We developed an open source software for crustal strain analysis using the least-squares collocation method based on the spherical model of the earth. The software is able to simultaneously determine the signal and noise of the velocities at the observation points with the best possible removal of the observational errors, or at any other position with no velocity observation. Furthermore, the software can calculate strain and rotation rate tensors at any points of interest, including observation points, grid points or points along a fault line. The advantage of the software is that the sphericity of the earth is considered in all the calculations. Moreover, it can optionally consider the effect of the vertical velocities on the strain rates that is principally important for regions where vertical deformation is the major geophysical signal compared to the horizontal deformation.
Goudarzi, M. A., Cocard, M., & Santerre, R. (2015). GeoStrain: An open source software for calculating crustal strain rates. Computers and Geosciences, 82, 1–12. https://doi.org/10.1016/j.cageo.2015.05.007