If we could arrive at such a state, the seismic waveforms would be able to tell us little else, and the model would combine aspects of both the velocity model and the reflectivity image. Generally speaking, the goal of seismic waveform inverse methods is to obtain and study the class of models that fully explain the data.
Instead, at any given point we only have the model, which we progressively try to improve until it finally it completely accounts for our seismic data in an ideal world we would be able to use the model to predict every minor wiggle on every trace from every shot gather in the survey. In order to answer the question posed in the title, it is helpful abandon the distinction between the model, and the image (perhaps, our naïve geophysicist will be happier too). However, for the naïve geophysicist learning about imaging for the first time, this separation seems strange –aren’t the velocity model and the reflectivity just two different ways of looking at the same earth? A whole industry has been constructed around this separation, and for good cause: the velocity model is a very smooth, low resolution representation required for successful imaging, while the final reflectivity image contains the detailed, structural images that interpreters need most. Traditional seismic imaging as widely practiced in the oil and gas industry, conceptually treats the seismic velocity model as if it were a separate entity from the seismic reflectivity image.
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