【摘要】 采集参数和观测系统设计是资料采集质量的根本保证,为此,对轮古38井三维VSP数据采集方法进行了探讨。首先以轮古38井区已有资料为基础,结合三维VSP所要解决的地质问题,建立了地质模型;然后利用射线追踪、波动方程正演模拟等方法对观测方式进行了分析论证,确定了最大偏移距、检波器的沉降深度、接收点距、震源位置和炮点间距等采集参数,探讨了这些参数对地下成像范围和覆盖次数的影响;最后利用成像范围、面元大小、覆盖次数、入射角等参数对设计的观测系统作了进一步论证评价,确定了最佳的三维VSP采集施工方案。轮古38井的应用实例表明,利用所设计的三维VSP观测系统获得的资料,信噪比和分辨率都要优于三维地面地震资料,成像更清晰。更多还原

【Abstract】 Acquisition parameters and geometry design are crucial to the quality of acquisition data. Based on original data, a geologic model is constructed according to the geologic tasks of 3-D VSP survey for Lungu 38 well. Analyzing the survey method by ray tracing and wave equation forward modeling, we determined the acquisition parameters such as the maximum offset, receiver depth, receiver space, shot station and shot space, etc. The optimal 3-D VSP acquisition scheme was formed after further evaluation on bin size, fold and incidence angle. The result of 3-D-VSP survey for Lungu 38 Well shows that the acquisition data has higher S/N ratio and resolution than those of routine 3D seismic data.更多还原