Fractional-order Local Wavenumber - An Improved Source-parameter Estimator

We present an improved local wavenumber method, based on the fractional-order differentiation of potential fields. Such kind of differentiation allows a fractional-order local wavenumber to be defined, whose usefulness is two-fold: a) the positions of the peaks of the two different-order local wavenumber are essentially the same and also holds in their difference; b) the noise-enhancement may be kept to a minimum, if compared to standard local wavenumber, based on integer-order field differentiation.The fractional-order local wavenumber is applied to synthetic and real examples and it provided a good estimation of both depth to sources and structural index.