Complex trace analysis effects a natural separation of amplitude from angle and allows definition of instantaneous attributes. The instantaneous amplitude defines single lobes for individual wavelets and, along with the instantaneous phase and frequency, has more power to resolve reflectors than trace amplitudes. In the case of strongly overlapping wavelets, the instantaneous amplitude and frequency have characteristics that help identify and distinguish wavelet interference. The instantaneous frequency, a measure of most energy-loaded or center frequency, traces frequency change with time. In time-lapse seismic surveys, the power of resolution and wavelet interference differentiation improves event picks and calculation of time shift and amplitude variation, and the representation of frequency facilitates the study of attenuation.