently large to
each contain over 100 mmbbls recoverable and of those seven could each contain
over 200 mmbbls recoverable.

The data was collected over two areas, firstly over Ernest, secondly over the
southernmost areas of licences PL023 and PL024. The data over Ernest has been
interpreted in conjunction with the CSEM data collected at the same time.

Ernest

As a result, Ernest can now be mapped at multiple levels, with at least two
zones of interest on the new seismic data from c.980m depth to c.2000m depth.
The new 2D has also allowed us to further refine our estimates of the potential
size of the prospect.

The CSEM data over Ernest shows a single discreet resistor on Line 1 (East /
West) at a level of approximately 1500m. This is coincident with the deeper
closure mapped on the seismic.

Additionally, the CSEM data over Ernest shows two discreet resistors on Line 2
(North / South); one appears to be at the deeper level and is coincident with
the resistor described above. The second appears to be at a shallower level and
appears to be coincident with a separate closure, still part of Ernest, at a
level of approximately 1100m. We have also observed an amplitude versus offset
(AVO) anomaly on the flank of Ernest at this shallower level which is coincident
with the CSEM response.

When the CSEM is combined with the new 2D, Ernest now appears to have multiple
zones of interest with at least two possible targets confirmed by both the CSEM
and seismic data.

We now believe that Ernest could possibly contain more than the 100 mmbbls of
recoverable oil and have therefore revised our estimates upward to a P50 of 130
mmbbls and a P10 of over 250 mmbbls recoverable.

Lead K

In the southern area we collected a wider grid of data over a number of leads
including Lead K over which CSEM was also collected. Lead K exhibits a positive
CSEM response, but this was not coincident with the original target. However, a
separate closure, coincident with the CSEM response, is now evident on the new
seismic. The area of Lead K which is coincident with the CSEM response could
contain 60 mmbbls of recoverable oil. Lead K was not specifically included in
the EMV calculation carried out by Scott Pickford at the time of the Company's
admission to AIM.

Twenty additional structural leads

We have also identified 20 additional structural leads which merit further
investigation. These range in size up to over 13,000 acres and the shallow water
depth and proximity to the Falkland Islands would lead to strong economics, were
a discovery to be made. A number of those leads are associated with bright
amplitudes, providing further encouragement. Some of the leads are large in size
and all are defined by structural closure.

Finally, a large area of bright amplitudes has been observed in the very shallow
water area near the Falklands in licence PL024. This could possibly indicate a
significant stratigraphic lead which also merits further investigation.

Rockhopper Exploration's Managing Director, Sam Moody, said:

'The information provided by the interpreted seismic is highly encouraging. The
two areas covered by CSEM have been further defined with the new seismic data
and we have a significant number of leads to examine in licences PL023 and
PL024.

As previously announced, we have just completed the acquisition of 3D seismic in
our northern licences PL032 and PL033 and are on course to developing a number
of drillable prospects by the third quarter of 2007.

During the last 12 months we have successfully acquired 2D, 3D and CSEM data and
have significantly progressed our exploration portfolio as a result.'

NB: This statement has been approved by the Company's geological staff who
include David Bodecott (Exploration Director), who is a Member of Petroleum
Exploration Society of Great Britain (PESGB) and the American Association of
Petroleum Geologists (AAPG) with over 30 years of experience in petroleum
exploration and management, for the purpose of the Guidance Note for Mining, Oil
and Gas Companies issued by the London Stock Exchange in respect of AIM
companies, which outline standards of disclosure for mineral projects.

This interpretation has been undertaken by the Company's technical staff and
reflects their best professional judgement. The accuracy and completeness of the
information contained herein has not been independently verified.


For further information, please contact:

Rockhopper Exploration plc www.rockhopperexploration.co.uk
Sam Moody - Managing Director 01722 414 419

Aquila Financial Ltd www.aquila-financial.com
Peter Reilly 020 7202 2601


Notes to editors

www.rockhopperexploration.co.uk

Rockhopper Exploration plc commenced trading in February 2004 to invest in and
carry out an offshore oil exploration programme to the north of the Falkland
Islands. The Company, floated on AIM in August 2005, is currently the largest
licence holder in the North Falkland Basin and has a 100 per cent. interest in
four offshore production licences which cover approximately 5,800 sq. km. These
licences have been granted by the Falkland Islands government.




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