Multiscale seal characterization in the North Sea Implications from clay sedimentology, well logs interpretation and seismic analyses

Abstract

This PhD aims primarily to assess the long-term sealing capabilities of shaly seal rock units overlying potential adequate CO2 storage reservoirs. The motivation for the project has been that in order to reduce CO2 emissions and climate change. Geological Storage of CO2 should be evaluated as a possible major mitigation action. In this study, acoustic and petrophysical properties of ten exploration wells in the Egersund Basin area were utilized in order to investigate compaction. Scanning Electron Microscopy (SEM) and X-Ray Diffraction (XRD) analyses from selected wells and available total organic carbon (TOC) data were used to interpret the compaction processes and resulting rock properties. Uplift and erosion were also addressed. The petrophysical implications of source rock microfracturing of organic-rich shales as well as the effect of diagenesis on pore pressures in fine-grained rocks were studied. In addition, the pre-Zechstein structural grain and its influence on the development of the Egersund Basin area were addressed.