不同沉积环境烃源岩芳烃馏分单体烃碳同位素分布特征及其意义  

Carbon Isotope Distribution Characteristics and Significance of Monomer Aromatic Fraction in Source Rocks from Different Sedimentary Environments

作　　者：张敏 陈祖林[1] 程熊[1] 姜连 赵勇[2] 

机构地区：[1]长江大学地球环境与水资源学院油气资源与勘探技术教育部重点实验室(长江大学),湖北武汉430100 [2]中石化石油工程技术研究院,北京100101

出　　处：《石油天然气学报》2013年第12期13-17,4,共5页Journal of Oil and Gas Technology

基　　金：高等学校博士学科点专项科研基金项目(20104220110001);国家自然科学基金项目(40973041)

摘　　要：通过对来自塔里木盆地海相(9个)、吐哈盆地沼泽相及湖相(6个)和柴达木盆地湖相(9个)共24个烃源岩样品芳烃分离、纯化后,应用色谱-同位素比值质谱(GC-IR-MS)分析技术,系统剖析了不同沉积环境中芳烃馏分单体烃碳同位素组成特征。研究结果表明,对于不同沉积环境的烃源岩芳烃馏分单体烃碳同位素组成呈现出δ13 C湖相>δ13 C沼泽相>δ13 C海相的规律,由此证明母质来源和沉积环境是影响其分布的主控因素之一。不同沉积环境1,6-DMN、1,2,5-TMN、1-MP、9-MP和1,9-DMP化合物的碳同位素组成具明显差异。芳烃同分异构体之间的同位素组成差异主要由沉岩过程中的动力学分馏效应所致,而热演化过程对芳烃单体烃碳同位素组成影响不大。Twenty four source rocks from Tarim Basin marine(nine),Turpan-Hami Basin swamp and lacustrine(six) and Qaidam Basin lacustrine environments(nine)were selected for a systematical analysis of stable carbon isotope for monomer aromatic hydrocarbons by GC-IR-MS after aromatic hydrocarbon separation and purification.The analysis results indicate that different monomer aromatic hydrocarbon isotopic compositions in source rocks from different sedimentary environments present a trend of depletion inδ13 C in the extracts of marine,swamp and lacustrine source rocks, orderly.The carbon isotope composition of 1,6-DMN,1,2,5-TMN and 1,9-DMP from source rocks has significant differences in different sedimentary environments.Isotopic composition diversities between aromatic isomers are mainly caused by the dynamic fractionation effects during diagenesis,while the impact of thermal evolution is less on the monomer aromatic hydrocarbon isotopic compositions.

关 键 词：芳烃单体烃 碳同位素 动力学分馏效应 烃源岩 沉积环境 

分 类 号：P618.13[天文地球—矿床学]