摘要
以江汉盆地江陵凹陷古近系新沟嘴组下段为主要研究对象,通过对不同地区原油生物标志化合物的组成与分布特征的分析,结合油—油、油—源对比发现研究区原油全部显示出成熟原油的特征并且形成于水体较深,还原性相对较强的沉积环境。根据生物标志化合物参数之间的差异,将研究区原油分为2类:Ⅰ类原油来自于万城地区以及南部地区,此类原油升藿烷系列含量极低,成熟度高并且陆源有机质贡献少;Ⅱ类原油全部来自于荆州背斜带,成熟度低于Ⅰ类原油,存在部分陆源有机质贡献,升藿烷系列化合物存在一定丰度,并且位于荆州背斜带西北部原油成熟度要明显大于中部及东南部。油源对比结果显示,2类原油在不同区域可能存在不同层位的烃源岩贡献,万城地区X-Ⅲ层位和X-Ⅱ层位烃源岩为Ⅰ类原油主要的烃源岩,同时荆州背斜带北部X-Ⅱ层位烃源岩对其也存在一定贡献;Ⅱ类原油主要以荆州背斜带北部X-Ⅲ层位为主要的烃源岩,荆州背斜带北部X-Ⅱ层位也存在一定的贡献,并且分布于荆州背斜带的中部及东南部的Ⅱ_2类原油中可能还存在万城地区2个层位烃源岩的些许贡献。
This paper takes the crude oils which are from Jiangling Depression＇s lower member of Xingouzui Formation as a main research object.Based on the analysis of the distribution and composition characteristics of biomarkers in different regions,and combining the oil-oil and oil-source correlation,it is found that all the crude oils in the study area show the characteristics of mature oil and formed in a relatively deep and highly reducible environment.According to the differences between the parameters of biomarkers,the crude oil in the study area is divided into two categories：The first kind of crude oil is from Wancheng area and the southern region,in this kind of crude oil,homohopane compounds content is very low and high maturity and less contribution of terrestrial organic matter;Another type of crude oil is from the Jingzhou anticline zone,its maturity is lower than the first kind of crude oil,it has some terrestrial organic matter contribution and there is a certain abundance of homohopane series compounds,and the oil maturity in the northwest of Jingzhou anticline zone is significantly greater than that in the central and southeastern part.The results of oil-source comparison show that the two types of crude oil may have the contribution of source rocks in different regions and different horizons：The first kind of crude oil is mainly from the X-III and XII of Wancheng area,and the source rocks which are from the X-II of northern Jingzhou anticline zone also have certain contribution to it.The second kind of crude oil is mainly from the X-II of northern Jingzhou anticline zone,and the X-II of northern Jingzhou anticline zone also have certain contribution to it,in addition,the crude oil in the central and southeastern part of the Jingzhou anticline zone may also have some contribution from the source rocks of the Wancheng area.
作者
李梦茹
唐友军
刘岩
胡辉
贺其川
Li Meng-ru;Tang You-jun;Liu Yan;Hu Hui;He Qi-chuan(School of Resources and Environment,Yangtze University,Wuhan 430100,China;Jingzhou Oil Production Plant,Jianghan Oilfield Branch Company,Jingzhou 434100,China)
出处
《天然气地球科学》
EI
CAS
CSCD
北大核心
2018年第9期1240-1251,共12页
Natural Gas Geoscience
基金
国家自然科学基金项目(编号:41730424)资助
关键词
江陵凹陷
原油
地球化学
油源对比
古近系
Jiangling Depression
Crude oil
Geochemistry
Oil-source correlation
Palaeogene
