非线性反演方法在剩余静校正中的应用

估算剩余静校正量本质上是一个非线性反演问题。当地震资料的剩余静校正量大、信噪比低时,利用线性反演方法不能有效地拾取静校正量。文中分别采用最大能量法和模拟退火法两种非线性的反演方法来估算炮点和检波点的剩余静校正量。这两种方法是将负叠加能量作为目标函数,静校正量作为模型参数。估算最佳的剩余静校正量需要确定多维目标函数的全局极小值。最大能量法的结果受初始静校正量的影响,它的解容易陷入目标函数的局部极小值。模拟退火法不受初值的影响,可以求得目标函数的全局极小值或其近似值。

Application of nonlinear inversion to residual static correction.

The estimation of residual static correction values is essentially a nonlinear inverse problem.The use of linear inversion fails to correctly pick up static cor- rection values when residual static correction values are high and S/N ratio is low.We use two nonlinear inversion methods(the maximum energy method and the simulated annealing method)to estimate the residual static correction values of source points and receiver points.These two methods use negative stacked energy as objective function and static correction value as model param- eter.The estimation of optimum residual static correction values requires locat- ing the global minimum of a multi-dimensional objective function.The result of maximum energy method depends on the initial values of residual statics.The solution is often trapped into the local minimum of the objective function.The simulated annealing method is independent of initial value and can usually find the solution which corresponds to the global minimum or the approximate val- ue.