鄂尔多斯盆地奥陶系盐下二氧化碳气藏成因分析  

Analysis of Genesis of Ordovician Subsalt COs Gas Reserevoir in Ordos Basin

作　　者：白海峰[1] 马占荣[1] 包洪平[1] 刘宝宪[1] 

机构地区：[1]中国石油长庆油田分公司勘探开发研究院

出　　处：《低渗透油气田》2012年第1期34-37,共4页

摘　　要：通过对CO2成因判识划分方法的对比，遵循科学性、实用性、通用性及简洁性的原则，采用通常的成因判识划分方法，对鄂尔多斯盆地龙探2井奥陶系盐下马家沟组马三段C02气体的成因进行了综合判识划分。龙探2井C02含量高近80％、碳同位素值δ13Cco为1．11%，而中国东部典型C02气藏的613Cco2均小于一2‰，所有火山喷发气体δ3Cco2也小于-2%。龙探2井δ13Cco2明显偏正，说明与东部C02气体的成因明显不同，幔源成因的可能性较小。龙探2井马三段白云岩储层δ13C值为1．26%，与C02气δ13CCO2的值近似相等，反映碳酸盐岩热解气成因的可能性更大。Through contrasting the existent commonly-used discrimination and division methods and according 1 the principles of science, practicability, common-use and succinctness, the geneses of the COz gas colleete from the Ordovician subsah Majiagou Formation Ma3 Member in well Longtan2 in the Ordos basin is discussed i the paper. The content of CO2 in the well Longtan2 is nearly 80% ,the carbon isotope value of CO2δ3Cco2）is 1.1 l%,and that of the emblematical CO2 gas in East China and all volcano eruptible gas is less than -2 %.The carbon isotope value of CO2δ13Cco2）in the well Longtan2 is obviously positive, showing the geneses of CO2 in the well Longtan2 is different from COs gas in East China, the possibility of mantle-geneses is very low. However the carbon isotope value of dolomite reservoir Ma3 Member in the well Longtan2 is 1.26%e, closeing to the value the carbon isotope value of COs （613Cco2） ,this reflect the geneses of the CO2 gas is possible carbonate pyrogena tion.

关 键 词：奥陶系盐下 CO2气藏 地球化学特征 成因分析 

分 类 号：P618.130.1[天文地球—矿床学]