The problem is that we start to get into the sticky question of what wavelets 'see' and what's a wavelet anyway, and hang on a minute why does seismic reflection even work? Personally, I'm skeptical, especially as we get more used to, and better at, looking at spectral decompositions of stacked and pre-stack data. I don't know why both are fairly easy to model, on the face of it. this patented technique I was introduced to at ConocoPhillips) have been the subject of quite a bit of discussion, in my experience. Anything of which people say, "This should be fine!" but offer no evidence.īack to my fourth point there. spectral shaping and wavelet stretch correction (e.g.At the very least, get volumes without them, and convince yourself they did no harm.
Things like wavelet stretch correction and spectral shaping are good for structural interpreters, but not for seismic analysts. Anything that is a sort of last resort, post hoc attempt to improve the data - what we might call 'cosmetic' treatments.(The thumbnail image for this post is from Duncan Emsley's essay in 52 Things.) Anything that puts the flattening of gathers before the accuracy of the data ( trim statics).In this way, relative effects should be preserved. If you must use windows, make them larger or longer than your areas and zones of interest. Anything with a window - spatial or temporal.Surface consistent: a shot-related affects all traces within a shot gather in the same way, independent of their receiver positions, and, a receiver-related affects all traces within a receiver gather in the same way, independent of their shot positions. What does that mean? According to Oliver Kuhn (now at Quantec in Toronto): Anything that is not surface consistent.I can't compile a list of exactly which processes will harm your AVO analysis (can anyone? Has anyone?), but I think I can start a list of things that you need to approach with caution and skepticism: For comparison, calculate the gas sand's response with the same parameters.Calculate the brine sand's response at the interface, given the rock properties and the angle range.Define a range of angles to calculate the response at.Define a gas-saturated sand for comparison with the wet sand.