In the late 1950s, very few people believed that the Norwegian continental shelf (NCS) might conceal rich oil and gas deposits. However, the discovery of gas at Groningen in the Netherlands in 1959 caused people to revise their thinking on the petroleum potential of the North Sea.
The Groningen discovery led to enthusiasm in a part of the world where energy consumption to a large extent was based on coal and imported oil. In the eagerness to find more, attention was drawn to the North Sea. Norway’s geological expertise was negative to oil and gas deposits, but this could not stop the enthusiasm after the gas discovery in the Netherlands.
In May 1963, Norway’s government proclaimed sovereignty over the NCS.
Even though Norway had proclaimed sovereignty of large offshore areas, some important clarifications remained on how to divide the continental shelf, primarily with Denmark and Great Britain. Agreements on dividing the continental shelf in accordance with the median line principle were reached in March 1965. First licensing round was announced on 13 April 1965. 22 production licences for a total of 78 blocks were awarded to oil companies or groups of companies. The production licences gave exclusive rights for exploring, drilling, and production in the licence area.
On July 19, 1966, the operator ExxonMobil spudded the first well to be drilled on the Norwegian Continental Shelf.
ExxonMobil had chartered the drilling semi-submersible Ocean Traveler owned by the leading offshore drilling company ODECO.
It took up to 52 days to the Ocean Traveler to cross the Atlantic on a wet tow from Louisiana. The Unit arrived in Dusavik near Stavanger in June 1966. The Ocean Traveler was built at the Avondale Shipyard in New Orleans. Although it was a brand new rig, the Norwegian authorities found several faults with it which had to be repaired before drilling could begin.
The well 8/3-1 came dry but better days came. The Ocean Traveler struck oil at the 25/11-1 well located at 190 km west of Stavanger on July 19, 1966. However, it was not considered to be economically viable at the time, and it took another 30 years before the field was finally developed.
The first oil discovery on the Norwegian shelf was Balder in 1967. However, it was not considered to be economically viable at the time, and it took another 30 years before the field was finally developed.
Just before Christmas in 1969, Phillips informed the Norwegian authorities of the discovery of Ekofisk by the Ocean Viking, which turned out to be one of the largest offshore oil fields ever discovered. This was when Norway’s success story started in earnest. Production from the field started on 15 June 1971. A series of major discoveries was made in the next few years.
Ocean Traveler had big problems with the weather conditions in the North Sea, the weather being much tougher in the North Sea than the areas off the southern coast of the United States. These experiences laid the foundation for the sister platforms, especially the Norwegian-built “Ocean Viking”, which had a significantly strengthened structure.
• 1966 – First well spudded offshore Norway
• 1967 – First oil discovery at Balder
• 1971 – Ekofisk and Frigg
• 1972 – Heimdal
• 1974 – Statfjord
• 1978 – Gulfaks
• 1979 – Oseberg
• 1981 – Asgard
• 1983 – Troll
• 1984 – Snohvit
• 2010 – Johan Sverdrup
In these early days of oil exploration off Norway, the number of vessels suited to the conditions of the high latitudes of the north sea was limited. The most active were the following:
• Ocean Traveler (Semi-submersible)
• Ocean Viking (Semi-submersible)
• Glomar Grand Isle (Drillship)
• Neptune 7 (Semi-submersible)
• Sedneth 1 (Semi-submersible)
• Orion (Jackup)
• Gulftide (Jackup)
(Source: Industrial Heritage Ekofisk/Norske Petroleum/NPD/Government.no – Image: Ocean Traveler/ExxonMobil)