牛38井烃源岩排烃门限的确定

对牛38井主力烃源岩段沙河街组三段进行了密集测试分析，以排烃潜力指数为研究参数，对牛38井沙三亚段排烃潜力指数剖面分布进行了分析。研究结果表明，牛38井沙三段开始形成规模排烃的临界饱和量为300 mg/g，排烃的临界饱和度为8.56%（考虑误差，其值在2.5%~9.5%之间），在达到排烃高峰时，Ⅰ型、Ⅱ₁型、Ⅱ₂型及Ⅲ型有机质的HEA值分别为800 mg/g、600 mg/g、380 mg/g、160 mg/g，对应的HES值分别为64.42%、29.86%、13.1%、1.59%，Ⅲ型有机质不能达到排烃门限条件，基本为无效有机质。

DETERMINING THE EXPELLING HYDROCARBON THRESHOLD OF SOURCE ROCK OF WELL NIU 38

The member 3 of Shahejie Formation, main source rock section of Well Niu 38 is closely surveyed and analyzed to investigate the expelling hydrocarbon threshold of the source rock. Taking Sp/TOC as parameter, the Sp/TOC value profile distribution of Sha 3 sub member of Well Niu 38 is analyzed. The result shows: the critical saturation quantity of grand expelling hydrocarbon of Sha 3 member of Well Niu 38 is 300 mg/g and the critical saturation of expelling hydrocarbon is 8.5% (considering error, it is 2.5%-9.5%); when reaching the peak of expelling hydrocarbon, the HEA values of organic matter of typeⅠ, typeⅡ1, typeⅡ2 and type Ⅲ respectively are 800 mg/g, 600 mg/g, 380 mg/g and 160mg/g and the corresponding HEA values respectively are 64.42%, 29.86%, 13.1% and 1.59%; the organic matter of type Ⅲ fails to reach the expelling hydrocarbon threshold, almost being invalid one. (Financed by the project of the Key Technologies Research and Development Program of the Tenth “Five Year Plan, No. 2001BA605A-09)