Seismic full waveform inversion (FWI) is a powerful geophysical imaging technique that produces high-resolution subsurface models by iteratively minimizing the misfit between the simulated and observed seismograms. Unfortunately, conventional FWI with least-squares function suffers from many drawbacks such as the local-minima problem and computation of explicit gradient. It is particularly challenging with the contaminated measurements or poor starting models. Recent works relying on partial differential equations and neural networks show promising performance for two-dimensional FWI. Inspired by the competitive learning of generative adversarial networks, we proposed an unsupervised learning paradigm that integrates wave equation with a discriminate network to accurately estimate the physically consistent models in a distribution sense. Our framework needs no labelled training data nor pretraining of the network, is flexible to achieve multi-parameters inversion with minimal user interaction. The proposed method faithfully recovers the well-known synthetic models that outperforms the classical algorithms. Furthermore, our work paves the way to sidestep the local-minima issue via reducing the sensitivity to initial models and noise.
翻译:地震完全波形反转(FWI)是一种强大的地球物理成像技术,它通过迭代地尽量减少模拟和观测到的地震图之间的误差,产生高分辨率的地表下模型。 不幸的是,传统的最小方形功能FWI有许多缺点,如局部-minima问题和计算显性梯度等。这在受污染的测量或原始模型方面尤其具有挑战性。最近依靠局部差异方程和神经网络的工程显示了二维FWI的有希望的性能。在基因对抗网络竞争性学习的启发下,我们提出了一个未经监督的学习模式,将波方程式与歧视性网络相结合,以准确估计分布意义上的物理一致性模型。我们的框架不需要有标签的培训数据或网络的预培训,而是灵活地实现多参数的转换,同时最小的用户互动。拟议方法忠实地恢复了远高于经典算法的众所周知的合成模型。此外,我们的工作为通过降低对初始模型和噪音的敏感度而绕过本地-未成年人问题铺平铺平了道路。