# Assembly methods of solving inverse problems as an integral element of additive technologies for interpretations of gravity anomalies

## DOI:

https://doi.org/10.24028/gzh.0203-3100.v41i4.2019.177364## Keywords:

gravity survey, inverse problem, field source, effective density, assembly method, additive technologies## Abstract

In recent years, the theory of interpretation of gravitational anomalies has been replenished with fundamentally different from familiar, additive technologies for extracting information about the studied geo-density medium. The concept of «additivity» implies a summation in the results of the interpretation of information carried by each of the found admissible solutions to the inverse problem. At the same time, the results of the interpretation themselves are not expressed, as usual, in terms of one of these solutions. In the ore inverse problem of gravity exploration, an effective working tool for such technologies has become the assembly algorithms for constructing valid interpretation options. These algorithms have universal capabilities in the matter of accounting for a priori data and do not have high requirements for the formation of the initial approximation of the field source model, which is crucial from the point of view of their application in additive technologies. At the same time, all hitherto known modifications of the mounting method were designed for formulating inverse problems in which there are bodies with effective densities of the same sign. Due to the integration of the method with the procedure for separating gravitational fields, the problem of different sign densities was solved.

The separation of the observed field into two components, due to the influence of sources with positive and negative effective density, is carried out by the approximation method. To approximate the discrete values of gravity, the sets of elementary sources under each point of observation are used. The masses of sources are determined by solving a system of linear algebraic equations. The sources are successively immersed at different depths corresponding to different variants of the selection of the interpreted field components.

The article evaluates the current state and prospects for the further development of additive technologies for interpreting gravitational anomalies based on the methods that implement the concept of the mounting approach by V. N. Strakhov. Model of model examples are given illustrating the capabilities of the presented algorithms.

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*Geofizicheskiy Zhurnal*,

*41*(4), 40–59. https://doi.org/10.24028/gzh.0203-3100.v41i4.2019.177364

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