变系数ΔLgR烃源岩测井评价技术关键参数厘定方法及应用  

Predicting Key Parameters for Variable-CoefficientΔLgR Logging Technique and Its Application in Source Rocks Evaluation

作　　者：刘超[1] 印长海[1] 卢双舫[2] 

机构地区：[1]大庆油田有限责任公司勘探开发研究院,黑龙江大庆163712 [2]中国石油大学(华东)非常规油气研究院,山东青岛266580

出　　处：《天然气地球科学》2015年第10期1925-1931,共7页Natural Gas Geoscience

基　　金：国家自然科学基金(编号:41172134);国家自然科学重点基金(编号:41330313)联合资助

摘　　要：针对当前变系数ΔLgR烃源岩测井评价技术的关键参数主要通过经验确定,存在缺乏客观性、定量预测方法不足等问题,研究该技术内关键系数(k和a)的'外推性',建立利用单井资料预测关键系数的方法。基于松辽盆地白垩系主要烃源岩层的测井和TOC分析数据,通过对比关键系数在稳定沉积地层和断陷复杂地层的外推效果发现,后者导致的TOC误差偏大,有必要研究针对单井的k值和a值的预测方法。建立了利用单井'声波时差—电阻率'交会预测k值的方法,预测结果的可信度可达到81%以上;建立了利用烃源岩厚度、成熟度和幅度差值计算系数a的公式,预测结果的可信度超过80%。该方法对沉积稳定地层和复杂地层都适用,可比目前外推方法误差降低10%以上。For the present,key parameters in Variable-coefficient △LgR logging technique are estimated by experience,lacking of quantitative predicting method. To solve this problem, extrapolation effects of the key parameters （k and a） in this technique were studied,and practical methods for calculating key parame- ters using single well data were brought forward. Based on the TOC and well logging curves of Cretaceous stratus in the Songliao Basin,it is found that calculation of TOC value using other wells＇ key parameters cannot always get satisfied results, especially in the complex strata in which TOC errors often became so great that it is necessary to calculate the key parameters according to single well. Practical methods for pre- dicting key parameters were established,＂k＂ was predicted form the slope of interval transit time versus re- sistivity,the predicting error is less than 19%;＂a＂ was calculated from the averaged value of shale thick- ness,Ro and △LgR, with the predicting error is less than 20%. Methods in this paper are suitable for both stable and complex formations,but more effective and necessary for complex formations,and TOC predic- tion errors can be reduced over 10% compared with traditional method. Methods in this paper provided a foothold for the further application of Variable-coefficient △LgR technology in TOC evaluation of source rock, especially in complex formations.

关 键 词：有机碳总量 变系数 ΔLgR 测井 烃源岩 松辽盆地 

分 类 号：P618.13[天文地球—矿床学]