Abstract:Cross-block oil-water layer(OWL) identification is essential for petroleum development. Traditional methods are greatly affected by subjective factors due to depending mainly on the human experience. AI-based methods have promoted the development of OWL identification. However, because of the significant geological differences across blocks and the severe long-tailed distribution(class imbalanced), the identification effects of existing artificial intelligence(AI) models are limited. In this paper, we address this limitation by proposing a dynamic fusion-based federated learning(FL) for OWL identification. To overcome geological differences, we propose a dynamic weighted strategy to fuse models and train a general OWL identification model. In addition, an F1 score-based re-weighting scheme is designed and a novel loss function is derived theoretically to solve the data long-tailed problem. Further, a geological knowledge-based mask-attention mechanism is proposed to enhance model feature extraction. To our best knowledge, this is the first work to identify OWL using FL. We evaluate the proposed approach with an actual well logging dataset from the oil field and a public 3W dataset. Experimental results demonstrate that our approach significantly out-performs other AI methods.