Patent ID: 7447114

Claim:
A method of filtering seismic data, the method comprising: calculating, from an input seismic trace comprising negative and positive samples, a nonlinear compression trace using a plurality of the positive samples from the input seismic trace; calculating a nonlinear rarefaction trace using a plurality of the negative samples from the input seismic trace; and deriving a multi-component matching filter to fit a plurality of samples from the input seismic trace, nonlinear compression trace, and nonlinear rarefaction trace to a reference trace, wherein calculating a nonlinear compression trace using a plurality of the positive samples from the input seismic trace comprises selecting the positive samples S i >0 from the input seismic trace, and calculating a nonlinear compression sample Q i =ƒ(S i ) for each positive sample, wherein ƒ(x) is a nonlinear function, and wherein calculating a nonlinear rarefaction trace using a plurality of the negative samples from the input seismic trace comprises selecting the negative samples S i <0 from the input seismic trace, and calculating a nonlinear rarefaction sample Z(i)=ƒ(S i ) for each negative sample, and wherein deriving a multi-component matching filter comprises minimizing the function V = ∑ i = 1 N ⁢ ( R i - ∑ j = - L M ⁢ F ⁢ ⁢ 1 j * S i + j - ∑ j = - L M ⁢ F ⁢ ⁢ 2 j * Q i + j - ∑ j = - L M ⁢ F ⁢ ⁢ 3 j * Z i + j ) 2 , wherein the multi-component matching filter comprises an adjusted normal trace filter F 1 , a compression filter F 2 , and a rarefaction filter F 3 .