The main source rocks for the hydrocarbons at the Valdemar field (Danish North Sea) are the Upper Jurassic – lowermost Cretaceous organic‐rich marine shales of the Farsund Formation. However, geochemical analyses of retained petroleum in reservoir cores show variations in oil type and maturity which indicate a complex charging history. This paper reviews the organofacies and source rock quality variations in 55 samples of the Farsund Formation from the North Jens‐1 well (Valdemar field) within a sequence stratigraphic framework in order to discuss the source of the hydrocarbons. Petrographic and geochemical data, including biomarker analyses, were integrated in order to characterize the kerogen composition, original source rock potential and depositional environment of the Farsund Formation.

中文翻译：

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丹麦北海Valdemar油田上侏罗统-下最白垩统海相页岩烃源岩质量变化及其与油的关系

Valdemar油田（丹麦北海）的碳氢化合物的主要烃源岩是上侏罗统（Farsund组）的最低白垩纪有机富集海相页岩。但是，对油藏岩心中残留石油的地球化学分析表明，油的类型和成熟度存在差异，这表明了复杂的装油历史。本文讨论了层序地层框架内北延斯1井（Valdemar油田）的55个Farsund组样品的有机相和烃源岩质量变化，以讨论油气的来源。整合了岩石学和地球化学数据，包括生物标记分析，以表征Farsund组的干酪根成分，原始烃源岩潜力和沉积环境。