RT Journal Article T1 A 3-D gravity inversion tool based on exploration of model possibilities A1 Camacho, Antonio A1 Montesinos, F. G. A1 Vieira, Ricardo AB A computational tool for the development and implementation of a recently published method of 3-D (three dimensional) inversion for gravity data is presented. This method seeks to determine the geometry of an indefinite number of anomalous bodies with prescribed (fixed or variable) density contrasts. Positive and negative values being indiscriminately accepted in the model. The approach is based on a prismatic partition of the subsurface and attempts to determine the anomalous bodies by means of a "growth" sequence, analysing (systematically or randomly) the several model possibilities and from that choosing the best for the growth progress. Moreover, a regional trend for the gravity data can be simultaneously adjusted. The non-uniqueness of the gravity inversion is avoided by means of a mixed condition about the residuals and the whole body anomalous mass. This imersion method has been applied with good results to simulation tests and to several real examples. Here, we present a main program that realises, the inversion according to several possibilities for general application (scale of the survey, fixed or variable density contrasts, optional smoothing, optional trend adjustment, systematic or random exploration, optional a priori information, weighting, etc.). This program is presented along with a previous program for selection of unknowns and parameters and another program for visual presentation of the results. All three programs are written in Fortran 77 and completes the Inversion tool. (C) 2002 Elsevier Science Ltd. All rights reserved. PB Pergamon-Elsevier SN 0098-3004 YR 2002 FD 2002 LK https://hdl.handle.net/20.500.14352/57449 UL https://hdl.handle.net/20.500.14352/57449 LA eng NO Araña, V., Camacho, A.G., Garcia, A., Montesinos, F.G.,Blanco, I., Vieira, R., Felpeto, A., 2000. The internal structure of Tenerife (Canary Islands) based on gravity, aeromagnetic and volcanological data. Journal of Volcanology and Geothermal Research 103, 43–64.Beltrao, J.F., Silva, J.B.C., Costa, J.C., 1991. Robust polynomial fitting method for regional gravity estimation. Geophysics 56, 80–89.Camacho, A.G., Montesinos, F.G., Vieira, R., 1997. A threedimensional gravity inversion applied to Sao Miguel Island (Azores). Journalof Geophysical Research 102, 7705–7715.Camacho, A.G., Montesinos, F.G., Vieira, R., 2000. Gravity inversion by means of growing bodies. Geophysics 65, 95–101.Enmark, T., 1981. A versatile interactive computer program for computation and automatic optimization of gravity models.Geoexploration 19, 47–66.Farquharson, C.G., Oldenburg, D.W., 1998. Non-linear inversion using general measures of data misfit and model structure. Geophysical Journal Internation al 134, 213–227.Montesinos, 1999. Inversi!on gravim!etrica 3D por t!ecnicas de evoluci!on. Aplicaci!on a la isla de Fuerteventura. Ph.D.Dissertation. University Complutense of Madrid. 212p.Pick, M., Picha, J., Vysk#ocil, V., 1973, Theory of the Earth’s Gravity Field. Elsevier, Amsterdam, 538 pp.Ren!e, R.M., 1986. Gravity inversion using open, reject, and ‘‘shape-of-anomaly’’ fill criteria. Geophysics 51 (4), 988–994.Tarantola, A., 1987. The Inverse Problem Theory: Methods for Data Fitting and ModelParamete r Estimation. Elsevier, Amsterdam, 613pp. DS Docta Complutense RD 6 may 2024