As the demand for nonrenewable oil and gas resources has increased, distributed acoustic sensing systems (DAS) have been widely used in the acquisition of vertical seismic profiles. Complicated subsurface conditions produce many types of noise with strong energy. The effective reflection and refraction signals are absorbed by the inelastic medium during the transmission process, resulting in significant energy loss and aliased frequency characteristics. However, satisfactory processing results and quality cannot be achieved through conventional denoising methods. In recent years, the rapid development of deep-learning methods with attention mechanisms has attracted significant attention. Noise reduction and signal reconstruction technologies with multiple attention mechanisms within the framework of joint-domain features have become important development directions in DAS data processing. An attention mechanism can help the network ignore useless information and pay attention to useful information in the same way that humans can. In this study, we discuss a novel learnable dual attention fusion network that combines local and patch-based nonlocal attention mechanisms based on ResBlock modules, making the extraction process of the network learnable and selective. In addition, the novel network can focus on local and global details. We also use a residual learning strategy to simplify the training process and gradually establish the best mapping based on the L2 loss function. All experimental results of the simulation and actual records show that our novel network has better denoising and effective signal restoration abilities. Moreover, it can recover the up-going and down-going wavefields and attenuate different types of noise with less effective energy loss.
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