Basin and petroleum systems modelling to characterise multi-source hydrocarbon generation: A case study on the inner Moray Firth, UK North Sea.

In this paper we used basin and petroleum systems modelling (BPSM) of the Inner Moray Firth, UK North Sea to identify the contributions of different source rocks, mixing ratios of accumulated hydrocarbons, and migration pathways of charging the three known fields in the basin – Beatrice, Jacky and Lybster fields. In this study, model scenarios indicate that extensive faulting is a key control on hydrocarbon migration and accumulation, that the accumulations in the basin do not contain Kimmeridge Clay Formation oil, and that they are mixed in a ratio of ∼65:35 Devonian Fish Bed vs Pentland Formation contribution. Migration modelling suggests that Beatrice Field was charged predominantly by proximally sourced hydrocarbons, whereas Jacky and Lybster fields were charged by a near-even mix of proximal and deep-basin hydrocarbons from the Great Glen Sub-Basin. • Modelling shows that the basin is a co-sourced petroleum system. • Devonian Fish Beds and Pentland Formation generate the most hydrocarbons. • The KCF generates little hydrocarbons but is mature in the deeper basin regions. • Charging of the fields, is through both vertical and lateral migration. • Basin is a poor petroleum system due to extensive faulting and basin activity. [ABSTRACT FROM AUTHOR]