贵州三都早奥陶世同高组下燕高页岩段的生物标志化合物  

Biomarkers From the Xiayangao Member of the Early Ordovician Tonggao Formation in the Sandu Area,Guizhou Province

作　　者：许玩宏[1,2] 张忠英[1,2] 沈平 孟仟祥[1,2] 

机构地区：[1]南京大学地球科学系 [2]中国科学院兰州地质研究所

出　　处：《沉积学报》1997年第3期72-77,共6页Acta Sedimentologica Sinica

基　　金：中国科学院兰州地质研究所气体球化学国家重点实验室和高等学校博士学科点专顶科研基金

摘　　要：本文着重报道了贵州三都早奥陶世同高组下燕高页岩段生物标志化合物特征，首次在采自该层位的样品中检出丰富的正烷烃、链状类异戊二烯烷烃、萜类化合物及甾类化合物。测试结果显示：正烷烃图谱呈双驼峰形，碳数分布为ｎＣ１５～ｎＣ３５，以ｎＣ１８为主峰碳，ｎＣ２９为次主峰碳，Ｃ－２１／Ｃ＋２２为０．７７～１．０２，ＯＥＰ为０．９４～１．０４；植烷占优势，Ｐｒ／Ｐｈ为０．４０～０．４６；藿烷碳数为Ｃ２７～Ｃ３５，以Ｃ３０占优势，Ｃ２７＋Ｃ２９＜Ｃ＋３１；仅见碳数分布为Ｃ２０～Ｃ２９的长链三环二萜烷，以Ｃ２８为主峰碳；甾烷丰度顺序为Ｃ２９甾烷＞Ｃ２７甾烷＞Ｃ２８甾烷，同时检出了孕甾烷和４－甲基甾烷。生物标志化合物显示出还原环境特点，且可能主要来自藻类。Abundant biomarkers(including n alkanes,acyclic isoprenoid,steranes and terpanes etc.)have been detected by GC MS from the Xiayangao Member of the Early Ordovician Tonggao Formation in the Sandu area of the Guizhou Provine.The carbon numbers of n alkanes range from nC 15 to nC 35 ,nC 18 as the highest peak and nC 29 as the second,nC + 21 /nC + 22 ratios are up to 0.77￣1.02,and OEP=0.94￣1.04.Phytane is predominant over priatane with a Pr/Ph of 0.40￣0.46(average 0.44).Hopane series consist mainly of C 27 ￣C 35 hopanes,a mong which C 30 hopane is the most abundant one,and hopane C 27 +C 29 <C + 31 .Tricyclic terpanes are only composed of long chain ones their carbon numbers ranging from C 20 to C 29 ,and strong predominance of C 23 is detected,Steranes consist mainly of C 27 sterane,C 23 sterane and C 29 sterane.According to abundance,C 29 sterane>C 27 sterane>C 28 sterane,pregnance and 4 methy1 steranes are also identified.The composition and distribution of n alkanes,acyclic isopenoid,terpanes and steranes,combining with the biota occurring in the same rock samples,seem to show the characteristics of a reduction environment,and the biomarkers detected from the rock samples might mainly originate from algae.

关 键 词：生物标志 化合物 早奥陶世 同高组 页岩段 

分 类 号：Q915.642[天文地球—古生物学与地层学] P588.311[生物学—古生物学]