松辽盆地边缘石炭-二叠系地表石油显示及其地质意义

Show of petroleum of C-P systems on the earth's surface at the edge of Songliao basin and its geological significance

在龙江地区野外实测剖面的岩石裂缝中发现了二叠系的石油显示,在单偏光镜下颜色呈黑褐色,在荧光镜下显示棕黄色或绿色;油源追踪研究证明,野外发现的二叠系干沥青是由石炭二叠系岩石本身生成的,而不是来自于盆地上部的其他生油气岩层。这一发现和研究对松辽盆地深层的油气勘探具有实际意义。

Four dry bitumens,or oil seepages,f rom Permian System are discovered in the cracks of siltstone-packsand and carbonate rocks of a mea sured section in the field at Longjia ng area.The color of the dry bitumen samples is black-brown under single polar,but brown yellow and green under fluoroscopy.In addition,these oiliness-bitumen samples have medi um luminous intensity.The dry bitum en samples of Permian System are analyzed for carbon number distribution of normal-alkanes,characteristic para meters of saturated hydrocarbons,i nfrared spectra and steroids-terpenoids co mpounds characteristics.Moreover,the results are compared with the ma in source rocks of Carboniferous-Permian(C-P)and Cretaceous(K).The result of oil-source rocks correlation shows that the dry bitumen samples discovered in th e field are generated by C-P system strata themselves,not coming from oth er source rocks of upper strata such as Cretaceous in the basin.In addition,the generation-migration-accumul ation processes of petroleum were surely e xisted in C-P systems in the geologic al history.The discovery and the stu dy are of important significance to the exp loration of oil and gas in the deep str ata of Songliao basin.