Q tools: Summary of CREWES software for Q modelling and analysis

Gary F. Margrave

CREWES has a number of tools in our Matlab toolbox for modelling constant Q attenuation and analysis of the results. The analysis tools can also be applied to real data. This paper presents an overview of those tools and illustrates their use in a few simple cases. We have tools to generate the theoretical impulse response of 1D anelastic propagation, to build a Q matrix that applies first-order Q transmission effects to a stationary signal, to create an inverse Q matrix that removes Q effects, to calculate the drift time given a Q model, to drift correct a synthetic seismogram, to estimate Q from a seismogram, to build an empirical Q model from standard P-sonic and density logs, and to create a theoretical zero-offset VSP given models of Q, velocity, and density.