基于有机元素的干酪根类型指数计算

Study of kerogen type index through the calculation of organic elements

干酪根有机元素的范氏图法是被广泛采用的划分干酪根类型的方法,在实践中发现范氏图与干酪根类型指数TI法划分的结果有较大出入.利用海拉尔盆地乌尔逊凹陷143个样品实测的干酪根类型指数TI和有机元素数据,进行非线性回归,提出一种较为简洁的利用有机元素H/C、O/C直接计算TI的公式,将计算结果称作ETI;利用松辽盆地北部和海拉尔盆地贝尔凹陷51个样品对ETI进行验证.结果表明,ETI确定干酪根类型与TI法的一致性明显优于范氏图法与TI法的一致性.ETI的提出为利用干酪根有机元素测试结果评估干酪根类型提供新的研究思路和方法.

Van Krevelen diagram of kerogen organic element is applied to classify the kerogen types.In practice we find that the result of Van Krevelen diagram doesn’t correlate correctly with that of kerogen type index(TI).This paper proposes one simpler formula for calculating TI by organic element H/C,O/C,according to nonlinear regression with kerogen type index(TI)and organic element data of 143samples from Wuerxun depression of Hailar basin.The calculating result is named as ETI.51samples of north Songliao basin and Beier depression were applied to prove the formula.The results show that ETI which confirm kerogen types consistent with TI excelled coherence with Van plot and TI.The proposing of ETI provides new ideas and methods for using kerogen organic element test results to evaluate kerogen types.