Over a long transitional period, oil and gas will be of crucial global significance for continued economic growth and security of energy supply, while the proportion of energy from renewable sources is increasing and becoming cost-effective. Oil and gas from Danish fields are therefore also part of the Government's Energy Strategy 2050.
GEUS’ activities in brief
GEUS is the key advisor for the Danish authorities. Furthermore, GEUS works closely with the oil industry on research and consultancy that can provide incentives for further investments in exploration and production.
The majority of Danish oil and gas resources are found in chalk fields in the Danish Central Graben in the North Sea.
For many years now, GEUS has been working to expand our knowledge about these chalk fields. This work includes a plethora of geological studies aimed at understanding the composition of the geological layers, their structure and where to expect oil and gas deposits. Furthermore, our aim is to gain geological insight into the formation of the high-porosity chalk layers from which oil today is pumped up. Efforts include surveys of the flow of oil in the low-permeable chalk and they contribute with knowledge about the production properties of the chalk and the stability of extraction wells in heavily fractured chalk.
The majority of Danish oil and gas production takes place from the uppermost parts of the chalk group. In recent years, GEUS has been working on an assessment of whether there is additional potential for discoveries in other layers of the chalk group, as well as an assessment of the potential in the deep, clastic layers where exploration wells in the North Sea have documented considerable hydrocarbon deposits.
This work includes the development of tools and geological models to predict the distribution and the properties of the deeper-lying clastic reservoirs.
Research efforts by GEUS contribute to identifying the location of new deposits of oil and gas, but they also contribute to developing methods to improve oil recovery from existing chalk fields. The possibilities for enhancing oil recovery from the North Sea include studying how an oilfield reacts if reservoirs are injected with CO2, for example.
In connection with licensing rounds in the North Sea, GEUS evaluates the quality of applicants' work programmes and prepares memoranda for the Danish Energy Agency. Furthermore, GEUS markets an extensive series of geodata and offers industry data compilations.
Internationally, for many years GEUS has been involved in large regional oil-geological compilations e.g. in the form of atlases, and GEUS is contributing to the build-up of research expertise in several countries, including in Vietnam.
Enhanced oil recovery
The North Sea chalk, from which oil is being pumped up, is very fine-grained, which makes it difficult to retrieve the oil from the small cavities. Methods and techniques for extracting oil from the chalk have become evermore sophisticated over the years that oil production has been in operation. Much more of the oil can now be pumped up than at the start. The new, sophisticated production techniques which the oil companies have developed include horizontal wells and water injection.
These new techniques place great demands on our knowledge about chalk formation and stratification; knowledge GEUS has helped generate over many years. Today, GEUS is taking part in studies of whether more oil can be recovered from the North Sea by pumping CO2 down into the reservoirs. The CO2 makes the oil less viscous to facilitate the flow towards the production wells.