【摘要】 对塔里木盆地塔中地区6个志留系沥青砂岩样品中的孔隙游离烃和包裹体烃,做了分离并分别进行了色-质分析。色-质分析表明孔隙游离烃和包裹体烃具有显著不同的特征:前者表现为前峰型轻质烃特点,主峰碳较小(为nC16或nC20),无奇碳优势,多伴有生物降解现象;而后者多表现出双峰分布特征,主峰碳数较大(为nC25或nC29),有一定奇碳优势。在生物标志物上,孔隙游离烃三环萜烷和孕甾烷含量都较高,C27,C28和C29甾烷呈不对称“V”字型分布;而包裹体烃的三环萜烷和孕甾烷含量都较低,C27,C28和C29甾烷呈斜线上升型分布。油源对比表明,沥青砂岩包裹体中捕获的烃与中-下寒武统烃源岩有关,而孔隙游离烃则与中-上奥陶统烃源岩有关。更多还原

【Abstract】 Pore free hydrocarbons and inclusion hydrocarbons in 6 Silurian bituminous sandstone samples from the Tazhong area of Tarim basin are separated and analyzed with GC and GC-MS.The analysis results show that pore free hydrocarbons and inclusion hydrocarbons have different characteristics.The pore free hydrocarbons are represented by light hydrocarbons of pre-peak distribution and peak carbon number at nC16 or nC20,without odd carbon number predominance,which are usually associatee with significant biodegradation.The inclusion hydrocarbons are represented by heavy hydrocarbons of bimodal distribution and peak carbon number at nC25 or nC29,with odd carbon number predominance.In respect of biomarker,the pore free hydrocarbons have a relatively high concentration of tricyclic terpanes and pregnane,with the C27,C28 and C29 steranes of asymmetrical "V" distribution;whereas the inclusion hydrocarbons have a relatively low concentrations of tricyclic terpanes and pregnane,with the C27,C28 and C29 steranes of oblique-ascending distribution.Oil-source correlation indicates that the hydrocarbons entrapped in the inclusions of bituminous sandstone might be sourced from the Middle-Lower Cambrian source rocks,while the pore free hydrocarbons might be generated by the Middle-Upper Ordovician source rocks.更多还原