An important component in linking well information to seismic is the well to seismic tie. In RokDoc we have the Roy White wavelet extraction technique applied spatially to account for position issues, which we use to derive an optimum wavelet for synthetic seismic generation. A good tie gives us confidence that the seismic data is good quality especially if we have a consistent wavelet extracted from a number of wells. This wavelet is then taken into our inversion schemes to determine impedances or ultimately properties such as porosity or saturation.