鄂尔多斯盆地长7段页岩和泥岩生烃特征及其地质意义——以延安地区为例  

Hydrocarbon generation characteristics and geological significance of shale and mudstone in Chang 7 Member,Ordos Basin:a case study of Yan’an Area

作　　者：李钰 郭小波 时保宏 李艳霞 孙建博 刘刚 尹锦涛 张子羽 LI Yu;GUO Xiaobo;SHI Baohong;LI Yanxia;SUN Jianbo;LIU Gang;YIN Jintao;ZHANG Ziyu(School of Earth Sciences and Engineering,Xian Shiyou University,Xian,Shaancci 710065,China;Shaami Key Laboratory of Petroleum Accumulation Geology,Xian,Shaancci 710065,China;Research Institute of Shaami Yanchang Petroleum(Group)Company Limited,Xi'an,Shaanxi 710075)

机构地区：[1]西安石油大学地球科学与工程学院,陕西西安710065 [2]陕西省油气成藏地质学重点实验室,陕西西安710065 [3]陕西延长石油(集团)有限责任公司研究院,陕西西安710075

出　　处：《东北石油大学学报》2022年第5期106-114,I0007,共10页Journal of Northeast Petroleum University

基　　金：国家自然科学基金项目(41702127);国家科技重大专项(2017ZX05039-001);西安石油大学研究生创新与实践能力培养项目(YCS22113091)。

摘　　要：以鄂尔多斯盆地长7段泥岩和页岩为例,基于基本地球化学特征,开展封闭体系黄金管热模拟实验,分析泥岩和页岩生烃产率特征及黄铁矿对有机质生烃作用的影响。结果表明:在模拟温度为400℃之前,页岩气态烃产率高于泥岩的,最高相差43.06 mL/g,模拟温度继续升高后,泥岩气态烃产率超过页岩的;泥岩和页岩在350℃达到产油高峰,页岩总产油率比泥岩的高53.25 mg/g;黄铁矿可以显著提高页岩的C_(1)-C_(4)产率,并促进C_(5)的大量裂解,且黄铁矿可促进总油产率的增加,在产油高峰时,最大可增加54.17 mg/g。页岩生烃能力强,黄铁矿对页岩油气的生成具有一定促进作用;在采用原位加热方法开采页岩油气时,高黄铁矿质量分数的富有机质页岩层段是鄂尔多斯盆地延安地区长7段的首选目标。该结果对页岩油气勘探开发选区选层具有指导意义。Taking the mudstone and shale of Chang 7 Member in Ordos Basin as an example,based on the basic geochemical characteristics,the closed system gold pipe thermal simulation experiment was carried out to analyze the hydrocarbon generation characteristics of mudstone and shale and the influence of pyrite on the hydrocarbon generation of organic matter.The results show that before the simulation temperature is 400 ℃,the gas hydrocarbon yield of shale is higher than that of mudstone,with a maximum difference of 43.06 mL/g.After the simulation temperature continues to rise,the gas hydrocarbon yield of mudstone is higher than that of shale.Both mudstone and shale reach the peak of oil generation at 350 ℃,and the total oil production rate of shale is 53.25 mg/g higher than that of mudstone.Pyrite can significantly improve the C_(1)—C_(4) yield of shale and promote the large-scale cracking of C_(5), and pyrite can promote the increase of total oil yield,with the maximum increase of 54.17 mg/g at the peak of oil generation.The shale has strong hydrocarbon generation capacity,and pyrite can promote the generation of shale oil and gas.When in situ heating is used to exploit shale oil and gas,the organic rich shale interval with high pyrite content is the preferred target of Chang 7 Member in Yan’an Area,Ordos Basin.This achievement is of great significance to the formation selection in shale oil and gas exploration and development.

关 键 词：页岩油气 泥岩 页岩 生烃特征 黄铁矿 长7段 延安地区 鄂尔多斯盆地 

分 类 号：TE122[石油与天然气工程—油气勘探] P595[天文地球—地球化学]