Are there rules of thumb for defining the size of a mesh in magnetic or gravity inversions?

Discretization
1

Hi All,

I guess each problem is unique when it comes to discretizing the subsurface, nevertheless, I was wondering if there is any key literature on that, or, if some of you have a rule of thumb to explore simple models before moving to higher orders of detail as you incorporate information into a reference model.

Best regards

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Taking a simple example here: For gravity or magnetic (this is different for DC, EM etc.) if you have data every 25 m, then horizontally you want your mesh cells to be ~25 m as well. The reasoning is that you want to be able to reproduce the wavelengths of the signals in your data. If horizontally you take bigger cells, then you will not be able to reproduce the higher frequency signals (this is related to the sampling theory concept of Nyquist frequency). But take too small cells, and you will lose your model continuity and create “islands of anomalies” around your data points.

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