塔河油田原油三环萜烷异常分布特征及成因探讨  

Abnormal Distribution of Tricyclic Terpanes and Its Genesis in Crude Oils from Tahe Oilfield

作　　者：敖添 王作栋 张婷 李晓斌 王文军 马冬晨[3] 贾星亮[4] 王丹[3] AO Tian;WANG ZuoDong;ZHANG Ting;LI XiaoBin;WANG WenJun;MA DongChen;JIA XingLiang;WANG Dan(Northwest Institute of Eco-Environmental Resources,Chinese Academy of Sciences,Gansu Provincial Key Laboratory of Oil and Gas Resources Research,Lanzhou 730000,China;University of Chinese Academy of Sciences,Beijing 100049,China;Experimental Testing Technology Center,SINOPEC Northwest Oilfield Company,Urumqi 830011,China;SINOPEC Key Laboratory of Fracture-cavity Reservoir Enhanced Oil Recovery,Urumqi 830011,China)

机构地区：[1]中国科学院西北生态环境资源研究院,甘肃省油气资源研究重点实验室,兰州730000 [2]中国科学院大学,北京100049 [3]中国石化西北油田分公司实验技术测试中心,乌鲁木齐830011 [4]中国石化缝洞型油藏提高采收率重点实验室,乌鲁木齐830011

出　　处：《沉积学报》2023年第4期1202-1211,共10页Acta Sedimentologica Sinica

基　　金：国家自然科学基金项目(41772133)。

摘　　要：塔河油田是我国目前原油储量最大的古生界海相碳酸盐岩油气田,其原油中三环萜烷含量异常丰富,并显著高于藿烷。对塔河90个原油样品的气相色谱和气相色谱—质谱数据进行分析,从沉积环境、生物降解和成熟度三个方面,探讨了塔河原油中三环萜烷异常分布的特征和成因。结果表明,烃源岩的形成环境、有机质沉积时水体的氧化还原条件和咸化程度,均不是塔河原油中三环萜烷相对丰度高于藿烷的主要影响因素;三环萜烷相对丰度不同的原油生物降解程度无较大差异,表明生物降解是一个较为次要的影响因素;而有机质中细菌输入增多会导致三环萜烷相对丰度的增加。此外,成熟度越高的原油三环萜烷相对丰度越高,Σ三环萜烷/Σ17α(H)-藿烷比值与成熟度参数C27重排/常规甾烷呈良好的正相关关系,表明成熟度是塔河原油中三环萜烷异常分布的主要影响因素。Tahe oilfield is the Paleozoic marine carbonate oil and gas field with the largest crude oil reserves in China.The content of tricyclic terpanes in Tahe crude oil is unusually rich and significantly higher than hopanes.The reason for this abnormal distribution is still unclear.In this study,gas chromatography and gas chromatography-mass spectrometry(GC-MS)data for crude oil samples from Tahe oilfield were analyzed.The abnormal distribution and genesis of tricyclic terpanes in Tahe crude oil are discussed,covering deposition environment,biodegradation and thermal maturity.The results show that for the deposition environment,the degree of oxidation-reduction and salinization during deposition of organic matter is not the main reason.However,the relative content of tricyclic terpanes increased with increasing bacterial input in organic matter and thermal maturity.Σtricyclic terpanes/Σ17α(H)-hopanes is positively correlated with thermal maturity,indicating that thermal evolution was the most significant driving force for the abnormal distribution of tricyclic terpanes in Tahe crude oils.

关 键 词：三环萜烷 藿烷 成熟度 原油 塔河油田 

分 类 号：P618.13[天文地球—矿床学]