The Way of Structural Interpretation of Potential Fields Under Condition of a Priori Geological Information Minimum

Igor B. Movchan and Alexandra A. Yakovleva

National Mineral Resource University (University of Mines) Russia, 199106, St.-Petersburg, Vasil’evsky island, 21st line, 2, Russia

DOI : http://dx.doi.org/10.13005/bbra/1455

ABSTRACT: The aim of paper is in development of interpretation of potential and quasipotential fields which in geophysics traditionally includes the qualitative and quantitative approaches. To the first interpretation they relate the transformations of structure of measured signal: filtration and zoning. At the stage of qualitative interpretation the processed field is considered in the area of absence of sources of its anomalies and these fields keep the analyticity. The quantitative interpretation is in various recalculations of field in the depth, i.e. in the area of existence of anomalous geological sources in the small vicinity of which the gravitational, magnetic and electric potentials approach infinity. Under such transformations the geometrical and physical parameters of heterogeneities of geological half-space are reconstructed by the methods of solution of ill-posed problems. The last ones has some peculiarities: on one hand, it takes time with regard to the qualitative interpretation and, on the other hand, it rouses censure within geologists because of the necessity of simplification of reconstructed heterogeneities in geological media. The solution of ill-posed problem always has multivalued character: one anomaly corresponds to a wide class of models of geological heterogeneities with significant difference in geometry, elements of bedding, average physical properties. This difficulty is overcame by the set of independent methods of analytical continuation, one of which gives the structural image of geological cross section which is comparable to the seismic cross section.

KEYWORDS: Inverse problem; models; interactive fit; structural image; potential signal

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