Geophysics-informed neural network for model-based seismic inversion using surrogate point spread functions

Abstract

Model-based seismic inversion is a key technique in reservoir characterization, but traditional methods face significant limitations, such as relying on 1D average stationary wavelets and assuming an unrealistic lateral resolution. To address these challenges, we propose a Geophysics-Informed Neural Network (GINN) that integrates deep learning with seismic modeling. This novel approach employs a Deep Convolutional Neural Network (DCNN) to simultaneously estimate Point Spread Functions (PSFs) and acoustic impedance (IP). PSFs are divided into zero-phase and residual components to ensure geophysical consistency and to capture fine details. We used synthetic data from the SEAM Phase I Earth Model to train the GINN for 100 epochs (approximately 20 minutes) using a 2D UNet architecture. The network's inputs include positional features and a low-frequency impedance (LF-IP) model. A self-supervised loss function combining Mean Squared Error (MSE) and Structural Similarity Index Measure (SSIM) was employed to ensure accurate results. The GINN demonstrated its ability to generate high-resolution IP and realistic PSFs, aligning with expected geological features. Unlike traditional 1D wavelets, the GINN produces PSFs with limited lateral resolution, reducing noise and improving accuracy. Future work will aim to refine the training process and validate the methodology with real seismic data.