海洋三维地震资料处理中的静校正方法

Static correction for 3D marine seismic processing

（CGGVeritas公司，美国得克萨斯休斯敦TX 77072）

CGGVeritas, Houston, TX 77072, USA

在海上油气勘探中，三维地震资料的采集通常会持续半年甚至一年。在如此长的时间中，海洋的物理条件，如水温、含盐度等都会发生很大的变化，而这些变化会改变地震波的传播速度。因此，在相同位置不同时间采集的地震资料会有不同的旅行时，从而产生了静校正问题。在三维地震资料处理中，这是一个长期存在而未解决的问题，为此提出了解决方法。该方法包括相邻测线段相对时差自动拾取和全局非线性反演，并在反演中引入先验知识加以约束。另外通过引入混合的l¹和l²范数使反演对相对大的残差不敏感，以消除自动拾取产生的误差。数值模拟和实际资料处理结果证明了方法的有效性。

In offshore exploration activities, 3D seismic data acquisition always lasts for half to one year. During this long period, the offshore physical conditions have big changes, including water temperature and saline concentration, making the propagation velocity of seismic wave change. Therefore, the seismic data acquired at the same position but in different time has different travel time, giving rise to the static correction problem. In 3D seismic data processing, the problem exists for a long time and cannot be solved. So we have developed a novel procedure to solve the problem. The procedure consists of automatic pick of the relative static shift between the sail lines and the global nonlinear inversion. Meanwhile, some prior knowledge is inducted in the inversion as constraints. Furthermore, the mixed l1 and l2 norm is used to make the inversion insensitive to large residuals, which can remove the error from automatic pick.Numerical simulation and actual date processing results show the method is effective.