Study And Application Of Denoising Techniques On Marine Multi-streamer Seismic Data

As the improving of world economy and technology, the demand for oil isgrowing. Concerning the severer energy situation in the world, oil exploration alsofaces increasing challenge. With the shrinking of land seismic exploration, marineseismic exploration has become more and more important. In recent years, morethan half of the oil and gas of the world are discovered in the ocean, especially in thedeep sea. Deepwater oil and gas exploration has become the most important field ofthe global oil and gas exploration. Multi-streamer seismic exploration has lots ofadvantages, such as great exploration depth, high exploration efficiency and highsignal-to-noise ratio etc. In particular, this method plays an important role in deepsea seismic exploration. Noise of multi-streamer seismic data has its owncharacteristics under the complex ocean environment. Through the multi-cableseismic acquisition, we study the noise characteristics and develop typical noisesuppression method in detail, which has far-reaching significance for futureabysmal-sea oil and gas exploration.This article conducts a brief description of multi-streamer seismic explorationin those aspects of the exploration pattern, construction design and quality control.The paper elaborates the various types, characteristics, causes and the degree ofnoise interference in data acquisition, and by studying intensively about the noisecharacteristics, noise suppression in the data acquisition has been applied effectively.In the later data processing, we find the optimal algorithm for differentcharacteristics for effective noise suppression through in-depth research in differentmathematical domains of the noise and significant wave characteristics.Swell noise, linear noise and abnormal amplitude are the most common noisein multi-cable seismic exploration. These noises are strong enough to affect effectivewave severely. Based on the research of the actual data, we know that there may beinterference between cables, also seismic data for multiple cables contribute to betterstatistical characteristics of common noise of the single cable. The frequency-wavenumber domain transform is good at suppressing the strong linearnoise in multi-streamer seismic data, and time frequency analysis method applied forswell noise and abnormal amplitude can remove the noise efficiently, and protectvalid information well.How to accurately identify and effectively suppress multiple waves has been along-term challenge in marine seismic exploration. Multiple waves seriously affectsmarine multi-streamer seismic data, and interferences the energy of effective waveseverely, which reduces the signal-to-noise ratio and the data resolution, and alsobrings great difficulties to the subsequent velocity analysis, migration imaging andgeological interpretation. In this article, we eliminate the multiple waves usinganisotropic Radon transform and SRME methods for marine multi-streamer seismicdata. Anisotropic Radon transform has a good result for deep water and large offsetmultiple waves, while SRME method is effective for near offset multiple waves. Inthe end, jointly taking the advantages of these two methods, we propose a newmethod to suppress multiple waves combining anisotropic Radon transform andSRME method, so that a good processing result is obtained and the signal-to-noiseratio of data is improved greatly.In this paper, using an optimal method to suppress swell noise, abnormalamplitude, linear noise and multiple wave based on the study of various denoisingtheory, we process denoising for a typical real multi-streamer seismic data of acertain area, and achieve satisfactory denoising effect, greatly improve the resolutionof data, which laids the foundation for subsequent high-resolution seismic dataimaging and geological interpretation.