GRAV MAG PRISM: A MATLAB/OCTAVE PROGRAM TO GENERATE GRAVITY AND MAGNETIC ANOMALIES DUE TO RECTANGULAR PRISMATIC BODIES

ABSTRACT . In this paper we present the GRAV MAG PRISM code to generate synthetic gravity and magnetic anomalies from rectangular prismatic bodies with arbitrary dimensions, densities and magnetizations. The code has been developed in a MATLAB/OCTAVE environment and provides a graphical and a numerical output, as well. The data are written in xyz (ASCII) format and can be contaminated with noise. We also summarize the theory and show some examples of the program’s applications. The code can be used for research and educational purposes and is freely-distributed by the authors on request. Keywords : gravity and magnetic anomalies, potential-field modeling, program. RESUMO . Neste trabalho e apresentado o programa GRAV MAG PRISM, o qual gera anomalias de gravidade e magneticas sinteticas a partir de corpos prismaticos retangulares com dimensoes, densidades e magnetizacoes arbitrarias. O codigo foi desenvolvido em ambiente MATLAB/OCTAVE, com saidas graficas e numericas. Os dados sao escritos no formato xyz (ASCII) e podem ser contaminados por ruidos. Neste trabalho tambem e apresentado um resumo da teoria e alguns exemplos de aplicacao do programa. O codigo acompanha um tutorial e pode ser utilizado para fins educacionais e de pesquisa, sendo de distribuicao gratuita atraves de solicitacao aos autores. Palavras-chave : anomalias gravimetricas e magneticas, modelagem de campos potenciais, programa.

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