Abstract In this study, bituminous shale samples were collected from Late Jurassic sedimentary section in the Marib oilfields to study their petrologic and organic geochemical properties. The results of this study indicate that the Late Jurassic bituminous shales can be considered as an oil-source rocks in the Sabatayn Basin (NW Yemen). The analyzed Late Jurassic shales have high organic matter (TOC up to 10%) content of kerogen Types I/II. These kerogen types in the analyzed samples are consistent with the high dominance of alginite and amorphous organic matter. Open pyrolysis–gas chromatography results are generally consistent with the Rock-Eval results and further indicate that the analyzed shale samples contain Types I/II and II-S kerogen and generally can produce paraffinic oils with low to high wax content. Type II-S kerogen can produce oil with high sulphur content at low maturity level. The maturity data reflect immature and very early maturity stages of petroleum formation of the Late Jurassic bituminous shales. Therefore, the kerogen types in the Late Jurassic bituminous shales has not been altered by thermal maturity for oil generation, thus, artificial heating is required of kerogen cracking generate significant oil.

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来自 Sabatayn 盆地（也门西北部）Marib 油田的晚侏罗世沥青页岩：地球化学和岩石学分析揭示油页岩资源

摘要 本研究从马里布油田晚侏罗世沉积剖面采集沥青页岩样品，研究其岩石学和有机地球化学性质。本研究结果表明，晚侏罗世沥青页岩可被视为萨巴泰盆地（也门西北部）的油源岩。分析的晚侏罗世页岩具有高有机质（TOC 高达 10%）的干酪根 I/II 型含量。分析样品中的这些干酪根类型与藻酸盐和无定形有机物的高度优势相一致。开放式热解-气相色谱结果与 Rock-Eval 结果基本一致，进一步表明分析的页岩样品含有 I/II 型和 II-S 型干酪根，通常可以生产含蜡量从低到高的石蜡油。II-S 型干酪根可以在低成熟度水平下生产高硫含量的油。成熟度数据反映了晚侏罗世沥青页岩油气形成的未成熟和极早成熟阶段。因此，晚侏罗世沥青页岩的干酪根类型并未因生油热成熟而改变，因此干酪根裂解产油需要人工加热。