海相地层无机参数与烃源岩发育环境的相关研究——以鄂尔多斯盆地为例  

Study on relation between inorganic parameters in marine deposits and developmental environment of hydrocarbon source rocks:taking Ordos basin as an example

作　　者：腾格尔[1] 刘文汇[2] 徐永昌[3] 陈践发[4] 胡凯[1] 高长林[5] 

机构地区：[1]南京大学地球科学系,江苏南京210093 [2]中国石化石油勘探开发研究院,北京100083 [3]中国科学院兰州地质所,甘肃兰州730000 [4]中国石油大学,北京102249 [5]中国石化石油勘探开发研究院无锡石油地质研究所,江苏无锡214151

出　　处：《石油与天然气地质》2005年第4期411-421,共11页Oil & Gas Geology

基　　金：国家重点基础研究发展规划(973)项目(2001CB209102;G1999043306);中国石化股份公司科技项目(P04040)

摘　　要：运用无机与有机参数组合对鄂尔多斯盆地海相烃源岩发育环境的研究表明,有机碳含量大于0.2%层段其V/(V+N i)>0.5,Zr/Rb<2,Rb/K>30×104,古盐度大于122,Zn,Mo,Ba等富集,δ18O,δ13C碳酸盐正向偏移,指示低能、缺氧环境,具良好的有机质保存条件,有较高的生物生产力和有机质埋藏量,其δ13C有机质<-28‰,有机质类型好(Ⅰ-Ⅱ型),生烃潜力高,可视为潜在有效烃源岩;有机质碳含量大于等于0.2%层段的有机、无机地化特征均反映高能、氧化环境,有机质保存条件差,埋藏量低,δ13C有机质值为-28‰^-24‰,多属Ⅱ-Ⅲ型母质,生烃潜力差,属非有效烃源岩。微量元素及碳氧同位素对烃源岩发育的主控因素具良好的表征意义,可作为烃源岩发育环境的判识指标,结合必要的有机参数可以进一步识别有效烃源岩。The paleoenvironment of Ordovician in southwestern Ordos basin are discussed by using both inorganic and organic parameters, trying to identify potential hydrocarbon source rocks. In the strata with TOC〉0.2%, V/（V＋Ni）〉0.50, Zr/Rb 〈2, Rb/K 〉30×10^4, Z〉122, Zn,Mo and Ba are enriched, and the δ^18Corg and δ^13Ccarb have positive excursion. These characteristics indicate a stagnant and anoxic sedimentary environment with higher organic matter productivity and better preservation condition. These strata have δ^13Corg〈-28‰（Ⅰ-Ⅱ type kerogen） , and high hydrocarbon-generating potential, so they can be regarded as potential hydrocarbon source rocks. The strata with TOC≤0.2% whose inorganic and organic parameters show a high energy, oxic, littoral-neritic environment with δ^13Corg between -24% and -28‰（ Ⅱ-Ⅲ type kerogen） have low hydrocarbon-generating potential. Such environment is unfavorable for preservation of organic matters, and development of hydrocarbon source rocks. The integration of inorganic parameters （trace element, stable isotope composition etc. ） with general organic data can be regarded as important environmental factors for identifying development of effective marine hydrocarbon source rocks.

关 键 词：发育环境 判识指标 无机参数 海相烃源岩 鄂尔多斯盆地 

分 类 号：TE112.1[石油与天然气工程—油气勘探]