准噶尔盆地滴南凸起含油储集岩分子与碳同位素地球化学研究

从滴南凸起10个含油储集岩样品分步提取了自由态油气组分、束缚态油气组分和油气包裹体组分,各组分进一步做色谱、色谱-质谱和正构烷烃单体碳同位素分析。根据生物标志物组成,可将10个含油储集岩样分为两类：第一类包括D2-1和D18-12个侏罗系油砂样,第二类包括其他8个采自侏罗系、二叠系和石炭系含油储集岩样。两类样品生物标志物组成差异主要有：（1）第一类样品各类油气组分三环萜烷含量明显低于第二类样品；（2）第一类样品 C20、C21和 C23三环萜烷含量比较接近,其分布模式为 C20＆lt;C21＆gt;C23,第二类样品这3个化合物含量差异较大,且分布模式为C20＆gt;C21＆gt;C23；（3）第一类样品伽马蜡烷和β-胡萝卜烷相对含量高于第二类样品；（4）第一类样品C27甾烷含量较低而C28甾烷含量较高,第二类样品则相反。可以推断第一类样品自由态组分、束缚态组分和油气包裹体均来源于二叠系烃源岩而第二类样品各类油气组分则来源于石炭系烃源岩。第一类样品油气包裹体成熟度明显高于自由态组分和束缚态组分,表明早期充注原油的成熟度高于晚期充注的原油,总体上各类油气组分成熟度位于生油高峰阶段（Ro 0.8%~1.1%）。第二类样品从自由态组分、束缚态组分至油气包裹体成熟度依次降低,表明早期充注原油的成熟度低于晚期充注的原油,总体上各类油气组分成熟度位于高-过成熟阶段（Ro〉1.25%）。第一类样品各类油气组分正构烷烃单体碳同位素组成相对较轻,第二类样品各类油气组分正构烷烃单体碳同位素组成有一定的差异,组成较轻者与第一类样品各类油气组分接近。

Molecular and carbon isotopic compositions of oil components in reservoir rocks from Dinan uplift,the Junggar Basin

Free oils, adsorbe d oils and inclusion oils were obtained by sequential extraction from ten oil-containing reservoir rocks from the Dinan uplift, the Junggar Basin, and further analyzed by GC, GC-MS and GC-IRMS. According to the analytical results, the ten oil-containing reservoir rocks can be classified into two types. Type 1 includes two Jurassic oil sandstones D2-1 and D18-1 while type 2 includes the other eight reservoir rocks from the Jurassic, Permian and Carboniferous strata. The major differences in biomarker compositions between oil components in the two type samples are as follows： （1） oil components contain substantially lower amounts of tricyclic terpanes in type 1 samples than type 2 samples;（2） the amounts of C20, C21 and C23 tricyclic terpanes only＆amp;nbsp;differ slightly with a distribution pattern C20〈C21〉C23 in oil components of type 1 samples while they differ substantially with a distribution patter C20〉C21〉C23 in oil components of type 2 samples; （3） oil components contain higher amounts of gammacerane and β-carotane in type 1 samples than type 2 samples; and （4） oil components in type 1 samples contain lower amount of C27 sterane and higher amount of C28 sterane while those in type 2 samples are opposite. It can be determined that oil components in type 1 samples were derived from the Permian source rocks while those in type 2 samples were derived from the Carboniferous source rocks. For type 1 samples, the inclusion oils have higher maturities than the free and adsorbed oils, demonstrating that oil maturities decreased during reservoir filling process. The maturities of oil components in type 1 samples are generally in the peak oil generation stage （Ro 0.8%~1.1%）. For type 2 samples, the maturities decrease from the free oil, through the adsorbed oil, to the inclusion oil, demonstrating that the oil maturities increased during reservoir filling process. The maturities of oil components in type 2 samples are in high and post maturation stages （Ro〉1.25%?