Coordinates are specified in latitude, longitude, and burrial beneath the
local subsurface.
Moment tensors and vector sources are specified in spherical r, theta, and
phi coordinates. This corresponds to radial, colatitudinal, and
longitudinal directions. This is also know has the Harvard convention for
moment tensors.
For 2D the latitude will ignored and only the longitude will be assumed. This
is the default polar coordinate system with: