In 2006 Ophir recognised that access to deepwater rigs was a potential risk to the Company's ability to execute its planned exploration programme and so made a strategic decision to gain access to deepwater drilling rigs.

The Company subsequently entered into rig sharing agreements with ExxonMobil Corporation's (ExxonMobil) drilling subsidiary, Esso Exploration Incorporated (Esso) and Seadrill Offshore A/S (Seadrill) to provide access to the ultra-deepwater dynamically positioned drillship (DPDS) West Polaris. At the same time Ophir has built a strong drilling team which is capable of operating a multi-well drilling campaign in the deepwater settings where the Company has assets. This capability is regarded as one of Ophir's strengths and allows the Company to control the pace of exploration in those assets it operates in.

A further series of agreements with Esso and Larsen Oil & Gas Limited, on behalf of Venture Drilling A/S, gave Ophir access to a second rig, the DPDS, Deep Venture in 2008. Ophir used this rig on its first operated drilling campaign which focused upon the Company's assets in Equatorial Guinea and Gabon.

In June 2010 Ophir signed a three well contract with Odfjell Drilling to utilise the new build, harsh environment, ultra deepwater, dynamically positioned semi submersible rig Deepwater Stavanger. This rig will be used to drill Ophir's first exploration wells in the Tanzania PSCs and drilling is expected to commence in September 2010.

In July 2010 Ophir signed a one well contract with A.P. Moller-Maersk A/S to use the newly built (June 2010) ultra deepwater semi Maersk Deliverer. This rig will be used in conjunction with other operators as part of a north-west African sequence to drill the ultra deepwater prospect Kora in the JDZ between Senegal and Guinea Bissau the AGC.

Ophir's portfolio is predominantly in either deep (500m to 1,000m) or ultra deep (>2,000m) water depths. To explore effectively, Ophir has had to develop several capabilities and technologies to meet the challenges of exploring in such extreme environments. In order to drill safely and cost-effectively Ophir has developed a strong capability for rock pore pressure modelling techniques to optimise well design. This, together with a proven ability to operate in remote locations, allows Ophir to deliver world class drilling operations in any of its assets.

In 2008 Ophir was able to drill five wells (including two discoveries) in less than 100 days, drilling in two countries (Gabon and Equatorial Guinea). To achieve this type of performance Ophir utilised the "Technical Limit" approach to drilling planning. This concept takes a bottom up approach to what is possible in an ideal case (ie the technical limit) and the planning process then focuses on what issues would prevent good performance. It then engineers solutions to each one in order to minimise the impact on the operation. This technique was first developed in the mid 1990s and has proved effective in many parts of the world.

In addition to accessing suitable drilling rigs at a time when world demand for deepwater rigs exceeded supply, Ophir has utilised innovative technologies such as Surface BOPs (SBOP) to extend the water depth capabilities of shallower water rigs.

Conventionally the Blow Out Preventer (BOP) on a floating vessel is placed at the seabed and connected to the rig by a low pressure riser to allow mud returns to the rig. SBOP is a technology that allows the use of two BOPs, one at the seabed and a second at surface connected by a high pressure riser. The advantage this gives is the weight of the system is significantly reduced which, since the water depth capability of a rig is normally controlled by the tensioner's capability that support the riser, reducing riser weight allows more riser to be run. Ophir safely and successfully utilised this technique in Gabon and Equatorial Guinea in 2008 to accelerate drilling significantly by using a rig that could not drill the required water depths conventionally.

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