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HMRC internal manual

Oil Taxation Manual

The taxation of the UK oil industry: an overview: early activity in the North Sea

There were initially four rounds of offshore licensing in 1964, 1965, 1969 and 1971. Encouraged by geological reports, the major oil companies moved into the North Sea to explore for natural gas. By Christmas 1964 one of the first drilling rigs was at work and by 1969 approximately 180 wells had been drilled and 5 major gas fields discovered.

Although the gas was valuable the real target was oil. The first oil was found in 1967 in the Arbroath Field. Then in June 1970, the Ekofisk Field was discovered in the Norwegian sector of the North Sea followed by the Forties Field in October 1970.

By 1973 a significant number of discoveries had been made in the UK North Sea.