摘要
采用饱和烃气相色谱、色谱-质谱技术,研究大兴安岭北部拉布达林盆地中生代烃源岩生物标志化合物特征,探讨有机质来源、热演化程度、沉积环境。结果表明:拉布达林盆地中生代烃源岩有机质丰度较高,有机质为Ⅰ型和Ⅱ1型干酪根,以混合来源为主,低等的水生物输入占优势,伴有一定的陆生高等植物输入;Pr/Ph为0.58~0.68,植烷的优势明显,倍半萜烷中8β(H)-升补身烷的丰度高于8β(H)-重排补身烷的,反映烃源岩形成于水体较深的还原环境;伽马蜡烷指数为0.29~0.33,沉积水体为具有一定盐度的微咸水沉积环境;(C20TT+C21TT)/(C23TT+C24TT)、C24TET/C26TT丰度分别为0.67~0.90、0.44~0.54,显示咸水湖相烃源岩的特征;Ts/Tm、C29甾烷ββ/(ββ+αα)、C29甾烷20S/(20S+20R)丰度分别为0.72~0.92、0.43~0.44、0.47~0.49,反映烃源岩热演化程度较高。研究区中生代烃源岩形成于水体较深的微咸水还原条件下的古沉积环境,有利于有机质保存,整体为中等-好烃源岩,有机质以混合来源为主,热演化程度较高,具有一定的生烃潜力。
Based on saturated hydrocarbon gas chromatography and chromatography-mass spectrometry,the characteristics of biomarker compounds of the Mesozoic source rocks in Labudalin Basin,Northern Daxinganling Mountains are investigated.Information as the sources,thermal evolution degree of organic matter and sedimentary environment in source rocks are analyzed.The result shows that the Mesozoic source rocks in Labudalin Basin source are rich in organic abundance,the kerogen type of organic matter is byⅠtype andⅡ1 type,organic matter as a mixed sources are lower aquatic organisms mixed with higher terrigenous plants.The ratio of Pr/Ph ranges from 0.58 to 0.68,which shows a distinct advantage on phytane;the content of 8β(H)-homodrimane is higher than 8β(H)-rearranged drimanes in sesquiterpenoids,which reflects that the source rocks are formed in the reductive environment with deeper water;the ratio of gammacerane index ranges from 0.29 to 0.33,indicating that sedimentary water body is a brackish sedimentary environment with certain salinity;the ratio of(C20 TT+C21 TT)/(C23 TT+C24 TT)and C24TET/C26 TT respectively ranges from 0.67 to 0.90 and 0.44 to 0.54,indicating the characteristics of source rocks in the lacustrine facies;the ratio of Ts/Tm ranges from 0.72 to 0.92,the ratio of C29-αββ/(αββ+ααα)ranges from 0.43 to 0.44 and the ratio of C29-ααα20 S/(20 S+20 R)ranges from0.47 to 0.49,it reflects the high degree of thermal evolution of source rocks.It is concluded that the Mesozoic source rocks in Labudalin Basin,Northern Daxinganling Mountains,were formed in the paleosedimentary environment of brackish deeper water under the reduction,which is favorable for the preservation of organic matter,the whole is medium to good source rocks,organic matter as a mixed sources,higher degree of thermal evolution,showing that it has good potential for hydrocarbon generation.
作者
孙雷
莫少武
宗文明
卞雄飞
张健
苏飞
何大祥
SUN Lei;MO Shaowu;ZONG Wenming;BIAN Xiongfei;ZHANG Jian;SU Fei;HE Daxiang(Shenyang Center of Geological Survey,Chirna Geological Survey,Shenyang,Liaoning 110034,China;School of Resources and Environment,Yangtze University,Wuhan,Hubei 430100,China)
出处
《东北石油大学学报》
CAS
北大核心
2019年第6期73-82,I0005,I0006,共12页
Journal of Northeast Petroleum University
基金
国家自然科学基金项目(41790451)
中国地质调查局项目(DD20190097)
中国地质调查局项目(DD20160163)
