Abstract: The volcanic rocks of the Yingcheng formation in the Songliao Basin were formed by multiple and intermittent eruptions. Based on the core drilling data, the high-resolution volcanic cycles of the first member of Yingcheng formation in Xujiaweizi fault depression were divided, the volcanic cycle model were built, and the well logging characteristics of different lithology and lithofacies were summarized. The results reveal that, the first member of Yingcheng formation could be divided into 3 volcanic cycles, from the top to the bottom of each cycle, the values of gamma-ray and resistivity were higher and higher, the amplitude and frequency of the well logs in the interface of different cycles changed greatly, indicating the existence of the weathering crust or the sedimentary layer. Logging data of gamma-ray, resistivity and density were considered to be more sensitive in recognition of different volcanic lithology and lithofacies.

Key words: Songliao basin, Xujiaweizi fault depression, volcanic cycles, logging characteristics of volcanic rocks

摘要： 在钻井取芯研究的基础上，应用测井资料，开展了松辽盆地北部徐家围子断陷营城组营一段高分辨火山岩旋回的划分，建立了营一段火山岩的旋回模式，并总结了营城组一段不同岩性、岩相的测井响应特征。研究结果表明，营一段划分为3个旋回，每个火山岩旋回的自然伽马和电阻率曲线值在底部一般为中高值，顶部为低值；在不同旋回界面，测井曲线振幅和变化频率明显增大，指示风化壳或沉积夹层等标志性界面的存在；并通过研究认为自然伽马、电阻率和密度3种测井曲线对火山岩岩性和岩相识别最为敏感。

关键词: 松辽盆地, 徐家围子断陷, 火山岩旋回, 火山岩测井特征