【摘要】 在准噶尔盆地南缘地区,应用叠前时间偏移技术和叠前深度偏移技术取得了明显的偏移效果。叠前时间偏移的速度分析是对CRP道集按一定间隔反复迭代修正,得到较准确的均方根速度场,可得到信噪比较高、偏移归位较准确的成像剖面。叠前深度偏移是基于模型的,摆脱了地下介质为水平层状及各向同性的假设条件,利用射线追踪原理进行偏移,在整个处理过程中,利用层析成像等技术不断优化深度-速度模型,直至该模型达到较高精度,获得了偏移归位准确、较真实反映地下构造形态的深度剖面。图5参3更多还原

【Abstract】 The pre-stack time migration and depth migration have been successfully used in the south margin of the Junggar Basin for the data processing. Velocity analysis in the pre-stack time migration could be used for buiding an accurate RMS velocity section after having updated velocity correction to CRP gathers for several times. Higher signal-to-noise ratio, move dipping reflectors into their true subsurface position, and collapse diffractions could be achieved. Pre-stack depth migration is model-based, which is migrated by theory of ray tracing, discarding the assumption of horizon, stratified medium and isotropy. In the data processing, the pre-stack depth migration updates depth-velocity model until it reaches high quality by using tomography image principle.更多还原