This paper reviews the Middle Jurassic petroleum system in the Danish Central Graben with a focus on source rock quality, fluid compositions and distributions, and the maturation and generation history. The North Sea including the Danish Central Graben is a mature oil province where the primary source rock is composed of Upper Jurassic – lowermost Cretaceous marine shales. Most of the shale-sourced structures have been drilled and, to accommodate continued value creation, additional exploration opportunities are increasingly considered in E&P strategies. Triassic and Jurassic sandstone plays charged from coaly Middle Jurassic source rocks have proven to be economically viable in the North Sea. In the Danish-Norwegian Søgne Basin, coal-derived gas/condensate is produced from the Harald and Trym fields and oil from the Lulita field; the giant Culzean gas-condensate field is under development in the UK Central North Sea; and in the Norwegian South Viking Graben, coalderived gas and gas-condensate occur in several fields. The coaly source rock of the Middle Jurassic petroleum system in the greater North Sea is included in the Bryne/Lulu Formations (in Denmark), the Pentland Formation (in the UK), and the Sleipner and Hugin Formations in Norway. In the Danish Central Graben, the coal-bearing unit is composed of coals, coaly shales and carbonaceous shales, has a regional distribution and can be mapped seismically as the ‘Coal Marker’. The coaly source rocks are primarily gas-prone but the coals have an average Hydrogen Index value of c. 280 mg HC/g TOC and values above 300 mg HC/g TOC are not uncommon, which underpins the coals’ capacity to generate liquid hydrocarbons (condensate and oil). The coal-sourced liquids are differentiated from the common marinesourced oils by characteristic biomarker and isotope compositions, and in the Danish Central Graben are grouped into specific oil families composed of coal-sourced oil and mixed oils with a significant coaly contribution. Similarly, the coal-sourced gases are recognized by a normally heavier isotope signature and a relatively high dryness coefficient compared to oil-associated gas derived from marine shales. The coal-derived and mixed coaly gases are likewise assigned to well-defined gas families. Coal-derived liquids and gas discoveries and shows in Middle Jurassic strata suggest that the coaly Middle Jurassic petroleum system has

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丹麦北海的煤源岩和生成的石油的回顾：一个未充分探索的中侏罗纪石油系统？

本文回顾了丹麦中央地堑的中侏罗统石油系统，重点关注烃源岩质量、流体成分和分布以及成熟和生成历史。包括丹麦中央地堑在内的北海是一个成熟的油区，其主要烃源岩由上侏罗统——最下层的白垩纪海相页岩组成。大多数页岩源结构已经钻探，为了适应持续的价值创造，勘探与生产战略越来越多地考虑额外的勘探机会。由煤质中侏罗系烃源岩充填的三叠系和侏罗系砂岩带已被证明在北海具有经济可行性。在丹麦-挪威的 Søgne 盆地，Harald 和 Trym 油田生产煤成气/凝析油，Lulita 油田生产石油；巨大的 Culzean 凝析油田正在英国北海中部开发；在挪威南维京地堑，煤成气和凝析气出现在几个领域。大北海中侏罗统石油系统的煤质烃源岩包括在 Bryne/Lulu 组（丹麦）、Pentland 组（英国）以及挪威的 Sleipner 和 Hugin 组。在丹麦中央地堑，含煤单元由煤、煤质页岩和碳质页岩组成，具有区域性分布，可作为“煤标记”进行地震测绘。煤质烃源岩主要含气，但煤的平均氢指数值为 c。280 mg HC/g TOC 和高于 300 mg HC/g TOC 的值并不少见，这支撑了煤产生液态碳氢化合物（凝析油和石油）的能力。煤源液体通过特征性生物标志物和同位素组成与常见的海洋源油区分开来，在丹麦中央地堑中被分为特定的油族，由煤源油和煤质贡献显着的混合油组成。类似地，与源自海相页岩的石油伴生气相比，煤源气通常具有较重的同位素特征和相对较高的干燥系数。煤成气和混合煤气同样属于定义明确的气族。中侏罗统煤成液和气的发现和显示表明，中侏罗统煤质油气系统具有 煤源液体通过特征生物标志物和同位素组成与常见的海洋源油区分开来，并且在丹麦中央地堑被分为特定的油族，由煤源油和煤质贡献显着的混合油组成。类似地，与源自海相页岩的石油伴生气相比，煤源气通常具有较重的同位素特征和相对较高的干燥系数。煤成气和混合煤气同样属于定义明确的气族。中侏罗统煤成液和气的发现和显示表明，中侏罗统煤质油气系统具有 煤源液体通过特征生物标志物和同位素组成与常见的海洋源油区分开来，并且在丹麦中央地堑被分为特定的油族，由煤源油和煤质贡献显着的混合油组成。类似地，与源自海相页岩的石油伴生气相比，煤源气通常具有较重的同位素特征和相对较高的干燥系数。煤成气和混合煤气同样属于定义明确的气族。中侏罗统煤成液和气的发现和显示表明，中侏罗统煤质油气系统具有 而在丹麦中央地堑，则分为特定的油族，由煤质油和煤质贡献显着的混合油组成。类似地，与源自海相页岩的石油伴生气相比，煤源气通常具有较重的同位素特征和相对较高的干燥系数。煤成气和混合煤气同样属于定义明确的气族。中侏罗统煤成液和气的发现和显示表明，中侏罗统煤质油气系统具有 而在丹麦中央地堑，则分为特定的油族，由煤质油和煤质贡献显着的混合油组成。类似地，与源自海相页岩的石油伴生气相比，煤源气通常具有较重的同位素特征和相对较高的干燥系数。煤成气和混合煤气同样属于定义明确的气族。中侏罗统煤成液和气的发现和显示表明，中侏罗统煤质油气系统具有 煤成气和混合煤气同样属于定义明确的气族。中侏罗统煤成液和气的发现和显示表明，中侏罗统煤质油气系统具有 煤成气和混合煤气同样属于定义明确的气族。中侏罗统煤成液和气的发现和显示表明，中侏罗统煤质油气系统具有