Extended Abstract for presentation at EAGE Meeting Paris 13/ History of Norwegian Petroleum Exploration and its impact on Norwegian Geosciences

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1 Extended Abstract for presentation at EAGE Meeting Paris 13/ History of Norwegian Petroleum Exploration and its impact on Norwegian Geosciences Knut Bjørlykke University of Oslo Abstract Before petroleum exploration in Norway started in 1965, geology was mostly an academic discipline with few professional geologists. The mining industry was in decline and did not contribute much to research in Norway. The Norwegian offshore was opened for exploration in 1965, but its potential for oil and gas could not be predicted before the first well was drilled in The detailed history of the Norwegian shelf and the petroleum production and exploration is available from the Norwegian Petroleum Directorate (npd.no). The discovery of the Ekofisk Field in 1970 made it clear that Norway would become a major oil producing country. From 1971 the government introduced a special funding for petroleum related teaching and research in Norway and this was also supported by oil companies. A national oil industry and petroleum policy required an independent expertise in geology, geophysics and engineering. Petroleum related research reached a high level in many disciplines. There was a massive recruitment of geoscientists from Norway and from abroad. Oil production peaked in 2002, but oil and gas production is still high. Petroleum related geoscience in Norway has strengthened other geoscience disciplines and also fundamental research. In recent years environmental geology and storage of CO 2 have become important.

2 26/ History of Norwegian Petroleum Exploration and its Impact on Norwegian Geosciences. Knut Bjørlykke, Department of Geosciences. University of Oslo. Introduction We like to admire fundamental research, and so called curiosity driven research has had the highest prestige at most universities. However, curiosity may be stimulated and increased when faced with practical problems. The need to know and understand how to solve practical and technical challenges may be an inspiration for penetrating more deeply into scientific problems. The geological sciences are built mostly on other sciences, mainly physics, chemistry, mathematics and biology. Geology has had many practical applications, and particularly the mining industry required advanced knowledge of mineralogy and chemistry and also special technology. Historically the mining industry was the most important example of applied geology, mineralogy and chemistry. Mining Academies were set up in many parts of Europe and elsewhere. In Norway Bergakademiet in Kongsberg started in 1754 and was the main institution for higher learning before the University of Oslo was established in At the University of Oslo mining geology and mineralogy made up a large part of the science faculty and its students from the start in 1811, because the mining industry was one of the few employers of geologist and chemists. The Geological Survey of Norway (NGU) was founded in 1858 in order to map the bedrocks of Norway, as part of the exploration for ore and minerals to be mined. At the University of Oslo mining geology and chemistry could be studied as a special discipline up to 1913 when this was continued at the newly established University in Trondheim (NTH, NTNU). Professor J.H.L. Vogt was appointed professor of metallurgy at the University of Oslo (Kristiania) and continued in Trondheim. The University of Oslo had, led by V. M. Goldschmidt, a very strong tradition in geochemistry and mineralogy, but the results in terms of practical applications were rather limited. The mining industry in Norway did not employ many geologists, mainly mining engineers and there were few other jobs for geologists. In 1958 there were in total only about 60 professional geologists in Norway, comprising geologists at the universities and governmental institutions like the Geological Survey (NGU), Polar Institute, etc. As a result geology was a subject for those with very special interests with poor job prospects. Early Exploration in the North Sea Up to about 1965 the geology of the Norwegian Continental Shelf (NCS) was almost unknown. Plate tectonic theory was just evolving and it took some time before it was applied to North Sea geology. There was no agreement about the extent of Norway s continental shelf before 1964 when a midline between Norway and Britain was established. Hence, there was no basis for predicting the oil and gas potential of the North Sea Basin and the rest of Offshore Norway. At a Conference in Geneva in 1958 it was suggested that each country had sovereignty from the coastline to 200 m water depth. The glacially eroded deep Norwegian Trench could then be considered

3 to be the limits of the Norwegian shelf. A statement from the Norwegian Geological Survey (NGU) in 1958 concluded that there was little possibility of finding oil on the Norwegian shelf. This was however a reasonable judgement based on what was known about the geology of the judicial Norwegian shelf at that time. It was known that Mesozoic sedimentary rocks onshore Denmark and England extended into the North Sea Basin, but not how far. However, some evidence indicated that such sediments were present very close to the Norwegian Coastline. Onshore drilling in Denmark in found Mesozoic and Upper Palaeozoic sediment, but did not find oil. The discovery of the Groningen Gas Field in 1958 caused an interest in the North Sea Basin as an oil and gas province. Even when it was established, through early seismic surveys, that the North Sea Basin contained a thick sedimentary succession we knew very little about the possibility for oil and gas. In 1964 Britain and Norway agreed on the midline principle dividing the territories for North Sea Exploration. In much of the North Sea Basin, both offshore Norway and Britain (Yorkshire), the Upper Jurassic Kimmeridge black shale was immature. But due to late Jurassic rifting and subsidence it was buried deeply enough to be mature in the central part of the North Sea Basin close to the mid line between the British and Norwegian shelf. Hence, the distribution of the Upper Jurassic Kimmeridge Clay (Draupne Fm, Mandal Fm, Spekk Fm) and its burial depth (maturation) was critical. The Geological Survey (NGU) played a role in the preparation for the opening of the continental shelf and published in 1965 a magnetic residual map offshore mid-norway showing the depth to basement, indicating thick sedimentary sequences. Petroleum activities were later administrated by the Norwegian Oil Directorate (NPD) After drilling of the first well in 1966 we knew that the North Sea Basin had a succession of Upper Jurassic shales, with a high content of organic matter, serving as the main source rock for most of offshore Norway. This provided a better basis for prediction of the oil and gas potential. However, it was only in 1970 that the first discovery (The Ekofisk Field) was accidentally made in upper Cretaceous chalk whilst drilling for prospects in the Permian sandstone and salt strata. Petroleum related Education After the discovery of oil on the NCS, petroleum related education and research was required in Norway. In the early stages the introduction of this new discipline was met with considerable skepticism. At some universities, there was a conflict between what was considered basic science and what was considered applied industry related research. An academic ideal was that university professors should be able to study any subject relating to the processes in the earth crust and the evolution of life on earth. It was argued by some that a general introduction to geology and geological processes was also the best background for solving practical problems and industrial applications. But it was soon realized that a more professional training in petroleum related disciplines was necessary. Petroleum related education and research not only met the needs of the oil industry, but also produced new data and knowledge relevant to the geology of Norway and strengthened the general importance of geological disciplines in the public domain. Norwegian geologists argued that Norwegian oil policy should not depend on international oil companies, and required our own expertise when advising the politicians. Petroleum exploration and production Offshore Norway - Providing data for the study of geological processes in sedimentary basins.

4 Geological studies were traditionally based on mapping and studies of outcrops in the field. The rock properties observed had then to be interpreted based on a poorly constrained burial history and uplift. Offshore Norway contains a nearly complete succession of Upper Paleozoic, Mesozoic, and Neogene sediments. In the North Sea Basin sediments could be studied at varied burial depths and also followed laterally based on well data and seismic sections. The development of new geophysical methods have contributed to our understanding of the plate tectonic origin and structural framework of the NCS, fundamental processes related to the development of sedimentary sequences and their depositional history, basin formation and architecture and structure of petroleum traps. Diagenetic processes could be studied based on data from sediments at shallow burial to great depths. Prediction of the porosity in sandstones changing from loose sand to tight sandstones due to mechanical and thermally driven chemical compaction was important for the quality of sandstones reservoirs. New insight into controls on porosity, permeability and fluid flow in siliciclastic sediments has been developed in close cooperation between research groups at universities and the petroleum industry. Soft clays and mudstones could be followed through different stages to hard and fissile shales. Natural compaction in sedimentary basins could be compared with experimental compaction measuring porosity loss and velocity (Vp,Vs). Research on the properties of sandstones and shales became very critical because of their potential role as reservoir rocks, cap rocks and source rocks. The composition of oil and gas in relation to source rocks have helped reconstruction of oil migration. In recent years electromagnetic methods have also been used in exploration. A large number of wells have been drilled offshore Norway. Cores, cuttings, seismic and log data are stored by the Norwegian Oil Directorate. This provides a unique data base for further research. Oil production on the Norwegian Shelf peaked in 2002 at about 3.0 mill barrels/ day. Since then oil production had declined to mill barrels per day, but the gas production has increased, so that the production is presently nearly 4.0 mill barrels of oil equivalents /day. Major new discoveries have been made in recent years (notably the Johan Sverdrup field with billion barrels o.e.) Academic geology has had a tendency to specialize into narrow disciplines both in terms of teaching and research. The applied nature of petroleum exploration and production requires more synthesis with respect to disciplines and also methods. The petroleum industry has for 50 years been the major employer of geoscientists in Norway, thus making it possible to maintain strong teaching and research programs at the universities. This has provided a basis both for applied and basis geoscience research. The petroleum industry in Norway has been a major factor in the Norwegian economy despite varying oil prices. The oil industry has employed several thousand geologists and geophysicist s. Despite the recent drop in oil prices the total petroleum revenue for 2015 was 215 billion NOK (down from 312 billion in 2014). The share of Norway s GDP was 15%. It was 20% of the State`s revenue, 26% of the total investments and 40% of the of total export. Since the start in 1972 petroleum activity has contributed more than billion in current NOK to the GDP. So far less than 50% of the estimated recoverable resources have been produced. It is also worthy of note that environmental problems and major oil spills have been limited in the 50 years of petroleum exploration on the Norwegian Shelf. Norway will probably be able to produce oil and particularly gas for many years in the future. Much of the gas is piped to Europe The potential for some of the produced reservoirs to store CO 2 is now the subject of important research projects.

5 Although there are many other important geological disciplines also in Norway, the number of geoscientists would have been rather small without a petroleum industry. It can be concluded that the petroleum industry has had a great impact on development and status of geosciences in Norway.. Upper Jurassic rifting and Tertiary sea floor spreading. Important for maturation of source rocks (Kimmeridge Clay) From Faleide et al Up Fig 1Bathymetry offshore Norway Rifting Phases Late Cret. Late Jurassic Late Paleozoic Fig 2. Main structural elements

6 Fig 3. The rate of resource growth from the beginning of petroleum exploration in 1967 List of references. Faleide, J.I., Bjørlykke, K. and Gabrielsen R., 2015.Geology of the Norwegian Continental Shelf, In Bjørlykke K. (Ed) Petroleum Geoscience: from Sedimentary Environments to Rock Physics. Springer Verlag 662 p. Rønnevik H.C., Exploration Strategy. In Bjørlykke, K. (Ed) Petroleum Geoscience: from Sedimentary Environments to Rock Physics. Springer Verlag, 662 p.

7 Norways petroleum history. Norwegian Petroleum Directorate. (