摘要
高分辨率地震反演面临着:①地震反演是一个不适定问题,存在多解性;②采集和处理流程产生噪声和畸变降低反演算法的稳定性,针对这两个问题,提出一种基于L_1-L_1范数稀疏表示的地震反射系数反演方法。该方法利用L_1范数正则化项降低反演多解性和L_1范数拟合项增加噪声鲁棒性。通过井震联合提取子波构建过完备楔形子波字典,然后用L_1-L_1范数稀疏表示对地震信号进行稀疏分解,实现高分辨率反射系数反演。楔形模型和实际地震资料试算结果表明,该反演算法稳定,具有良好的噪声鲁棒性,通过测井资料标定检验,其反演结果准确可信。
High-resolution seismic inversion is confronted with two problems: First,seismic inversion is an ill-posed problem and has multiplicity of solutions,and second,noise and distortion are generated in the flows of acquisition and processing to reduce the stability of the inversion algorithm.Aimed at solving these two problems,this paper proposes an inversion method of seismic reflectivity based on L_1-L_1-norm sparse representation.Firstly,the L_1-norm regularization term is used to reduce the inversion multiplicity,and then the L_1-norm fitting term is used to enhance the noise robustness.The wavelet is extracted by well logging and seismic data to construct the over-complete wedge wavelet dictionary,and then the seismic signal is sparsely decomposed by the L_1-L_1-norm sparse representation,so as to realize the high-resolution reflectivity inversion.The experimental results of wedge model and actual seismic data show that the inversion algorithm is stable and has good noise robustness,and the inversion results are accurate and credible through logging data calibration.
引文
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