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通过生物气模拟实验、生物气生成条件及储盖条件分析，建立起柴达木盆地一里坪地区上新统狮子沟组（Ｎ２３）生物气成藏模式。首先，根据厌氧微生物菌群的检测与计数和模拟生化产气实验，证实一里坪 Ｎ２３天然气为生物气。其次，根据生物气形成机理的特殊性，从沉积相、古气候条件及温度条件分析生物气形成条件，认为一里坪地区 Ｎ２３沉积湖盆总体水体多为微咸至咸水环境，草本植物丰富，奠定了生物气形成的物质基础，高盐度和低温条件减缓了沉积有机质向生物气的转化进程，使生物气的下限深度增加。然后，对储盖层条件进行分析，认为一里坪地区 Ｎ２３生物气储层和盖层条件不错，盖层封盖机理有物性差异封闭和烃类浓度封闭两种。最后，建立了一里坪地区Ｎ２３生物气动态成藏模式，整个成藏过程可分为游离散失、水溶气藏、纯气藏－水溶气藏和水溶气藏－纯气藏四个阶段。
Based on the biogas simulation experiment, biogas generation conditions and the conditions of reservoir and cover, the biogas accumulation pattern of the Upper Triassic Shizigou Formation (N23) in the Yiliping area, Qaidam basin was established. First of all, according to the detection and counting of anaerobic microbial flora and biogas production simulation experiments, it was confirmed that one mile of N23 natural gas is biogas. Secondly, according to the particularity of biogas formation mechanism, the formation conditions of biogas from sedimentary facies, paleoclimatic conditions and temperature conditions suggest that the overall water body of N23 lacustrine basin in Yiliping district is mostly in the salty to brackish water environment with rich herbaceous plants , Which laid the material basis for the formation of biogas. The high salinity and low temperature conditions slowed down the conversion of sedimentary organic matter to biogas and increased the lower limit of biogas. Then, the conditions of reservoir caprock are analyzed. It is concluded that the N23 biogas reservoirs and caprocks in Yiliping area are in good conditions, and the mechanism of cap capping is closed with different physical properties and closed with hydrocarbon concentration. Finally, the dynamic model of N23 biogas accumulation in the Yiliping area was established. The whole process of accumulation can be divided into four stages: free dissipation, water-soluble gas reservoir, pure gas reservoir - water-soluble reservoir and water-soluble gas reservoir - pure gas reservoir.