抚顺盆地始新统计军屯组油页岩地球化学特征及其地质意义  

Geochemical characteristics of oil shale of Eocene Jijuntun Formation and its geological significance, Fushun basin.

作　　者：刘招君[1,2] 孟庆涛[1,2] 柳蓉[1,2] 董清水[1,2] 

机构地区：[1]吉林大学地球科学学院,长春130061 [2]东北亚生物演化与环境教育部重点实验室,长春130026

出　　处：《岩石学报》2009年第10期2340-2350,共11页Acta Petrologica Sinica

基　　金：国土资源部公益性行业科研专项(批准号:200811013);国家自然科学基金项目(批准号:40972076);全国油气资源战略 选区调查与评价国家专项(2009GYXQ11);高等学校博士学科点专项科研基金(新教师基金课题)(批准号:200801831098)的资助.

摘　　要：本文在野外实测剖面基础上,对抚顺盆地始新统计军屯组油页岩开展较为详细的地球化学特征研究,根据微量元素富集程度、元素比值变化及生物标志化合物特征等,探讨了油页岩的有机母质来源、沉积环境及其对油页岩成矿的控制。油页岩中微量元素主要有Li、Ti、Co、Cr、Cu、Ni、Pb、V、Mn、Sr、Ba、Zn、Ga、Rb和Cd。有机碳含量较高,平均为12.90%,氯仿沥青"A"组成中饱和烃馏分占优势,有机质以腐泥型为主。样品中检测出丰富的正构烷烃、类异戊二烯烷烃、甾类化合物和萜类化合物。在GC谱图上,正构烷烃呈"前低后高"双峰式分布,主峰碳数分别为nC_(17)或nC_(27)、nC_(19)或nC_(27),nC_(31)/nC_(17)为1.12～17. 38,重烃组分占优势,CPI值为1.55～1.77,OEP值为1.61～1.81,Pr/Ph为1.53～2.08。甾类化合物以规则甾烷为主,其次为重排甾烷,孕甾烷丰度极低,规则甾烷C_(27_-C_(28)-C_(29)ααα20R构成近对称的"V"字型,∑(C_(27)+C_(28))/∑C_(29)比值为1.11～1.19,∑C_(27)/∑C_(29)比值为0.63～0.77。萜类化合物以C_(30)藿烷占优势的五环三萜烷为主,含少量三环萜烷,检出少量奥利烷,几乎未见四环萜烷和伽马蜡烷。元素丰度及饱和烃色谱/质谱特征表明抚顺油页岩有机母质来源具水生生物和高等植物双重生源特征;Sr/Ba、V/V+Ni等元素比值,结合生物标志化合物特征及野外地质观察,揭示油页岩形成于淡水缺氧半深湖-深湖环境。湖泊自身生产力为油页岩的形成提供了主要的有机母质来源,稳定缺氧环境有利于有机质的堆积和保存。Based on the actual field geological profile, this paper aims to develop detailed research on geochemical characteristies of oil shale in Jijuntun Formation of Eocene in Fushun Basin. The origin of organic matters, sedimentary environment and their control action on oil shale mineralization have been discussed, according to the study of the enrichment degree of trace element, element ratios and the characteristics of biomarkers. Trace element of oil shale includes Li, Ti, Co, Cr, Cu, Ni, Ph, V, Mn, Sr, Ba, Zn, Ga, Rb and Cd. Oil shale is characterized by high organic carbon content, with the average of 12.90%. Among the composition of chloroform bitumen 'A', saturated hydrocarbon is more advantaged, and the organic matters are sapropelic. Abundant biomarkers, including n-alkanes, isoprenoid, steranes and terpanes from oil shale have been detected by GC and GC-MS. The n-alkanes have the features of double-peak distribution, with the back peak much higher than the front one and nC(17) or nC(27) nC(19) or nC(27) as the mean peaks. The nC(31)/nC(17) ratios of 1.12 to 17.38 show the predominance of heavy hydrocarbon in the n-alkanes. CPI values vary from 1.55 to 1.77, OEP from 1.61 to 1.81, and Pr/Ph from 1.53 to 2.08. In the m/z217 GC-MS, regular steranes are characterized by highest abundances, rearranged steranes by the second, and minor Pregnane is presented. The regular steranes C(27)-C(28)-C(29) alpha alpha alpha 20R distributes with 'V' shape, and Sigma(C(27) + C(21))/Sigma C(29) ratio varies between1. 11 and1. 19. In the m/z191 GC- MS, C(30) hopane is most abundant in the terpanes, and minor tricyclic terpanes and oleanane are present, tetracyclic terpane and gammacerane are hardly be seen. Element abundance and GUMS characteristics of saturated hydrocarbon show that the organic matters are characterized by double origins from aquatic organisms and higher plants. Element ratios such as Sr/Ba, V/V + Ni et al., combined with the characteristics of biomarkers and field observation, reveal that oil shale forms in

关 键 词：抚顺盆地 统计 军屯 油页岩 地球化学特征 地质意义 geological significance 生物标志化合物 母质来源 甾类化合物 萜类化合物 正构烷烃 甾烷 元素比值 中微量元素 类异戊二烯烷烃 有机质 优势 环境 饱和烃 

分 类 号：P58[天文地球—岩石学]