Figure 1. The concept of an energy packet (or wavelet packet) being used to define the time extents and polarities of reflection events. The wavelet that illuminates the geology is shown in the center. The resulting reflection trace is displayed on the left. The display on the right is a complex seismic trace consisting of a real part (which is the real trace on the left repeated as a solid-line wiggle) and an imaginary part (the Hilbert transform of the real trace shown by the dash-line wiggle). The amplitude envelope is the function that bounds this complex trace on the left and right so as to touch every positive and negative extremum of the real and imaginary parts of the complex trace.