准南霍玛吐背斜带原油地球化学特征及油源分析

Geochemical Characteristics of Crude Oil of Huomatu Anticline Zone in the Southern Junggar Basin and Its Oil Source Correlation

准噶尔盆地南缘霍玛吐背斜带油源丰富,成藏条件良好,在古近系、新近系均获高产工业油气流。通过对准噶尔盆地南缘霍玛吐背斜带原油或油砂抽提物饱和烃与芳烃气象色谱-质谱分析,研究了原油及油砂抽提物中的族组成、正构烷烃、类异戊二烯烷烃以及甾萜烷系列化合物的分布特征,并结合碳同位素特征,对原油类型进行了划分,且对油源做了初步的分析。研究表明,霍玛吐背斜带原油可划分为2种类型:A类原油主要分布于霍尔果斯背斜、玛纳斯背斜、吐谷鲁背斜、安集海背斜、呼图壁背斜,其地球化学特征与白垩系烃源岩相似;B类原油主要分布在独山子背斜,主要来源于古近系安集海河组烃源岩。

Huomatu anticline zone in the Southern Junggar Basin obtains commercial oil flow with high production from the Paleogene and Neogene with abundance oil sources and favorable conditions of hydrocarbon accumulation.The geochemical characteristics of saturated and aromatic hydrocarbons from crude oils or core extracts in the Huomatu anticline zone are investigated by gas chromatography-mass spectrum analysis.The types of crude oil are divided and oil-source correlations are analyzed preliminarily through the biomarkers such as group composition,n-alkanes,isoprenoids,terpanes and steranes.Combined with carbon isotope characteristics,crude oils or core extracts are divided into two different types:Type A of crude oil occurs in Huoerguosi,Manasi,Tugulu,Anjihai and Hutubi Anticlines and Type B oil only occurs in Dushanzi Anticline.The correlation between oils and source rocks reveals that Type A oil is mainly derived from the cretaceous hydrocarbon source rock,and Type B oil mainly from the source rocks of Anjihaihe Formation in Paleogene.