The Dutch economy will remain dependent on gas for the next decades. In order to reduce dependency on countries outside of the EU, exploration efforts within the Netherlands and neighboring countries will have to continue. An accurate understanding of the structure of the deep subsurface is crucial when it comes to the development of models that facilitate the exploitation of hydrocarbons and geothermal energy.
A remarkable observation is that the Lower Jurassic deposits of the Netherlands are not considered as a prospective target for gas exploitation, with the exception of the Early Toarcian Posidonia Shale Fm. (PSF). Because of its proliferous source-rock properties, there is extensive knowledge regarding the distribution of the Posidionia Shale Formation. Its deposition is limited to Mesozoic rift basins. It is often assumed that its absence elsewhere is a consequence of erosion during subsequent phases of tectonic activity.
An alternative hypothesis however maintains that deposition of this important source rock was in fact confined to limited areas of such basins. This implies that strong lateral environmental heterogeneity affected the depositional settings and potential resource distributions. This may also imply that other Lower Jurassic strata such as those of the Sleen, Aalburg Formation and the Werkendam Formation also have potential for the presence of gas source and reservoir rocks. This is illustrated by considering the geology of adjacent countries. In the UK, Germany and Denmark there is a much more extensive understanding of the Lower Jurassic depositional system, mainly because the presence of outcrops and shallower burial depths of the deposits. This implies that also in mature basins, new and refined play concepts can be identified in the depositional systems of the Lower Jurassic. This however requires enhancement of the geological model of the basin by means of data-inventories and the application of innovative techniques aimed at constraining changes in the depositional environment, stratigraphy and structural development of the basin.
This warrants an extensive regional-scale stratigraphic study aimed at detecting prolific areas and intervals by establishing a good understanding of the paleogeographic evolution of the basin. To this end, we propose to employ and further develop integrative and innovative bio- and chemostratigraphic techniques, in close collaboration between TNO, EBN and operators. A summary of the project is provided by the following illustration.
The proposed study aims to elucidate the geological development of the Lower Jurassic in relation to the hydrocarbon system development. To this end we propose to employ and further develop integrative and innovative bio- and chemostratigraphic techniques, in close collaboration between TNO and operators. The results will compliment various other multipartner projects and those of the operators.
The study will result in a written report comprising directly implementable products like correlation panels, a new tectonostratigraphic framework en paleogeographic maps. Two innovative aspects of the study will result in two peer-reviewed scientific publications. Overall, the study will provide important new insights for the development of new play systems and will meanwhile target new areas for hydrothermal energy exploitation.