IGMAS+ is a software combining 3-D forward and inverse modeling, interactive visualization and interdisciplinary interpretation of potential fields and their applications under geophysical and geological data constrains.

The software has a long history starting 1988 and has seen continuous improvement since then with input by many contributors.
Since 2019, IGMAS+ is maintained and developed at The Helmholtz Centre Potsdam - GFZ German Research Centre for Geosciences by the staff of Section 4.5 – Basin Modelling and Section 5.2 – eScience Centre with strong ongoing support by H.-J. Götze and S. Schmidt from CAU Kiel.

The official webpage of IGMAS+ is available at https://www.gfz-potsdam.de/igmas.

Each major version of IGMAS+ is assigned with a DOI. Intermediate releases including changelog can be found at https://git.gfz-potsdam.de/igmas/igmas-releases/-/releases/.

In IGMAS+, the analytical solution of the volume integral for the gravity and magnetic effects of a homogeneous body relies on reducing the three-folded integral to an integral over the bounding polyhedrons (in IGMAS+, polyhedrons are constructed using triangles). The algorithm encompass all elements of the gravity and magnetic tensors. Optimized storage facilitates extremely fast inversion of material parameters and changes to the model geometry. This flexibility simplifies handling geometry changes, as the model geometry is promptly updated, and the field components are recalculated after each modification.

The additional ability to invert for the geometry of the individual body interface extends the inverse modelling capabilities. Thanks to its triangular model structure, IGMAS+ effectively manages complex structures, such as the overhangs of salt domes. The software accommodates remanent and induced magnetization of geological bodies and finds application in interpreting borehole gravity and magnetics.

The modeling process is guided by constrains from independent data sources, such as structural information, geological maps and seismic data, and is crucial for the genuine integration of 3D thermal modeling and/or full waveform inversion results. IGMAS+ is largely used in the creation of 3-D data-constrained subsurface structural density and susceptibility models at different spatial scales. Both large-scale models (thousands of square km) and regional (hundreds of square km), are important for understanding the drivers of geohazards. In this case IGMAS+ is versatile, capable of handling both flat (regional) and spherical models (global, when it is necessary to consider the curvature of the Earth) in 3D. Medium-scale models support studies on the usage of the subsurface as thermal, electrical or material storage in the context of energy transition. Small-scale (tens of square km) models are largely used in applied geophysics, typically in sub-salt and sub-basalt settings.

List of changes for Release 1.4.8840
Added
• Import of lines (#124, #188)
• Interface inversion functionality (#135)
• Bounding box for interface inversion (#142)
• Export of quality and standard deviation values per iteration after interface inversion (#146, #171)
• Nearest neighbour interpolation for empty voxels while importing voxel cubes (#158)
• Special panel for empty voxel cells after importing a voxel cube (#162)
Changed
• Colours and line styles for fields in the 2D view (#126)
• Triangulation check message corrected to Topology check (#156)
• Misleading wording in the voxelization panel: "cubes" changed to "cells" (#165)
• Redesign of the sectioning wizard (#44, #173, #217, #236, #242)
• Title of new model wizard (#174)
• Default header for imported CSV files (#219)
Fixed
• Incorrect 3D rendering of intersecting bitmaps with enabled transparency/alpha channel (#128, #192)
• Graphical issue after deletion of the stations (#136)
• Issues during interface inversion (#137, #143, #147, #151, #159, #170, #179)
• Problem with voxel import while using grouping option (#141)
• Exception in MarchingCubesPlugin (#144)
• Problem with density geoid inversion (#145)
• Problem with missing anomaly field after loading the project (#148)
• Visualization of crossing triangles in the 2D view (#149)
• Errors in voxelization resulting in voxels with zero density (#153)
• Problem with creating a project using horizon import (#154)
• Wrong effective density value in the information tab (#161, #246)
• Problem with SVG export from the Multiple Cutter View (#166)
• Coordinate issues while creating new project using import of horizons (#168, #169)
• Wrong voxel visualization in 2D View when using non•square voxel cells (#175)
• Bug with re-installation of older version on top of the newer (#176)
• Incorrect calculation of the border effect in case when the density of the model units is not given in t/m3 (#178)
• Wrong name for the standard deviation in linear parameter inversion, voxel effect (#189)
• Error in distance unit conversion while loading voxel cubes (#190)
• Incorrect vertical placement of loaded bitmaps in the Multiple Cutter View (#208)
• Not updating body volume values after automatic correction of polygon orientation (#216)
• Problem while loading horizons with identical points as CSV files (#218)
• Incorrect parsing of headers of certain TSURF GOCAD files (#220, #221)
• New body added to a model is not assigned the existing properties (#224)
• Installer is not creating shortcuts on Linux (#222)
• Wrong calculation of voxel effect when combined with triangulation (#227)
• Bug while rendering images in the WorldWind plugin (#230)
• Effective density in information tab is shown even outside of the voxel cube (#231)
• Wrong application of default voxel function to the bodies deactivated during the voxel import (#232)
• Voxel cube is not visible in the 2D View (#233)
• Wrong assignment of the voxel cells to bodies after geometry changes (#239)
• Image files with names containing space are not reloaded with project (#240)
• Problem with visualization and calculation after loading voxel cubes of susceptibility type (#243)
• Problem with loading projects created with earlier versions (#244)
• Wrong effective density in information tab while voxel factor is not equal to 1 (#246)

List of changes for Release 1.4.8707
Added
• An option to change the font size of the axes and colour bars in 2D Map View (#45)
• Reversed colour maps from the scientific colour map set (#45)
• An option to set up manually the limits and the step of isolines or contours (#45)
• An option to set up the colour bar position (#45)
• A possibility to load local KML/KMZ files in the WorldWind plugin (#123)
• An option in the object tree to show/hide fields in different views (#130)
• An option to remove the components and fields (#131)
• Added a WMS service (in the WorldWind plugin) by GFZ Potsdam based on maps.gfz-potsdam.de (#133)
Changed
• Flatlaf updated to 1.1.2
Fixed
• All visibility settings of calculated and measured fields are synchronised for comparability (#45)
• By default the colour bar for each field in 2D Maps View is placed horizontally below each panel (#45)
• Rounding of the contour (isoline) labels (#132)
• Adjustment of colour bar position in 2D Maps View (#125)
• Sorting and storing of the list of model parameters in body manager (#122)

List of changes for Release 1.4.8690
Added
• 58 new themes from JFormDesginer (#113)
• Possibility to select colormaps for fields and residuals from scientific colormap set (#45)
• Possibility to change contours for fields and residuals
Changed
• Old icon in wizards was replaced with new IGMAS icon (#108)
• Colormaps of the fields and residuals (#45)
• Mirrored residual colorbar limits to ensure white zero values (#45)
• Field rendering options are saved for each project (#45)
Fixed
• Wrong symbols in the license text due to encoding (#106)
• Problem with license wizard after installation (#112)
• Starting from icon in macOS (#107)
• Issue with mouse pointer (#118) related to working sections (#35)

List of changes for Release 1.4.8671
Added
• A possibility to choose units other than t/m3 during voxel import (#21)
• An option to perform update check (#96)
Changed
• GFZ logo in the starting view
• License attributes (#93, #98)
Fixed
• Bug with wrong calculation of anomaly if the voxel density unit is not t/m^3 (#74)
• Calculation of the body volumes (#32)
• Exception after closing a project (#95)
• Padding in the installer (#14)
• Update check wrongly notified that there is a newer version (#94)
• Installer link in popup update notification (#92)