Light and condensable oils derived from mature kerogen and residual oil in deep source rocks have contributed strongly to a rapid increase in oil production. In this study, oil expulsion from kerogen and shale was simulated by selective solvent extraction (hexane/toluene, 9:1 v/v, instead of the commonly used dichloromethane) and by returning the extracts (so-called “oil a”) back into a controlled mass of mature kerogen. The maturity intervals and potential of the light oil and condensates were investigated by analyzing the yields of different hydrocarbons from the subsequent pyrolysis of mature kerogen-“oil a” mixtures. The gas-to-oil ratio was used to constrain the maturity range for the light oil, condensate, and gas stages. The lowest equivalent vitrinite reflectance (EVR_o, 1.9–2.1%) for the gas stage was compatible with commonly accepted models. The EVR_o cutoff of 1.55–1.75% between light oil and condensate was higher than that in traditional models, although this depended primarily on the generality of the “condensate” definition. An EVR_o ranging between 1.35 and 1.55–1.75% was defined in this work as the “light oil/gas” substage within the commonly accepted condensate/wet gas stage. Moreover, yields of hydrocarbons from the cracking of “oil a” were distinctly affected by mature kerogen. This effect showed little difference on the yield of C_6–14 hydrocarbons and C₁₅₊ hydrocarbons but notable difference for the gases between types I and II kerogens. The release of C_6–14 hydrocarbons was promoted when the release of C₁₅₊ hydrocarbons was notably inhibited. Approximately linear relationships were established between maximum yields of liquid hydrocarbons and the carbon content of “oil a” (selective solvent extraction products) in the mixtures. This relationship was helpful in estimating both oil and total petroleum potential of deep source rocks that have undergone oil generation and expulsion, but it was dependent on the composition of the solvents used in extraction.

中文翻译：

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I / II型干酪根的热分解和驱出后可揭示深部烃源岩中的轻质油和凝析油的潜力

源自成熟干酪根的轻质和可凝性油以及深层烃源岩中的残余油对石油产量的快速增长做出了重要贡献。在这项研究中，通过选择性溶剂萃取（己烷/甲苯，9：1 v / v，而不是常用的二氯甲烷）和从萃取物返回到所谓的“油a”中，模拟了从干酪根和页岩中驱油的过程。进入受控质量的成熟干酪根。通过分析成熟干酪根-“ a油”混合物的后续热解过程中不同烃类的收率，研究了轻质油和凝析油的成熟间隔和潜力。气油比用来限制轻油，凝析油和气段的成熟度范围。最低等效​​镜质体反射率（EVR _o（1.9–2.1％）的气体阶段与公认的模型兼容。所述EVR _Ô的截止轻油和冷凝之间1.55-1.75％显着高于传统的模型更高，尽管这主要依赖于“冷凝物”的定义的一般性。在这项工作中，将EVR _o定义为1.35到1.55-1.75％之间是普遍接受的冷凝水/湿气阶段中的“轻油/天然气”子阶段。而且，成熟的干酪根明显地影响了“油a”裂解产生的碳氢化合物的产量。这种作用显示出对C _6-14烃和C ₁₅₊烃的收率几乎没有影响，但I型和II型干酪根之间的气体有显着差异。C _6-14的发布当显着抑制C ₁₅₊烃的释放时，促进了烃的生长。在液态烃的最大产率与混合物中“油a”（选择性溶剂萃取产物）的碳含量之间建立了近似线性关系。这种关系有助于估算经历生油和排空作用的深层烃源岩的石油潜力和总石油潜力，但它取决于提取中所用溶剂的组成。