Method of avoiding aliasing in slant stacking of seismic data

The method of transforming seismic data traces recorded in x-t space to .tau.-p space comprising the steps of:

• selecting an initial summing angle p;
• identifying frequency components of said input data liable to be aliased with respect to a given angle p, said frequency components of said data liable to be aliased are identified by the equation
• f=[2g.vertline.p-(x/tv.sup.2).vertline]sup.-1
• f is frequency component of the data liable to be aliased,
• p is the summing angle,
• g is the trace spacing,
• x is the source to receive distance at which the seismic data is taken,
• t is time measured from the input of seismic energy to the earth, and
• v is velocity of the seismic energy through the earth;
• filtering said frequency components liable to be aliased prior to summation to generate points for said p trace;
• summing individual elements of seismic traces in x-t space, said elements of said traces lying along a line making the angle p with respect to the horizontal to generate points on said p traces which together make up a .tau.-p transform;
• repeating said steps with respect to differing angles p;
• and
• plotting said p traces to generate a .tau.-p representation of said data.