单程波叠前深度偏移中的界面深度问题研究

Study of reflective layer depth in one-way pre-stack depth migration

单程波深度偏移计算中,两条主要因素影响到反射层的正确定位,一是算子带来的子波相位变化,二是炮点子波脉冲延迟.本文首先r推导了单程波算子导致的相位变化,并且介绍了一种比水平反射层模型偏移验证方法更简单的脉冲叠加验证方法,并用该方法用脉冲试验对比了单程波偏移相位的变化和改正后的结果,子波延迟导致的反射层深度的变化和改正后结果,最后应用三维SEG/EAGE模型进行测试,结果表明两种情况改正后的剖面反射层位置准确.

For one-way pre-stack depth migration ,there are two factors that affect the refleclive layer depth： one is the one way depth migration operator ,it can change the phase characteristic, the second is the pulse lime delay as the shot wave field. In this paper , we first prove theoretically pre stack one way depth migration will change the phase characteristic, and provide a simple method with stacking the pulse migration result. By using this method , we test the changed phase characteristic and the result after correction, the reflective layer depth change caused hy the delay time of pulse and the result after the change. At last we demonstrate our two correction methods with the 3D SEG/EAEG model.