Rockhopper Regulatory News (RKH)

2 April 2015

Rockhopper Exploration plc

("Rockhopper" or the "Company")

14/15b-5 Well Update

Oil and Gas Discovery

Rockhopper Exploration plc (AIM: RKH), the oil and gas exploration and production company with interests in the North Falkland Basin and the Greater Mediterranean region, is pleased to provide the following update on the Zebedee Exploration well 14/15b-5 (the "Well").

Highlights

· 25.3m net oil pay in Zebedee

· 18.5m net gas pay in Hector

· Additional oil bearing F2 sand with 2.6m net oil pay

The Well is located on licence PL004b in which Rockhopper has a 24% working interest. The Company can confirm that all seven of the reservoir targets predicted across the Cretaceous F1-F3 intervals were encountered. An additional sand was also encountered in the F2 sequence. Three of the sands were hydrocarbon bearing at this location, including the primary Zebedee F2 fan and additional oil shows were recorded in the deeper F3 targets.

Wireline logging and formation test data indicate that a total of 18.5m of net gas pay, and 27.9m of net oil pay were encountered in the Well.

Hector

The Hector sand was encountered on prognosis near the crest of the structure and penetrated a gross reservoir package of 27.6m. Net gas pay was 18.5m and initial indications are of good reservoir properties.

No gas oil contact was observed, and pressure data indicates that the gas gradient is offset from the gas gradient observed previously in the Beverley and Casper South reservoirs. Hector therefore may be oil bearing in a downdip location (the Hector 'oil rim').

Zebedee

The Zebedee sand was encountered on prognosis, penetrating a gross reservoir package of 29.3m with net oil pay of 25.3m. This reservoir was the principal target of the Well, and proves the presence of a further fan system to the south of Sea Lion and the previously discovered satellites.

The reservoir quality is amongst the best encountered to date.

No oil water contact was observed in Zebedee.

Additional F2 sand (Ninky South)

In addition to the two principal reservoirs a further F2 reservoir was encountered above the Zebedee fan at 2436.6m measured depth and is also oil bearing. The Well gross reservoir thickness was 6.4m and net oil pay was 2.6m. The sand, which Rockhopper currently map to form part of Ninky South, was tagged in a very marginal position and was not therefore included in the pre-drill stack prognosis.

Good oil shows were also recorded at the deeper F3 targets but at this location the sands are not well developed.

The Well will now be plugged and abandoned as a successful exploration well. The Eirik Raude rig will then drill the first exploration test on the Elaine/Isobel fan complex in the southern part of the North Falkland Basin with the Isobel Deep well. The results of this well are expected in late April 2015 and a further announcement will be made upon spudding on the well.

Samuel Moody, CEO, commented: 

"This is a fantastic start to the 2015 Falklands drilling campaign and provides early proof of the significant remaining potential of the North Falkland Basin. In addition to the new discoveries at Zebedee and Hector, we have good oil shows throughout the deeper F3 section which is encouraging should better quality reservoir be encountered in this section elsewhere in the basin. Having retained the sub-surface lead for North Falkland Basin exploration in the farm out to Premier in 2012, I am delighted to report that our exploration team now enjoys a success rate of 8 out of 10 wells in licences PL004 and PL0032. The new discoveries add to our already significant resources we have discovered in the basin and we now look forward to drilling the higher risk Isobel prospect before the rig moves to drill in the South Falkland Basin."

For further information, please contact:

Rockhopper Exploration plc

Tel: (via Vigo Communications) - 020 7016 9571

Sam Moody - Chief Executive

Fiona MacAulay - Chief Operating Officer

Stewart MacDonald - Chief Financial Officer

Canaccord Genuity Limited (NOMAD and Joint Broker)

Tel: 020 7523 8000

Henry Fitzgerald-O'Connor

Liberum Capital (Joint Broker)

Tel: 020 3100 2227

Clayton Bush

Vigo Communications

Tel: 020 7016 9571

Peter Reilly

Patrick d'Ancona

Note regarding Rockhopper oil and gas disclosure

This announcement has been approved by Rockhopper's geological staff who include Fiona MacAulay (Chief Operating Officer), who is a Fellow of the Geological Society of London and a Member of the Petroleum Exploration Society of Great Britain and American Association of Petroleum Geologists with over 25 years of experience in petroleum exploration and management, and who is the qualified person as defined in the Guidance Note for Mining, Oil and Gas Companies issued by the London Stock Exchange in respect of AIM companies. In compiling its resource estimates, Rockhopper has used the definitions and guidelines as set forth in the 2007 Petroleum Resources Management System approved by the Society of Petroleum Engineers.