柴西油沙山地区油沙有机地球化学特征研究  

Organic geochemical signatures of the oil sands from the Youshashan area,western Qaidam Basin,Qinghai

作　　者：宋红莎 韩梅梅[3,4] 曹占元 张晓宝[2] 陈文磊[2] SONG Hong-sha;HAN Mei-mei;CAO Zhan-yuan;ZHANG Xiao-bao;CHEN Wen-lei(Key Laboratory of Petroleum Resources,Gansu Province/Key Laboratory of Petroleum Resources,Chinese Academy of Sciences,Lanzhou 730000,Gansu,China;University of the Chinese Academy of Sciences,Beijing 100081,China;Institute of Geomechanics,Chinese Academy of Geological Sciences,Beijing 100081,China;China University of Geosciences,Beijing 100083,China)

机构地区：[1]甘肃矿业开发研究院,甘肃兰州730000 [2]甘肃省油气资源研究重点实验室/中国科学院油气资源研究重点实验室,甘肃兰州730000 [3]中国地质科学院地质力学研究所,北京100081 [4]中国地质大学,北京100083

出　　处：《沉积与特提斯地质》2018年第1期96-102,共7页Sedimentary Geology and Tethyan Geology

基　　金：中国科学院2012年度"西部之光"人才计划支持项目"马海地区深层构造特征及油气藏成因类型研究"(1308RJZA310);甘肃省重点实验室专项(1309RTSA041)联合资助

摘　　要：为深入研究油沙山地区油沙的古沉积环境、成熟度及母质来源,促进柴西地区非常规资源勘探开发,本文以油沙山干柴沟组油沙为研究对象,通过气相色谱-质谱分析,发现该区油沙正构烷烃受到轻度损失,降解程度为1级;该区油沙具有低的m(Ts)/m(Tm)值,相对低的m(C29ββ)/m[(ββ+αα)]和m(C29ααα-20S)/m[20(S+R)]的值,表明油沙油属低成熟油沙油;m(Pr)/m(Ph)较低,表明其源岩沉积强还原环境;油沙油样品具较高的m(r-蜡烷)/m(0.5C31)值,显示为高盐度咸水环境沉积;甾烷C27、C28和C29参数成"L"型或"V"型分布,表明油沙油母质来源水生生物相对较多。The oil sands resources are interpreted as the significant unconventional oil and gas resources in China.The emphasis of the present paper is placed on the chromatographic analysis and mass spectrographic analysis of eight pieces of oil sands samples from the Upper Ganchaigou Formation（ N1） in the Youshashan area in order to examine ancient sedimentary environments,maturity and origin of parent matter types. The results in this study show that the saturated hydrocarbons range between 0. 53 and 0. 81,indicating higher oil contents. The m（ Pr）/m（ Ph） ratios vary from 0. 43 to 0. 26,with an average of 0. 32（ 8）,indicating a relatively deep-water and highly reducing environment of the source rocks. The parameters for oil sands evolution m[C31αβ22 S/22（ S ＋ R） ]and m[C32αβ22 S/22（ S ＋ R） ]are more than 0. 5 or 0. 6,indicating that all the eight oil sands samples are maturated oil sands samples and subjected to biodegradation. The triangular diagram of the parameters of steranes C27,C28 and C29 indicate that the parent matter types of the oil sands belong to the lower aquatic organisms mixed with higher plants. The oil sands in the study area have higher contents of saturated hydrocarbons,wider outcropped area and greater thickness,and thus may be considered highly prospective for the unconventional oil and gas resources.

关 键 词：油沙 地球化学 母质类型 沉积环境 成熟度 

分 类 号：TE122[石油与天然气工程—油气勘探]