进行翻译：计算梯度时依然可以基于声学假设。因为梯度大小只取决于反传的残差源中波形扰动的大小波场的幅值此时是系数项对计算结果的影响可以被迭代步长所矫正。

When calculating gradients, acoustic assumptions can still be based on. This is because the gradient magnitude depends only on the size of waveform perturbations in the backpropagated residual source, with the amplitude of the wavefield being a coefficient whose impact on the calculation can be corrected by the iteration step size.