Organic geochemistry in exploration of the Northern North Sea

Geochemical characterisation and genetic origin of oils and condensates in the South Viking Graben, Norway

“…Although several source-prone horizons have been identified in the area (Field, 1985;Thomas et al, 1985), it is generally agreed that the Oxfordian to Ryazanian Draupne Formation is the principal hydrocarbon source rock (Barnard and Cooper, 1981;Cornford, 1998;. Oil and gas is also generated by the underlying Upper Jurassic Heather Formation of Callovian to Oxfordian age.…”

Geothermal history and petroleum generation in the Norwegian South Viking Graben revealed by pseudo-3D basin modelling

“…The data, however, appear to confirm the conclusion of Isaksen et al (2002) that the Middle Jurassic source rocks are mainly gas-prone with only minor oil potential. Field (1985) indicates coal thicknesses of more than 30 m in the axial parts of the graben, whereas well log analysis of the 38 modelled 1D sites showed a maximum thickness of up to 56 m in Well 25/7-2.…”

“…The Hugin and Sleipner Formation of event 5 and the Draupne and Heather Formation including events 6, 7 and 8 constitute the main source rocks in the area (Field, 1985;Isaksen and Ledje, 2001;Isaksen et al, 2002;.…”

“…Upper and Middle Jurassic as well as Triassic sandstones have also been found to be hydrocarbon bearing. Principal source rocks are the Upper Jurassic Heather and Draupne Formations (Field, 1985;Isaksen and Ledje, 2001; and to a lesser extent the Middle Jurassic Hugin and Sleipner Formation (Isaksen et al, 2002;Justwan et al, 2006). After nearly 40 years of exploration and drilling of 270 exploration wells as well as 279 development wells in the Norwegian sector of the South Viking Graben, the size and frequency of discoveries appears to decline.…”

“…The main source rock units in the area, the shales and sands of the Heather (event 6) and the shales of the Draupne Formation, have been deposited during subsequent sea-level rise (e.g., Field, 1985;Isaksen and Ledje, 2001;. The Draupne Formation can be subdivided into a lower, syn-rift section of Oxfordian to Middle Volgian age (event 7) and a post-rift section of Middle Volgian to late Ryazanian age (event 8) (Rattey and Hayward, 1993).…”