Time reversal is a key component of time-reverse migration and source location using wavefield extrapolation. The implementation of time reversal depends on the time symmetry of wave equations in acoustic and elastic media. This symmetry in time is no longer valid in attenuative medium. Not only the velocity is anisotropic in shale oil and gas reservoirs, but also the attenuation is usually anisotropic, which can be characterized by viscoelastic orthotropic media. In this paper, the fractional order viscoelastic anisotropic wave equation is used to decouple the energy dissipation and the velocity dispersion. By changing the sign of the dissipation term during backpropagation, the anisotropic attenuation is compensated and the time symmetry is restored. The attenuation compensation time-reverse location algorithm can effectively locate the source in viscoelastic orthotropic media. Compared to cases without attenuation compensation or using isotropic attenuation compensation, this method can remove location error caused by anisotropic attenuation and improve the imaging effect of the source. This paper verifies the effectiveness of the method through theoretical analysis and model testing.

时间逆转是使用波场外推法进行时间逆向偏移和震源定位的关键组成部分。时间逆转的实现取决于声学和弹性介质中波动方程的时间对称性。时间上的这种对称性在衰减介质中不再有效。页岩油气储层中的速度不仅是各向异性的，而且衰减通常是各向异性的，这可以通过粘弹性正交各向异性介质来表征。本文采用分数阶粘弹性各向异性波动方程解耦了能量耗散和速度色散。通过在反向传播期间更改耗散项的符号，可以补偿各向异性衰减并恢复时间对称性。衰减补偿时间逆向定位算法可以有效地将源定位在粘弹性正交各向异性介质中。与没有衰减补偿或使用各向同性衰减补偿的情况相比，该方法可以消除由各向异性衰减引起的位置误差，并提高源的成像效果。本文通过理论分析和模型测试验证了该方法的有效性。