Abstract:Presented here is a prestack noise suppression method which is applied to multiple NMO-corrected trace gathers.If traces in a gather are arranged in offset order,a vector Vx0(N) in N-dimensional space is formed by sampling at time T the common-offset(x0)traces which are taken from successive N CMP gathers.Each common-offset(x)trace gather brings a vector VX(N).The vectors obtained from different com-mon-offset trace gathers form a vector set in N-dimensional space,The principal component u1 of the vector set can be obtained by making eigenvalue decomposition.Then,projecting each vector VX(N) on the principal component u1 results in good noise suppression.