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# compute horizontal strain from a dislocation model (tong, sandwell, smith-konter) 

# it includes a viscoelastic model (PL6019) and elastic dislocation from fault creep and interpolation from GPS residuals 

# Steps:
1. run project.com (project the cartesian model into geographic)
2. run grid_surface.com (use greenspline (-C) instead of surface to avoid singularities)
3. run compute_strain.com (take gradient of horizontal velocity to get strain exx, eyy, exy)
4. run image_strain.com (computer second invariant)

# prepGPS/ is the folder contains the GPS data 

9/29/2015