dMODELS, a MATLAB software package for modeling crustal deformation near volcanic centers and active faults using Global Navigation Satellite System data—User guide

dMODELS is a MATLAB software package that implements the most common analytical models used to interpret deformation measurements near faults and active volcanic centers. This manual focuses on inversion of deformation data from the Global Navigation Satellite System (GNSS). The included case studies emphasize the GNSS inversion component of the software. Source models include pressurized spherical, spheroidal, and horizontal sill (penny-crack) magma reservoirs in a homogeneous, elastic, isotropic, flat half-space. A topography correction is available for the spherical source. Dikes and faults are described following the mathematical notation for the rectangular dislocations in a homogeneous, elastic, flat half-space. Equations have been reviewed for typographical errors present in the original literature and verified against finite-element method numerical models. GNSS data from the 2006 eruption at Augustine Volcano, Alaska; the 1998–2000 unrest at Taal Volcano, Philippines; and the 2009 earthquake in L’Aquila, Italy, are used to demonstrate the application of the software package.