Distribution of volcanic reservoirs is controlled by various factors such as volcanic edifice, lithology and lithofacies and is difficult to be precisely predicted because of their complexity and heterogeneity. Volcanic reservoirs of crater-near crater sedimentary microfacies are the most favorable reservoirs and their seismic responses are characterized by chaotic high-frequency,discontinuous and irregular reflection configuration,rapid facies change and dome reflections. It is difficult to precisely characterize the volcanic reservoirs through seismic interpretation due to the limitation of seismic data quality. In the paper, we present a new seismic interpretation workflow based on the technique of three-dimensional seismic voxel and imaging analysis. First,structurally-oriented noise filter technique is used to improve the signaloise ratio of post-stack amplitude data. Then, volumetric seismic attributes including chaos and structurally-oriented discontinuity are used to identify volcanic reservoirs. Finally, three-dimensional imaging techniques with high resolution including attribute classfication automatic geobody detection and 3D visualization are applied to predict the spatial distribution of the volcanic reservoirs. This workflow is applied in Yingcheng Formation volcanic reservoir characterization in Fengle area, Xujiaweizi fault depression, northern Songliao basin. The reservoirs are clearly imaged and mapped, providing instructive constraints for further physical properties prediction of the volcanic reservoirs.%火山岩储集体分布受火山机构、岩性、岩相等控制,复杂多变,准确预测和刻画十分困难.火山口-近火山口微相沉积体是最有利的火山岩储集体,该类相储集体通常具有高频杂乱无序、反射断续无规律、相变快、穹窿状或丘状外形等地震响应特征,地震解释手段易受地震资料品质的影响而无法精确描述储集体特征.针对此问题,基于三维成像分析技术,提出了一套有利火山岩储集体地震识别刻画的技术流程.首先采用构造方位约束滤波技术对叠后振幅数据去噪处理,然后利用包括混沌属性、方位约束不连续性属性等三维地震属性识别储集体,进而采用三维属性聚类成像、像素体检测技术及三维可视化技术对目标储集体进行三维成像分析,获取该类储集体空间分布认识.将该流程应用到松辽盆地北部徐家围子断陷丰乐地区,对营城组火山岩储层进行识别预测.结果表明,营城组火山岩有利储集体得到了良好成像,储集体平面分布趋势和三维影像都很清晰,为储层物性预测提供了宏观依据.
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