鄂尔多斯盆地东南部山西组泥页岩生烃热模拟实验

鄂尔多斯盆地东南部页岩气资源潜力巨大，目前缺乏对山西组泥页岩生烃潜力的系统评价，因而制约了对该区烃源岩资源潜力的客观评价。通过高压釜-封闭式金管的生烃热模拟实验，分析烃源岩生烃过程，对比山1段和山2段的生烃潜力，生烃动力学拟合证明实验结果真实可靠。实验结果表明：①甲烷和非烃类气体具有相似产出特征，重烃气C_2-5和液态烃具有相似产出特征；②当R_O值为0.80%~1.08%时，液态烃达到产率峰值；当R_O值达到1.47%~1.81%时，重烃气C_2-5达到产率峰值；当R_O值超过3%，重烃气C_2-5几乎全部裂解，干燥系数接近1；③实验表明山2段属于更好的烃源岩，结合页岩气井地化数据，进一步确认山2段生烃潜力远远超过山1段，研究认为山2段更适合作为鄂尔多斯盆地海陆过渡相页岩气的有利勘探层段。

Hydrocarbon generation simulation of source rocks in Shanxi Formation of Ordos Basin

Shale gas resources have a great potential in the southeast of Ordos Basin，the lack of the hydrocarbon generation potential evaluation of Shanxi Formation restricts the objective evaluation about resource rocks potential in this zone.Hydrocarbon products and hydrocarbon generation potential of Shanxi Formation were analyzed by pyrolysis experiments.The following results were obtained，(1)methane and non-hydrocarbon gases show similar yields characteristics，heavy hydrocarbon gasC_2-5 and liquid hydrocarbons show similar yields characteristics;(2)liquid hydrocarbon reaches the peak yield asR_O between 0.80%-1.08%,heavy hydrocarbon gas reaches peak yield asR_O between 1.47%-1.81%.WhenR_O exceeds 3%，heavy hydrocarbon gas is almost completely cracked，the drying coefficient is close to 1;(3)pyrolysis experiments show that the second member reservoir is a better source rock.Geochemical data of shale gas wells further confirmed that the hydrocarbon generation potential of second member reservoir is much larger than that of first member reservoir.It is concluded that the second member reservoir is a favorable exploration stratum of continental shale gas in Ordos Basin.