氨基酸、脂肪酸对过渡带气、低熟原油形成的意义

Significance of Amino Acids and Fatty Acids for the Formation of the Bio-thermocatalytic Transition Zone Gases

对草海盆地泥炭、柴窝堡盆地第四系沉积物以及辽河东部凹陷、胜利东营凹陷、苏北金湖凹陷等第三系烃源岩中氨基酸、脂肪酸进行定性、定量分析，并开展热模拟实验。研究表明氨基酸主要赋存于沥青中，分解后可以生成烃类气体和Ｎ２气，对过渡带气的形成可作出贡献。烃源岩干酪根和沥青中的脂肪酸含量不少，沥青中脂肪酸以一元酸为主，具偶碳优势，干酪根中脂肪酸以二元酸为主，不具偶碳优势。沥青和干酪根中脂肪酸脱羧基后产生烷烃，对过渡带气和低熟油都可作出贡献，沥青中脂肪酸是生成低熟油中具奇碳优势正烷烃的主要物源。

The amino acids and fatty acids in sediments of Caohai, Chaiwopu, Liaohe, Jiyang and Subei Basins were quantitatively analysed in this study. Based on the results, the gas-generating tests of peat and mudstone were carried out to investigate distribution and compostition of fatty acids in the extract and kerogen. As a result, some points are drawn as follows:1. Amino acids in sediments are mainly present in the soluble organic matter and may produce hydrocarbons during early diagenesis stage,contributing to the formation of Bio - thermocatalytic Transition Zone Gases.2.α-fatty acids in sediments are mainly present in asphaltene and may produce hydrocarbon, contributing to the formation of immature oil during early diagenesis stage.3. Kerogen is rich in α,ω - fatty acids which are favourable to the generation of Bio-thermocatalytic Transition Gases during early diagenesis stage, and produce hydrocarbon in mature oil druing oil generating stage.