Abstract
The present author has reported that non-clastic siliceous and carbonate rocks have a tendency to generate “immature oils” at shallow depth, while clay-rich rocks generate oils at relatively deeper burial depth, and with this results as background, has proposed a petroleum generation model (e.g. TAGUCHI, 1986, 1989, 1990, 1991) revised conventional “kerogen origin theory of petroleum”, which is based on the concept that kerogen is a random condensation product of various biomonomers which were formed during diagenesis by hydrolysis of biopolymers and only fossil kerogen can form economic oil pools under thermal stress at the catagenetic stage.
In the meantime, recently, a new alternative mechanism for formation of kerogen based on the concept of selected preservation of resistant biopolymers has been proposed by several researchers (e.g. TEGELAAR et al., 1989 and others).
In this paper, the relationships between the new concept of kerogen formation and the modified model of conventional petroleum generation theory proposed by the present author are examined from a standpoint of oil formation.
