摘要
通过玛湖凹陷风城组湖相泥岩与泥质白云岩加水热模拟试验气态和液态产物组成、产率的对比,分析了气态和液态产物组成、产率随模拟温度的变化特征。结果表明：热模拟的烃类气体相对含量随模拟温度升高表现为增加趋势,而非烃类气体则降低;气体组成表现为泥质白云岩的CO2含量低于泥岩,其他组分含量则相反;各样品的气体产率均随模拟温度升高而持续增加,生油高峰温度主要在330℃~350℃之间,这明显低于干法热模拟,与实际地质条件下的温度更接近;烃源岩中含有碳酸盐对生成石油比天然气更有利;试验条件下的CO2主要为有机成因,但也有碳酸盐的热分解贡献。气态烃的碳同位素组成总体变化幅度较小,各温度点均表现为油型气特征;排出油与残留油的正构烷烃主峰碳数、相对高碳数烃的相对含量总体随模拟温度升高而降低;各样品残留油与排出油的生物标志物参数均有一定变化,在进行油源对比时应考虑这种变化的影响。
Based on contrast of composition and yield of gaseous and liquid thermal simulation experiment products of mudstone and argillaceous dolomite from Fengcheng Formation in Mahu sag,Junggar Basin,the variation features of the liquid and gaseous products with simulation temperature increasing were discussed.The results show that the relative content of thermal simulation gaseous hydrocarbon increases with the rise of simulation temperature,and the nonhydrocarbon＇s decreases;the content of CO2 of argillaceous dolomite is less than that of mudstone,and the contents of other gaseous components are opposite;with the rise of simulation temperature,gas product yields gradually increase,and the temperature corresponding to the oil generation peak is 330 ℃-350 ℃,which is lower than the temperature simulated by dry thermalsimulation and is closer to the geological condition;more carbonate in hydrocarbon source rock is advantageous to oil generation;CO2is generated mainly by thermal degradation of organic matter and a little by thermal cracking of carbonate in experimental conditions;carbon isotope compositions of gaseous hydrocarbons have lower variation extent and show the features of sapropel type gas;the main peak carbon number and relative content of high carbon number hydrocarbon for n-alkanes in expelled oil and residual oil decrease with the simulation temperature increasing;the biomarker parameters for expelled oil and residual oil have certain change,which should be taken into consideration in oil-source contrast application.
出处
《地球科学与环境学报》
CAS
2016年第1期93-103,共11页
Journal of Earth Sciences and Environment
基金
国家科技重大专项项目(2011ZX05001)
中国石油第四次油气资源评价项目(2013E)
关键词
泥质白云岩
泥岩
气态产物
液态产物
热模拟
排出油
风城组
玛湖凹陷
argillaceous dolomite
mudstone
gaseous product
liquid product
thermal simulation
expelled oil
Fengcheng Formation
Mahu sag
