Prospectivity of structures in the Kvitebjørn: Huldragraben stepover, NorthernNorth Sea
MetadataShow full item record
Hydrocarbon exploration in mature provinces is now focusing on smaller play fairways previously viewed as overly structurally complex and with high associated risk. However, current economic circumstances combined with existing infrastructure are making these areas prospectively viable.This study present a case of complex Middle Jurassic fault blocks and horst structures generated in an extensional graben step-over setting in the northern North Sea. The play-fairway is developed with producing fields and several discoveries, proving charge, migration and top seal. The search is therefore focused on presence of reservoir rock and trapping mechanisms. The study area is located in the Kvitebjørn-Huldra transfer zone, part of the western margin of theViking Graben. It is considered a structurally complex region comprising down-stepping terracesand rotated fault blocks generated during phases of extension during Late Permian-Early Triassicand Middle-Early Cretaceous stage. The associated basin bounding normal fault zone exert the primary control on sedimentary basin geometry. Sedimentary systems within an active extensional system are controlled by a dynamic set of interaction and range of complex variables. An integrated study of seismic interpretation, fault analysis a thorough understanding of the depositional environment, sand distribution and complexstructural elements in the Kvitebjørn-Huldra transfer zone is developed. Attempts have been made in order to understand the structural geological system for the purpose of hydrocarbon exploration, allowing higher confidence in the assessment of reservoir presence and trap integrity. Newly reprocessed seismic data allow recognition of reservoir sands and prediction of potential reservoir quality and existence of an extensional top seal. Trapping mechanism typically rely on fault-related features, which is fundamentally controlled by extensional or compactional tectonic settings. Direct mapping of seismically defined stratigraphical sequences and their juxta position allow for an assessment of structural traps. Through this work three prospects and leads have been identified and assessed.