单个油包裹体和微区沥青显微红外光谱分峰拟合技术及应用  

Curve-Fitting Analysis of Micro FT-IR and Its Application on Individual Oil Inclusion and Micro-Area Bitumens

作　　者：王倩茹[1] 陈红汉[1] 胡守志[1] 赵玉涛[2] 陈慧钦 

机构地区：[1]中国地质大学构造与油气资源教育部重点实验室,湖北武汉430074 [2]中国石油天然气股份有限公司吉林油田分公司勘探开发研究院,吉林松原138001

出　　处：《地球科学（中国地质大学学报）》2016年第11期1921-1934,共14页Earth Science-Journal of China University of Geosciences

基　　金：国家重点基础研究发展计划"973"项目(No.2012CB214804);中国地质大学(武汉)教学实验室开放基金项目(No.skj2014001)

摘　　要：针对单个油包裹体和储层沥青等结构复杂样品傅里叶变换显微红外光谱吸收峰严重重叠的问题,基于高斯、洛伦茨函数或其组合（高斯-洛伦茨）模型理论,采用显微红外分峰拟合技术,对塔中北坡顺托果勒地区单个油包裹体成熟度和储层沥青成因进行了系统分析,并取得了4点认识：（1）通过与Pironon对合成油包裹体的峰位坐标区域化划分吸收峰对比,认为分峰拟合技术更为真实地反映各子峰的面积,而且能够识别重叠区＂隐蔽＂的吸收峰,有助于准确判别有机质的结构组成;（2）高斯、洛伦茨函数或其组合（高斯-洛伦茨）模型拟合子峰时,高斯-洛伦茨函数分布拟合的吸收峰与实测光谱吻合度较高,噪音目标越低拟合效果越好,但计算耗时越长,故优选噪音目标在1-10高斯-洛伦茨函数分布拟合各子峰;（3）结合流体包裹体系统分析和均一温度-埋藏史投影法,单个油包裹体显微红外参数（CH2a/CH3a、Xinc、Xstd等）揭示塔中北坡顺托果勒地区存在3期油充注,分别为加里东晚期、晚海西期和喜山期;（4）显微红外光谱定量化分析是研究储层沥青多成因化和多期次油气充注叠加作用的有效手段,分析结果说明塔中北坡顺托果勒地区储层沥青经历了生物降解、氧化降解和水洗淋滤作用.Curve-fitting analysis of micro FT-IR,in the theory of Gaussian,Lorentz function or their combination （Gaussian-Lorentz）model,can break through the limit of overlapping spectra resulting from complicated structures of samples （e.g.indi-vidual oil inclusion and bitumens）.Hence,curve-fitting analysis of micro FT-IR was used for analyzing maturity of individual oil inclusion and the origin of bitumens in Shuntuoguole area of Tazhong northeastern slope systematically,and four conclusions have been obtained：firstly,curve-fitting analysis of micro FT-IR may be more accurate for calculating absorption peaks,and some easily neglected peaks can be detected by this method in contrast with the method of interval oriented by Pironon.Second-ly,Gaussian-Lorentz fitting is more approaching to actual spectra and the lower noise level is corresponding to better fit but re-quiring longer computation time.As a result,Gaussian-Lorentz fitting with 1-10 noise level is preferred.Thirdly,based on in-clusion system analysis and burial history projection with homogenization temperature,infrared parameters （e.g.CH2a/CH3a, Xinc and Xstd）reveal three hydrocarbon charging events occurred,including Late Caledonian,Late Hercynian and the Himala-ya.Finally,micro FT-IR is an effective means for analyzing multi-hydrocarbon charging events and complicated origin of bitu-mens undergoing biodegradation,oxidative degradation and water eluviation quantitatively in study area.

关 键 词：显微红外光谱 分峰拟合 单个油包裹体 微区沥青 志留系 塔里木盆地 石油地质 

分 类 号：P632[天文地球—地质矿产勘探]