西峰油田延长组烃源岩生烃潜力评价

Geochemical characteristics and hydrocarbon generation potential of the source rocks in Yanchang Formation, Xifeng Oilfield, Ordos Basin, NW China

通过RockEval岩石评价、显微镜下观察、有机元素分析、镜质体反射率等分析,对鄂尔多斯盆地西峰油田延长组烃源岩进行了地球化学特征研究及生烃潜力评价。分析结果表明:①延长组长7段、长8段烃源岩有机质丰度普遍较高,其中,中等和好烃源岩所占比例分别为94%和77%,长8段烃源岩样品有机质丰度与生烃潜力均高于长7段烃源岩样品,董志区烃源岩样品高于白马区烃源岩样品;②长7段、长8段烃源岩有机质类型多为腐殖腐泥型;③长7段、长8段烃源岩有机质热演化普遍处于成熟阶段,具有生成大量原油的有利条件,这对该区油气源对比和油气勘探具有重要的价值。

The results of Rock-Eval, microscope observation, organic elements and vitrinite reflectance analysis of 45 source rock samples from Yanchang Formation, Xifeng Oilfield, Ordos Basin, used for researching the geochemical characteristics and assessing the hydrocarbon potential, suggest that the source rocks in Member 7 and 8 of the Yanchang Formation are relatively rich in organic matter and the medium and good ones account for 94% and 77%,respectively; most of the organic matter in the two members was humic-sapropel; and the source rock thermal evolution developed at a mature stage with favorable conditions for oil generating.