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The eikonal equation in two dimensions is as follows (Aki and
Richards, 1980, ch.4):
| |
(1) |

where *s*(*x*,*z*) is the 2-dimensional slowness model and is
the traveltime field. Subscripts *x* and *z* denote partial derivatives
with respect to *x* and *z*, respectively.

Stanford Exploration Project

1/13/1998