叠前时间偏移成像处理技术在古龙断陷应用研究

古龙断陷位于松辽盆地西部断陷区,中浅层采集地震资料在深层反射能量弱、信噪比低,深层偏移距不够,造成深层成像困难,导致基底结构和地层分布特征认识不清,难以满足深层勘探。为此,我们开展了叠前时间偏移处理技术研究,本文在克希霍夫叠前时间偏移原理以及偏移速度模型精确建立方法的基础上,通过高密度自动速度分析、叠前时间偏移孔径试验及偏移距分组实验,讨论了影响叠前时间偏移成像效果的因素,选择合理的处理参数,对本区资料进行了处理。处理结果表明,与老剖面相比,新剖面深层的成像效果好。

The Application of Pre-stack Time Migration Imaging Processing Technology in Gulong Faulted Depression

Gulong faulted depression is located in the west faulted area of Songliao basin. The seismic data collected in the mid-shallow layer showed a weak signal-to-noise ratio, which caused the difficulty of deep imaging, leading to the failure of exploration of basement structure and strata distribution. Therefore, we conducted a research on the key technology in pre-stack time migration imaging under complicated deep geological conditions, based on Kirchhoff technology in pre-stack time migration and migration velocity model. We discussed the influencing factors of pre-stack time migration imaging, and selected reasonable processing parameters to analyze the data for this area by high density automatic speed analysis, pre-stack time migration aperture test, and the experiment of offset in groups. Results showed that the new deep profile imaging was better than old profile.