Objection is lodged against the method used for calculating hydrocarbon production proposed in comrade Li's paper"A preliminary study of hydrocarbon production from various types of kerogen at different mature stage"(refer to"Oil Gas Geology"

Vol.2

No.3.).In this paper

a brief discussion is given on hydrocarbon productivity

its quantity from source rocks

its limit of cumulative hydrocarbon potential

as well as calculating method and related data etc.It is pointed out that not only Li's calculating method and result obtained are questionable

but also his basic data used for calculation are unreliable.The hydrocarbon productivity suggested in the paper is only the ratio of average hydrocarbon obtianed from kerogen elemental components.The author has suggested that calculating hydrocarbon must be based on its threshold.In addition

some concept has accordingly proposed for solving this important object in this study.