Migration velocity analysis is one of the key steps in pre stack depth migration whose accuracy directly affects the quality of pre stack depth migration.

偏移速度分析是叠前深度偏移的关键步骤之一，它的准确与否直接影响叠前深度偏移的质量。

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But to layered strata, the seismic wave path is complicated when reservoir changes, and it is difficult to directly define vertical time difference by pre stack far offset seismic data.

对于层状介质，油藏变化前后的地震波传播路经比较复杂，其激发点和接受点发生了变化，要想用叠前远偏移距数据直接计算垂直时差比较困难。

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Pre stack depth migration which starts directly from undulating earth surface turns out to be a valid way to deal with irregular topography and complex geologic structures.

直接从起伏地表开始的叠前深度偏移方法是对付复杂地表和复杂地质构造成像的有效手段。

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The QNX CAR application platform from QNX Software Systems is a comprehensive, pre-integrated software stack designed to help automotive companies reduce the time and effort of building highly sophisticated and connected infotainment systems.

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