Res2dinv

Supports on land, underwater and cross-borehole surveys
Supports the Wenner (alpha,beta,gamma), Wenner-Schlumberger, pole-pole, pole-dipole, inline dipole-dipole, equatorial dipole-dipole, gradient and non-conventional arrays.
Supports exact and approximate least-squares optimisation methods
Supports smooth and sharp constrasts inversions
Supports up to 16000 electrodes and 21000 data points on computers with 1GB RAM
Seamless inversion of very long survey lines using sparse inversion techniques