Maturity modelling of selected wells in the central North Sea

This report details maturity and migration modelling of selected wells in the UK Central North Sea for the 21CXRM Palaeozoic project. The aim of the maturity and migration modelling was to predict if Carboniferous-Devonian source rock intervals are, or have been, mature for hydrocarbon generation around the Mid North Sea High (MNSH) region and to examine the timing and possible migration routes of any generated hydrocarbons. Modelling data selection and main expected plays Eight wells were chosen for 1D modelling based on availability of data and the location of the wells such that the models would contribute to understanding the thermal maturity of four selected Palaeozoic regions; the Forth Approaches Basin (Quadrant 26), the Mid North Sea High (Quadrant 36), an area to the south of the MNSH (Quadrants 41, 42, 43) and an area to the east of the MNSH (Quadrants 29 and 38; the North Dogger and Quadrant 29 basins). Few data were available for the latter area so this region was modelled using two ‘scenario’ wells to consider different possible burial histories and the generation potential. For the 1D well modelling, the main play examined was generation from the late Palaeozoic mid–late Carboniferous Scremerston/Firth Coal, Yoredale and Millstone Grit formations and laterally equivalent Cleveland Group. The main caprock formation was expected to be the Zechstein Group. Other Palaeozoic rocks were also examined as potential source rocks.