不同沉积环境地层中的芳烃分布特征

DISTRIBUTION CHARACTERISTICS OF AROMATICS IN FORMATIONS UNDER DIFFERENT SEDIMENTARY ENVIRONMENTS

为了研究不同沉积环境地层的芳烃分布，把原油和生油岩中的部分芳烃化合物分为与陆生植物有关的芳烃，与盐湖相地层有关的芳环稠合噻吩，与沉积相有关的芳构化甾烃三大类。浅海碳酸盐岩沉积物中，与树脂类物质、燃烧、煤有关的芳烃及三芳甾烃的强度很低。浅水碳酸盐－膏盐交互相沉积物中，与树脂类物质、燃烧、煤有关的芳烃强度有所增加，三芳甾烃强度仍然较低，很多样品中能见到４－甲基二苯并噻吩化合物。内陆湖相沉积物几乎与浅海碳酸盐相有相同的芳烃分布。湖盆边缘相地层中三芳甾烃，与树脂类物质，燃烧有关的芳烃强度都较高，但噻吩类化合物强度低。内陆盐湖相与湖相沉积物芳烃分布相似，只是４－甲基二苯并噻吩强度高。与火山喷发有关的沉积物中与湖盆边缘相有近似的芳烃分布，但与燃烧有关的芳烃强度更大。这些不同沉积环境地层的芳烃分布规律，可用于研究原油的油源。

Aromatic compounds are classified into three types:higher plant related aromatics saltand gypsum related fused thiophene compounds and sedimentary facies related aromaticsteroids. The shallow water marine carbonate sediments are distinguished by trace amountsof resin and combustion related aromatics and tri-aromatic steroids. In shauow water sedi-ments alternated by marine carbonates,gypsum and salts are increasing in resin,combustion,and coal related aromatics,tri-aromatic steroids remain to be low,4-methyldibenzothiophenecan be seen in some samples. The aromatics distribution of inland lake facies are the same asshallow water marine carbonate sediments. The lake border area facies is characterized byhigher content of tri-aromatic steroids,resin and combustion related aromatics,but thiophenecompounds are always low. The inland salt lake sedimentary facies is similar to the inlandlake facies,the difference between these two is only higher content of 4-methyldiben-zothiophene in the former.The aromatics distribution in the matter from volcanic eruption issimilar to the lake border facies,but with higher content of combustion related to aromatics.The regular features of aromatics distribution in the sediments with different sedimentary environments are useful in the research source of crude oil。