致密气藏烃源岩地化参数测井综合评价方法研究

针对塔里木盆地库车坳陷北部侏罗系烃源岩受泥浆污染、分析数据少、样品分布不连续及类型多样等问题突出,利用测井资料来对有机地球化学参数进行评价难度大,无法满足勘探需求.本文阐述了不同类型烃源岩的有机质级别、测井响应特征、有机地球化学参数定量计算及品质评价等多种方法,来研究富集区烃源岩对致密气储层的持续供气能力.文中介绍了煤层、碳质泥岩、暗色泥岩等3种类型烃源岩的有机质级别和测井响应特征.首先,提出分不同岩性烃源岩的ΔlogR法,其计算结果与铀曲线相关法、多元回归法对比,效果最好;再次建立了生烃潜率、氯仿沥青“A”及镜质体发射率等多个有机质地球化学参数的测井评价模型;最终,考虑能够反映烃源岩性质的参数来综合定义烃源岩品质指数,形成了完善的烃源岩测井综合评价方法研究技术.研究表明,利用这套地球物理技术提供了烃源岩定量评价和品质分类研究方法及实际应用案例.

Well logging evaluation method research of source rock geochemical parameters in the tight gas

The Jurassic source rocks at the northern region of Kuche depression in Tarim Basin are affected by mud,less core analysis data,discontinuous sample distribution,various types and other problems.Based on these,it is difficult to comprehensively evaluate the organic geochemical parameters using logging data,which cannot meet the needs of exploration.To study the continuous gas supply capacity of hydrocarbon source rocks to tight gas reservoirs in the enrichment region,this paper describes the organic matter grade,log response characteristics,geochemical parameter quantitative calculation,quality comprehensive evaluation and other methods of different types of source rocks.The paper introduced the organic matter grade and log response characteristics of three types of source rocks,including coal seams,carbonaceous mudstones and dark mudstones.First,TheΔlogR method for different lithology of source rocks is proposed,and its calculation results are the best compared with uranium curve correlation method and multiple regression method.Then,it establishes the logging evaluation models for multiple organic texture parameters with hydrocarbon generation potential,chloroform asphalt“A”and vitrinite emissivity.Finally,considered the geochemical parameters that can reflect the properties of source rocks,the source rock quality index is comprehensively defined,and formed a set of well logging comprehensive evaluation method and research technology of source rock.The studies have shown that the set of geophysical techniques provides these research methods for quantitative evaluation and quality classification of source rocks,and practical application cases.