松辽盆地齐家古龙地区烃源岩有机岩石学研究

Organic petrology of the source rocks in Qijia-Gulong region, Songliao basin

采用有机岩石学全岩分析技术 ,系统研究了松辽盆地齐家古龙地区白垩系嫩江组烃源岩的显微组分组成、生烃组分及有机质热演化。该区烃源岩形态显微组分含量占全岩体积的 4.1%。嫩二段—嫩五段烃源岩显微组分以高等植物陆源输入占绝对优势 ,贫惰性组、富含镜质组、相对发育壳质组 ;嫩一段烃源岩腐泥组分含量较高 ,具有混合生源的特点 ,为该区主力烃源岩。藻类体是该区低熟油的重要生烃组分。利用镜质组反射率、孢子体荧光参数 ,将有机质热演化阶段划分为未成熟、低成熟两个阶段 ,二者界线所对应的镜质组反射率为 0 .5 % ,孢子体相对荧光强度为 2 .2 ,埋深为 10 5 0m。图 4表1参 4(马安来摘 )

Using whole rock analysis of organic petrology, a detail study on the maceral composition, hydrocarbon generating maceral and thermal evolution of the source rock of Cretaceous Nenjiang Formation in Qijia Gulong region, Songliao basin is carried out. The maceral content ranges from 0.7% to 15.8% by volume and with an average of 4.1%. There is great difference in maceral composition among the source rocks of different ages. The source rocks in Kn 2 to Kn 5 is lack of inertinite, but rich in vitrinite and relatively rich in exinite, showing high plant input domination. The source rock in Kn 1, comparatively rich in sapropelinite, showing a mixture input of algae and high plant input, is the main source rock. Alginite is the main hydrocarbon generating macerals for the low mature oil. Using vitrinite reflectance and the fluorescence parameters of sporinite, the thermal evolution of source is divided into unmature and low mature stage. The boundary corresponds to the 0.5% vitrinite reflectance, 2.2 relative fluorescence intensity I 546 of sporinite and 1050m in depth.