Objective Logging-while-drilling electrical resistivity imaging (LWD-ERI) enables the intuitive presentation of geobodies near wellbores in images, representing an important approach to the fine-scale evaluation of stratigraphic parameters while also providing significant geological guidance during the drilling of fractured reservoirs. However, this technique faces the challenge of low image resolution in real-time data processing due to its limited well-to-surface data transmission rates, exerting adverse impacts on the qualitative identification of wellbore fractures and the quantitative evaluation of their parameters. To address this issue, this study proposed a super-resolution image reconstruction method based on a generative adversarial network (GAN), aiming to achieve high-definition fracture images.

Methods Based on the basic GAN architecture, a 23-layer deep generator network was constructed by integrating the GAN with residual dense blocks (RDBs) and channel attention mechanism (CAM). Meanwhile, a dataset consisting of high-resolution images stored and low-resolution real-time images was constructed using measured data from a resistivity-at-bit (RAB) tool. Subsequently, through training of the GAN using the constructed image dataset, the batch size and learning rate were optimized. Accordingly, the network parameters corresponding to smaller errors and higher precision were determined. Finally, the trained network model was utilized for the super-resolution image reconstruction of real-time data to achieve an image resolution close to that of the stored data.

Results and Conclusions  Compared to traditional methods, the proposed super-resolution image reconstruction method improved the peak signal-to-noise ratio (PSNR) and structural similarity (SSIM) index by 2.2 dB and 0.6, respectively. Under 4× downsampling, the intelligent method remained effective in reconstructing the image features of fractured geobodies, significantly enhancing the resolution of real-time LWD images. The results of this study hold great significance for enhancing the real-time geological guidance during drilling operations.