有机岩石学研究有机质类型和成熟度的改进

IMPROVEMENT ON STUDY OF ORGANIC TYPES AND MATURATION WITH ORGANIC PETROLOGY

作者对我国两个盆地的43个干酪根和煤包体样品进行了有机岩石学研究。用透射光、反射光和荧光相结合的方法进行了显微组份定量,测定了荧光光谱和镜质体反射率,并建立了荧光参数与镜质体反射率的关系图版。结果表明,通常所用的类型指数划分干酪根类型的方法存在很大的缺陷。无定形为主的干酪根可以属于任何一种化学类型,它的富氢程度取决于其来源及沉积和早期成岩环境,荧光方法可以有效地区分富氢和贫氢无定形,建立干酪根的光学分类与元素分析的关系;另外一些干酪根样品的镜质体反射率异常低(系吸附效应的结果),不能反映有机质成熟度,荧光参数可以弥补R°的不足,建立荧光参数与R°的关系图版,用荧光参数推测镜质体反射率值。

Forty-three samples of kerogen and inclusions in coals from two basins in China were studied for organic petrology.By combined use of transmissible, reflective lights and fluorescence, the quantification of macerals, the determination of fluorescence spectra and vitrinite reflectance,plates for the relations between fluorescence parameters and vitrinite reflectances were accomplished. The results show that there are some defects in the methods of determing kerogen types by current indexes. Amorphous-dominated kerogen may belong to any chemical type, while its hydrogen enrichment depends on the source of organics, the sedimentary environments and early diagenesis. The fluorescence method can be used to distinguish amorphous kerogen enriched hydrogen from that of poor hydrogen effectively, and to establish the relation between optical classification and element analysis for kerogen) besides, some kerogen samples have very low values of vitrinite reflectance, being unable to reflect organic maturity. But fluorescence parameters can make some remedies about this defects of R°and develop relational plates between fluorescence parameters and R°, and infer the values of vitrinite relectance.