f Resolution in Seismic Inversion- Spectral Gap or Spectral Overlap, Which is Harder to Handle?

Early methods that combined kinematic inversion with amplitude inversion have a gap in the resolved wavenumbers between those resolved by the amplitudes of the scattered field and those resolved by the kinematics. This gap required us to add extra constraints to the problem to recover a model that spans the full wavenumber spectrum. Three advances have brought us to a situation where that gap is often closed. 1) Modern seismic acquisition techniques with lower frequency sources and wider offsets have broadened the spectrum of wavenumbers resolved by single scattering inversions. 2) Full wave inversion using the two way wave equation data provides an accurate treatment of multiply scattered data and can accurately treat the low frequency part of the spectrum. 3) Improved tomography techniques now provide kinematic inversions that resolve more detail of the smooth background. This closing of the gap provides us with a new challenge. We have multiple measurements contributing to resolution of the same parts of the model. We must be careful to combine them in a way that honours the accuracy of each of the measurements.