MAGNUM
MAGNUM is a collection of three programs (FOGO, VIDI and DYNO) for Multi-modal Applied Geophysical Numerical modelling on Unstructured Meshes. Despite the name, rectilinear meshes are also supported by this package. MAGNUM includes geophysical forward modelling and inversion programs.
FOGO
A program for forward modelling of geopysical data. It provides support for the following data types: scalar gravity data (vertical component other single Cartesian component), gradiometry (tensor) gravity data, first-arrival seismic traveltimes, magnetic data (TMI, xyz components, amplitude), muography, and IP/DC resistivity. EM methods will be added to the software soon.
VIDI
A program for mesh-based inversion that determines the physical property values or lithologies inside the mesh cells. This is a flexible, modular and highly functional program:
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The discretization is voxellized (many space-filling cells) on a 2D or 3D rectilinear or unstructured (triangular or tetrahedral) mesh.
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Two different inversion approaches: 1- the inversion can treat the model values as physical properties on continuous, but possibly bounded, ranges. 2- a lithological inversion can be designed such that only specific physical property values are allowed for each of the known or assumed rock types.
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The supported geophysical data types are: vertical component (scalar) gravity data, gradiometry (tensor) gravity data, magnetic data (TMI & xyz vector components, magnetic amplitude data, first-arrival seismic traveltimes, muography, and IP/DC resistivity. EM methods will be added to the software soon.
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Single or multiple data-types can be inverted (independent or joint inversion). There are various possible joint coupling strategies for any pair of physical property models: explicit linear relationship, implicit linear relationship, cross-gradient, clustering fuzzy c-means, and Gaussian.
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Magnetic vector inversion for remanent-affected magnetic data works with both Cartesian and spherical methods.
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For constrained inversions, bounds and reference models can be used.
DYNO
A surface geometry inversion program that determines the positions of surfaces in a geological model that represent the contacts between rock units. The discretization is a wireframe surface of tessellated triangles. Single or multiple data-types can be inverted. Gravity (vertical and gradiometry), magnetics and straight-ray seismic data are currently supported.