Oil generation abilities of chemically bound organic matter in different types of organic clay complexes

A series of high temperature and high pressure thermal simulation experiments were carried out to compare the oil generation ability of chemically bound organic matter in montmorillonite organic clay and illite organic clay. Both types of c chemically bound organic matter had the same ability to translate into crude oil, and it was the amount of organic matter that controlled the amount of crude oil. Chemically bound organic matter in organic clay would contribute to immature oil; however, most organic matter contributed to mature crude oil. The chemically bound organic matter in montmorillonite organic clay had a greater ability to sustain oil generation than that in illite organic clay. Both types of chemically bound organic matter easily generated non-hydrocarbons which contained heteroatoms such as nitrogen, oxygen and sulfur. The chemically bound organic matter in montmoril-lonite organic clay generated non-hydrocarbon more easily. Therefore, the importance of organic matter quantity rather than mineral types should be emphasized when secondary hydrocarbon generation ability of argillaceous source rock is assessed. At the same time, it appears that crude oil quality would become poor.