不同类型有机黏土中化学结合态有机质生油能力差异性研究

通过高温高压加水热模拟,对蒙脱石型有机黏土中化学结合态有机质与伊利石型有机黏土中化学结合态有机质的生油能力进行了比较研究。实验结果表明,2种类型有机黏土中化学结合态有机质向原油的极限转化能力相当,生成原油数量的多少主要取决于有机质的多寡;有机黏土中化学结合态有机质会对低熟油做出贡献,但它们主体的贡献都在于生成成熟原油;蒙脱石型有机黏土中化学结合态有机质较伊利石型有机黏土中化学结合态有机质表现出更好的持续生烃性;2种类型的有机黏土,其化学结合态有机质都易生成含氮、氧、硫等杂原子的非烃物质;蒙脱石型有机黏土中化学结合态有机质较伊利石型有机黏土中化学结合态有机质更易生成含氮、氧、硫等杂原子的非烃物质。因此,对于早期生过烃的深层泥质烃源岩,在二次生烃评价时,应重点强调有机碳含量、弱化矿物类型,同时应考虑原油品质变差这一现实。

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.