ABSTRACT The objective of this study was to investigate the geological controls on stratigraphic and lithologic variability in the Ordovician Utica Shale and related Collingwood Member in the Michigan Basin in order to assess CO 2 sequestration cap rock (seal) potential, including petrophysical properties and mechanical fracture responses. Twelve conventional cores and hundreds of modern well logs from the Michigan Basin were analyzed to correlate and calibrate wireline log signatures with whole-rock mineral composition (from X-ray diffraction analysis) and mechanical properties (from core analysis) to identify brittle, fracture-prone zones, and to validate the Utica Shale as a regional geologic seal. Analysis using scanning electron microscopy with Quantitative Evaluation of Minerals by Scanning Electron Microscope (QEMSCAN ® ) software was employed to image pores and for quantitative analysis of mineralogy, texture, and porosity. Mercury injection capillary pressure and triaxial strength testing was conducted to assess petrophysical properties and mechanical responses. The results suggest the Utica Shale could reliably contain upwards of 1500 m of buoyant, supercritical CO 2 stored in underlying Cambrian and Ordovician reservoirs.

Abstract A detailed 3D petroleum system model was constructed for the Schleswig-Holstein area in northern Germany. Salt movement and the Quaternary ice episodes were implemented in order to reconstruct their impact on temperature, maturity and pressure. Burial, temperature and maturity histories were calculated for the Jurassic troughs and the Glueckstadt Graben showing both differences and similarities. For example, all locations reached (almost) deepest burial at present day, whilst subsidence and long-term sedimentation rate was highest in Glueckstadt Graben during the Triassic. The Jurassic troughs received their major subsidence and sedimentation pulse later, and were strongly affected by a later salt movement. The implementation of Quaternary glacial episodes does not have a strong impact on petroleum generation from the major source rock (Lower Toarcian Posidonia Shale). In the case of the Posidonia Shale reaching the stage of petroleum expulsion (outside of the study area), the effect of ‘glacial pumping’(i.e. the development of high pore pressures during glaciation followed by expulsion and subsequent pressure release during deglaciation) can be deduced from the model. Petroleum accumulations in the reservoir layers (Dogger sandstones) are also seen to have been affected. This finding is of interest for exploration, as it might control petroleum composition, biodegradation and leakage through cap rocks.