吐哈盆地中下侏罗统煤系地层源岩和油中饱和烃的GC/MS分析

Saturated hydracarbon of coal,carbonaceous mudstone and oils from the Lower Jurassic coal measures in the Turpan basin were studied,and biomarker characteristics and coal thermal maturity analyzed to draw the following conclusions. There are many similar biomarker characteristics between oil from middl-lower Jurassic of Turpan Basin and coal and carbonaceous mudstone in the same strata. They all contain specific r-lupane, I-norbietane, C24-tetracyclic and high content of C29-steranes. These characteristics suggest that they have similar matter source of the organic matter derived from matter with abundant high plants. Meanwhile, biomarkers often used to indicate depositional environments characterized by high Pr/Ph ratio, little or no gammacerane and high abundance dibenzofurans, such biomarker distributions are indicative of suboxic and freshwater environment. Although coal and carbonaceous mudstone remain in lower thermal maturity (Ro=0.47-0.53), but C29-ββ/(αα ββ) sterane ratio (0.294-0.489) and bezohopane are detected. Because these ferture are related to bacterial activity, bacterial degrdation of organic matter maybe take an important role in coal-derived oil.     

不同溶剂抽提冷杉脂溶性物质的GC/MS分析

为了研究不同溶剂超声波抽提的冷杉脂溶性物质中有机化学成分的异同，采用氯仿一元溶剂、V（氯仿）∶V（甲醇）=3∶1的混合二元溶剂以及V（氯仿）∶V（甲醇）∶V（丙酮）=4 ∶1∶1的混合三元溶剂，超声波抽提冷杉脂溶性物质的化学成分，气相色谱法分离，质谱法鉴定其结构。结果表明，3种不同溶剂所抽提的脂溶性物质在提取率、化学成分及含量等方面存在较大的差异。用氯仿一元溶剂超声波抽提的脂溶性物质的提取率最高，化学成分比较全面，是冷杉脂溶性物质抽提的理想溶剂。     

低熟烃源岩有机质在微生物作用下的地球化学特征

对采自柴达木盆地涩北1井的2块钙质泥岩样品的饱和烃、芳烃和非烃馏分进行了系统的分析.检测出微生物特征生标MPI和角鲨烷化合物,在非烃馏分中检测出不饱和脂肪酸、异构脂肪酸和反异构脂肪酸.样品所处的地温为30℃左右,古环境细菌发育.同时检测出的8,14-断藿烷和烷基酮系列是微生物对沉积有机质改造的产物.在微生物作用下,低熟源岩有机质发生大分子向小分子转化,强烈的去甲基过程,藿烷C31/32αβ22S/(22S+22R)值和甾烷C29ββ/(ββ+αα)值等参数出现异常.微生物对低熟源岩的生物降解作用,有利于烃源岩生成气态烃,且对其降解具有饱和烃>芳烃>非烃的特征.     

甘肃窑街中侏罗世油页岩单体烃碳同位素分析对比研究

n-Alkanes is widely used in the study of geologic body, which occupies 50%-80% of the saturated hydrocarbons commonly. The biogenetic implication of these compounds hold a very important value for the evaluation of all source rock, so it is used as biomarker to backward the biogenetic source of deposit organic matter. In order to find the difference of the isotopic composition of different organic compounds before and after complexion the oil shale in Yaojie, Gansu sample was performed by 5 molecular sieve adsorptipon to study the variation of the isotope compositions of n-alkanes, isoalkanes and cyclanes. On the basis of the previous work, the mini-sized Soxhlet extraction set with a hot reflux device was adopted to enhance the recovery of samples and diminish the loss of light components in the tested samples.     

饱和烃前处理实验方法及碳/氢同位素在地球化学中的应用

The carbon/hydrogen isotope values of single molecule of saturated hydrocarbons has great importance in the judgement of parent material types, evolution degree identification, source rock evaluation and oil-source correlation. Therefore, the sample pre-treatment technique should be given much inportance, particularly for the crude oil and source rocks samples riched in steroids, terpenoids compounds which have experienced the degradation process. A fast and economical methods were established aimed to accurately measuring the carbon/hydrogen isotope values of geological samples by repeated experiments.