准噶尔盆地滴西地区火成岩岩性识别方法研究

Igneous Rock Lithologic Identification in Dixi Area of Jungger Basin

火成岩岩性识别是火成岩油气藏储层评价的基础。以准噶尔盆地滴西地区的火成岩岩性识别为例,应用对应分析的方法发现自然伽马(GR)测井曲线对火成岩岩性最敏感,其次为补偿中子(CNL)。由于常规测井在凝灰岩、火山角砾岩与其他火成岩岩性的区分上难度较大,因此制定了"成像测井识别岩性结构、常规测井识别岩石成分"的多层次综合识别方法。该方法在实际资料的处理中取得了很好的应用效果,岩性综合识别结果与岩心薄片鉴定的结论基本符合,解释符合率平均达到90%以上,其中误识的岩性主要为凝灰岩和火山角砾岩,另外安山质玄武岩与闪长玢岩的岩石成分比较相近,识别过程中也容易出现误差。

It was essential to identify the lithology of igneous rocks in reservoir evaluation.The identification of igneous rock lithology of Dixi Area of Junggar Basin was taken for example.It was found out by the analysis with corresponding method that GR logging curve was sensitive to igneous rock lithology,CNL was next.Because it was difficult to identify the lithology of tuff,volcanic breccia and the other igneous rocks in conventional logging.According to the analysis,the method of lithologic identification,which was to identify lithologic structure by using FMI and to identify the rock composition by using conventional logging,was developed,and its coincidence rate was 90% comparing with the thin section analysis.The volcanic tuff and volcanic breccia are more difficult to be recognized and have a higher error than the other igneous rocks',and mistake is easy to be made in identification.