A mathematical method to determine seismic attributes, including reflection strength and instantaneous frequency, by using the Hilbert transform, a special form of the Fourier transform, and the quadrature trace, or the component of the signal that is 90 degrees out of phase.

The Fourier transform

a(t) = h(t) + jx(t),

where h(t) = seismic trace x(t) = quadrature trace

can be used to determine reflection strength by combining h and x: