对准噶尔盆地腹部地区地震成像的地震速度影响分析

在准噶尔盆地腹部夏盐3井区存在时间域与构造域高低幅度差异大的问题。基于存在的问题·前期研究对该地区进行三维叠后重新处理和利用三维速度建模变速构造成图，为夏盐5井的钻探提供了决策依据。钻探后发现。夏盐5井构造高点并不存在，造成这些现象的原因是该地区构造复杂、地震速度横向变化大，常规叠后时间偏移不能使反射波正确归位，需要使用三维叠前深度偏移技术才能实现复杂目标区的高精度成像。研究指出速度建模是关键，并给出了相应的速度建模对策。解决了该地区构造深度与地震双程时间不一致的矛盾。为随后钻探的井提供了地质依据。

Effect of Seismic Velocity of Seismic Imaging in the Center of Junggar Basin

There existed a problem of big difference from high extent to low extent on time domain and tectonic domain in Well Xianyan 3. Based this problem, after the pre-research was carried on 3D poststack processing and a three-dimensional velocity model was used to build a variable velocity structure map, by which bases was provided for drilling the Well Xianyan 3 . After drilling, it was found that structural height of Well Xianyan 3 was not existed. The reason was that the structure was complicated, lateral cha...