Abstract: Analytic signal is a common tool for magnetic data processing and interpretation. Based on the relationship of different order analytic signals and their vertical derivative, this paper introduced a magnetic source variable depth imaging function with a depth scaled factor. The new method can be used for determining the position of filed source by using the maximum value of depth imaging, and estimating structural index on basis of the inverted depth and imaging maximum value. In addition, we can use the imaging results with different depth scaled factors and different orders to improve the reliability and usability of the new method. Model tests and applications indicate that the new method can    abtain  stronger computational  stability, higher spatial imaging resolution and more accurate field source parameter inversion results using lower-order derivatives, compared with the DEXP (depth from extreme points) methods of analytic signal ratio and local wavenumber.

Key words: magnetic source, analytic signal, depth imaging, structural index