26 August 2015

Doriemus plc

("Doriemus" or the "Company")

Schlumberger Independent Assessment of Horse Hill Licence Area

The Board of Doriemus plc (AIM: DOR) announces that a mean Oil in Place (“OIP”) of 10.993 billion barrels has been independently calculated by Schlumberger to lie within the 55 square miles of the PEDL137 and PEDL246 Horse Hill licences (”the Licence Area”) in the Weald Basin, located in the South East of England. Doriemus has a net attributable interest of 6.5% in the Licence Area.

The tight Jurassic limestones and shales of the Kimmeridge Clay Formation in the Licence Area are calculated to contain a total OIP of 8.262 billion barrels, with the shales of the Oxford Clay and Lias Formations containing an aggregate OIP of 2.731 billion barrels, as shown in Table 1.

Table 1: Licence Area mean OIP estimates, millions of barrels (“MMBO”)

Schlumberger acquired the Horse Hill-1 well (“HH-1”) electric logs during the drilling of HH-1. This analysis builds on their previous petrophysical evaluation of HH-1, located in PEDL137 near to London Gatwick Airport, as announced on 5 June 2015. In that previous HH-1 analysis, a total mean OIP, excluding the Upper Portland sandstone oil discovery, of 255 million barrels of oil per square mile was calculated. The current report incorporates the analysis of a further nine wells located within and beyond the Licence Area.

It should be noted, as previously reported, that the HH-1 Upper Portland sandstone oil discovery is a geologically separate oil accumulation from, and additional to, the identified underlying Jurassic tight oil plays.

As previously stated by the Company, the above estimated OIP hydrocarbon volumes should not be construed as recoverable resources or reserves and also should not be construed in any way to reflect potential producibility of hydrocarbons from the formations evaluated. The Company would expect to report estimated recoverable resources following a successful well flow test, in order to comply with the standards of the Society of Petroleum Engineers’ 2007 Petroleum Resources Management System.

The report’s findings will now be integrated into the planned flow test of HH-1 expected later this year, subject to approval by the Environment Agency. This is another key step in the proof of concept process for Jurassic tight oil and the Kimmeridge limestone reservoirs in particular.

Additional internal and external technical studies are now well advanced in order to fully understand the possible implications of the report’s key findings upon the hydrocarbon potential of the Weald Basin.

Donald Strang, Doriemus’ Chairman, commented:

“Schlumberger’s report for the HH licences has calculated OIP 19% higher than Nutech’s equivalent OIP estimate. These two specialist companies have therefore independently confirmed the significance of the tight oil Jurassic resource play in the Weald Basin As with Nutech’s analysis, Schlumberger used a number of wells in the Weald Basin in deriving their estimate. Doriemus looks forward to moving ahead with the planned Horse Hill-1 flow test.”

Future Plans:

In parallel with its subsurface and HH-1 flow test studies for the Portland sandstone and underlying tight Jurassic oil zones, related engineering and environmental studies have been commissioned to investigate a conceptual Weald Jurassic field development, with the prime objective that it must respect and preserve the rural beauty and way of life of the area, with minimal environmental impact, while at the same time providing a valuable contribution to the area’s economy.

 Doriemus’ interest in the Licence Area and Horse Hill:

The Licence Area, comprising licences PEDL137 and PEDL246, is located on the northern side of the Weald Basin of South East England near Gatwick Airport. The HH-1 discovery well is located in PEDL137. Doriemus owns a 10% direct interest in Horse Hill Developments Ltd ("HHDL"). HHDL is a special purpose company that owns a 65% participating interest and is the operator of the Licence Area. The remaining 35% participating interest in the Licence Area is held by Magellan Petroleum Corporation.

For further information please contact:

Doriemus plc

Donald Strang / Hamish Harris                                                                         Tel: 020 7440 0640

Cairn Financial Advisers LLP

James Caithie / Sandy Jamieson / Carolyn Sansom                                          Tel: 020 7148 7900

Square 1 Consulting (Public Relations)

David Bick / Mark Longson                                                                              Tel: 020 7929 5599

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