抄録
The purpose of this paper is to discuss the possibility of catalytic actions of acid silicates in the process of formation of petroleum in the Japan Sea side of Japan. Mineral compositions of clay fractions of 76 specimens collected from source rocks of petroleum in this region are analysed by means of the X-ray spectrometer. As to the composition of organic matter in these specimens, contents of the total organic carbon, and amounts and liquid chromatographic compositions of the arganic matter extracted by the mixture of benzene, alcohol and aceton (50: 25: 25) are determined.
There is found no definit relation between the catalytic activity estimated from the clay mineral composition and the composition of organic matter, especially the ratio of light fractions (paraffin, cycloparaffin and aromatics) to the total organic matter extracted.
It may be concluded that the clay minerals were placed in inactive conditions during the period of formation of petroleum in this region. The genesis of petroleum and the variability of its com position are assumed to be largely due to the direction and degree of decomposition of the original organic matter in the period of its deposition.
