Abstract: More than 200 aromatic compounds and 13 aromatic series of hydrocarbons such as biphenyl,naphthalene,phenanthrene,carbazole were found in six kinds of light oil samples from five wells in Panyu Lower Uplift of Pearl River Mouth Basin by using GC-MS analytical technique.The geochemistry characteristics of aromatic hydrocarbon in light oils were analyzed in detail.The results show that distributions of aromatic compounds in the light oils from Well L1 and Well P1 are different from those of Well P2,Well P3 and Well P4.The light oil samples from Well L1 and Well P1 contain more dibenzofuran and fluorence hydrocarbons and less naphthalene hydrocarbons.Meanwhile,the diversity of relative contents between biphenyl and naphthalene in two groups of light oils is apparent.The contents of fluorine,dibenzothiophene and dibenzofuran also show difference of sedimentary environment.The origin of light oils from Well L1 and Well P1 is different from that of Well P2,Well P3 and Well P4.It is suggested that the light oils from Well L1 and Well P1 derived from the lacustrine shales in Wenchang Formation or from the mixed source of Wenchang Formation and Enping Formation,while the light oils from Wells P2,Wells P3 and Wells P4 mainly originated from the source rocks in the Enping Formation.The maturity parameters of methylnaphthalenes,methylphenanthrene and methylcarbazole from the aromatic hydrocarbons of light oils indicated that the maturity degrees of light oils reached the high-maturity stage.

Key words: Pearl River Mouth Basin, light oil, aromatic hydrocarbon compound, oil-source analysis, oil maturity, geochemistry characteristics

摘要： 采用GC-MS分析技术,在珠江口盆地番禺低隆起5口井6个轻质原油样品中检测到了联苯、萘、菲、二苯并噻吩等13个系列200多种化合物,详细分析了轻质原油芳烃地球化学特征。L1井和P1井轻质原油与P2、P3和P4 3口井的轻质原油芳烃化合物的分布特征差异较大,L1井和P1井轻质原油样品中具有二苯并呋喃和芴系列化合物含量高、萘系列化合物含量低的特征,而且这两类轻质原油的联苯系列和萘系列化合物相对丰度关系存在明显差异,芴、硫芴和氧芴含量也表明了两者之间沉积环境的差异。这都表明L1井和P1井轻质原油与P2、P3和P4 3口井的轻质原油的来源不同。P2、P3和P4 3口井轻质原油母源为恩平组烃源岩,而L1井和P1井2个轻质原油可能主要来自于文昌组湖相泥岩,或者为文昌组和恩平组烃源岩两者混合来源。芳烃中甲基萘、甲基菲和甲基二苯并噻吩成熟度参数反映番禺低隆起轻质原油样品成熟度已经处于高成熟演化阶段。

关键词: 珠江口盆地, 轻质原油, 芳烃化合物, 油源分析, 原油成熟度, 地球化学特征