This is a list of free and open-source software for geological data handling and interpretation. The list is split into broad categories, depending on the intended use of the software and its scope of functionality.
Notice that 'free and open-source' requires that the source code is available and users are given a free software license. Simple being 'free of charge' is not sufficient—see gratis versus libre.
Microsoft Access is not necessary, the free runtime is sufficient. Simple graphical interface, Integrity reinforcement, Reporting tools, Satellite Database, Database Validation, Assays QA/QC management with graphics.
Open-source implicit geological modeling that allows for automation of model construction and is aimed to enable the implementation of probabilistic machine-learning methods, e.g. for uncertainty analysis.
Python library for the manipulation and storage of a wide range of geoscientific data (points, curve, surface, 2D and 3D grids) in geoh5 file format, natively supported by Geoscience ANALYST free 3D viewer
The following projects have unknown licensing, licenses or other conditions which place some restriction on use or redistribution, or which depend on non-open-source software like MATLAB or XVT (and therefore do not meet the Open Source Definition from the Open Source Initiative).
Free 3D visualization and communication software for integrated, multi-disciplinary geoscience and mining data and models, which also connects to Python through geoh5py, its open-source API
^Lurcock, P. C. and G. S. Wilson (2012), PuffinPlot: A versatile, user-friendly program for paleomagnetic analysis, Geochemistry, Geophysics, Geosystems, 13, Q06Z45, doi:10.1029/2012GC004098