Multiple self-adaptive subtraction based on dip decomposition

The self-adaptive subtraction is an important procedure of multiple-attenuation by wave-equation prediction subtraction method. With the common L2-norm self-adaptive subtraction algorithm based on minimum energy, when matching, the derived filter operator will damage primary energy if multiples and primaries overlap; therefore, the primary energy will be damaged in subtraction. We proposed a new method that combined Tau-p transform and L2-norm self-adaptive subtraction. Firstly, Tau-p transform is used for dip-decomposition of seismic shot gathers to separate the primaries and multiples in the overlapped area. Secondly, the self-adaptive subtraction is carried out on the data after dip decomposition. Thirdly, the subtraction results are combined as output, which may reduce and even avoid the damage to primaries. Synthetic and actual data testing verified the validity of the method.