Seismic Acoustic Impedance Inversion Using Reweighted L1-Norm Sparse Constraint

Sparse impedance inversion is widely applied for hydrocarbon prediction. Due to the low sparseness of traditional sparse constraints, pseudolayer and low-resolution problems still exist. To overcome this barrier, an impedance inversion method based on the reweighted L1-norm sparse constraint is proposed. Different from the traditional L1-norm constraint, which considers the location information of impedance boundaries, the reweighted L1-norm uses the amplitude information of impedance boundaries. The amplitude information can improve the sparseness, which helps inversion obtain more precise boundaries of impedance and weaken the pseudolayer phenomenon. Both the reweighted L1-norm constraint and initial model constraint are used to construct the objective function. The alternating direction method of multipliers (ADMM) algorithm is utilized to obtain the inversion algorithm. Both synthetic and field data tests prove that the impedance boundary of the proposed method is more accurate, and the pseudolayer phenomenon is weakened.