Oilfield services company Schlumberger has independently calculated a mean Oil in Place (OIP) of 10.993bn barrels to lie within the 55 square miles of the PEDL137 and PEDL246 Horse Hill licences in the Weald Basin.

UK Oil & Gas Investments (UKOG) holds a net attributable interest of 20.358% in the licences, located on the northern side of the Weald Basin of South East England near Gatwick Airport.

According to UKOG, the tight Jurassic limestones and shales of the Kimmeridge clay formation in the licences are calculated to contain a total OIP of 8.262 billion barrels.

"The report is a further step towards establishing proof of concept for the Jurassic tight oil play potential of Horse Hill and the Weald Basin."

The shales of the Oxford Clay and Lias formations consist of an aggregate OIP of 2.731bn barrels.

The Horse Hill-1 well (HH-1) electric logs were acquired by Schlumberger during the drilling of the HH-1 discovery well located in PEDL137.

UKOG’s latest report incorporates the analysis of a further nine wells that are located within and beyond the licences.

UKOG chairman Stephen Sanderson said: "The independent analysis has further tested and given support to our geological model, which predicts that the significant volumes of OIP calculated within the tight Jurassic section of HH-1 extend across the Licence Area.

"The report is thus a further step towards establishing proof of concept for the Jurassic tight oil play potential of Horse Hill and the Weald Basin."

Earlier, the company said that the above estimated OIP hydrocarbon volumes should not be construed as recoverable resources or reserves.

The company will integrate the report’s findings into the planned flow test of the HH-1 well expected later this year.