Inversion of two-dimensional magnetic data using correlation factors between high-pass filtered anomalies

Abstract EN

The magnetic anomaly expression produced by most geologic structures can be represented by a continuous function in depth and index parameter (magnetic inclination) with an amplitude coefficient (magnetic moment).

Correlation factors between high-pass filtered anomalies of dif¬ferent or successive graticule spacings are used to determine the depth and the index parameter.

The computed depths are determined automatically from each correlation value for each index parameter value.

The computed depths are plotted against the index parameter representing a continuous correlation curve.

The solution for the depth and the index parameter of the buried structure is read at the common intersection of correlation curvcs.

The method can be applied not only to true residual anomalies of short pro¬file length but also to magnetic anomalies consisting of the combined effect of the residual component due to purely local structure and a regional com¬ponent represented by a linear trend.

Procedures are also formulated to es¬timate the amplitude coefficient.

The method is independent of the filtering process.

The method is illustrated by a theoretical example and tested on a field example from Arizona.