准噶尔盆地春风油田浅薄储集层地震逐级精细预测

Stepped and detailed seismic prediction of shallow-thin reservoirs in Chunfeng oilfield of Junggar Basin, NW China

针对准噶尔盆地春风油田浅薄储集层地震资料信噪比低和分辨率不足等问题,开展针对性的处理、解释技术研究,形成浅薄储集层地震逐级精细预测方法。采用互叠式偏移距分组处理技术,将地震资料的覆盖次数由8次增加至16次,同时经过提频去噪成像等精细处理,局部低信噪比区信噪比提高1.4倍;建立叠前提高分辨率目标处理、叠后子波重构拓频、叠前叠后联合反演的三级预测技术,最终砂体分辨能力由12 m逐步提高至2 m,有效提高了储集层识别精度。浅薄储集层在逐级提频后的资料中反射更为清晰、连续,与实际钻探结果吻合较好,资料具有较好的保幅性,取得了较好的实际应用效果。

In view of the problems of low signal-to-noise ratio and low resolution of seismic data in shallow-thin reservoir in Chunfeng Oil field of Junggar Basin, stepped and detailed data processing and interpretation technologies are proposed for shallow-thin reservoir prediction. The overlapping type offset packet processing technology can increase seismic fold from 8 to 16 times and increase signal to noise ratio by 1.4 times at local low noise ratio area by fine processing including frequency upgrade and de-noise imaging techniques. This study established three-level prediction techniques including pre-stack improving resolution target processing, post-stack wavelet reconstruction frequency extension, pre-stack and post-stack joint inversion, which can increase sand resolution from 12 m to 2 m and improve the identification accuracy of reservoir efficiently. The shallow-thin reservoirs after frequency extension have continuous and defined reflections, which are well coincided with actual exploration. The seismic data have well ability of preserving amplitude, and achieve good application effects.