前言一般认为,石油、天然气是沉积岩中的有机物(主要是干酪根)通过热或微生物的分解作用而生成的(有机成因说)。有机成因说在地质学上是以石油、天然气大部分(至少是已形成矿藏的部分)都产于所谓的沉积盆地为根据的。另外,通过烃类碳同位素、CPI和生物标志物的测定以及干酪根的热分解实验等,从有机地球化学角度验证这一学说的研究也在进行中。近年的文章中,一方面指出了有机成因说中存在的问题(氢的供给不足等),同时还报道了很可能是无机成因的烃类的发现。对于东太平洋海隆和格拉帕戈斯裂谷热水带出的甲烷、东非裂谷带吉布湖水中溶存的过饱和甲 Preface It is generally accepted that petroleum and natural gas are generated by the decomposition of organic matter (mainly kerogen) in sedimentary rocks by heat or by microorganisms (organic genesis). The organic cause is said to be geologically based on the so-called sedimentary basins in which most of the oil and gas (at least those that form the mineral deposit) are produced. In addition, studies on the validation of this theory from the perspective of organic geochemistry have also been carried out through the determination of hydrocarbon carbon isotopes, determination of CPI and biomarkers, and thermal decomposition of kerogen. In recent years, the article pointed out the problems of organic genesis (shortage of hydrogen supply, etc.) on the one hand, and also discovered the discovery of hydrocarbons that are likely to be inorganic causes. For the methane from the hot waters of the Rift Valley and the Galapagos Rift in the East Pacific Rift,