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中国低熟煤成气的发现及研究始于渤海湾盆地辽河坳陷、苏北盆地等区块,但其后低熟气勘探主要在吐哈盆地中生代获得突破,因此早期煤成低熟气地球化学研究主要集中于吐哈盆地。近年来在渤海湾盆地辽河坳陷及黄骅坳陷低熟煤成气勘探初见成效,为系统、深入研究低熟煤成气地球化学特征提供了机遇。以渤海湾盆地黄骅坳陷和辽河坳陷古近系低熟煤成气为研究对象,结合吐哈盆地中生代低熟煤成气地球化学特征,对中国低熟煤成气地球化学特征进行了完善,同时对渤海湾盆地低熟气勘探潜力进行了探讨。结果表明:渤海湾盆地黄骅坳陷和辽河坳陷古近系天然气δ~(13)C_1<-39‰、δD_1<-200‰、δ~(13)C_2-δ~(13)C_1>10‰、烃源岩RO值介于0.5%~0.9%之间,具有与吐哈盆地类似的低熟煤成气特征。在渤海湾盆地除了黄骅坳陷和辽河坳陷外,其他坳陷沙河街组也具有低熟气勘探潜力;渤中凹陷、歧北次凹、东营民丰凹陷东营组亦有低熟气勘探潜力。
The discovery and study of low-mature coal gas in China began in the Liaohe depression and the Subei basin in the Bohai Bay basin. However, subsequent exploration of low-mature gas mainly made breakthroughs in the Mesozoic in the Turpan-Hami basin. Therefore, Chemical research is mainly concentrated in Turpan-Hami basin. In recent years, the achievements of low-mature coal gas exploration in the Liaohe Depression and the Huanghua Depression in the Bohai Bay Basin have achieved initial success, which provides an opportunity for systematic and in-depth study of the geochemical characteristics of low-mature coal gas. Taking the low-mature coal gas of Paleogene in the Huanghua Depression and the Liaohe Depression of the Bohai Bay Basin as the research object, the geochemical characteristics of the low-mature coal gas in China were improved according to the geochemical characteristics of the Mesozoic low-mature coal gas in Turpan-Hami basin , And explored the potential of low-grade gas exploration in the Bohai Bay Basin. The results show that the δ13C_1 <-39% o, δD_1 <-200% o, δ13C_2-δ13C_1> 10% of the natural gas in the Huanghua Depression and the Liaohe Depression of the Bohai Bay Basin , And the RO value of source rocks ranges from 0.5% to 0.9%, which is similar to that of Turpan-Hami basin. In addition to the Huanghua Depression and the Liaohe Depression in the Bohai Bay Basin, Shahejie Formation of other sags also have low-potential gas exploration potentials; the Bozhong Depression, the Qibei Sag, and the Dongying Formation in the Minfeng Depression of Dongying also have low-potential gas exploration potentials .