昝灵 1张枝焕 2王顺华 3邢辉 2李文浩 2刘祎楠 4席伟军5
作者信息
- 1. 中国石油化工股份有限公司华东分公司石油勘探开发研究院,南京210011
- 2. 中国石油大学油气资源与探测国家重点实验室,北京102249
- 3. 中国石油化工股份有限公司华东胜利油田石油开发中心,山东东营257000
- 4. 西北大学地质系,西安710069
- 5. 中国石油化工股份有限公司华东胜利油田新疆勘探开发中心,山东东营257000
- 折叠
摘要
Abstract
Because of the samilar paleoclimate and palosedimentary environment,regular biomarkers and isotope distinction of the source rocks and generated petroleum in the sub-sag belong to the same sag is tiny,which bring difficulties to oil-source correlation.By extracting molecular fossils information using GC-MS technology,according to the relative content of 4-methyl steranes and distribution characteristics of 4-methyl steranes isomers,oil-source correlation work are performed,which provides a new method for oil-source correlation in similar area.Es4s and Es3x two sets of source rocks are developed in the study area,they are characterized by high organic matter abundance,mature to over mature thermal evolution degrees.Organic matter of Es4s are formed in brackish-saline water with reductive environment,organic matter of Es3x are formed in fresh-saline water with reductive environment,organic matter input of both source rocks are dominated by lower aquatic organisms and terrigenous higher plants,while terrigenous higher plants are more abundant near provenance.Relative content of 4-methyl steranes of Es3x source rocks is higher than that of Es4s source rocks,indicating the better organic matter input of Es3x source rocks.The value of 4-methyl steranes/C29 steranes of Es3x source rocks in the middle,west and deep sub-sag is 4.51,2.79 and 1.27,respectively,which is caused by the different proportion of dinophyceae in total organic matter.The distribution characteristics of C20,C21,C23 tricyclic terpanes and ααα20RC27,C28,C29regular steranes of oils with alike maturity in different region is quite similar,4-methyl steranes/C29steranes value of crude oils in the middle,west and east region is 2.89,2.39,2.06,respectively,which make a big difference,while the carbon isotope characteristics of crude oils are opposite,distribution characteristics of 4-methyl steranes isomers of each region is also different.Oil-source correlation demonstrate that Es4s and Es3x crude oils of northern steep slope zone mainly originate from Es3x source rocks in nearby sag,crude oils of the western zone are provided by Es3x source rocks of the western sag,crude oils of the middle zone are provided by Es3x source rocks of the middle sag,crude oils of the eastern zone are provided by Es3x source rocks of deep sag in the eastern zone,and no contribution from source rocks of the Gubei Sag.关键词
4-甲基甾烷/渤南洼陷/北部陡坡带/生物标志化合物/油源分析Key words
4-methyl sterane/Bonan sag/northern steep slope zone/biomarker/oil-source correlation分类
天文与地球科学
