Abstract

The Permo–Triassic succession of the Cheshire Basin exhibits complex geological controls on its hydrocarbon prospectivity. This study integrates 3D reservoir modeling in Petrel with thermal maturity and burial history analysis to assess reservoir quality, source rock potential, and trap effectiveness. Facies analysis reveals strong spatial variability, with aeolian-dominated deposits in the north, alternating aeolian–fluvial facies in the south, stable fluvial systems in the east, and channel-fill deposits in the west. Thermal maturity evaluation of the Westphalian Coal Measures Formation indicates moderate source rock potential. Burial history modeling identifies two main burial phases but suggests that maximum temperatures were insufficient for significant oil generation; however, localized wet gas generation is possible. Despite the presence of favorable source and reservoir units, the lack of commercial discoveries is attributed to ineffective sealing. Major fault systems dissect both reservoir and seal units and extend to the surface, enabling vertical hydrocarbon leakage. Hydrocarbons may have been sourced from the Holywell Shale in the adjacent East Irish Sea Basin. Structural leakage is therefore considered the primary limitation to effective hydrocarbon entrapment in the Cheshire Basin.