Early history of petroleum exploration offshore Norway and its impact on geoscience teaching and research

The Norwegian government and also the universities were unprepared for an offshore oil province. Very little information about the offshore geology was then available due to the thick cover of Quaternary and Tertiary sediments in the North Sea basins. The potential for oil and gas in the North Sea could not have been predicted before the Norwegian Continental Shelf (NCS) was opened for petroleum exploration and drilling in 1965. Statements from the Geological Survey of Norway (NGU) in 1958 that there was no potential for oil offshore Norway referred specifically to the coastal areas, where no oil has been found. The midline principle was introduced in 1964, through an agreement with the UK. A continental shelf committee led by Jens Evensen from 1963 to1965 prepared the legal aspects and the regulations applicable for oil companies applying for licences to explore and produce oil and gas offshore Norway. A proposal for a Norwegian petroleum-related research project in 1964 was not funded and it took several years before petroleum-related teaching and research were established. After several dry wells the Ekofisk Field was discovered late 1969–early 1970, making it clear that Norway would become a significant oil-producing country. However, at that time nearly all the expertise was inside the major international oil companies and petroleum-related research at Norwegian universities and research institutes had a slow start. In 1972, Statoil and the Norwegian Petroleum Directorate (NPD) were established and also government funding for petroleumrelated teaching and research. This was met with considerable scepticism and resistance from some students and faculty and some claimed that a general education in geology would be sufficient. The University of Bergen developed a strong research group in marine geophysics and later one in petroleum geology. The need for petroleum-related teaching and research created a great challenge for the Norwegian universities. The standard was variable and the output of graduates with a professional qualification was generally too low. What we know about sedimentary basins and many fundamental geological processes is the result of petroleum prospecting and data from drilling and seismic data, contributing to Norwegian geology and general geological principles

Experimental calcite dissolution under stress: Evolution of grain contact microstructure during pressure solution creep

International audienceFor the first time, nanometer resolution techniques both in situ and ex situ were compared in order to study calcite dissolution under stress. The obtained results enabled identification of the relative importance of pressure solution driven by normal load and free surface dissolution driven by strain energy. It is found that pressure solution of calcite crystals at the grain scale occurred by two different mechanisms. Diffusion of the dissolved solid took place either at a rough calcite/indenter interface, or through cracks that propagated from the contact toward the less stressed part of the crystal. It is also found that strain rates are mostly a function of the active process, i.e., pressure solution associated or not with cracks, rather than being influenced by stress variations. Strain rates obtained in this study are in agreement with published data of experimental calcite and carbonate dissolution under stress