(1. 成都理工大學(xué) 地球物理學(xué)院,成都 610059;2. 中國(guó)石化勘探南方分公司,成都 610041)
摘 要: 為提高地震波阻抗反演的分辨率及運(yùn)算效率,提出一種邊界保持塊約束的疊后波阻抗反演方法。首先,根據(jù)反射系數(shù)的稀疏特性,并利用正則化技術(shù),避免反演過(guò)程的平滑效應(yīng)構(gòu)造出波阻抗塊約束反演的目標(biāo)函數(shù);其次,推導(dǎo)出用對(duì)數(shù)波阻抗差值代替反射系數(shù)的邊界保持的塊約束反演系統(tǒng)方程;再次,推導(dǎo)出對(duì)應(yīng)反演系統(tǒng)方程的共軛梯度算法和關(guān)鍵的向量計(jì)算公式。結(jié)果表明:反演波阻抗呈明顯分塊特征,上下巖層界線明顯,分辨率高,說(shuō)明反演方法可靠,該方法具有邊界保持、分辨率高、收斂速度快、精度高的特點(diǎn),實(shí)現(xiàn)簡(jiǎn)單、高效。
關(guān)鍵字: 邊界保持;塊約束;波阻抗反演;共軛梯度算法
(1. College of Geophysics, Chengdu University of Technology, Chengdu 610059, China;
2. SINOPEC Exploration Southern Company, Chengdu 610041, China)
Abstract:To improve the resolution of seismic impedance inversion and computational efficiency, a post-stack seismic inversion method based edge preserving blocky constrain was developed. First, according to the sparse characteristic of reflection coefficient, and using regularization technique, the objective function of seismic inversion was constructed to avoid smoothing effect; Secondly, equations of inversion system were deduced based on edge preserving blocky constrain and using the difference of logarithmic impedance in stabilizing the reflection coefficient; Additionally, the conjugate gradient algorithm was deduced, and the key vectors formulas were also derived. The results show that inverted seismic impedance has significant block feature, and the rock bottom line is clear, which indicates that the inversion method is reliable. The features of inversion method are edge preserving, high resolution, fast convergence, and high accuracy, simplicity and efficiency.
Key words: edge preserving; blocky constraining; seismic impedance inversion; conjugate gradient algorithm


