  Imaging the anelastic deformation within the crust and lithosphere using
surface geophysical data remains a significant challenge in part due to the
wide range of physical processes operating at different depths and to various
levels of localization that they embody. Models of Earth's elastic properties
from seismological imaging combined with geodetic modeling may form the basis
of comprehensive rheological models of Earth's interior. However, representing
the structural complexity of faults and shear zones in numerical models of
deformation still constitutes a major difficulty. Here, we present numerical
techniques for high-precision models of deformation and stress around both
curvilinear faults and volumes undergoing anelastic (irreversible) strain in a
heterogenous elastic half-space. To that end, we enhance the software Gamra to
model triangular and rectangular fault patches and tetrahedral and cuboidal
strain volumes. This affords a means of rapid and accurate calculations of
elasto-static Green's functions for localized (e.g., faulting) and distributed
(e.g., viscoelastic) deformation in Earth's crust and lithosphere. We
demonstrate the correctness of the method with analytic tests, and we
illustrate its practical performance by solving for coseismic and postseismic
deformation following the 2015 Mw 7.8 Gorkha, Nepal earthquake to extremely
high precision.
